feat(processors): use pipelines across the codebase (#1452)

* Refactor observation preprocessing to use a modular pipeline system

- Introduced `RobotPipeline` and `ObservationProcessor` for handling observation transformations.
- Updated `preprocess_observation` to maintain backward compatibility while leveraging the new pipeline.
- Added tests for the new processing components and ensured they match the original functionality.
- Removed hardcoded logic in favor of a more flexible, composable architecture.

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* Refactor observation processing and improve modularity

- Updated `ObservationProcessor` to enhance the modular design for processing observations.
- Cleaned up imports and improved code readability by removing unnecessary lines and comments.
- Ensured backward compatibility while integrating new processing components.
- Added tests to validate the functionality of the updated processing architecture.

* Remove redundant tests for None observation and serialization methods in `test_observation_processor.py` to streamline the test suite and improve maintainability.

* Refactor processing architecture to use RobotProcessor

- Replaced instances of RobotPipeline with RobotProcessor across the codebase for improved modularity and clarity.
- Introduced ProcessorStepRegistry for better management of processing steps.
- Updated relevant documentation and tests to reflect the new processing structure.
- Enhanced the save/load functionality to support the new processor design.
- Added a model card template for RobotProcessor to facilitate sharing and documentation.

* Add RobotProcessor tutorial to documentation

- Introduced a new tutorial on using RobotProcessor for preprocessing robot data.
- Added a section in the table of contents for easy navigation to the new tutorial.
- The tutorial covers key concepts, real-world scenarios, and practical examples for effective use of the RobotProcessor pipeline.

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* Add normalization processor and related components

- Introduced `NormalizationProcessor` to handle both observation normalization and action unnormalization.
- Added `ObservationNormalizer` and `ActionUnnormalizer` classes for specific normalization tasks.
- Updated `__init__.py` to include the new `NormalizationProcessor` in the module exports.
- Enhanced `ObservationProcessor` with registration in the `ProcessorStepRegistry` for better modularity.
- Created `RenameProcessor` for renaming keys in observations, improving flexibility in data processing.

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* Enhance processing architecture with new components

- Added `RenameProcessor` to facilitate key renaming in observations, improving data handling flexibility.
- Updated `__init__.py` to include `RenameProcessor` in module exports.
- Refactored `NormalizationProcessor` and `ObservationNormalizer` to use `rsplit` for better key handling.
- Introduced comprehensive tests for `NormalizationProcessor` and `RenameProcessor` to ensure functionality and robustness.

* chore (docs): add docstring for processor

* fix (test): test factory

* fix(test): policies

* Update tests/processor/test_observation_processor.py

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Signed-off-by: Adil Zouitine <adilzouitinegm@gmail.com>

* chore(test): add suggestion made by copilot regarding numpy test

* fix(test): import issue

* Refactor normalization components and update tests

- Renamed `ObservationNormalizer` to `NormalizerProcessor` and `ActionUnnormalizer` to `UnnormalizerProcessor` for clarity.
- Consolidated normalization logic for both observations and actions into `NormalizerProcessor` and `UnnormalizerProcessor`.
- Updated tests to reflect the new class names and ensure proper functionality of normalization and unnormalization processes.
- Enhanced handling of missing statistics in normalization processes.

* chore (docstrin):Improve docstring for NormalizerProcessor

* feat (device processor): Implement device processor

* chore (batch handling): Enhance processing components with batch conversion utilities

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* fix(test): linting issue

* chore (output format): improves output format

* chore (type): add typing for multiprocess envs

* feat (overrides): Implement support for loading processors with parameter overrides

- Added the ability to provide non-serializable objects when loading processors from saved configurations using the `overrides` parameter.
- Enhanced error handling for invalid override keys and instantiation errors.
- Updated documentation and examples to illustrate the usage of overrides for both registered and unregistered steps.
- Added comprehensive tests to validate the new functionality and ensure backward compatibility.

* chore(normalization): addressing comments from copilot

* chore(learner): nit comment from copilot

* feat(pipeline): Enhance step_through method to support both tuple and dict inputs

* refactor(pipeline): Simplify observation and padding data handling in batch transitions

* Apply suggestions from code review

Co-authored-by: Simon Alibert <75076266+aliberts@users.noreply.github.com>
Signed-off-by: Adil Zouitine <adilzouitinegm@gmail.com>

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* refactor(pipeline): Introduce ComplementaryDataProcessor for handling complementary data in transitions

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* refactor(pipeline): Transition from tuple to dictionary format for EnvTransition

- Updated the EnvTransition structure to use a dictionary format instead of a tuple, enhancing readability and maintainability.
- Replaced instances of TransitionIndex with TransitionKey for accessing transition components.
- Adjusted related processing functions and tests to accommodate the new dictionary format, ensuring consistent handling of transitions across the codebase.

* refactor(observation_processor): Improve observation processing by using constants and simplifying pixel handling

- Introduced constants for observation keys to enhance readability.
- Streamlined the handling of the "pixels" key by copying observations first and processing images more clearly.
- Updated the environment state and agent position assignments to use the new constants, improving maintainability.

* feat(pipeline): Add hook unregistration functionality and enhance documentation

- Implemented methods to unregister before, after, and reset hooks in the RobotProcessor class, allowing for more flexible hook management.
- Enhanced documentation to clarify hook execution semantics and the implications of modifying transitions within hooks.
- Added comprehensive tests to verify the correct behavior of hook registration and unregistration, including error handling for non-existent hooks.

* refactor(pipeline): Clarify hook behavior and improve documentation

- Updated the RobotProcessor class to ensure hooks are strictly for observation and do not modify transitions, enhancing clarity and maintainability.
- Refactored hook registration methods to reflect the new behavior, ensuring they accept only functions that do not return modified transitions.
- Enhanced documentation to clearly outline the purpose of hooks and their execution semantics.
- Added tests to verify that hooks are not executed during the step_through method while ensuring they function correctly during the __call__ method.

* feat(pipeline): Add __repr__ method to RobotProcessor for improved readability

- Implemented a __repr__ method in the RobotProcessor class to provide a clear string representation of the processor, including step names and optional parameters like name and seed.
- Added comprehensive tests to validate the __repr__ output for various scenarios, including empty processors, single and multiple steps, custom names, and seed values.
- Ensured that the representation handles long lists of steps with truncation for better readability.

* chore(pipeline): Move _CFG_NAME along other class member

* refactor(pipeline): Utilize get_safe_torch_device for device assignment

- Replaced direct torch.device instantiation with get_safe_torch_device to ensure safe device handling.
- This change enhances code readability and maintains consistency in device management across the RobotProcessor class.

* refactor(pipeline): Enhance state filename generation and profiling method

- Updated state filename generation to use the registry name when available, improving clarity in saved files.
- Modified the profile_steps method to include a warmup_runs parameter, allowing for more controlled performance profiling.
- Ensured consistent conditions during profiling by deep copying transitions for each run, enhancing accuracy in timing results.

* chore(doc): address pip install commant lerobot that not exist yet

* feat(pipeline): Enhance configuration filename handling and state file naming

- Introduced support for custom configuration filenames in the `save_pretrained` method, allowing users to specify a filename instead of the default.
- Improved state file naming to include step indices, preventing conflicts when multiple processors of the same type are saved.
- Added automatic detection for configuration files when loading from a directory, with error handling for multiple files.
- Updated tests to validate new features, including custom filenames and automatic config detection.

* refactor(pipeline): Improve state file naming conventions for clarity and uniqueness

- Enhanced state file naming to include the processor's sanitized name, ensuring uniqueness when multiple processors are saved in the same directory.
- Updated tests to reflect changes in state file naming, verifying that filenames now include the processor name and step indices to prevent conflicts.
- Added a new test to validate state file naming when using multiple processors, ensuring distinct filenames for each processor's state files.

* docs(pipeline): Add clarification for repo name sanitization process

* Feat/pipeline add feature contract (#1637)

* Add feature contract to pipelinestep and pipeline

* Add tests

* Add processor tests

* PR feedback

* encorperate pr feedback

* type in doc

* oops

* docs(pipeline): Clarify transition handling and hook behavior

- Updated documentation to specify that hooks always receive transitions in EnvTransition format, ensuring consistent behavior across input formats.
- Refactored the step_through method to yield only EnvTransition objects, regardless of the input format, and updated related tests to reflect this change.
- Enhanced test assertions to verify the structure of results and the correctness of processing steps.

* refactor(pipeline): Remove to() method for device management

- Eliminated the to() method from RobotProcessor, which was responsible for moving tensor states to specified devices.
- Removed associated unit tests that validated the functionality of the to() method across various scenarios.
- Streamlined the pipeline code by focusing on other device management strategies.

* refactor(pipeline): Remove model card generation and streamline processor methods

- Eliminated the _generate_model_card method from RobotProcessor, which was responsible for generating README.md files from a template.
- Updated save_pretrained method to remove model card generation, focusing on serialization of processor definitions and parameters.
- Added default implementations for get_config, state_dict, load_state_dict, reset, and feature_contract methods in various processor classes to enhance consistency and usability.

* refactor(observation): Streamline observation preprocessing and remove unused processor methods

- Updated the `preprocess_observation` function to enhance image handling and ensure proper tensor formatting.
- Removed the `RobotProcessor` and associated transition handling from the `rollout` function, simplifying the observation processing flow.
- Integrated direct calls to `preprocess_observation` for improved clarity and efficiency in the evaluation script.

* refactor(pipeline): Rename parameters for clarity and enhance save/load functionality

- Updated parameter names in the save_pretrained and from_pretrained methods for improved readability, changing destination_path to save_directory and source to pretrained_model_name_or_path.
- Enhanced the save_pretrained method to ensure directory creation and file handling is consistent with the new parameter names.
- Streamlined the loading process in from_pretrained to utilize loaded_config for better clarity and maintainability.

* refactor(pipeline): minor improvements (#1684)

* chore(pipeline): remove unused features + device torch + envtransition keys

* refactor(pipeline): ImageProcessor & StateProcessor are both implemented directly in VanillaObservationPRocessor

* refactor(pipeline): RenameProcessor now inherits from ObservationProcessor + remove unused code

* test(pipeline): fix broken test after refactors

* docs(pipeline): update docstrings VanillaObservationProcessor

* chore(pipeline): move None check to base pipeline classes

* feat(processors): Introduce processors for various policy types

- Added `make_processor` function to create processor instances for different policy types, including `tdmpc`, `diffusion`, `act`, `vqbet`, `pi0`, `pi0fast`, `sac`, and `reward_classifier`.
- Implemented corresponding processor files for each policy type, encapsulating normalization and unnormalization steps.
- Updated existing policies to remove direct normalization dependencies, enhancing modularity and clarity.
- Enhanced test coverage to validate the integration of new processors with existing policy configurations.

* refactor(learner): Remove normalization from cached image features retrieval

- Simplified the retrieval of observation features by removing the normalization step from the `get_cached_image_features` method calls.
- This change enhances clarity and aligns with the recent updates to policy processors.

* refactor(policies): Remove unnormalization step from action predictions

- Eliminated the unnormalization of actions in both `TDMPCPolicy` and `VQBeTPolicy` classes to streamline action prediction.
- This change improves code clarity and aligns with recent updates to policy processors.

* feat(train): Integrate preprocessor into training pipeline

* refactor(train): Update preprocessor initialization to include dataset statistics

* refactor(policies): Enhance processor creation and add NaN detection hook

* feat(record): Integrate RobotProcessor into recording loop and update policy handling

- Added support for RobotProcessor in the record_loop function to enhance data processing capabilities.
- Updated the logic to reset both policy and processor when provided, ensuring proper state management.
- Modified action prediction to utilize the processor, improving the overall functionality of the recording process.
- Adjusted the save_checkpoint function to include preprocessor state saving, enhancing checkpointing capabilities.

* feat(migration): Add script for migrating policy models with normalization layers

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* feat(migrate): Enhance migration script to create preprocessor and postprocessor for policy models

- Updated the migration script to generate both a preprocessor and a postprocessor, improving the handling of normalization for training and inference.
- Added functionality to convert features to PolicyFeature objects, ensuring compatibility with the new processor architecture.
- Refined the extraction and removal of normalization statistics and layers, streamlining the migration process.
- Improved error handling for missing mandatory configuration fields during model instantiation.

* feat(migrate): Add model card generation and saving to migration script

- Implemented functionality to generate and save a model card for the migrated model, including metadata such as dataset repository ID, license, and tags.
- Enhanced the script to push the model card to the hub if requested, improving model documentation and accessibility.
- Refactored the saving process to ensure the model card is saved locally and uploaded correctly when pushing to the hub.

* feat(processor): Introduce ToBatchProcessor for handling observation batching

- Added ToBatchProcessor to ensure observations have proper batch dimensions for model processing.
- Implemented functionality to add batch dimensions to state and image observations as needed.
- Created comprehensive unit tests to validate the processor's behavior with various tensor dimensions and types.
- Ensured compatibility with existing transition keys and maintained the integrity of non-observation data.

* feat(processors): Add ToBatchProcessor to multiple policy processors

- Integrated ToBatchProcessor into various policy processors to handle observation batching.
- Updated make functions for act, diffusion, pi0, pi0fast, sac, smolvla, tdmpc, and vqbet processors to include the new batching functionality.
- Ensured consistency across all processor implementations for improved data handling.

* refactor(factory): Remove unused imports and NaN detection hook from processor creation

* feat(batch_processor): Enhance ToBatchProcessor to handle action batching

- Updated ToBatchProcessor to add batch dimensions to actions in addition to observations.
- Implemented separate methods for processing observations and actions, improving code readability.
- Added comprehensive unit tests to validate action batching functionality across various tensor dimensions and types.

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* feat(factory): Enhance make_processor to support preprocessor and postprocessor configuration

- Introduced ProcessorConfigKwargs TypedDict for better type safety in processor configuration.
- Updated make_processor to accept preprocessor and postprocessor configuration filenames, improving flexibility in processor instantiation.
- Refactored the loading of pretrained processors to utilize the new configuration options.

* refactor(factory): Clean up imports in factory.py

- Removed unused import of IdentityProcessor to streamline the code.

* feat(migrate): Extend load_model_from_hub to include train configuration

- Updated load_model_from_hub to return the train configuration alongside the model state_dict and config.
- Modified main function to handle the additional train configuration when loading models from both the hub and local paths.
- Adjusted dataset_repo_id extraction to utilize the train configuration for improved accuracy.

* refactor(record): Rename processor parameters and update processing logic

- Renamed `processor` to `preprocessor` and added `postprocessor` parameter for clarity.
- Updated the `record_loop` and `predict_action` functions to utilize the new preprocessor and postprocessor, enhancing the processing flow.
- Ensured compatibility with existing functionality while improving code readability.

* feat(batch_processor): Add task field processing to ToBatchProcessor

- Enhanced ToBatchProcessor to wrap string tasks in a list, adding batch dimensions for compatibility with model inference.
- Implemented a new method for processing complementary data, ensuring that task values are correctly handled as either strings or lists of strings.
- Added comprehensive unit tests to validate task processing, including edge cases and in-place mutation of complementary data.

* feat(normalization): Implement IDENTITY mode for normalization and unnormalization

- Enhanced NormalizerProcessor and UnnormalizerProcessor to support IDENTITY mode, allowing features to bypass normalization when specified.
- Updated processing logic to check normalization modes and handle missing statistics gracefully.
- Added comprehensive unit tests to validate IDENTITY mode functionality for both observations and actions, ensuring correct behavior across various scenarios.
- Improved error handling for unsupported normalization modes.

* fix(rebase): remove residual normalization layer:

* refactor(diffusion): remove normalization layer from input processing

* refactor(normalization): Remove unused state dict transformation methods and streamline imports

- Eliminated the _transform_state_dict_keys and _load_as_safetensor methods from PI0Policy, simplifying the model loading process.
- Cleaned up imports in modeling_pi0.py by removing log_model_loading_keys and init_logging.
- Updated TDMPCPolicy and VQBeTPolicy to handle action removal from batches during offline evaluation.
- Introduced hotswap_stats function in normalize_processor.py to update normalization statistics dynamically, with corresponding tests to ensure functionality.

* refactor(normalization): Clean up imports in normalize_processor.py

* feat(batch_processor): Add feature_contract method to ToBatchProcessor

- Introduced feature_contract method that returns features without modification, maintaining the no-op behavior of the processor.
- This addition enhances the flexibility of the ToBatchProcessor for future feature processing needs.

* fix(dependencies): Update transformers dependency constraint to allow only versions up to 4.52.0

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* feature(pipeline): port tokenizer pipeline for VLA (#1645)

* feat(tokenizer): Introduce TokenizerProcessor for text tokenization

- Added TokenizerProcessor class to handle tokenization of task strings using Hugging Face's AutoTokenizer.
- Supports both string and list inputs, with customizable parameters for task key, output key, and tokenization settings.
- Implemented comprehensive unit tests to validate functionality, including handling of various input scenarios and integration with RobotProcessor.
- Updated types.py to include LANGUAGE feature type and modified __init__.py to register the new processor.

* feat(language): Enhance language processing in TokenizerProcessor

- Added OBS_LANGUAGE constant to define the observation language key.
- Updated TokenizerProcessor to store tokenized task data in the observation dictionary, ensuring compatibility with the new language feature.
- Introduced Pi0NewLineProcessor to append newlines to tasks for proper tokenization.
- Modified tests to validate the integration of language tokens and attention masks in the observation structure.

* feat(tokenizer): Add padding configuration to TokenizerProcessor

- Introduced `padding_side` parameter to the TokenizerProcessor for customizable padding direction.
- Updated the `make_pi0_processor` function to include the new padding configuration.
- Enhanced unit tests to validate the functionality of the `padding_side` parameter in various scenarios.

* feat(processor): Add state management methods to Pi0NewLineProcessor

* feat(normalization): Track normalization and unnormalization info in complementary data

- Updated NormalizerProcessor and UnnormalizerProcessor to accept additional parameters for tracking normalization modes.
- Enhanced the __call__ methods to store normalization and unnormalization information in the complementary data of transitions.
- Added unit tests to verify the correct tracking of normalization info, including scenarios with missing stats and selective normalization keys.

* feat(factory): Add preprocessor and postprocessor overrides to ProcessorConfigKwargs

- Updated ProcessorConfigKwargs to include optional overrides for preprocessor and postprocessor configurations.
- Enhanced the make_processor function to utilize the new overrides, allowing for more flexible processor initialization.

* feat(processors): Integrate RenameProcessor into various processor configurations

- Added RenameProcessor to the input steps of multiple processor functions, including make_act_processor, make_diffusion_processor, make_pi0_processor, make_sac_processor, make_tdmpc_processor, make_vqbet_processor, and make_smolvla_processor.
- Consolidated normalization features from input and output into a single NormalizerProcessor for improved efficiency.
- Updated the input steps to ensure compatibility with the new RenameProcessor integration.

* feat(smolvla): Refactor language processing and introduce new line processor (#1658)

- Removed the prepare_language method and directly accessed language tokens and masks from the batch using the OBS_LANGUAGE constant.
- Added SmolVLANewLineProcessor to ensure tasks end with a newline, enhancing tokenization compatibility.
- Updated the make_smolvla_processor function to include the new line processor and tokenizer processor for improved input handling.

* feture(policies): add device processor (#1659)

* feat(processors): Integrate DeviceProcessor into multiple processor configurations

- Added DeviceProcessor to the input and output steps of various processor functions, including make_act_processor, make_diffusion_processor, make_pi0_processor, make_pi0fast_processor, make_sac_processor, make_tdmpc_processor, make_vqbet_processor, and make_smolvla_processor.
- Enhanced the DeviceProcessor class with state management methods and ensured compatibility with existing processor pipelines.
- Introduced unit tests for DeviceProcessor to validate functionality across different scenarios, including CPU and CUDA operations.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* refactor(pipeline): Remove to() method for device management

- Eliminated the to() method from RobotProcessor, which was responsible for moving tensor states to specified devices.
- Removed associated unit tests that validated the functionality of the to() method across various scenarios.
- Streamlined the pipeline code by focusing on other device management strategies.

* feat(processor): Enhance DeviceProcessor with float dtype conversion

- Added support for optional float dtype conversion in DeviceProcessor, allowing tensors to be converted to specified floating-point types while preserving non-float types.
- Implemented validation for float dtype input and updated the processor's configuration methods to include float dtype.
- Refactored tensor processing logic to streamline device movement and dtype conversion.
- Introduced comprehensive unit tests to validate the new float dtype functionality across various scenarios.

* feat(policies): Add new line processors and update module exports

* feat(processor): Enhance batch and device processors to handle index and task_index fields

- Added logic to ToBatchProcessor for unsqueezing 0D tensors for index and task_index fields, ensuring they are processed as 1D tensors.
- Updated DeviceProcessor to process index and task_index fields in complementary data, preserving their tensor types and ensuring non-tensor fields remain unchanged.
- Enhanced unit tests to validate the correct handling of index and task_index fields across various scenarios, including device compatibility and dtype preservation.

* refactor(processors): Standardize processor naming conventions

- Updated processor names across various files to use a consistent "robot_preprocessor" and "robot_postprocessor" format.
- Modified the make_processor functions in factory, act, diffusion, pi0, pi0fast, sac, smolvla, tdmpc, and vqbet to reflect the new naming scheme.
- Enhanced the pipeline configuration to align with the updated processor names, improving clarity and maintainability.

* refactor(factory): Update processor configuration and type hints

- Changed return type of get_policy_class to type[PreTrainedPolicy] for improved type safety.
- Enhanced make_processor function to utilize dataset_stats in processor creation for better flexibility.
- Updated ProcessorConfigKwargs to include dataset_stats, allowing for more comprehensive processor configurations.
- Streamlined processor initialization by removing unnecessary kwargs and ensuring clarity in processor type handling.

* refactor(factory, pi0fast): Update processor function names and parameters

- Renamed make_pi0_processor to make_pi0fast_processor for clarity and consistency.
- Updated parameter names in the factory's make_processor function to use pretrained_model_name_or_path instead of source, enhancing readability and alignment with naming conventions.

* fix(train.py) push postprocessor with preprocessor
- Add preprocesser policy overrides for device and rename_map
- Add rename_map to DatasetRecordConfig (record.py)

* refactor(device_processor): Update device handling and improve type hints

- Changed device attribute type from torch.device to str for better clarity.
- Introduced a private _device attribute to store the actual torch.device instance.
- Updated tests to conditionally check for CUDA availability, ensuring compatibility across different environments.
- Refactored device-related assertions in tests to use a consistent approach for device type verification.

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* test(tokenizer_processor): Add require_package decorator for transformers

- Introduced @require_package("transformers") decorator in multiple test functions to ensure the transformers package is available before running tests.
- This change enhances test reliability by preventing failures due to missing dependencies.

* refactor(migrate_policy_normalization): Enhance preprocessor and postprocessor structure

- Introduced RenameProcessor in the preprocessor to handle renaming features.
- Combined input and output features in a single NormalizerProcessor for improved efficiency.
- Updated RobotProcessor initialization to clarify step naming for preprocessor and postprocessor.
- Added DeviceProcessor to both preprocessor and postprocessor for better device management.

* Integrate pipeline and add phone teleop (#1681)

* Add normalization processor and related components

- Introduced `NormalizationProcessor` to handle both observation normalization and action unnormalization.
- Added `ObservationNormalizer` and `ActionUnnormalizer` classes for specific normalization tasks.
- Updated `__init__.py` to include the new `NormalizationProcessor` in the module exports.
- Enhanced `ObservationProcessor` with registration in the `ProcessorStepRegistry` for better modularity.
- Created `RenameProcessor` for renaming keys in observations, improving flexibility in data processing.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Enhance processing architecture with new components

- Added `RenameProcessor` to facilitate key renaming in observations, improving data handling flexibility.
- Updated `__init__.py` to include `RenameProcessor` in module exports.
- Refactored `NormalizationProcessor` and `ObservationNormalizer` to use `rsplit` for better key handling.
- Introduced comprehensive tests for `NormalizationProcessor` and `RenameProcessor` to ensure functionality and robustness.

* chore (docs): add docstring for processor

* fix (test): test factory

* fix(test): policies

* Update tests/processor/test_observation_processor.py

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Signed-off-by: Adil Zouitine <adilzouitinegm@gmail.com>

* chore(test): add suggestion made by copilot regarding numpy test

* fix(test): import issue

* Refactor normalization components and update tests

- Renamed `ObservationNormalizer` to `NormalizerProcessor` and `ActionUnnormalizer` to `UnnormalizerProcessor` for clarity.
- Consolidated normalization logic for both observations and actions into `NormalizerProcessor` and `UnnormalizerProcessor`.
- Updated tests to reflect the new class names and ensure proper functionality of normalization and unnormalization processes.
- Enhanced handling of missing statistics in normalization processes.

* chore (docstrin):Improve docstring for NormalizerProcessor

* feat (device processor): Implement device processor

* chore (batch handling): Enhance processing components with batch conversion utilities

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* fix(test): linting issue

* chore (output format): improves output format

* chore (type): add typing for multiprocess envs

* feat (overrides): Implement support for loading processors with parameter overrides

- Added the ability to provide non-serializable objects when loading processors from saved configurations using the `overrides` parameter.
- Enhanced error handling for invalid override keys and instantiation errors.
- Updated documentation and examples to illustrate the usage of overrides for both registered and unregistered steps.
- Added comprehensive tests to validate the new functionality and ensure backward compatibility.

* chore(normalization): addressing comments from copilot

* chore(learner): nit comment from copilot

* feat(pipeline): Enhance step_through method to support both tuple and dict inputs

* refactor(pipeline): Simplify observation and padding data handling in batch transitions

* Apply suggestions from code review

Co-authored-by: Simon Alibert <75076266+aliberts@users.noreply.github.com>
Signed-off-by: Adil Zouitine <adilzouitinegm@gmail.com>

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* refactor(pipeline): Introduce ComplementaryDataProcessor for handling complementary data in transitions

* fix(ci): temporary fix on dataset deps version

* feat(processors): Introduce processors for various policy types

- Added `make_processor` function to create processor instances for different policy types, including `tdmpc`, `diffusion`, `act`, `vqbet`, `pi0`, `pi0fast`, `sac`, and `reward_classifier`.
- Implemented corresponding processor files for each policy type, encapsulating normalization and unnormalization steps.
- Updated existing policies to remove direct normalization dependencies, enhancing modularity and clarity.
- Enhanced test coverage to validate the integration of new processors with existing policy configurations.

* refactor(learner): Remove normalization from cached image features retrieval

- Simplified the retrieval of observation features by removing the normalization step from the `get_cached_image_features` method calls.
- This change enhances clarity and aligns with the recent updates to policy processors.

* refactor(policies): Remove unnormalization step from action predictions

- Eliminated the unnormalization of actions in both `TDMPCPolicy` and `VQBeTPolicy` classes to streamline action prediction.
- This change improves code clarity and aligns with recent updates to policy processors.

* feat(train): Integrate preprocessor into training pipeline

* refactor(train): Update preprocessor initialization to include dataset statistics

* refactor(policies): Enhance processor creation and add NaN detection hook

* refactor(train): Update memory pinning logic for mps compatibility

* feat: initial commit phone teleop

* ugly delta control

* use quaternion

* Refactor observation preprocessing to use a modular pipeline system

- Introduced `RobotPipeline` and `ObservationProcessor` for handling observation transformations.
- Updated `preprocess_observation` to maintain backward compatibility while leveraging the new pipeline.
- Added tests for the new processing components and ensured they match the original functionality.
- Removed hardcoded logic in favor of a more flexible, composable architecture.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Refactor observation processing and improve modularity

- Updated `ObservationProcessor` to enhance the modular design for processing observations.
- Cleaned up imports and improved code readability by removing unnecessary lines and comments.
- Ensured backward compatibility while integrating new processing components.
- Added tests to validate the functionality of the updated processing architecture.

* Remove redundant tests for None observation and serialization methods in `test_observation_processor.py` to streamline the test suite and improve maintainability.

* Refactor processing architecture to use RobotProcessor

- Replaced instances of RobotPipeline with RobotProcessor across the codebase for improved modularity and clarity.
- Introduced ProcessorStepRegistry for better management of processing steps.
- Updated relevant documentation and tests to reflect the new processing structure.
- Enhanced the save/load functionality to support the new processor design.
- Added a model card template for RobotProcessor to facilitate sharing and documentation.

* Add RobotProcessor tutorial to documentation

- Introduced a new tutorial on using RobotProcessor for preprocessing robot data.
- Added a section in the table of contents for easy navigation to the new tutorial.
- The tutorial covers key concepts, real-world scenarios, and practical examples for effective use of the RobotProcessor pipeline.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Add normalization processor and related components

- Introduced `NormalizationProcessor` to handle both observation normalization and action unnormalization.
- Added `ObservationNormalizer` and `ActionUnnormalizer` classes for specific normalization tasks.
- Updated `__init__.py` to include the new `NormalizationProcessor` in the module exports.
- Enhanced `ObservationProcessor` with registration in the `ProcessorStepRegistry` for better modularity.
- Created `RenameProcessor` for renaming keys in observations, improving flexibility in data processing.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Enhance processing architecture with new components

- Added `RenameProcessor` to facilitate key renaming in observations, improving data handling flexibility.
- Updated `__init__.py` to include `RenameProcessor` in module exports.
- Refactored `NormalizationProcessor` and `ObservationNormalizer` to use `rsplit` for better key handling.
- Introduced comprehensive tests for `NormalizationProcessor` and `RenameProcessor` to ensure functionality and robustness.

* chore (docs): add docstring for processor

* fix (test): test factory

* fix(test): policies

* Update tests/processor/test_observation_processor.py

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Signed-off-by: Adil Zouitine <adilzouitinegm@gmail.com>

* chore(test): add suggestion made by copilot regarding numpy test

* fix(test): import issue

* Refactor normalization components and update tests

- Renamed `ObservationNormalizer` to `NormalizerProcessor` and `ActionUnnormalizer` to `UnnormalizerProcessor` for clarity.
- Consolidated normalization logic for both observations and actions into `NormalizerProcessor` and `UnnormalizerProcessor`.
- Updated tests to reflect the new class names and ensure proper functionality of normalization and unnormalization processes.
- Enhanced handling of missing statistics in normalization processes.

* chore (docstrin):Improve docstring for NormalizerProcessor

* feat (device processor): Implement device processor

* chore (batch handling): Enhance processing components with batch conversion utilities

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* fix(test): linting issue

* chore (output format): improves output format

* chore (type): add typing for multiprocess envs

* feat (overrides): Implement support for loading processors with parameter overrides

- Added the ability to provide non-serializable objects when loading processors from saved configurations using the `overrides` parameter.
- Enhanced error handling for invalid override keys and instantiation errors.
- Updated documentation and examples to illustrate the usage of overrides for both registered and unregistered steps.
- Added comprehensive tests to validate the new functionality and ensure backward compatibility.

* chore(normalization): addressing comments from copilot

* chore(learner): nit comment from copilot

* feat(pipeline): Enhance step_through method to support both tuple and dict inputs

* refactor(pipeline): Simplify observation and padding data handling in batch transitions

* Apply suggestions from code review

Co-authored-by: Simon Alibert <75076266+aliberts@users.noreply.github.com>
Signed-off-by: Adil Zouitine <adilzouitinegm@gmail.com>

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* refactor(pipeline): Introduce ComplementaryDataProcessor for handling complementary data in transitions

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* refactor(pipeline): Transition from tuple to dictionary format for EnvTransition

- Updated the EnvTransition structure to use a dictionary format instead of a tuple, enhancing readability and maintainability.
- Replaced instances of TransitionIndex with TransitionKey for accessing transition components.
- Adjusted related processing functions and tests to accommodate the new dictionary format, ensuring consistent handling of transitions across the codebase.

* refactor(observation_processor): Improve observation processing by using constants and simplifying pixel handling

- Introduced constants for observation keys to enhance readability.
- Streamlined the handling of the "pixels" key by copying observations first and processing images more clearly.
- Updated the environment state and agent position assignments to use the new constants, improving maintainability.

* feat(pipeline): Add hook unregistration functionality and enhance documentation

- Implemented methods to unregister before, after, and reset hooks in the RobotProcessor class, allowing for more flexible hook management.
- Enhanced documentation to clarify hook execution semantics and the implications of modifying transitions within hooks.
- Added comprehensive tests to verify the correct behavior of hook registration and unregistration, including error handling for non-existent hooks.

* refactor(pipeline): Clarify hook behavior and improve documentation

- Updated the RobotProcessor class to ensure hooks are strictly for observation and do not modify transitions, enhancing clarity and maintainability.
- Refactored hook registration methods to reflect the new behavior, ensuring they accept only functions that do not return modified transitions.
- Enhanced documentation to clearly outline the purpose of hooks and their execution semantics.
- Added tests to verify that hooks are not executed during the step_through method while ensuring they function correctly during the __call__ method.

* feat(pipeline): Add __repr__ method to RobotProcessor for improved readability

- Implemented a __repr__ method in the RobotProcessor class to provide a clear string representation of the processor, including step names and optional parameters like name and seed.
- Added comprehensive tests to validate the __repr__ output for various scenarios, including empty processors, single and multiple steps, custom names, and seed values.
- Ensured that the representation handles long lists of steps with truncation for better readability.

* chore(pipeline): Move _CFG_NAME along other class member

* refactor(pipeline): Utilize get_safe_torch_device for device assignment

- Replaced direct torch.device instantiation with get_safe_torch_device to ensure safe device handling.
- This change enhances code readability and maintains consistency in device management across the RobotProcessor class.

* refactor(pipeline): Enhance state filename generation and profiling method

- Updated state filename generation to use the registry name when available, improving clarity in saved files.
- Modified the profile_steps method to include a warmup_runs parameter, allowing for more controlled performance profiling.
- Ensured consistent conditions during profiling by deep copying transitions for each run, enhancing accuracy in timing results.

* chore(doc): address pip install commant lerobot that not exist yet

* feat(pipeline): Enhance configuration filename handling and state file naming

- Introduced support for custom configuration filenames in the `save_pretrained` method, allowing users to specify a filename instead of the default.
- Improved state file naming to include step indices, preventing conflicts when multiple processors of the same type are saved.
- Added automatic detection for configuration files when loading from a directory, with error handling for multiple files.
- Updated tests to validate new features, including custom filenames and automatic config detection.

* refactor(pipeline): Improve state file naming conventions for clarity and uniqueness

- Enhanced state file naming to include the processor's sanitized name, ensuring uniqueness when multiple processors are saved in the same directory.
- Updated tests to reflect changes in state file naming, verifying that filenames now include the processor name and step indices to prevent conflicts.
- Added a new test to validate state file naming when using multiple processors, ensuring distinct filenames for each processor's state files.

* docs(pipeline): Add clarification for repo name sanitization process

* feat(processors): Introduce processors for various policy types

- Added `make_processor` function to create processor instances for different policy types, including `tdmpc`, `diffusion`, `act`, `vqbet`, `pi0`, `pi0fast`, `sac`, and `reward_classifier`.
- Implemented corresponding processor files for each policy type, encapsulating normalization and unnormalization steps.
- Updated existing policies to remove direct normalization dependencies, enhancing modularity and clarity.
- Enhanced test coverage to validate the integration of new processors with existing policy configurations.

* refactor(learner): Remove normalization from cached image features retrieval

- Simplified the retrieval of observation features by removing the normalization step from the `get_cached_image_features` method calls.
- This change enhances clarity and aligns with the recent updates to policy processors.

* refactor(policies): Remove unnormalization step from action predictions

- Eliminated the unnormalization of actions in both `TDMPCPolicy` and `VQBeTPolicy` classes to streamline action prediction.
- This change improves code clarity and aligns with recent updates to policy processors.

* feat(train): Integrate preprocessor into training pipeline

* refactor(train): Update preprocessor initialization to include dataset statistics

* refactor(policies): Enhance processor creation and add NaN detection hook

* feat(record): Integrate RobotProcessor into recording loop and update policy handling

- Added support for RobotProcessor in the record_loop function to enhance data processing capabilities.
- Updated the logic to reset both policy and processor when provided, ensuring proper state management.
- Modified action prediction to utilize the processor, improving the overall functionality of the recording process.
- Adjusted the save_checkpoint function to include preprocessor state saving, enhancing checkpointing capabilities.

* feat(migration): Add script for migrating policy models with normalization layers

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* feat(migrate): Enhance migration script to create preprocessor and postprocessor for policy models

- Updated the migration script to generate both a preprocessor and a postprocessor, improving the handling of normalization for training and inference.
- Added functionality to convert features to PolicyFeature objects, ensuring compatibility with the new processor architecture.
- Refined the extraction and removal of normalization statistics and layers, streamlining the migration process.
- Improved error handling for missing mandatory configuration fields during model instantiation.

* feat(migrate): Add model card generation and saving to migration script

- Implemented functionality to generate and save a model card for the migrated model, including metadata such as dataset repository ID, license, and tags.
- Enhanced the script to push the model card to the hub if requested, improving model documentation and accessibility.
- Refactored the saving process to ensure the model card is saved locally and uploaded correctly when pushing to the hub.

* feat(processor): Introduce ToBatchProcessor for handling observation batching

- Added ToBatchProcessor to ensure observations have proper batch dimensions for model processing.
- Implemented functionality to add batch dimensions to state and image observations as needed.
- Created comprehensive unit tests to validate the processor's behavior with various tensor dimensions and types.
- Ensured compatibility with existing transition keys and maintained the integrity of non-observation data.

* feat(processors): Add ToBatchProcessor to multiple policy processors

- Integrated ToBatchProcessor into various policy processors to handle observation batching.
- Updated make functions for act, diffusion, pi0, pi0fast, sac, smolvla, tdmpc, and vqbet processors to include the new batching functionality.
- Ensured consistency across all processor implementations for improved data handling.

* refactor(factory): Remove unused imports and NaN detection hook from processor creation

* feat(batch_processor): Enhance ToBatchProcessor to handle action batching

- Updated ToBatchProcessor to add batch dimensions to actions in addition to observations.
- Implemented separate methods for processing observations and actions, improving code readability.
- Added comprehensive unit tests to validate action batching functionality across various tensor dimensions and types.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* feat(factory): Enhance make_processor to support preprocessor and postprocessor configuration

- Introduced ProcessorConfigKwargs TypedDict for better type safety in processor configuration.
- Updated make_processor to accept preprocessor and postprocessor configuration filenames, improving flexibility in processor instantiation.
- Refactored the loading of pretrained processors to utilize the new configuration options.

* refactor(factory): Clean up imports in factory.py

- Removed unused import of IdentityProcessor to streamline the code.

* feat(migrate): Extend load_model_from_hub to include train configuration

- Updated load_model_from_hub to return the train configuration alongside the model state_dict and config.
- Modified main function to handle the additional train configuration when loading models from both the hub and local paths.
- Adjusted dataset_repo_id extraction to utilize the train configuration for improved accuracy.

* refactor(record): Rename processor parameters and update processing logic

- Renamed `processor` to `preprocessor` and added `postprocessor` parameter for clarity.
- Updated the `record_loop` and `predict_action` functions to utilize the new preprocessor and postprocessor, enhancing the processing flow.
- Ensured compatibility with existing functionality while improving code readability.

* feat(batch_processor): Add task field processing to ToBatchProcessor

- Enhanced ToBatchProcessor to wrap string tasks in a list, adding batch dimensions for compatibility with model inference.
- Implemented a new method for processing complementary data, ensuring that task values are correctly handled as either strings or lists of strings.
- Added comprehensive unit tests to validate task processing, including edge cases and in-place mutation of complementary data.

* feat(normalization): Implement IDENTITY mode for normalization and unnormalization

- Enhanced NormalizerProcessor and UnnormalizerProcessor to support IDENTITY mode, allowing features to bypass normalization when specified.
- Updated processing logic to check normalization modes and handle missing statistics gracefully.
- Added comprehensive unit tests to validate IDENTITY mode functionality for both observations and actions, ensuring correct behavior across various scenarios.
- Improved error handling for unsupported normalization modes.

* fix(rebase): remove residual normalization layer:

* refactor(diffusion): remove normalization layer from input processing

* Add debug + calib

* cleanup

* Add pipeline

* fix int

* Add record example

* nit

* Add feature contract to pipelinestep and pipeline

* Add tests

* Add processor tests

* PR feedback

* encorperate pr feedback

* type in doc

* oops

* cleaned up steps and integrated pipeline with feature_contract

* refactor steps and robot to pipeline

* cleanup pipeline

* cleanup code further

* make it run

* feat(processors): Introduce processors for various policy types

- Added `make_processor` function to create processor instances for different policy types, including `tdmpc`, `diffusion`, `act`, `vqbet`, `pi0`, `pi0fast`, `sac`, and `reward_classifier`.
- Implemented corresponding processor files for each policy type, encapsulating normalization and unnormalization steps.
- Updated existing policies to remove direct normalization dependencies, enhancing modularity and clarity.
- Enhanced test coverage to validate the integration of new processors with existing policy configurations.

* refactor(learner): Remove normalization from cached image features retrieval

- Simplified the retrieval of observation features by removing the normalization step from the `get_cached_image_features` method calls.
- This change enhances clarity and aligns with the recent updates to policy processors.

* refactor(policies): Remove unnormalization step from action predictions

- Eliminated the unnormalization of actions in both `TDMPCPolicy` and `VQBeTPolicy` classes to streamline action prediction.
- This change improves code clarity and aligns with recent updates to policy processors.

* feat(train): Integrate preprocessor into training pipeline

* refactor(train): Update preprocessor initialization to include dataset statistics

* refactor(policies): Enhance processor creation and add NaN detection hook

* feat(record): Integrate RobotProcessor into recording loop and update policy handling

- Added support for RobotProcessor in the record_loop function to enhance data processing capabilities.
- Updated the logic to reset both policy and processor when provided, ensuring proper state management.
- Modified action prediction to utilize the processor, improving the overall functionality of the recording process.
- Adjusted the save_checkpoint function to include preprocessor state saving, enhancing checkpointing capabilities.

* feat(migration): Add script for migrating policy models with normalization layers

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* feat(migrate): Enhance migration script to create preprocessor and postprocessor for policy models

- Updated the migration script to generate both a preprocessor and a postprocessor, improving the handling of normalization for training and inference.
- Added functionality to convert features to PolicyFeature objects, ensuring compatibility with the new processor architecture.
- Refined the extraction and removal of normalization statistics and layers, streamlining the migration process.
- Improved error handling for missing mandatory configuration fields during model instantiation.

* feat(migrate): Add model card generation and saving to migration script

- Implemented functionality to generate and save a model card for the migrated model, including metadata such as dataset repository ID, license, and tags.
- Enhanced the script to push the model card to the hub if requested, improving model documentation and accessibility.
- Refactored the saving process to ensure the model card is saved locally and uploaded correctly when pushing to the hub.

* feat(processor): Introduce ToBatchProcessor for handling observation batching

- Added ToBatchProcessor to ensure observations have proper batch dimensions for model processing.
- Implemented functionality to add batch dimensions to state and image observations as needed.
- Created comprehensive unit tests to validate the processor's behavior with various tensor dimensions and types.
- Ensured compatibility with existing transition keys and maintained the integrity of non-observation data.

* feat(processors): Add ToBatchProcessor to multiple policy processors

- Integrated ToBatchProcessor into various policy processors to handle observation batching.
- Updated make functions for act, diffusion, pi0, pi0fast, sac, smolvla, tdmpc, and vqbet processors to include the new batching functionality.
- Ensured consistency across all processor implementations for improved data handling.

* refactor(factory): Remove unused imports and NaN detection hook from processor creation

* feat(batch_processor): Enhance ToBatchProcessor to handle action batching

- Updated ToBatchProcessor to add batch dimensions to actions in addition to observations.
- Implemented separate methods for processing observations and actions, improving code readability.
- Added comprehensive unit tests to validate action batching functionality across various tensor dimensions and types.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* feat(factory): Enhance make_processor to support preprocessor and postprocessor configuration

- Introduced ProcessorConfigKwargs TypedDict for better type safety in processor configuration.
- Updated make_processor to accept preprocessor and postprocessor configuration filenames, improving flexibility in processor instantiation.
- Refactored the loading of pretrained processors to utilize the new configuration options.

* refactor(factory): Clean up imports in factory.py

- Removed unused import of IdentityProcessor to streamline the code.

* feat(migrate): Extend load_model_from_hub to include train configuration

- Updated load_model_from_hub to return the train configuration alongside the model state_dict and config.
- Modified main function to handle the additional train configuration when loading models from both the hub and local paths.
- Adjusted dataset_repo_id extraction to utilize the train configuration for improved accuracy.

* refactor(record): Rename processor parameters and update processing logic

- Renamed `processor` to `preprocessor` and added `postprocessor` parameter for clarity.
- Updated the `record_loop` and `predict_action` functions to utilize the new preprocessor and postprocessor, enhancing the processing flow.
- Ensured compatibility with existing functionality while improving code readability.

* feat(batch_processor): Add task field processing to ToBatchProcessor

- Enhanced ToBatchProcessor to wrap string tasks in a list, adding batch dimensions for compatibility with model inference.
- Implemented a new method for processing complementary data, ensuring that task values are correctly handled as either strings or lists of strings.
- Added comprehensive unit tests to validate task processing, including edge cases and in-place mutation of complementary data.

* feat(normalization): Implement IDENTITY mode for normalization and unnormalization

- Enhanced NormalizerProcessor and UnnormalizerProcessor to support IDENTITY mode, allowing features to bypass normalization when specified.
- Updated processing logic to check normalization modes and handle missing statistics gracefully.
- Added comprehensive unit tests to validate IDENTITY mode functionality for both observations and actions, ensuring correct behavior across various scenarios.
- Improved error handling for unsupported normalization modes.

* fix(rebase): remove residual normalization layer:

* refactor(diffusion): remove normalization layer from input processing

* refactor(normalization): Remove unused state dict transformation methods and streamline imports

- Eliminated the _transform_state_dict_keys and _load_as_safetensor methods from PI0Policy, simplifying the model loading process.
- Cleaned up imports in modeling_pi0.py by removing log_model_loading_keys and init_logging.
- Updated TDMPCPolicy and VQBeTPolicy to handle action removal from batches during offline evaluation.
- Introduced hotswap_stats function in normalize_processor.py to update normalization statistics dynamically, with corresponding tests to ensure functionality.

* refactor(normalization): Clean up imports in normalize_processor.py

* feat(batch_processor): Add feature_contract method to ToBatchProcessor

- Introduced feature_contract method that returns features without modification, maintaining the no-op behavior of the processor.
- This addition enhances the flexibility of the ToBatchProcessor for future feature processing needs.

* fix(dependencies): Update transformers dependency constraint to allow only versions up to 4.52.0

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* feat(tokenizer): Introduce TokenizerProcessor for text tokenization

- Added TokenizerProcessor class to handle tokenization of task strings using Hugging Face's AutoTokenizer.
- Supports both string and list inputs, with customizable parameters for task key, output key, and tokenization settings.
- Implemented comprehensive unit tests to validate functionality, including handling of various input scenarios and integration with RobotProcessor.
- Updated types.py to include LANGUAGE feature type and modified __init__.py to register the new processor.

* feat(language): Enhance language processing in TokenizerProcessor

- Added OBS_LANGUAGE constant to define the observation language key.
- Updated TokenizerProcessor to store tokenized task data in the observation dictionary, ensuring compatibility with the new language feature.
- Introduced Pi0NewLineProcessor to append newlines to tasks for proper tokenization.
- Modified tests to validate the integration of language tokens and attention masks in the observation structure.

* feat(tokenizer): Add padding configuration to TokenizerProcessor

- Introduced `padding_side` parameter to the TokenizerProcessor for customizable padding direction.
- Updated the `make_pi0_processor` function to include the new padding configuration.
- Enhanced unit tests to validate the functionality of the `padding_side` parameter in various scenarios.

* feat(processor): Add state management methods to Pi0NewLineProcessor

* feat(normalization): Track normalization and unnormalization info in complementary data

- Updated NormalizerProcessor and UnnormalizerProcessor to accept additional parameters for tracking normalization modes.
- Enhanced the __call__ methods to store normalization and unnormalization information in the complementary data of transitions.
- Added unit tests to verify the correct tracking of normalization info, including scenarios with missing stats and selective normalization keys.

* feat(factory): Add preprocessor and postprocessor overrides to ProcessorConfigKwargs

- Updated ProcessorConfigKwargs to include optional overrides for preprocessor and postprocessor configurations.
- Enhanced the make_processor function to utilize the new overrides, allowing for more flexible processor initialization.

* feat(processors): Integrate RenameProcessor into various processor configurations

- Added RenameProcessor to the input steps of multiple processor functions, including make_act_processor, make_diffusion_processor, make_pi0_processor, make_sac_processor, make_tdmpc_processor, make_vqbet_processor, and make_smolvla_processor.
- Consolidated normalization features from input and output into a single NormalizerProcessor for improved efficiency.
- Updated the input steps to ensure compatibility with the new RenameProcessor integration.

* Do some todos and cleanup

* change feature_contract to dataset_features

* use one method for conversion pipeline output to add_frame dict and use base processors where possible

* Add back in and use record_loop

* update todo

* rename to_dataset_frame

* feat(smolvla): Refactor language processing and introduce new line processor (#1658)

- Removed the prepare_language method and directly accessed language tokens and masks from the batch using the OBS_LANGUAGE constant.
- Added SmolVLANewLineProcessor to ensure tasks end with a newline, enhancing tokenization compatibility.
- Updated the make_smolvla_processor function to include the new line processor and tokenizer processor for improved input handling.

* feat(processors): Integrate DeviceProcessor into multiple processor configurations

- Added DeviceProcessor to the input and output steps of various processor functions, including make_act_processor, make_diffusion_processor, make_pi0_processor, make_pi0fast_processor, make_sac_processor, make_tdmpc_processor, make_vqbet_processor, and make_smolvla_processor.
- Enhanced the DeviceProcessor class with state management methods and ensured compatibility with existing processor pipelines.
- Introduced unit tests for DeviceProcessor to validate functionality across different scenarios, including CPU and CUDA operations.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* fix

* fix reference frame

* refactor(pipeline): Remove to() method for device management

- Eliminated the to() method from RobotProcessor, which was responsible for moving tensor states to specified devices.
- Removed associated unit tests that validated the functionality of the to() method across various scenarios.
- Streamlined the pipeline code by focusing on other device management strategies.

* feat(processor): Enhance DeviceProcessor with float dtype conversion

- Added support for optional float dtype conversion in DeviceProcessor, allowing tensors to be converted to specified floating-point types while preserving non-float types.
- Implemented validation for float dtype input and updated the processor's configuration methods to include float dtype.
- Refactored tensor processing logic to streamline device movement and dtype conversion.
- Introduced comprehensive unit tests to validate the new float dtype functionality across various scenarios.

* update data visualization

* update teleop example

* fix record bugs

* Add replay

* Not code

* feature(pipeline): port tokenizer pipeline for VLA (#1645)

* feat(tokenizer): Introduce TokenizerProcessor for text tokenization

- Added TokenizerProcessor class to handle tokenization of task strings using Hugging Face's AutoTokenizer.
- Supports both string and list inputs, with customizable parameters for task key, output key, and tokenization settings.
- Implemented comprehensive unit tests to validate functionality, including handling of various input scenarios and integration with RobotProcessor.
- Updated types.py to include LANGUAGE feature type and modified __init__.py to register the new processor.

* feat(language): Enhance language processing in TokenizerProcessor

- Added OBS_LANGUAGE constant to define the observation language key.
- Updated TokenizerProcessor to store tokenized task data in the observation dictionary, ensuring compatibility with the new language feature.
- Introduced Pi0NewLineProcessor to append newlines to tasks for proper tokenization.
- Modified tests to validate the integration of language tokens and attention masks in the observation structure.

* feat(tokenizer): Add padding configuration to TokenizerProcessor

- Introduced `padding_side` parameter to the TokenizerProcessor for customizable padding direction.
- Updated the `make_pi0_processor` function to include the new padding configuration.
- Enhanced unit tests to validate the functionality of the `padding_side` parameter in various scenarios.

* feat(processor): Add state management methods to Pi0NewLineProcessor

* feat(normalization): Track normalization and unnormalization info in complementary data

- Updated NormalizerProcessor and UnnormalizerProcessor to accept additional parameters for tracking normalization modes.
- Enhanced the __call__ methods to store normalization and unnormalization information in the complementary data of transitions.
- Added unit tests to verify the correct tracking of normalization info, including scenarios with missing stats and selective normalization keys.

* feat(factory): Add preprocessor and postprocessor overrides to ProcessorConfigKwargs

- Updated ProcessorConfigKwargs to include optional overrides for preprocessor and postprocessor configurations.
- Enhanced the make_processor function to utilize the new overrides, allowing for more flexible processor initialization.

* feat(processors): Integrate RenameProcessor into various processor configurations

- Added RenameProcessor to the input steps of multiple processor functions, including make_act_processor, make_diffusion_processor, make_pi0_processor, make_sac_processor, make_tdmpc_processor, make_vqbet_processor, and make_smolvla_processor.
- Consolidated normalization features from input and output into a single NormalizerProcessor for improved efficiency.
- Updated the input steps to ensure compatibility with the new RenameProcessor integration.

* feat(smolvla): Refactor language processing and introduce new line processor (#1658)

- Removed the prepare_language method and directly accessed language tokens and masks from the batch using the OBS_LANGUAGE constant.
- Added SmolVLANewLineProcessor to ensure tasks end with a newline, enhancing tokenization compatibility.
- Updated the make_smolvla_processor function to include the new line processor and tokenizer processor for improved input handling.

* feture(policies): add device processor (#1659)

* feat(processors): Integrate DeviceProcessor into multiple processor configurations

- Added DeviceProcessor to the input and output steps of various processor functions, including make_act_processor, make_diffusion_processor, make_pi0_processor, make_pi0fast_processor, make_sac_processor, make_tdmpc_processor, make_vqbet_processor, and make_smolvla_processor.
- Enhanced the DeviceProcessor class with state management methods and ensured compatibility with existing processor pipelines.
- Introduced unit tests for DeviceProcessor to validate functionality across different scenarios, including CPU and CUDA operations.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* refactor(pipeline): Remove to() method for device management

- Eliminated the to() method from RobotProcessor, which was responsible for moving tensor states to specified devices.
- Removed associated unit tests that validated the functionality of the to() method across various scenarios.
- Streamlined the pipeline code by focusing on other device management strategies.

* feat(processor): Enhance DeviceProcessor with float dtype conversion

- Added support for optional float dtype conversion in DeviceProcessor, allowing tensors to be converted to specified floating-point types while preserving non-float types.
- Implemented validation for float dtype input and updated the processor's configuration methods to include float dtype.
- Refactored tensor processing logic to streamline device movement and dtype conversion.
- Introduced comprehensive unit tests to validate the new float dtype functionality across various scenarios.

* feat(policies): Add new line processors and update module exports

* feat(processor): Enhance batch and device processors to handle index and task_index fields

- Added logic to ToBatchProcessor for unsqueezing 0D tensors for index and task_index fields, ensuring they are processed as 1D tensors.
- Updated DeviceProcessor to process index and task_index fields in complementary data, preserving their tensor types and ensuring non-tensor fields remain unchanged.
- Enhanced unit tests to validate the correct handling of index and task_index fields across various scenarios, including device compatibility and dtype preservation.

* Add eval script

* fix `q_curr` in InverseKinematicsEEToJoints to the IK solution

* feat(processors): Introduce processors for various policy types

- Added `make_processor` function to create processor instances for different policy types, including `tdmpc`, `diffusion`, `act`, `vqbet`, `pi0`, `pi0fast`, `sac`, and `reward_classifier`.
- Implemented corresponding processor files for each policy type, encapsulating normalization and unnormalization steps.
- Updated existing policies to remove direct normalization dependencies, enhancing modularity and clarity.
- Enhanced test coverage to validate the integration of new processors with existing policy configurations.

* refactor(learner): Remove normalization from cached image features retrieval

- Simplified the retrieval of observation features by removing the normalization step from the `get_cached_image_features` method calls.
- This change enhances clarity and aligns with the recent updates to policy processors.

* refactor(policies): Remove unnormalization step from action predictions

- Eliminated the unnormalization of actions in both `TDMPCPolicy` and `VQBeTPolicy` classes to streamline action prediction.
- This change improves code clarity and aligns with recent updates to policy processors.

* feat(train): Integrate preprocessor into training pipeline

* refactor(train): Update preprocessor initialization to include dataset statistics

* refactor(policies): Enhance processor creation and add NaN detection hook

* feat(record): Integrate RobotProcessor into recording loop and update policy handling

- Added support for RobotProcessor in the record_loop function to enhance data processing capabilities.
- Updated the logic to reset both policy and processor when provided, ensuring proper state management.
- Modified action prediction to utilize the processor, improving the overall functionality of the recording process.
- Adjusted the save_checkpoint function to include preprocessor state saving, enhancing checkpointing capabilities.

* feat(migration): Add script for migrating policy models with normalization layers

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* feat(migrate): Enhance migration script to create preprocessor and postprocessor for policy models

- Updated the migration script to generate both a preprocessor and a postprocessor, improving the handling of normalization for training and inference.
- Added functionality to convert features to PolicyFeature objects, ensuring compatibility with the new processor architecture.
- Refined the extraction and removal of normalization statistics and layers, streamlining the migration process.
- Improved error handling for missing mandatory configuration fields during model instantiation.

* feat(migrate): Add model card generation and saving to migration script

- Implemented functionality to generate and save a model card for the migrated model, including metadata such as dataset repository ID, license, and tags.
- Enhanced the script to push the model card to the hub if requested, improving model documentation and accessibility.
- Refactored the saving process to ensure the model card is saved locally and uploaded correctly when pushing to the hub.

* feat(processor): Introduce ToBatchProcessor for handling observation batching

- Added ToBatchProcessor to ensure observations have proper batch dimensions for model processing.
- Implemented functionality to add batch dimensions to state and image observations as needed.
- Created comprehensive unit tests to validate the processor's behavior with various tensor dimensions and types.
- Ensured compatibility with existing transition keys and maintained the integrity of non-observation data.

* feat(processors): Add ToBatchProcessor to multiple policy processors

- Integrated ToBatchProcessor into various policy processors to handle observation batching.
- Updated make functions for act, diffusion, pi0, pi0fast, sac, smolvla, tdmpc, and vqbet processors to include the new batching functionality.
- Ensured consistency across all processor implementations for improved data handling.

* refactor(factory): Remove unused imports and NaN detection hook from processor creation

* feat(batch_processor): Enhance ToBatchProcessor to handle action batching

- Updated ToBatchProcessor to add batch dimensions to actions in addition to observations.
- Implemented separate methods for processing observations and actions, improving code readability.
- Added comprehensive unit tests to validate action batching functionality across various tensor dimensions and types.

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* feat(factory): Enhance make_processor to support preprocessor and postprocessor configuration

- Introduced ProcessorConfigKwargs TypedDict for better type safety in processor configuration.
- Updated make_processor to accept preprocessor and postprocessor configuration filenames, improving flexibility in processor instantiation.
- Refactored the loading of pretrained processors to utilize the new configuration options.

* refactor(factory): Clean up imports in factory.py

- Removed unused import of IdentityProcessor to streamline the code.

* feat(migrate): Extend load_model_from_hub to include train configuration

- Updated load_model_from_hub to return the train configuration alongside the model state_dict and config.
- Modified main function to handle the additional train configuration when loading models from both the hub and local paths.
- Adjusted dataset_repo_id extraction to utilize the train configuration for improved accuracy.

* refactor(record): Rename processor parameters and update processing logic

- Renamed `processor` to `preprocessor` and added `postprocessor` parameter for clarity.
- Updated the `record_loop` and `predict_action` functions to utilize the new preprocessor and postprocessor, enhancing the processing flow.
- Ensured compatibility with existing functionality while improving code readability.

* feat(batch_processor): Add task field processing to ToBatchProcessor

- Enhanced ToBatchProcessor to wrap string tasks in a list, adding batch dimensions for compatibility with model inference.
- Implemented a new method for processing complementary data, ensuring that task values are correctly handled as either strings or lists of strings.
- Added comprehensive unit tests to validate task processing, including edge cases and in-place mutation of complementary data.

* feat(normalization): Implement IDENTITY mode for normalization and unnormalization

- Enhanced NormalizerProcessor and UnnormalizerProcessor to support IDENTITY mode, allowing features to bypass normalization when specified.
- Updated processing logic to check normalization modes and handle missing statistics gracefully.
- Added comprehensive unit tests to validate IDENTITY mode functionality for both observations and actions, ensuring correct behavior across various scenarios.
- Improved error handling for unsupported normalization modes.

* fix(rebase): remove residual normalization layer:

* refactor(diffusion): remove normalization layer from input processing

* refactor(normalization): Remove unused state dict transformation methods and streamline imports

- Eliminated the _transform_state_dict_keys and _load_as_safetensor methods from PI0Policy, simplifying the model loading process.
- Cleaned up imports in modeling_pi0.py by removing log_model_loading_keys and init_logging.
- Updated TDMPCPolicy and VQBeTPolicy to handle action removal from batches during offline evaluation.
- Introduced hotswap_stats function in normalize_processor.py to update normalization statistics dynamically, with corresponding tests to ensure functionality.

* refactor(normalization): Clean up imports in normalize_processor.py

* feat(batch_processor): Add feature_contract method to ToBatchProcessor

- Introduced feature_contract method that returns features without modification, maintaining the no-op behavior of the processor.
- This addition enhances the flexibility of the ToBatchProcessor for future feature processing needs.

* fix(dependencies): Update transformers dependency constraint to allow only versions up to 4.52.0

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* feature(pipeline): port tokenizer pipeline for VLA (#1645)

* feat(tokenizer): Introduce TokenizerProcessor for text tokenization

- Added TokenizerProcessor class to handle tokenization of task strings using Hugging Face's AutoTokenizer.
- Supports both string and list inputs, with customizable parameters for task key, output key, and tokenization settings.
- Implemented comprehensive unit tests to validate functionality, including handling of various input scenarios and integration with RobotProcessor.
- Updated types.py to include LANGUAGE feature type and modified __init__.py to register the new processor.

* feat(language): Enhance language processing in TokenizerProcessor

- Added OBS_LANGUAGE constant to define the observation language key.
- Updated TokenizerProcessor to store tokenized task data in the observation dictionary, ensuring compatibility with the new language feature.
- Introduced Pi0NewLineProcessor to append newlines to tasks for proper tokenization.
- Modified tests to validate the integration of language tokens and attention masks in the observation structure.

* feat(tokenizer): Add padding configuration to TokenizerProcessor

- Introduced `padding_side` parameter to the TokenizerProcessor for customizable padding direction.
- Updated the `make_pi0_processor` function to include the new padding configuration.
- Enhanced unit tests to validate the functionality of the `padding_side` parameter in various scenarios.

* feat(processor): Add state management methods to Pi0NewLineProcessor

* feat(normalization): Track normalization and unnormalization info in complementary data

- Updated NormalizerProcessor and UnnormalizerProcessor to accept additional parameters for tracking normalization modes.
- Enhanced the __call__ methods to store normalization and unnormalization information in the complementary data of transitions.
- Added unit tests to verify the correct tracking of normalization info, including scenarios with missing stats and selective normalization keys.

* feat(factory): Add preprocessor and postprocessor overrides to ProcessorConfigKwargs

- Updated ProcessorConfigKwargs to include optional overrides for preprocessor and postprocessor configurations.
- Enhanced the make_processor function to utilize the new overrides, allowing for more flexible processor initialization.

* feat(processors): Integrate RenameProcessor into various processor configurations

- Added RenameProcessor to the input steps of multiple processor functions, including make_act_processor, make_diffusion_processor, make_pi0_processor, make_sac_processor, make_tdmpc_processor, make_vqbet_processor, and make_smolvla_processor.
- Consolidated normalization features from input and output into a single NormalizerProcessor for improved efficiency.
- Updated the input steps to ensure compatibility with the new RenameProcessor integration.

* feat(smolvla): Refactor language processing and introduce new line processor (#1658)

- Removed the prepare_language method and directly accessed language tokens and masks from the batch using the OBS_LANGUAGE constant.
- Added SmolVLANewLineProcessor to ensure tasks end with a newline, enhancing tokenization compatibility.
- Updated the make_smolvla_processor function to include the new line processor and tokenizer processor for improved input handling.

* feture(policies): add device processor (#1659)

* feat(processors): Integrate DeviceProcessor into multiple processor configurations

- Added DeviceProcessor to the input and output steps of various processor functions, including make_act_processor, make_diffusion_processor, make_pi0_processor, make_pi0fast_processor, make_sac_processor, make_tdmpc_processor, make_vqbet_processor, and make_smolvla_processor.
- Enhanced the DeviceProcessor class with state management methods and ensured compatibility with existing processor pipelines.
- Introduced unit tests for DeviceProcessor to validate functionality across different scenarios, including CPU and CUDA operations.

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* refactor(pipeline): Remove to() method for device management

- Eliminated the to() method from RobotProcessor, which was responsible for moving tensor states to specified devices.
- Removed associated unit tests that validated the functionality of the to() method across various scenarios.
- Streamlined the pipeline code by focusing on other device management strategies.

* feat(processor): Enhance DeviceProcessor with float dtype conversion

- Added support for optional float dtype conversion in DeviceProcessor, allowing tensors to be converted to specified floating-point types while preserving non-float types.
- Implemented validation for float dtype input and updated the processor's configuration methods to include float dtype.
- Refactored tensor processing logic to streamline device movement and dtype conversion.
- Introduced comprehensive unit tests to validate the new float dtype functionality across various scenarios.

* feat(policies): Add new line processors and update module exports

* feat(processor): Enhance batch and device processors to handle index and task_index fields

- Added logic to ToBatchProcessor for unsqueezing 0D tensors for index and task_index fields, ensuring they are processed as 1D tensors.
- Updated DeviceProcessor to process index and task_index fields in complementary data, preserving their tensor types and ensuring non-tensor fields remain unchanged.
- Enhanced unit tests to validate the correct handling of index and task_index fields across various scenarios, including device compatibility and dtype preservation.

* refactor(processors): Standardize processor naming conventions

- Updated processor names across various files to use a consistent "robot_preprocessor" and "robot_postprocessor" format.
- Modified the make_processor functions in factory, act, diffusion, pi0, pi0fast, sac, smolvla, tdmpc, and vqbet to reflect the new naming scheme.
- Enhanced the pipeline configuration to align with the updated processor names, improving clarity and maintainability.

* refactor(factory): Update processor configuration and type hints

- Changed return type of get_policy_class to type[PreTrainedPolicy] for improved type safety.
- Enhanced make_processor function to utilize dataset_stats in processor creation for better flexibility.
- Updated ProcessorConfigKwargs to include dataset_stats, allowing for more comprehensive processor configurations.
- Streamlined processor initialization by removing unnecessary kwargs and ensuring clarity in processor type handling.

* Fix eval and android gripper

* add some tests

* refactor(factory, pi0fast): Update processor function names and parameters

- Renamed make_pi0_processor to make_pi0fast_processor for clarity and consistency.
- Updated parameter names in the factory's make_processor function to use pretrained_model_name_or_path instead of source, enhancing readability and alignment with naming conventions.

* fix(train.py) push postprocessor with preprocessor
- Add preprocesser policy overrides for device and rename_map
- Add rename_map to DatasetRecordConfig (record.py)

* Cleanup pr

* fix more git diff pr issues

* add path as type in save_pretrained

* small nit

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* rename test file

* fix: make dataset_features/feature_contract is optional

* fix tests

* Encorperate pr feedback

* clean up record.py

* add ascii art, fix normal record

* remove merge issues

* fix merge

* remove features

* Add feedback PR

* fix last 4 tests

* remove features check

* rename to transform_features

* add transform_features

* fix lekiwi eval and update eval api example

---------

Signed-off-by: Adil Zouitine <adilzouitinegm@gmail.com>
Signed-off-by: Pepijn <138571049+pkooij@users.noreply.github.com>
Co-authored-by: Adil Zouitine <adilzouitinegm@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Simon Alibert <75076266+aliberts@users.noreply.github.com>
Co-authored-by: Michel Aractingi <michel.aractingi@huggingface.co>

* refactor(TokenizerProcessor): improve dependency handling and observation management

- Updated TokenizerProcessor to conditionally import AutoTokenizer based on the availability of the transformers library, enhancing flexibility.
- Modified tokenizer attribute type to Any to accommodate scenarios where transformers may not be installed.
- Improved observation handling by using a more concise approach to manage the transition dictionary, ensuring compatibility with existing data structures.
- Added error handling for missing transformers library, providing clear guidance for users on installation requirements.

* feat(dependencies): Add scipy as a required dependency

- Included `scipy>=1.15.2` in the project dependencies to enhance functionality and support for scientific computing tasks.

* feat(policies): convert save_policy_to_safetensors with pipeline

* refactor(normalization): remove Normalize and Unnormalize classes

- Deleted the Normalize and Unnormalize classes from the normalization module to streamline the codebase.
- Updated tests to ensure compatibility with the removal of these classes, focusing on the new NormalizerProcessor and UnnormalizerProcessor implementations.
- Enhanced the handling of normalization statistics and improved overall code clarity.

* refactor(factory): streamline processor loading by removing unused comments

- Removed commented-out code related to loading pretrained processors in the make_processor function.
- This change enhances code clarity and maintains focus on the current implementation.

* feat(DeviceProcessor): Enhance tensor processing with device detection and float dtype conversion

- Improved the _process_tensor method to preserve GPU placement for tensors already on a GPU, facilitating multi-GPU training scenarios.
- Introduced a new _detect_device method in TokenizerProcessor to ensure tokenized tensors match the device of existing tensors in transitions.
- Added comprehensive unit tests to validate the functionality of device detection and float dtype conversion across various scenarios.

* feat(tests): Add comprehensive tests for various policy processors

- Introduced new test files for ACT, Classifier, Diffusion, PI0, SAC, SmolVLA, TDMPC, and VQBeT policy processors.
- Each test file includes unit tests to validate functionality, including handling of batch sizes, device management, and data type conversions.
- Enhanced test coverage to ensure robustness and reliability of processor implementations across different scenarios.

* refactor(train): Remove unnecessary tensor device handling in training loop

* Refactor`gym_manipulator.py` using the universal pipeline (#1650)

* Migrate gym_manipulator to use the pipeline
Added get_teleop_events function to capture relevant events from teleop devices unrelated to actions

* Added the capability to record a dataset

* Added the replay functionality with the pipeline

* Refactored `actor.py` to use the pipeline

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* RL works at this commit - fixed actor.py and bugs in gym_manipulator

* change folder structure to reduce the size of gym_manip

* Refactored hilserl config

* Remove dataset and mode from HilSerlEnvConfig to a GymManipulatorConfig to reduce verbose of configs during training

* format docs

* removed get_teleop_events from abc

* Refactor environment configuration and processing pipeline for GymHIL support. Removed device attribute from HILSerlRobotEnvConfig, added DummyTeleopDevice for simulation, and updated processor creation to accommodate GymHIL environments.

* Improved typing for HILRobotEnv config and GymManipulator config

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* Migrated `gym_manipulator` to use a more modular structure similar to phone teleop

* Refactor gripper handling and transition processing in HIL and robot kinematic processors

- Updated gripper position handling to use a consistent key format across processors
- Improved the EEReferenceAndDelta class to handle reference joint positions.
- Added support for discrete gripper actions in the GripperVelocityToJoint processor.
- Refactored the gym manipulator to improve modularity and clarity in processing steps.

* Added delta_action_processor mapping wrapper

* Added missing file delta_action_processor and improved imports in `gym_manipulator`

* nit

* Added missing file joint_observation_processor

* Enhance processing architecture with new teleoperation processors

- Introduced `AddTeleopActionAsComplimentaryData` and `AddTeleopEventsAsInfo` for integrating teleoperator actions and events into transitions.
- Added `Torch2NumpyActionProcessor` and `Numpy2TorchActionProcessor` for seamless conversion between PyTorch tensors and NumPy arrays.
- Updated `__init__.py` to include new processors in module exports, improving modularity and clarity in the processing pipeline.
- GymHIL is now fully supported with HIL using the pipeline

* Refactor configuration structure for gym_hil integration

- Renamed sections for better readability, such as changing "Gym Wrappers Configuration" to "Processor Configuration."
- Enhanced documentation with clear examples for dataset collection and policy evaluation configurations.

* Enhance reset configuration and teleoperation event handling

- Added `terminate_on_success` parameter to `ResetConfig` and `InterventionActionProcessor` for controlling episode termination behavior upon success detection.
- Updated documentation to clarify the impact of `terminate_on_success` on data collection for reward classifier training.
- Refactored teleoperation event handling to use `TeleopEvents` constants for improved readability and maintainability across various modules.

* fix(keyboard teleop), delta action keys

* Added transform features and feature contract

* Added transform features for image crop

* Enum for TeleopEvents

* Update tranform_features delta action proc

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

* Remove HILEnvConfig references

* chore(processor): Add default names for preprocessor and postprocessor in constants

- Introduced `PREPROCESSOR_DEFAULT_NAME` and `POSTPROCESSOR_DEFAULT_NAME` constants for consistent naming across various processor implementations.
- Updated processor creation in multiple policy files to utilize these constants, enhancing code readability and maintainability.
- Modified the training script to load and save the preprocessor and postprocessor using the new constants.

* feat(processor): multiple improvements to the pipeline porting (#1749)

* [Port codebase pipeline] General fixes for RL and scripts (#1748)

* Refactor dataset configuration in documentation and codebase

- Updated dataset configuration keys from `dataset_root` to `root` and `num_episodes` to `num_episodes_to_record` for consistency.
- Adjusted replay episode handling by renaming `episode` to `replay_episode`.
- Enhanced documentation
- added specific processor to transform from policy actions to delta actions

* Added Robot action to tensor processor
Added new processor script for dealing with gym specific action processing

* removed RobotAction2Tensor processor; imrpoved choosing observations in actor

* nit in delta action

* added missing reset functions to kinematics

* Adapt teleoperate and replay to pipeline similar to record

* refactor(processors): move to inheritance (#1750)

* fix(teleoperator): improvements phone implementation (#1752)

* fix(teleoperator): protect shared state in phone implementation

* refactor(teleop): separate classes in phone

* fix: solve breaking changes (#1753)

* refactor(policies): multiple improvements (#1754)

* refactor(processor): simpler logic in device processor (#1755)

* refactor(processor): euclidean distance in delta action processor (#1757)

* refactor(processor): improvements to joint observations processor migration (#1758)

* refactor(processor): improvements to tokenizer migration (#1759)

* refactor(processor): improvements to tokenizer migration

* fix(tests): tokenizer tests regression from #1750

* fix(processors): fix float comparison and config in hil processors (#1760)

* chore(teleop): remove unnecessary callbacks in KeyboardEndEffectorTeleop (#1761)

* refactor(processor): improvements normalize pipeline migration (#1756)

* refactor(processor): several improvements normalize processor step

* refactor(processor): more improvements normalize processor

* refactor(processor): more changes to normalizer

* refactor(processor): take a different approach to DRY

* refactor(processor): final design

* chore(record): revert comment and continue deleted (#1764)

* refactor(examples): pipeline phone examples (#1769)

* refactor(examples): phone teleop + teleop script

* refactor(examples): phone replay + replay

* chore(examples): rename phone example files & folders

* feat(processor): fix improvements to the pipeline porting (#1796)

* refactor(processor): enhance tensor device handling in normalization process (#1795)

* refactor(tests): remove unsupported device detection test for complementary data (#1797)

* chore(tests): update ToBatchProcessor test (#1798)

* refactor(tests): remove in-place mutation tests for actions and complementary data in batch processor

* test(tests): add tests for action and task processing in batch processor

* add names for android and ios phone (#1799)

* use _tensor_stats in normalize processor (#1800)

* fix(normalize_processor): correct device reference for tensor epsilon handling (#1801)

* add point 5 add missing feature contracts (#1806)

* Fix PR comments 1452 (#1807)

* use key to determine image

* Address rest of PR comments

* use PolicyFeatures in transform_features

---------

Co-authored-by: Pepijn <138571049+pkooij@users.noreply.github.com>

---------

Co-authored-by: Michel Aractingi <michel.aractingi@huggingface.co>
Co-authored-by: Adil Zouitine <adilzouitinegm@gmail.com>
Co-authored-by: Pepijn <138571049+pkooij@users.noreply.github.com>

* refactor(constants, processor): standardize action and observation keys across multiple files (#1808)

- Added new constants for truncated and done states in constants.py.
- Updated references to action and observation keys in pipeline_features.py, converters.py, hil_processor.py, tokenizer_processor.py, and robot_kinematic_processor.py to use the new constants for improved readability and maintainability.

* refactor(processor): improve processor pipeline typing with generic type (#1810)

* refactor(processor): introduce generic type for to_output

- Always return `TOutput`
- Remove `_prepare_transition`, so `__call__` now always returns `TOutput`
- Update tests accordingly
- This refactor paves the way for adding settings for `to_transition` and `to_output` in `make_processor` and the post-processor

* refactor(processor): consolidate ProcessorKwargs usage across policies

- Removed the ProcessorTypes module and integrated ProcessorKwargs directly into the processor pipeline.
- Updated multiple policy files to utilize the new ProcessorKwargs structure for preprocessor and postprocessor arguments.
- Simplified the handling of processor kwargs by initializing them to empty dictionaries when not provided.

* refactor(converters): implement unified tensor conversion function (#1830)

- Introduced `to_tensor` function using `singledispatch` to handle various input types, including scalars, arrays, and dictionaries, converting them to PyTorch tensors.
- Replaced previous tensor conversion logic in `gym_action_processor`, `normalize_processor`, and `test_converters` with the new `to_tensor` function for improved readability and maintainability.
- Updated tests to cover new functionality and ensure correct tensor conversion behavior.

* Revert "refactor(converters): implement unified tensor conversion function (#…" (#1840)

This reverts commit a837685bf8.

* refactor(converters): implement unified tensor conversion function (#1841)

- Introduced `to_tensor` function using `singledispatch` to handle various input types, including scalars, arrays, and dictionaries, converting them to PyTorch tensors.
- Replaced previous tensor conversion logic in `gym_action_processor`, `normalize_processor`, and `test_converters` with the new `to_tensor` function for improved readability and maintainability.
- Updated tests to cover new functionality and ensure correct tensor conversion behavior.

Co-authored-by: AdilZouitine <adilzouitinegm@gmail.com>

* refactor(converters): gather converters and refactor the logic (#1833)

* refactor(converters): move batch transition functions to converters module

- Moved `_default_batch_to_transition` and `_default_transition_to_batch` functions from `pipeline.py` to `converters.py` for better organization and separation of concerns.
- Updated references in `RobotProcessor` to use the new location of these functions.
- Added tests to ensure correct functionality of the transition functions, including handling of index and task_index fields.
- Removed redundant tests from `pipeline.py` to streamline the test suite.

* refactor(processor): reorganize EnvTransition and TransitionKey definitions

- Moved `EnvTransition` and `TransitionKey` classes from `pipeline.py` to a new `core.py` module for better structure and maintainability.
- Updated import statements across relevant modules to reflect the new location of these definitions, ensuring consistent access throughout the codebase.

* refactor(converters): rename and update dataset frame conversion functions

- Replaced `to_dataset_frame` with `transition_to_dataset_frame` for clarity and consistency in naming.
- Updated references in `record.py`, `pipeline.py`, and tests to use the new function name.
- Introduced `merge_transitions` to streamline the merging of transitions, enhancing readability and maintainability.
- Adjusted related tests to ensure correct functionality with the new naming conventions.

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* fix(processor): solve conflict artefacts

* refactor(converters): remove unused identity function and update type hints for merge_transitions

* refactor(processor): remove unused identity import and clean up gym_manipulator.py

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Steven Palma <steven.palma@huggingface.co>

* refactor(processors): add transform_features method to various processors (#1843)

* refactor(processors): update transition handling in RewardClassifierProcessor and InverseKinematicsEEToJoints (#1844)

* refactor(processors): unify import statements by consolidating pipeline imports into the main processor module (#1845)

* refactor(processors): add extended api for specialized pipelines (#1848)

* refactor(processors): enhance transform_features method across multiple processors (#1849)

* refactor(processors): enhance transform_features method across multiple processors

- Updated the transform_features method in various processors to utilize a copy of the features dictionary, ensuring immutability of the original features.
- Added handling for new feature keys and removed obsolete ones in the MapTensorToDeltaActionDict, JointVelocityProcessor, and others.
- Improved readability and maintainability by following consistent patterns in feature transformation.

* refactor(processors): standardize action and observation keys in delta_action_processor and joint_observations_processor

- Updated action and observation keys to use constants for improved readability and maintainability.
- Refactored the transform_features method in multiple processors to ensure consistent handling of feature keys.
- Enhanced error handling by raising exceptions for missing required components in action and observation processing.
- Removed obsolete code and improved overall structure for better clarity.

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* refactor(processors): remove unused import in joint_observations_processor

* refactor(processors): simplify transform_features method in delta_action_processor

* refactor(processors): streamline transform_features method in ImageCropResizeProcessor

* refactor(processors): improve error handling and streamline transform_features method in phone_processor

- Raised a ValueError for missing position and rotation in action to enhance error handling.

* refactor(processors): enhance error handling in JointVelocityProcessor

- Added a ValueError raise for missing current joint positions in the observation method to improve error handling and ensure the integrity of the transform_features method.

* refactor(processors): simplify transform_features method in robot kinematic processors

* refactor(processors): standardize action keys in phone_processor

* fix(processor): RKP feature obs -> act

---------

Signed-off-by: Adil Zouitine <adilzouitinegm@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Steven Palma <steven.palma@huggingface.co>

* chore(processor): rename RobotProcessor -> DataProcessorPipeline (#1850)

* chore(processor): rename specialized processor -> XYZProcessorStep (#1852)

* chore(processor): rename converters function names (#1853)

* chore(processor): rename to_transition_teleop_action -> action_to_transition

* chore(processor): rename to_transition_robot_observation -> observation_to_transition

* chore(processor): rename to_output_robot_action -> transition_to_robot_action

* chore(processor): add Step suffix to all processors (#1854)

* refactor(processor): rename MapDeltaActionToRobotAction and MapTensorToDeltaActionDict for consistency

* refactor(processor): rename DeviceProcessor to DeviceProcessorStep for consistency across modules

* refactor(processor): rename Torch2NumpyActionProcessor to Torch2NumpyActionProcessorStep for consistency

* refactor(processor): rename Numpy2TorchActionProcessor to Numpy2TorchActionProcessorStep for consistency

* refactor(processor): rename AddTeleopActionAsComplimentaryData to AddTeleopActionAsComplimentaryDataStep for consistency

* refactor(processor): rename ImageCropResizeProcessor and AddTeleopEventsAsInfo for consistency

* refactor(processor): rename TimeLimitProcessor to TimeLimitProcessorStep for consistency

* refactor(processor): rename GripperPenaltyProcessor to GripperPenaltyProcessorStep for consistency

* refactor(processor): rename InterventionActionProcessor to InterventionActionProcessorStep for consistency

* refactor(processor): rename RewardClassifierProcessor to RewardClassifierProcessorStep for consistency

* refactor(processor): rename JointVelocityProcessor to JointVelocityProcessorStep for consistency

* refactor(processor): rename MotorCurrentProcessor to MotorCurrentProcessorStep for consistency

* refactor(processor): rename NormalizerProcessor and UnnormalizerProcessor to NormalizerProcessorStep and UnnormalizerProcessorStep for consistency

* refactor(processor): rename VanillaObservationProcessor to VanillaObservationProcessorStep for consistency

* refactor(processor): rename RenameProcessor to RenameProcessorStep for consistency

* refactor(processor): rename TokenizerProcessor to TokenizerProcessorStep for consistency

* refactor(processor): rename ToBatchProcessor to AddBatchDimensionProcessorStep for consistency

* refactor(processor): update config file name in test for RenameProcessorStep consistency

* refactor(processor): rename internal tokenizer variable for clarity (#1855)

- Changed the internal tokenizer variable name from `_tokenizer` to `input_tokenizer` for improved readability and consistency.
- Updated references throughout the class to reflect the new variable name.

* chore(processor): rename merge_features -> combine_feature_dicts (#1856)

* refactor(processor): rename internal device variable for clarity (#1857)

- Changed the internal device variable from `_device` to `tensor_device` for improved readability and consistency.
- Updated references throughout the class to reflect the new variable name.

* chore(processor): rename teleop_phone variable names (#1858)

* chore(processor): add type alias RobotProcessorPipeline and PolicyProcessorPipeline (#1859)

* feat(processor): introduce PolicyProcessorPipeline and RobotProcessorPipeline as type aliases for DataProcessorPipeline

- Added PolicyProcessorPipeline and RobotProcessorPipeline type aliases to enhance clarity and maintainability in the processor module.
- Updated the __all__ list to include the new pipelines for better module export consistency.

* refactor(processor): replace DataProcessorPipeline with PolicyProcessorPipeline across multiple modules

- Updated all instances of DataProcessorPipeline to PolicyProcessorPipeline in various processor files for consistency and clarity.
- Adjusted function signatures to reflect the new pipeline type, enhancing maintainability and readability.

* refactor(processor): update hotswap_stats function to use PolicyProcessorPipeline

- Changed the parameter name from robot_processor to policy_processor for clarity.
- Ensured consistency with recent updates to the processor module by reflecting the new pipeline type in the function signature.

* refactor(processor): replace DataProcessorPipeline with PolicyProcessorPipeline in migrate_policy_normalization.py

- Updated the preprocessor and postprocessor to use PolicyProcessorPipeline for consistency with recent changes in the processor module.
- Enhanced clarity and maintainability by aligning with the new pipeline structure.

* refactor(processor): update hotswap_stats to use PolicyProcessorPipeline

- Changed the parameter type in hotswap_stats from DataProcessorPipeline to PolicyProcessorPipeline for consistency with recent updates.
- Enhanced clarity by updating the function documentation to reflect the new pipeline type.

* refactor(processor): replace DataProcessorPipeline with RobotProcessorPipeline across multiple files

- Updated instances of DataProcessorPipeline to RobotProcessorPipeline in evaluate.py, record.py, replay.py, teleoperate.py, and other relevant files for consistency and clarity.
- Adjusted function signatures and variable types to reflect the new pipeline structure, enhancing maintainability and readability.

* refactor(processor): enforce config_filename requirement for HF Hub loading (#1860)

- Updated the DataProcessorPipeline to require a specific config_filename when loading from Hugging Face Hub, enhancing clarity and preventing errors.
- Simplified local path checks and improved error handling for invalid paths.
- Adjusted tests to reflect the new requirement and ensure proper error handling for various loading scenarios.

* feat(record): add transition features to dataset and handle scalar vs array formatting in converters (#1861)

- Introduced new transition features (`next.reward`, `next.done`, `next.truncated`) in the dataset during recording.
- Updated the `transition_to_dataset_frame` function to handle scalar values correctly, ensuring compatibility with expected array formats for reward, done, and truncated features.

* refactor(pipeline): enforce ProcessorStep inheritance for pipeline steps (#1862)

- Updated the DataProcessorPipeline to require that all steps inherit from ProcessorStep, enhancing type safety and clarity.
- Adjusted tests to utilize a MockTokenizerProcessorStep that adheres to the ProcessorStep interface, ensuring consistent behavior across tests.
- Refactored various mock step classes in tests to inherit from ProcessorStep for improved consistency and maintainability.

* refactor(dependencies): remove scipy dependency and introduce custom rotation utilities (#1863)

- Removed the scipy dependency from the project to streamline requirements.
- Added a new `rotation.py` module containing a custom `Rotation` class that replicates essential functionalities of `scipy.spatial.transform.Rotation`, allowing for rotation vector, matrix, and quaternion conversions without external dependencies.
- Updated the `robot_kinematic_processor.py` to utilize the new custom rotation utilities.

* feat(teleoperation): introduce HasTeleopEvents protocol and enhance teleop event handling (#1866)

- Added the HasTeleopEvents protocol to define a standard for teleoperators that provide control events.
- Implemented a runtime check to ensure teleoperators implement the get_teleop_events() method.
- Updated AddTeleopEventsAsInfoStep to utilize the new protocol, enhancing compatibility with custom teleoperators.
- Improved documentation for clarity on teleoperation event extraction and compatibility with built-in teleoperators.

* fix(deps): use in-house rotation utils over scipy throughout the codebase

* refactor(constants): rename preprocessor and postprocessor constants for clarity (#1868)

- Updated constant names from PREPROCESSOR_DEFAULT_NAME and POSTPROCESSOR_DEFAULT_NAME to POLICY_PREPROCESSOR_DEFAULT_NAME and POLICY_POSTPROCESSOR_DEFAULT_NAME for better context.
- Adjusted references across multiple files to use the new constant names, ensuring consistency in the codebase.

* refactor(tests): update processor test assertions to reflect new preprocessor and postprocessor names (#1869)

- Changed assertions in multiple processor test files to verify the updated names from "robot_preprocessor" and "robot_postprocessor" to "policy_preprocessor" and "policy_postprocessor" for consistency with recent refactoring.

* refactor(utils): simplify log_rerun_data function (#1864)

* refactor(logging): enhance log_rerun_data to handle observation and action separately

- Updated the `log_rerun_data` function to accept and log observation and action data more clearly, improving readability and maintainability.
- Refactored the `record_loop` and `teleop_loop` functions to extract and pass observation and action data to `log_rerun_data`, ensuring consistent logging format.

* refactor(tests): update test_log_rerun_data to align with log_rerun_data changes

- Modified test cases in `test_visualization_utils.py` to extract and pass observation and action data separately to `log_rerun_data`, improving clarity and consistency with recent function updates.
- Ensured that the tests reflect the new structure of `log_rerun_data` for better maintainability.

* refactor(processors): simplify calls to log_rerun + replace lambda functions with identity_transition

---------

Co-authored-by: Steven Palma <steven.palma@huggingface.co>

* fix(processor): recover type inference for use of processors (#1873)

* refactor(processors): Improve Normalization Processor Performance and Device/Dtype Adaptability (#1880)

* refactor(processors): reorder processor steps for consistency across implementations

- Updated the order of processor steps in multiple files to ensure consistency, placing AddBatchDimensionProcessorStep and DeviceProcessorStep before NormalizerProcessorStep.
- Adjusted related test assertions to reflect the new order of steps in the preprocessor, enhancing clarity and maintainability.

* refactor(normalization): remove dtype specification in tensor conversion for adaptation logic

- Updated tensor conversion in the _NormalizationMixin class to remove explicit dtype specification, allowing for automatic adaptation of tensor types.
- Adjusted related tests to ensure proper functionality with the new tensor conversion logic, verifying that normalizers adapt correctly to input types.

* chore(docs): update doctrines pipeline files (#1872)

* docs(processor): update docstrings batch_processor

* docs(processor): update docstrings device_processor

* docs(processor): update docstrings tokenizer_processor

* update docstrings processor_act

* update docstrings for pipeline_features

* update docstrings for utils

* update docstring for processor_diffusion

* update docstrings factory

* add docstrings to pi0 processor

* add docstring to pi0fast processor

* add docstring classifier processor

* add docstring to sac processor

* add docstring smolvla processor

* add docstring to tdmpc processor

* add docstring to vqbet processor

* add docstrings to converters

* add docstrings for delta_action_processor

* add docstring to gym action processor

* update hil processor

* add docstring to joint obs processor

* add docstring to migrate_normalize_processor

* update docstrings normalize processor

* update docstring normalize processor

* update docstrings observation processor

* update docstrings rename_processor

* add docstrings robot_kinematic_processor

* cleanup rl comments

* add docstring to train.py

* add docstring to teleoperate.py

* add docstrings to phone_processor.py

* add docstrings to teleop_phone.py

* add docstrings to control_utils.py

* add docstrings to visualization_utils.py

---------

Co-authored-by: Pepijn <pepijn@huggingface.co>

* refactor(eval): integrate preprocessor and postprocessor into rollout and eval_policy functions (#1900)

* refactor(eval): integrate preprocessor and postprocessor into rollout and eval_policy functions

- Updated the `rollout` and `eval_policy` functions to accept preprocessor and postprocessor parameters, enhancing the flexibility of the evaluation pipeline.
- Adjusted the implementation to apply preprocessing and postprocessing steps during policy evaluation, improving the overall data handling and processing flow.

* refactor(eval): remove redundant observation device conversion in rollout function

- Eliminated unnecessary device conversion for the observation dictionary within the `rollout` function, streamlining the code and enhancing readability.
- This change simplifies the observation handling process, aligning with the preference for clearer solutions.

* debug

* refactor(utils): enhance task handling in add_envs_task function

- Improved the `add_envs_task` function to validate the output of `task_description` and `task` calls, ensuring they return lists of strings.
- Removed the use of `else` statement for environments without language instructions, simplifying the logic and enhancing readability.
- Streamlined the observation dictionary handling by ensuring consistent data types for task attributes.

* refactor(converters): rename _from_tensor to from_tensor_to_numpy for clarity (#1902)

- Updated the function name from _from_tensor to from_tensor_to_numpy to better reflect its purpose of converting PyTorch tensors to numpy arrays or scalars.
- Adjusted all references to the renamed function throughout the codebase to maintain consistency.
- Enhanced the _NormalizationMixin class to reconstruct the stats dictionary from tensor stats using the new function, ensuring compatibility after loading state dicts.
- Added tests to verify the correct reconstruction of stats and functionality of methods dependent on self.stats after loading.

* refactor(pipeline): feature contract now categorizes between OBS or Action (#1867)

* refactor(processor): signature of transform_features

* refactor(processor): remove prefixes + processor respect new transform_features signature + update test accordingly

* refactor(processor): rename now is only for visual

* refactor(processor): update normalize processor

* refactor(processor): update vanilla processor features

* refactor(processor): feature contract now uses its own enum

* chore(processor): rename renameprocessor

* chore(processor): minor changes

* refactor(processor): add create & change aggregate

* refactor(processor): update aggregate

* refactor(processor): simplify to functions, fix features contracts and rename function

* test(processor): remove to converter tests as now they are very simple

* chore(docs): recover docs joint observations processor

* fix(processor): update RKP

* fix(tests): recv diff test_pipeline

* chore(tests): add docs to test

* chore(processor): leave obs language constant untouched

* fix(processor): correct new shape of feature in crop image processor

* refactor(eval): specify type parameters for preprocessor and postprocessor in eval_policy function (#1904)

* chore(processor): remove action prefixes (#1905)

* test(processor): all processors use now the same create_transition (#1906)

* test(processor): all processors use now the same create_transition

* test(processor): use identity instead of lambda for transition in pipelines

* fix(processor): specialized processors respect contract by raising if none (#1909)

* fix(processor): specialized processor now raise

* test(processor): fix tests for now raise specialized processors

* test(processor): use identity in newly introduced pipeline

* refactor(processor): clarify action types, distinguish PolicyAction, RobotAction, and EnvAction (#1908)

* refactor(processor): split action from policy, robots and environment

- Updated function names to robot_action_to_transition and robot_transition_to_action across multiple files to better reflect their purpose in processing robot actions.
- Adjusted references in the RobotProcessorPipeline and related components to ensure compatibility with the new naming convention.
- Enhanced type annotations for action parameters to improve code readability and maintainability.

* refactor(converters): rename robot_transition_to_action to transition_to_robot_action

- Updated function names across multiple files to improve clarity and consistency in processing robot actions.
- Adjusted references in RobotProcessorPipeline and related components to align with the new naming convention.
- Simplified action handling in the AddBatchDimensionProcessorStep by removing unnecessary checks for action presence.

* refactor(converters): update references to transition_to_robot_action

- Renamed all instances of robot_transition_to_action to transition_to_robot_action across multiple files for consistency and clarity in the processing of robot actions.
- Adjusted the RobotProcessorPipeline configurations to reflect the new naming convention, enhancing code readability.

* refactor(processor): update Torch2NumpyActionProcessorStep to extend ActionProcessorStep

- Changed the base class of Torch2NumpyActionProcessorStep from PolicyActionProcessorStep to ActionProcessorStep, aligning it with the current architecture of action processing.
- This modification enhances the clarity of the class's role in the processing pipeline.

* fix(processor): main action processor can take also EnvAction

---------

Co-authored-by: Steven Palma <steven.palma@huggingface.co>

* refactor(processor): phone processor is now an RobotActionProcessorStep

* fix(processor): use subprocessors in AddBatchDimensionProcessorStep only if we have the ingredients

* fix(robots): remove action prefix hard-coded in teleop keyboard and gamepad

* feat(processor): enhance type safety with generic DataProcessorPipeline for policy and robot pipelines (#1915)

* refactor(processor): enhance type annotations for processors in record, replay, teleoperate, and control utils

- Updated type annotations for preprocessor and postprocessor parameters in record_loop and predict_action functions to specify the expected dictionary types.
- Adjusted robot_action_processor type in ReplayConfig and TeleoperateConfig to improve clarity and maintainability.
- Ensured consistency in type definitions across multiple files, enhancing overall code readability.

* refactor(processor): enhance type annotations for RobotProcessorPipeline in various files

- Updated type annotations for RobotProcessorPipeline instances in evaluate.py, record.py, replay.py, teleoperate.py, and other related files to specify input and output types more clearly.
- Introduced new type conversions for PolicyAction and EnvTransition to improve type safety and maintainability across the processing pipelines.
- Ensured consistency in type definitions, enhancing overall code readability and reducing potential runtime errors.

* refactor(processor): update transition handling in processors to use transition_to_batch

- Replaced direct transition handling with transition_to_batch in various processor tests and implementations to ensure consistent batching of input data.
- Updated assertions in tests to reflect changes in data structure, enhancing clarity and maintainability.
- Improved overall code readability by standardizing the way transitions are processed across different processor types.

* refactor(tests): standardize transition key usage in processor tests

- Updated assertions in processor test files to utilize the TransitionKey for action references, enhancing consistency across tests.
- Replaced direct string references with TransitionKey constants for improved readability and maintainability.
- Ensured that all relevant tests reflect these changes, contributing to a more uniform approach in handling transitions.

* refactor(processor): unify action imports and enhance type clarity across multiple files

- Updated imports in various files to include RobotAction and PolicyAction directly from the processor module, improving clarity and consistency.
- Removed redundant imports from core, streamlining the codebase and enhancing maintainability.
- Adjusted type annotations and references in the RobotProcessorPipeline and related components to align with the new import structure, ensuring better type safety and readability.

* refactor(processor): migrate policy normalization to use factory functions

- Updated the migration script to utilize `make_pre_post_processors` and `make_policy_config` from `lerobot.policies.factory`, enhancing consistency with the current codebase.
- Improved normalization statistics extraction and processor pipeline creation, ensuring compatibility with the new `PolicyProcessorPipeline` architecture.
- Cleaned up configuration handling by removing unnecessary fields and adding normalization mapping directly to the config.
- Enhanced type safety and readability by refining feature type and normalization mode handling.

* debug(scripts): simplify record with processors (#1918)

Co-authored-by: Adil Zouitine <adilzouitinegm@gmail.com>

* refactor(processor): update migration script for policy normalization and hub integration

- Modified the migration script to include a branch argument for pushing to the hub, enhancing flexibility in version control.
- Improved error handling by ensuring the policy type is extracted from the configuration, promoting robustness.
- Streamlined the process of saving and pushing model components to the hub, allowing for a single commit with optional PR creation.
- Updated the commit message and description for better clarity on the migration changes and benefits, ensuring users are informed of the new architecture and usage.

* fixes for processors used in phone teleop

* fixes for rotation matrix

* add empty obs and act in create_initial_features

* use observation instead of obs

* docs(processor): update docstrings pipeline (#1920)

* chore(docs): Processor doc (#1685)

* chore(docs): initialize doc

* Added script for the second part of the processor doc

* precommit style nit

* improved part 2 of processor guide

* Add comprehensive documentation for processors in robotics

- Introduced a detailed guide on processors, covering their role in transforming raw robot data into model-ready inputs and vice versa.
- Explained core concepts such as EnvTransition, ProcessorStep, and RobotProcessor, along with their functionalities.
- Included examples of common processor steps like normalization, device management, batch processing, and text tokenization.
- Provided insights on building complete pipelines, integrating processors into training loops, and saving/loading configurations.
- Emphasized best practices and advanced features for effective usage of processors in robotics applications.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* feat(docs): Enhance introduction to processors with additional converter functions

- Updated the introduction to processors documentation to include default batch-to-transition and transition-to-batch converters.
- Added detailed descriptions and examples for new specialized converter functions: `to_transition_teleop_action`, `to_transition_robot_observation`, `to_output_robot_action`, and `to_dataset_frame`.
- Improved clarity on how these converters facilitate integration with existing robotics applications.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* Improved doc implement_your_own_pipeline
- Use normalization processor as default example
- Add section on transform features
- Add section on overrides.

* Add phone docs and use pipeline for robots/teleop docs

* Fix typo in documentation for adapters in robots/teleop section

* Enhance documentation for processors with detailed explanations and examples

- Updated the introduction to processors, clarifying the role of `EnvTransition` and `ProcessorStep`.
- Introduced `DataProcessorPipeline` as a generic orchestrator for chaining processor steps.
- Added comprehensive descriptions of new converter functions and their applications.
- Improved clarity on type safety and the differences between `RobotProcessorPipeline` and `PolicyProcessorPipeline`.
- Included examples for various processing scenarios, emphasizing best practices for data handling in robotics.

* Enhance documentation for processor migration and debugging

- Added detailed sections on the migration of models to the new `PolicyProcessorPipeline` system, including breaking changes and migration scripts.
- Introduced a comprehensive guide for debugging processor pipelines, covering common issues, step-by-step inspection, and runtime monitoring techniques.
- Updated examples to reflect new usage patterns and best practices for processor implementation and error handling.
- Clarified the role of various processor steps and their configurations in the context of robotics applications.

---------

Co-authored-by: Michel Aractingi <michel.aractingi@huggingface.co>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Pepijn <pepijn@huggingface.co>

* docs: Add new section for debugging processor pipelines

- Introduced a new documentation entry for debugging processor pipelines, enhancing the existing guide on processors.
- This addition aims to provide users with insights and best practices for troubleshooting and optimizing their processor workflows.

* fix(processor): phone examples (#1921)

* fix(processor): phone examples

* chore(processor): simplify gripper in phone example kinematic chain

---------

Co-authored-by: Steven Palma <steven.palma@huggingface.co>

* refactor(processors): several additions (#1926)

* chore(processor): remove merge_transitions functions (#1925)

* refactor(processors): move processors out of configs (#1927)

* chore(processor): streamline combine_features_dict (#1928)

* chore(policies): use new constants (#1929)

* fix(deps): right version transformers (#1930)

* fix(tests): add none + disable async tests for now (#1931)

* refactor(processor): transform_features loop + EAFP (#1932)

* fix(processors): make sure nested dict are also shallow copied (#1939)

* refactor(processor): replace ModelHubMixin with HubMixin and enhance save_pretrained method (#1937)

- Updated DataProcessorPipeline to use HubMixin instead of ModelHubMixin for improved functionality.
- Refactored save_pretrained method to handle saving

* refactor(docs): streamline monitoring hooks and enhance performance reporting

- Removed the log_shapes and measure_performance hooks, simplifying the monitoring process to focus on NaN checks.
- Updated performance reporting to include maximum processing times alongside average times for better insights.
- Clarified documentation regarding the processing pipeline and feature transformations.

* fix teleop, record and eval (#1940)

* fix cmd record, eval

* chore(processor): update input output of main 3 processors for better semantics (#1942)

* chore(processor): update input output of main 3 processors for better semantics

* refactor(processor): replace Any with RobotObservation for improved type safety in processors

* fix(processors): no PolicyObservation

* chore(processor): update with RobotObservation

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: AdilZouitine <adilzouitinegm@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

* test(processor): fix batch expectation

* feat(example): Add SO100 EE pipeline control (teleop+record) (#1943)

* feat(examples): add ee so100 processors teleop & record

* refactor(processor): improve FK processor for better use compatability

* docs(processor): enhance tutorial on implementing custom processors

- Updated the tutorial to use `NormalizerProcessorStep` as the primary example, clarifying its role in normalizing observations and actions.
- Improved explanations of the need for custom processors, emphasizing data compatibility and processing requirements.
- Added code snippets demonstrating the normalization process and the configuration of processor pipelines.
- Enhanced the introduction to processors, detailing their function as translators between raw robot data and model inputs.
- Included examples of real-world processor configurations for both training and inference scenarios.

* docs(debug): enhance debugging guide for processor pipelines

- Streamlined the introduction to clarify the challenges of debugging complex processor pipelines.
- Expanded the section on hooks, detailing their purpose and implementation for runtime monitoring.
- Introduced step-by-step debugging techniques, emphasizing the use of the `step_through()` method for inspecting intermediate states.
- Added examples of feature validation to ensure data structure contracts are met.
- Consolidated best practices for debugging, highlighting the synergy between hooks, step-through debugging, and feature validation.

* chore(processors): tokenizers raises and remove tensor conversion (#1949)

* chore(processor): remove unused transition_features dict

* feat(ee): add so100_to_so100_EE replay and evaluate examples

* chore(examples): homogenize style across example files (#1955)

* chore(examples): homogenize style across example files

* chore(examples): homogenize style across example files eval + replay

* chore(examples): homogenize headers

* test(async): fix feature manipulation (#1957)

* test(async): fix feature manipulation

* chore(processor): remove unused functions

* fix(processor): Preserve stats overrides in normalizer load_state_dict and fix training resumption (#1958)

* feat(processor): enhance normalization handling and state management

- Added support for additional normalization modes including IDENTITY.
- Introduced a new function `clean_state_dict` to remove specific substrings from state dict keys.
- Implemented preservation of explicitly provided normalization statistics during state loading.
- Updated training script to conditionally provide dataset statistics based on resume state.
- Expanded tests to verify the correct behavior of stats override preservation and loading.

* fix(train): remove redundant comment regarding state loading

- Removed a comment that noted the preprocessor and postprocessor state is already loaded when resuming training, as it was deemed unnecessary for clarity.

* test(processor): update tests to handle missing or invalid task keys

- Modified tests to assert that the processor raises appropriate exceptions when the task key is missing or has an invalid value in the complementary data.
- Ensured that the tests cover cases for None, integer, and mixed list task values, improving robustness against invalid inputs.

* fix(processor): enforce signatures

* chore(processor): update comments in record.py

* test(processor): fix isinstance and cuda test

* modify phone docs

* fix(processor): reorder output steps to ensure correct processing sequence (#1961)

- Moved DeviceProcessorStep to the end of the output steps in multiple processor files to maintain the intended processing order.
- Updated corresponding tests to reflect the change in step order.

* fix(processors): assumptions for robot_action_processor & teleop_action_processor (#1964)

* fix(processors): new assumptions pipeline

* fix(processors): ee jj phone teleop replay record working

* chore(processors): update comments and default vars

* chore(processor): remove unnecessary copy

* chore(processor): added todo assumption gripper

* fix(processors): eval using detected device

* finish phone docs

* fix correct image link

* feat(processor): implement migration detection and error handling for  processor configurations (#1968)

* feat(processor): implement migration detection and error handling for processor configurations

- Added ProcessorMigrationError to handle migration requirements for old model formats.
- Enhanced DataProcessorPipeline.from_pretrained to include robust migration detection logic.
- Implemented methods for resolving configuration sources, validating loaded configs, and checking for valid processor configurations.
- Introduced comprehensive tests for migration detection and configuration validation to ensure correct behavior.

* refactor(processor): simplify loading logic and enhance migration detection

- Refactored DataProcessorPipeline to implement a simplified three-way loading strategy for configuration files.
- Introduced explicit config_filename parameter to avoid ambiguity during loading.
- Updated ProcessorMigrationError to provide clearer error messages for migration requirements.
- Enhanced tests to cover new loading logic and ensure proper migration detection.
- Removed deprecated methods related to config source resolution.

* fix(processor) RL (#1953)

* fix(gym_manipulator) general fixes to make it compitable

* fix for dataset v3.0

* fix for gym_manipulator

* add map policy action to robot action wrappers in a seperate scripts

* added unittest for policy to robot bridge

* fixes for gripper penalty

* fix style

* fix gamepad controller

* fixes for sim teleop

* [pre-commit.ci] auto fixes from pre-commit.com hooks

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* modify numpy2torch to a regular processor as a quick fix

* missing imports?!

* - Removed the use of `AddRobotObservationAsComplimentaryData` from `gym_manipulator` and thus the codebase
- Added get_raw_joint_positions functions to RobotEnv
- Pass raw_joint_positions as input to the action_pipeline in `gym_manipulator`
- Add `InverseKinematicsRLStep` to be tailored towards the need of RL which requires the use of the IK solution as the main reference point of the control loop
- Added the option `use_ik_solution` in `EEReferenceDelta` step to rely on the ik solution rather than the joint values

* -Updated links to all the config files to place them in the new repo with configs compatible with the pipeline

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Steven Palma <imstevenpmwork@ieee.org>

* fix(tests): update test cases for loading pipelines with specific config filenames

- Modified test cases to include explicit configuration filenames when loading pipelines in `test_policy_robot_bridge.py`.
- Ensured that the tests reflect the correct loading behavior for both robot-to-policy and policy-to-robot transitions.

* fix(examples): train mps processor (#1970)

* fix(examples): train mps processor

* fix(processor): add MPS compatibility for float64 tensors

- Implemented a workaround to convert float64 tensors to float32 when using the MPS device, as MPS does not support float64.
- Added unit tests to verify the automatic conversion of float64 tensors to float32 and ensure compatibility with various tensor types on the MPS device.

---------

Co-authored-by: AdilZouitine <adilzouitinegm@gmail.com>

---------

Signed-off-by: Adil Zouitine <adilzouitinegm@gmail.com>
Signed-off-by: Pepijn <138571049+pkooij@users.noreply.github.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Simon Alibert <75076266+aliberts@users.noreply.github.com>
Co-authored-by: Pepijn <138571049+pkooij@users.noreply.github.com>
Co-authored-by: Steven Palma <imstevenpmwork@ieee.org>
Co-authored-by: Michel Aractingi <michel.aractingi@huggingface.co>
Co-authored-by: Steven Palma <steven.palma@huggingface.co>
Co-authored-by: Pepijn <pepijn@huggingface.co>

src/lerobot/datasets/utils.py

@@ -150,14 +150,20 @@ def get_video_size_in_mb(mp4_path: Path) -> float:
 
 
 def flatten_dict(d: dict, parent_key: str = "", sep: str = "/") -> dict:
-    """Flatten a nested dictionary structure by collapsing nested keys into one key with a separator.
+    """Flatten a nested dictionary by joining keys with a separator.
 
-    For example:
-    ```
-    >>> dct = {"a": {"b": 1, "c": {"d": 2}}, "e": 3}`
-    >>> print(flatten_dict(dct))
-    {"a/b": 1, "a/c/d": 2, "e": 3}
-    ```
+    Example:
+        >>> dct = {"a": {"b": 1, "c": {"d": 2}}, "e": 3}
+        >>> print(flatten_dict(dct))
+        {'a/b': 1, 'a/c/d': 2, 'e': 3}
+
+    Args:
+        d (dict): The dictionary to flatten.
+        parent_key (str): The base key to prepend to the keys in this level.
+        sep (str): The separator to use between keys.
+
+    Returns:
+        dict: A flattened dictionary.
     """
     items = []
     for k, v in d.items():
@@ -170,6 +176,20 @@ def flatten_dict(d: dict, parent_key: str = "", sep: str = "/") -> dict:
 
 
 def unflatten_dict(d: dict, sep: str = "/") -> dict:
+    """Unflatten a dictionary with delimited keys into a nested dictionary.
+
+    Example:
+        >>> flat_dct = {"a/b": 1, "a/c/d": 2, "e": 3}
+        >>> print(unflatten_dict(flat_dct))
+        {'a': {'b': 1, 'c': {'d': 2}}, 'e': 3}
+
+    Args:
+        d (dict): A dictionary with flattened keys.
+        sep (str): The separator used in the keys.
+
+    Returns:
+        dict: A nested dictionary.
+    """
     outdict = {}
     for key, value in d.items():
         parts = key.split(sep)
@@ -183,6 +203,19 @@ def unflatten_dict(d: dict, sep: str = "/") -> dict:
 
 
 def serialize_dict(stats: dict[str, torch.Tensor | np.ndarray | dict]) -> dict:
+    """Serialize a dictionary containing tensors or numpy arrays to be JSON-compatible.
+
+    Converts torch.Tensor, np.ndarray, and np.generic types to lists or native Python types.
+
+    Args:
+        stats (dict): A dictionary that may contain non-serializable numeric types.
+
+    Returns:
+        dict: A dictionary with all values converted to JSON-serializable types.
+
+    Raises:
+        NotImplementedError: If a value has an unsupported type.
+    """
     serialized_dict = {}
     for key, value in flatten_dict(stats).items():
         if isinstance(value, (torch.Tensor, np.ndarray)):
@@ -199,6 +232,17 @@ def serialize_dict(stats: dict[str, torch.Tensor | np.ndarray | dict]) -> dict:
 
 
 def embed_images(dataset: datasets.Dataset) -> datasets.Dataset:
+    """Embed image bytes into the dataset table before saving to Parquet.
+
+    This function prepares a Hugging Face dataset for serialization by converting
+    image objects into an embedded format that can be stored in Arrow/Parquet.
+
+    Args:
+        dataset (datasets.Dataset): The input dataset, possibly containing image features.
+
+    Returns:
+        datasets.Dataset: The dataset with images embedded in the table storage.
+    """
     # Embed image bytes into the table before saving to parquet
     format = dataset.format
     dataset = dataset.with_format("arrow")
@@ -208,11 +252,27 @@ def embed_images(dataset: datasets.Dataset) -> datasets.Dataset:
 
 
 def load_json(fpath: Path) -> Any:
+    """Load data from a JSON file.
+
+    Args:
+        fpath (Path): Path to the JSON file.
+
+    Returns:
+        Any: The data loaded from the JSON file.
+    """
     with open(fpath) as f:
         return json.load(f)
 
 
 def write_json(data: dict, fpath: Path) -> None:
+    """Write data to a JSON file.
+
+    Creates parent directories if they don't exist.
+
+    Args:
+        data (dict): The dictionary to write.
+        fpath (Path): The path to the output JSON file.
+    """
     fpath.parent.mkdir(exist_ok=True, parents=True)
     with open(fpath, "w") as f:
         json.dump(data, f, indent=4, ensure_ascii=False)
@@ -223,6 +283,16 @@ def write_info(info: dict, local_dir: Path) -> None:
 
 
 def load_info(local_dir: Path) -> dict:
+    """Load dataset info metadata from its standard file path.
+
+    Also converts shape lists to tuples for consistency.
+
+    Args:
+        local_dir (Path): The root directory of the dataset.
+
+    Returns:
+        dict: The dataset information dictionary.
+    """
     info = load_json(local_dir / INFO_PATH)
     for ft in info["features"].values():
         ft["shape"] = tuple(ft["shape"])
@@ -230,16 +300,40 @@ def load_info(local_dir: Path) -> dict:
 
 
 def write_stats(stats: dict, local_dir: Path) -> None:
+    """Serialize and write dataset statistics to their standard file path.
+
+    Args:
+        stats (dict): The statistics dictionary (can contain tensors/numpy arrays).
+        local_dir (Path): The root directory of the dataset.
+    """
     serialized_stats = serialize_dict(stats)
     write_json(serialized_stats, local_dir / STATS_PATH)
 
 
 def cast_stats_to_numpy(stats: dict) -> dict[str, dict[str, np.ndarray]]:
+    """Recursively cast numerical values in a stats dictionary to numpy arrays.
+
+    Args:
+        stats (dict): The statistics dictionary.
+
+    Returns:
+        dict: The statistics dictionary with values cast to numpy arrays.
+    """
     stats = {key: np.array(value) for key, value in flatten_dict(stats).items()}
     return unflatten_dict(stats)
 
 
 def load_stats(local_dir: Path) -> dict[str, dict[str, np.ndarray]] | None:
+    """Load dataset statistics and cast numerical values to numpy arrays.
+
+    Returns None if the stats file doesn't exist.
+
+    Args:
+        local_dir (Path): The root directory of the dataset.
+
+    Returns:
+        A dictionary of statistics or None if the file is not found.
+    """
     if not (local_dir / STATS_PATH).exists():
         return None
     stats = load_json(local_dir / STATS_PATH)
@@ -297,6 +391,18 @@ def backward_compatible_episodes_stats(
 def load_image_as_numpy(
     fpath: str | Path, dtype: np.dtype = np.float32, channel_first: bool = True
 ) -> np.ndarray:
+    """Load an image from a file into a numpy array.
+
+    Args:
+        fpath (str | Path): Path to the image file.
+        dtype (np.dtype): The desired data type of the output array. If floating,
+            pixels are scaled to [0, 1].
+        channel_first (bool): If True, converts the image to (C, H, W) format.
+            Otherwise, it remains in (H, W, C) format.
+
+    Returns:
+        np.ndarray: The image as a numpy array.
+    """
     img = PILImage.open(fpath).convert("RGB")
     img_array = np.array(img, dtype=dtype)
     if channel_first:  # (H, W, C) -> (C, H, W)
@@ -307,10 +413,19 @@ def load_image_as_numpy(
 
 
 def hf_transform_to_torch(items_dict: dict[str, list[Any]]) -> dict[str, list[torch.Tensor | str]]:
-    """Get a transform function that convert items from Hugging Face dataset (pyarrow)
-    to torch tensors. Importantly, images are converted from PIL, which corresponds to
-    a channel last representation (h w c) of uint8 type, to a torch image representation
-    with channel first (c h w) of float32 type in range [0,1].
+    """Convert a batch from a Hugging Face dataset to torch tensors.
+
+    This transform function converts items from Hugging Face dataset format (pyarrow)
+    to torch tensors. Importantly, images are converted from PIL objects (H, W, C, uint8)
+    to a torch image representation (C, H, W, float32) in the range [0, 1]. Other
+    types are converted to torch.tensor.
+
+    Args:
+        items_dict (dict): A dictionary representing a batch of data from a
+            Hugging Face dataset.
+
+    Returns:
+        dict: The batch with items converted to torch tensors.
     """
     for key in items_dict:
         first_item = items_dict[key][0]
@@ -325,6 +440,14 @@ def hf_transform_to_torch(items_dict: dict[str, list[Any]]) -> dict[str, list[to
 
 
 def is_valid_version(version: str) -> bool:
+    """Check if a string is a valid PEP 440 version.
+
+    Args:
+        version (str): The version string to check.
+
+    Returns:
+        bool: True if the version string is valid, False otherwise.
+    """
     try:
         packaging.version.parse(version)
         return True
@@ -338,6 +461,18 @@ def check_version_compatibility(
     current_version: str | packaging.version.Version,
     enforce_breaking_major: bool = True,
 ) -> None:
+    """Check for version compatibility between a dataset and the current codebase.
+
+    Args:
+        repo_id (str): The repository ID for logging purposes.
+        version_to_check (str | packaging.version.Version): The version of the dataset.
+        current_version (str | packaging.version.Version): The current version of the codebase.
+        enforce_breaking_major (bool): If True, raise an error on major version mismatch.
+
+    Raises:
+        BackwardCompatibilityError: If the dataset version is from a newer, incompatible
+            major version of the codebase.
+    """
     v_check = (
         packaging.version.parse(version_to_check)
         if not isinstance(version_to_check, packaging.version.Version)
@@ -355,7 +490,14 @@ def check_version_compatibility(
 
 
 def get_repo_versions(repo_id: str) -> list[packaging.version.Version]:
-    """Returns available valid versions (branches and tags) on given repo."""
+    """Return available valid versions (branches and tags) on a given Hub repo.
+
+    Args:
+        repo_id (str): The repository ID on the Hugging Face Hub.
+
+    Returns:
+        list[packaging.version.Version]: A list of valid versions found.
+    """
     api = HfApi()
     repo_refs = api.list_repo_refs(repo_id, repo_type="dataset")
     repo_refs = [b.name for b in repo_refs.branches + repo_refs.tags]
@@ -368,9 +510,22 @@ def get_repo_versions(repo_id: str) -> list[packaging.version.Version]:
 
 
 def get_safe_version(repo_id: str, version: str | packaging.version.Version) -> str:
-    """
-    Returns the version if available on repo or the latest compatible one.
-    Otherwise, will throw a `CompatibilityError`.
+    """Return the specified version if available on repo, or the latest compatible one.
+
+    If the exact version is not found, it looks for the latest version with the
+    same major version number that is less than or equal to the target minor version.
+
+    Args:
+        repo_id (str): The repository ID on the Hugging Face Hub.
+        version (str | packaging.version.Version): The target version.
+
+    Returns:
+        str: The safe version string (e.g., "v1.2.3") to use as a revision.
+
+    Raises:
+        RevisionNotFoundError: If the repo has no version tags.
+        BackwardCompatibilityError: If only older major versions are available.
+        ForwardCompatibilityError: If only newer major versions are available.
     """
     target_version = (
         packaging.version.parse(version) if not isinstance(version, packaging.version.Version) else version
@@ -412,6 +567,17 @@ def get_safe_version(repo_id: str, version: str | packaging.version.Version) ->
 
 
 def get_hf_features_from_features(features: dict) -> datasets.Features:
+    """Convert a LeRobot features dictionary to a `datasets.Features` object.
+
+    Args:
+        features (dict): A LeRobot-style feature dictionary.
+
+    Returns:
+        datasets.Features: The corresponding Hugging Face `datasets.Features` object.
+
+    Raises:
+        ValueError: If a feature has an unsupported shape.
+    """
     hf_features = {}
     for key, ft in features.items():
         if ft["dtype"] == "video":
@@ -439,6 +605,14 @@ def get_hf_features_from_features(features: dict) -> datasets.Features:
 
 
 def _validate_feature_names(features: dict[str, dict]) -> None:
+    """Validate that feature names do not contain invalid characters.
+
+    Args:
+        features (dict): The LeRobot features dictionary.
+
+    Raises:
+        ValueError: If any feature name contains '/'.
+    """
     invalid_features = {name: ft for name, ft in features.items() if "/" in name}
     if invalid_features:
         raise ValueError(f"Feature names should not contain '/'. Found '/' in '{invalid_features}'.")
@@ -447,8 +621,28 @@ def _validate_feature_names(features: dict[str, dict]) -> None:
 def hw_to_dataset_features(
     hw_features: dict[str, type | tuple], prefix: str, use_video: bool = True
 ) -> dict[str, dict]:
+    """Convert hardware-specific features to a LeRobot dataset feature dictionary.
+
+    This function takes a dictionary describing hardware outputs (like joint states
+    or camera image shapes) and formats it into the standard LeRobot feature
+    specification.
+
+    Args:
+        hw_features (dict): Dictionary mapping feature names to their type (float for
+            joints) or shape (tuple for images).
+        prefix (str): The prefix to add to the feature keys (e.g., "observation"
+            or "action").
+        use_video (bool): If True, image features are marked as "video", otherwise "image".
+
+    Returns:
+        dict: A LeRobot features dictionary.
+    """
     features = {}
-    joint_fts = {key: ftype for key, ftype in hw_features.items() if ftype is float}
+    joint_fts = {
+        key: ftype
+        for key, ftype in hw_features.items()
+        if ftype is float or (isinstance(ftype, PolicyFeature) and ftype.type != FeatureType.VISUAL)
+    }
     cam_fts = {key: shape for key, shape in hw_features.items() if isinstance(shape, tuple)}
 
     if joint_fts and prefix == "action":
@@ -479,6 +673,20 @@ def hw_to_dataset_features(
 def build_dataset_frame(
     ds_features: dict[str, dict], values: dict[str, Any], prefix: str
 ) -> dict[str, np.ndarray]:
+    """Construct a single data frame from raw values based on dataset features.
+
+    A "frame" is a dictionary containing all the data for a single timestep,
+    formatted as numpy arrays according to the feature specification.
+
+    Args:
+        ds_features (dict): The LeRobot dataset features dictionary.
+        values (dict): A dictionary of raw values from the hardware/environment.
+        prefix (str): The prefix to filter features by (e.g., "observation"
+            or "action").
+
+    Returns:
+        dict: A dictionary representing a single frame of data.
+    """
     frame = {}
     for key, ft in ds_features.items():
         if key in DEFAULT_FEATURES or not key.startswith(prefix):
@@ -492,6 +700,21 @@ def build_dataset_frame(
 
 
 def dataset_to_policy_features(features: dict[str, dict]) -> dict[str, PolicyFeature]:
+    """Convert dataset features to policy features.
+
+    This function transforms the dataset's feature specification into a format
+    that a policy can use, classifying features by type (e.g., visual, state,
+    action) and ensuring correct shapes (e.g., channel-first for images).
+
+    Args:
+        features (dict): The LeRobot dataset features dictionary.
+
+    Returns:
+        dict: A dictionary mapping feature keys to `PolicyFeature` objects.
+
+    Raises:
+        ValueError: If an image feature does not have a 3D shape.
+    """
     # TODO(aliberts): Implement "type" in dataset features and simplify this
     policy_features = {}
     for key, ft in features.items():
@@ -522,6 +745,58 @@ def dataset_to_policy_features(features: dict[str, dict]) -> dict[str, PolicyFea
     return policy_features
 
 
+def combine_feature_dicts(*dicts: dict) -> dict:
+    """Merge LeRobot grouped feature dicts.
+
+    - For 1D numeric specs (dtype not image/video/string) with "names": we merge the names and recompute the shape.
+    - For others (e.g. `observation.images.*`), the last one wins (if they are identical).
+
+    Args:
+        *dicts: A variable number of LeRobot feature dictionaries to merge.
+
+    Returns:
+        dict: A single merged feature dictionary.
+
+    Raises:
+        ValueError: If there's a dtype mismatch for a feature being merged.
+    """
+    out: dict = {}
+    for d in dicts:
+        for key, value in d.items():
+            if not isinstance(value, dict):
+                out[key] = value
+                continue
+
+            dtype = value.get("dtype")
+            shape = value.get("shape")
+            is_vector = (
+                dtype not in ("image", "video", "string")
+                and isinstance(shape, tuple)
+                and len(shape) == 1
+                and "names" in value
+            )
+
+            if is_vector:
+                # Initialize or retrieve the accumulating dict for this feature key
+                target = out.setdefault(key, {"dtype": dtype, "names": [], "shape": (0,)})
+                # Ensure consistent data types across merged entries
+                if "dtype" in target and dtype != target["dtype"]:
+                    raise ValueError(f"dtype mismatch for '{key}': {target['dtype']} vs {dtype}")
+
+                # Merge feature names: append only new ones to preserve order without duplicates
+                seen = set(target["names"])
+                for n in value["names"]:
+                    if n not in seen:
+                        target["names"].append(n)
+                        seen.add(n)
+                # Recompute the shape to reflect the updated number of features
+                target["shape"] = (len(target["names"]),)
+            else:
+                # For images/videos and non-1D entries: override with the latest definition
+                out[key] = value
+    return out
+
+
 def create_empty_dataset_info(
     codebase_version: str,
     fps: int,
@@ -532,6 +807,18 @@ def create_empty_dataset_info(
     data_files_size_in_mb: int | None = None,
     video_files_size_in_mb: int | None = None,
 ) -> dict:
+    """Create a template dictionary for a new dataset's `info.json`.
+
+    Args:
+        codebase_version (str): The version of the LeRobot codebase.
+        fps (int): The frames per second of the data.
+        features (dict): The LeRobot features dictionary for the dataset.
+        use_videos (bool): Whether the dataset will store videos.
+        robot_type (str | None): The type of robot used, if any.
+
+    Returns:
+        dict: A dictionary with the initial dataset metadata.
+    """
     return {
         "codebase_version": codebase_version,
         "robot_type": robot_type,
@@ -552,9 +839,23 @@ def create_empty_dataset_info(
 def check_delta_timestamps(
     delta_timestamps: dict[str, list[float]], fps: int, tolerance_s: float, raise_value_error: bool = True
 ) -> bool:
-    """This will check if all the values in delta_timestamps are multiples of 1/fps +/- tolerance.
-    This is to ensure that these delta_timestamps added to any timestamp from a dataset will themselves be
-    actual timestamps from the dataset.
+    """Check if delta timestamps are multiples of 1/fps +/- tolerance.
+
+    This ensures that adding these delta timestamps to any existing timestamp in
+    the dataset will result in a value that aligns with the dataset's frame rate.
+
+    Args:
+        delta_timestamps (dict): A dictionary where values are lists of time
+            deltas in seconds.
+        fps (int): The frames per second of the dataset.
+        tolerance_s (float): The allowed tolerance in seconds.
+        raise_value_error (bool): If True, raises an error on failure.
+
+    Returns:
+        bool: True if all deltas are valid, False otherwise.
+
+    Raises:
+        ValueError: If any delta is outside the tolerance and `raise_value_error` is True.
     """
     outside_tolerance = {}
     for key, delta_ts in delta_timestamps.items():
@@ -580,6 +881,15 @@ def check_delta_timestamps(
 
 
 def get_delta_indices(delta_timestamps: dict[str, list[float]], fps: int) -> dict[str, list[int]]:
+    """Convert delta timestamps in seconds to delta indices in frames.
+
+    Args:
+        delta_timestamps (dict): A dictionary of time deltas in seconds.
+        fps (int): The frames per second of the dataset.
+
+    Returns:
+        dict: A dictionary of frame delta indices.
+    """
     delta_indices = {}
     for key, delta_ts in delta_timestamps.items():
         delta_indices[key] = [round(d * fps) for d in delta_ts]
@@ -588,9 +898,17 @@ def get_delta_indices(delta_timestamps: dict[str, list[float]], fps: int) -> dic
 
 
 def cycle(iterable: Any) -> Iterator[Any]:
-    """The equivalent of itertools.cycle, but safe for Pytorch dataloaders.
+    """Create a dataloader-safe cyclical iterator.
 
-    See https://github.com/pytorch/pytorch/issues/23900 for information on why itertools.cycle is not safe.
+    This is an equivalent of `itertools.cycle` but is safe for use with
+    PyTorch DataLoaders with multiple workers.
+    See https://github.com/pytorch/pytorch/issues/23900 for details.
+
+    Args:
+        iterable: The iterable to cycle over.
+
+    Yields:
+        Items from the iterable, restarting from the beginning when exhausted.
     """
     iterator = iter(iterable)
     while True:
@@ -601,8 +919,14 @@ def cycle(iterable: Any) -> Iterator[Any]:
 
 
 def create_branch(repo_id: str, *, branch: str, repo_type: str | None = None) -> None:
-    """Create a branch on a existing Hugging Face repo. Delete the branch if it already
-    exists before creating it.
+    """Create a branch on an existing Hugging Face repo.
+
+    Deletes the branch if it already exists before creating it.
+
+    Args:
+        repo_id (str): The ID of the repository.
+        branch (str): The name of the branch to create.
+        repo_type (str | None): The type of the repository (e.g., "dataset").
     """
     api = HfApi()
 
@@ -620,9 +944,20 @@ def create_lerobot_dataset_card(
     dataset_info: dict | None = None,
     **kwargs,
 ) -> DatasetCard:
-    """
-    Keyword arguments will be used to replace values in src/lerobot/datasets/card_template.md.
-    Note: If specified, license must be one of https://huggingface.co/docs/hub/repositories-licenses.
+    """Create a `DatasetCard` for a LeRobot dataset.
+
+    Keyword arguments are used to replace values in the card template.
+    Note: If specified, `license` must be a valid license identifier from
+    https://huggingface.co/docs/hub/repositories-licenses.
+
+    Args:
+        tags (list | None): A list of tags to add to the dataset card.
+        dataset_info (dict | None): The dataset's info dictionary, which will
+            be displayed on the card.
+        **kwargs: Additional keyword arguments to populate the card template.
+
+    Returns:
+        DatasetCard: The generated dataset card object.
     """
     card_tags = ["LeRobot"]
 
@@ -675,6 +1010,15 @@ def validate_frame(frame: dict, features: dict) -> None:
 
 
 def validate_features_presence(actual_features: set[str], expected_features: set[str]) -> str:
+    """Check for missing or extra features in a frame.
+
+    Args:
+        actual_features (set[str]): The set of feature names present in the frame.
+        expected_features (set[str]): The set of feature names expected in the frame.
+
+    Returns:
+        str: An error message string if there's a mismatch, otherwise an empty string.
+    """
     error_message = ""
     missing_features = expected_features - actual_features
     extra_features = actual_features - expected_features
@@ -692,6 +1036,19 @@ def validate_features_presence(actual_features: set[str], expected_features: set
 def validate_feature_dtype_and_shape(
     name: str, feature: dict, value: np.ndarray | PILImage.Image | str
 ) -> str:
+    """Validate the dtype and shape of a single feature's value.
+
+    Args:
+        name (str): The name of the feature.
+        feature (dict): The feature specification from the LeRobot features dictionary.
+        value: The value of the feature to validate.
+
+    Returns:
+        str: An error message if validation fails, otherwise an empty string.
+
+    Raises:
+        NotImplementedError: If the feature dtype is not supported for validation.
+    """
     expected_dtype = feature["dtype"]
     expected_shape = feature["shape"]
     if is_valid_numpy_dtype_string(expected_dtype):
@@ -707,6 +1064,17 @@ def validate_feature_dtype_and_shape(
 def validate_feature_numpy_array(
     name: str, expected_dtype: str, expected_shape: list[int], value: np.ndarray
 ) -> str:
+    """Validate a feature that is expected to be a numpy array.
+
+    Args:
+        name (str): The name of the feature.
+        expected_dtype (str): The expected numpy dtype as a string.
+        expected_shape (list[int]): The expected shape.
+        value (np.ndarray): The numpy array to validate.
+
+    Returns:
+        str: An error message if validation fails, otherwise an empty string.
+    """
     error_message = ""
     if isinstance(value, np.ndarray):
         actual_dtype = value.dtype
@@ -726,6 +1094,18 @@ def validate_feature_numpy_array(
 def validate_feature_image_or_video(
     name: str, expected_shape: list[str], value: np.ndarray | PILImage.Image
 ) -> str:
+    """Validate a feature that is expected to be an image or video frame.
+
+    Accepts `np.ndarray` (channel-first or channel-last) or `PIL.Image.Image`.
+
+    Args:
+        name (str): The name of the feature.
+        expected_shape (list[str]): The expected shape (C, H, W).
+        value: The image data to validate.
+
+    Returns:
+        str: An error message if validation fails, otherwise an empty string.
+    """
     # Note: The check of pixels range ([0,1] for float and [0,255] for uint8) is done by the image writer threads.
     error_message = ""
     if isinstance(value, np.ndarray):
@@ -742,12 +1122,35 @@ def validate_feature_image_or_video(
 
 
 def validate_feature_string(name: str, value: str) -> str:
+    """Validate a feature that is expected to be a string.
+
+    Args:
+        name (str): The name of the feature.
+        value (str): The value to validate.
+
+    Returns:
+        str: An error message if validation fails, otherwise an empty string.
+    """
     if not isinstance(value, str):
         return f"The feature '{name}' is expected to be of type 'str', but type '{type(value)}' provided instead.\n"
     return ""
 
 
 def validate_episode_buffer(episode_buffer: dict, total_episodes: int, features: dict) -> None:
+    """Validate the episode buffer before it's written to disk.
+
+    Ensures the buffer has the required keys, contains at least one frame, and
+    has features consistent with the dataset's specification.
+
+    Args:
+        episode_buffer (dict): The buffer containing data for a single episode.
+        total_episodes (int): The current total number of episodes in the dataset.
+        features (dict): The LeRobot features dictionary for the dataset.
+
+    Raises:
+        ValueError: If the buffer is invalid.
+        NotImplementedError: If the episode index is manually set and doesn't match.
+    """
     if "size" not in episode_buffer:
         raise ValueError("size key not found in episode_buffer")