Files
lerobot-clone/src/lerobot/processor/migrate_policy_normalization.py
Adil Zouitine 0524551f52 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.
2025-08-07 11:04:15 +02:00

503 lines
19 KiB
Python

#!/usr/bin/env python
# Copyright 2024 The HuggingFace Inc. team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""
Generic script to migrate any policy model with normalization layers to the new pipeline-based system.
This script:
1. Loads an existing pretrained policy model
2. Extracts normalization statistics from the model
3. Creates both preprocessor and postprocessor:
- Preprocessor: normalizes both inputs (observations) and outputs (actions) for training
- Postprocessor: unnormalizes outputs (actions) for inference
4. Removes normalization layers from the model state_dict
5. Saves the new model and both processors
Usage:
python src/lerobot/processor/migrate_policy_normalization.py \
--pretrained-path lerobot/act_aloha_sim_transfer_cube_human \
--policy-type act \
--push-to-hub
"""
import argparse
import importlib
import json
import os
from copy import deepcopy
from pathlib import Path
from typing import Any
import torch
from huggingface_hub import hf_hub_download
from safetensors.torch import load_file as load_safetensors
from lerobot.configs.types import FeatureType, NormalizationMode, PolicyFeature
from lerobot.processor.batch_processor import ToBatchProcessor
from lerobot.processor.device_processor import DeviceProcessor
from lerobot.processor.normalize_processor import NormalizerProcessor, UnnormalizerProcessor
from lerobot.processor.pipeline import RobotProcessor
from lerobot.processor.rename_processor import RenameProcessor
# Policy type to class mapping
POLICY_CLASSES = {
"act": "lerobot.policies.act.modeling_act.ACTPolicy",
"diffusion": "lerobot.policies.diffusion.modeling_diffusion.DiffusionPolicy",
"pi0": "lerobot.policies.pi0.modeling_pi0.PI0Policy",
"pi0fast": "lerobot.policies.pi0fast.modeling_pi0fast.PI0FASTPolicy",
"smolvla": "lerobot.policies.smolvla.modeling_smolvla.SmolVLAPolicy",
"tdmpc": "lerobot.policies.tdmpc.modeling_tdmpc.TDMPCPolicy",
"vqbet": "lerobot.policies.vqbet.modeling_vqbet.VQBeTPolicy",
"sac": "lerobot.policies.sac.modeling_sac.SACPolicy",
"classifier": "lerobot.policies.classifier.modeling_classifier.ClassifierPolicy",
}
def extract_normalization_stats(state_dict: dict[str, torch.Tensor]) -> dict[str, dict[str, torch.Tensor]]:
"""Extract normalization statistics from model state_dict."""
stats = {}
# Define patterns to match and their prefixes to remove
normalization_patterns = [
"normalize_inputs.buffer_",
"unnormalize_outputs.buffer_",
"normalize_targets.buffer_",
"normalize.", # Must come after normalize_* patterns
"unnormalize.", # Must come after unnormalize_* patterns
"input_normalizer.",
"output_normalizer.",
]
# Process each key in state_dict
for key, tensor in state_dict.items():
# Try each pattern
for pattern in normalization_patterns:
if key.startswith(pattern):
# Extract the remaining part after the pattern
remaining = key[len(pattern) :]
parts = remaining.split(".")
# Need at least feature name and stat type
if len(parts) >= 2:
# Last part is the stat type (mean, std, min, max, etc.)
stat_type = parts[-1]
# Everything else is the feature name
feature_name = ".".join(parts[:-1]).replace("_", ".")
# Add to stats
if feature_name not in stats:
stats[feature_name] = {}
stats[feature_name][stat_type] = tensor.clone()
# Only process the first matching pattern
break
return stats
def detect_features_and_norm_modes(
config: dict[str, Any], stats: dict[str, dict[str, torch.Tensor]]
) -> tuple[dict[str, PolicyFeature], dict[FeatureType, NormalizationMode]]:
"""Detect features and normalization modes from config and stats."""
features = {}
norm_modes = {}
# First, check if there's a normalization_mapping in the config
if "normalization_mapping" in config:
print(f"Found normalization_mapping in config: {config['normalization_mapping']}")
# Extract normalization modes from config
for feature_name, mode_str in config["normalization_mapping"].items():
# Convert string to NormalizationMode enum
if mode_str == "mean_std":
mode = NormalizationMode.MEAN_STD
elif mode_str == "min_max":
mode = NormalizationMode.MIN_MAX
else:
print(f"Warning: Unknown normalization mode '{mode_str}' for feature '{feature_name}'")
continue
# Determine feature type from feature name
if "image" in feature_name or "visual" in feature_name:
feature_type = FeatureType.VISUAL
elif "state" in feature_name:
feature_type = FeatureType.STATE
elif "action" in feature_name:
feature_type = FeatureType.ACTION
else:
feature_type = FeatureType.STATE
norm_modes[feature_type] = mode
# Try to extract from config
if "features" in config:
for key, feature_config in config["features"].items():
shape = feature_config.get("shape", feature_config.get("dim"))
shape = (shape,) if isinstance(shape, int) else tuple(shape)
# Determine feature type
if "image" in key or "visual" in key:
feature_type = FeatureType.VISUAL
elif "state" in key:
feature_type = FeatureType.STATE
elif "action" in key:
feature_type = FeatureType.ACTION
else:
feature_type = FeatureType.STATE # Default
features[key] = PolicyFeature(feature_type, shape)
# If no features in config, infer from stats
if not features:
for key, stat_dict in stats.items():
# Get shape from any stat tensor
tensor = next(iter(stat_dict.values()))
shape = tuple(tensor.shape)
# Determine feature type based on key
if "image" in key or "visual" in key or "pixels" in key:
feature_type = FeatureType.VISUAL
elif "state" in key or "joint" in key or "position" in key:
feature_type = FeatureType.STATE
elif "action" in key:
feature_type = FeatureType.ACTION
else:
feature_type = FeatureType.STATE
features[key] = PolicyFeature(feature_type, shape)
# If normalization modes weren't in config, determine based on available stats
if not norm_modes:
for key, stat_dict in stats.items():
if key in features:
if "mean" in stat_dict and "std" in stat_dict:
feature_type = features[key].type
if feature_type not in norm_modes:
norm_modes[feature_type] = NormalizationMode.MEAN_STD
elif "min" in stat_dict and "max" in stat_dict:
feature_type = features[key].type
if feature_type not in norm_modes:
norm_modes[feature_type] = NormalizationMode.MIN_MAX
# Default normalization modes if not detected
if FeatureType.VISUAL not in norm_modes:
norm_modes[FeatureType.VISUAL] = NormalizationMode.MEAN_STD
if FeatureType.STATE not in norm_modes:
norm_modes[FeatureType.STATE] = NormalizationMode.MIN_MAX
if FeatureType.ACTION not in norm_modes:
norm_modes[FeatureType.ACTION] = NormalizationMode.MEAN_STD
return features, norm_modes
def remove_normalization_layers(state_dict: dict[str, torch.Tensor]) -> dict[str, torch.Tensor]:
"""Remove normalization layers from state_dict."""
new_state_dict = {}
# Patterns to remove
remove_patterns = [
"normalize_inputs.",
"unnormalize_outputs.",
"normalize_targets.", # Added pattern for target normalization
"normalize.",
"unnormalize.",
"input_normalizer.",
"output_normalizer.",
"normalizer.",
]
for key, tensor in state_dict.items():
should_remove = any(pattern in key for pattern in remove_patterns)
if not should_remove:
new_state_dict[key] = tensor
return new_state_dict
def convert_features_to_policy_features(features_dict: dict[str, dict]) -> dict[str, PolicyFeature]:
"""Convert features from old format to PolicyFeature objects."""
converted_features = {}
for key, feature_dict in features_dict.items():
# Determine feature type based on key
if "image" in key or "visual" in key:
feature_type = FeatureType.VISUAL
elif "state" in key:
feature_type = FeatureType.STATE
elif "action" in key:
feature_type = FeatureType.ACTION
else:
feature_type = FeatureType.STATE
# Get shape from feature dict
shape = feature_dict.get("shape", feature_dict.get("dim"))
shape = (shape,) if isinstance(shape, int) else tuple(shape)
converted_features[key] = PolicyFeature(feature_type, shape)
return converted_features
def load_model_from_hub(
repo_id: str, revision: str = None
) -> tuple[dict[str, torch.Tensor], dict[str, Any], dict[str, Any]]:
"""Load model state_dict and config from hub."""
# Download files
safetensors_path = hf_hub_download(repo_id=repo_id, filename="model.safetensors", revision=revision)
config_path = hf_hub_download(repo_id=repo_id, filename="config.json", revision=revision)
train_config_path = hf_hub_download(repo_id=repo_id, filename="train_config.json", revision=revision)
# Load state_dict
state_dict = load_safetensors(safetensors_path)
# Load config
with open(config_path) as f:
config = json.load(f)
with open(train_config_path) as f:
train_config = json.load(f)
return state_dict, config, train_config
def main():
parser = argparse.ArgumentParser(
description="Migrate policy models with normalization layers to new pipeline system"
)
parser.add_argument(
"--pretrained-path",
type=str,
required=True,
help="Path to pretrained model (hub repo or local directory)",
)
parser.add_argument(
"--output-dir",
type=str,
default=None,
help="Output directory for migrated model (default: same as pretrained-path)",
)
parser.add_argument("--push-to-hub", action="store_true", help="Push migrated model to hub")
parser.add_argument(
"--hub-repo-id",
type=str,
default=None,
help="Hub repository ID for pushing (default: same as pretrained-path)",
)
parser.add_argument("--revision", type=str, default=None, help="Revision of the model to load")
parser.add_argument("--private", action="store_true", help="Make the hub repository private")
args = parser.parse_args()
# Load model and config
print(f"Loading model from {args.pretrained_path}...")
if os.path.isdir(args.pretrained_path):
# Local directory
state_dict = load_safetensors(os.path.join(args.pretrained_path, "model.safetensors"))
with open(os.path.join(args.pretrained_path, "config.json")) as f:
config = json.load(f)
with open(os.path.join(args.pretrained_path, "train_config.json")) as f:
train_config = json.load(f)
else:
# Hub repository
state_dict, config, train_config = load_model_from_hub(args.pretrained_path, args.revision)
# Extract normalization statistics
print("Extracting normalization statistics...")
stats = extract_normalization_stats(state_dict)
print(f"Found normalization statistics for: {list(stats.keys())}")
# Detect input features and normalization modes
print("Detecting features and normalization modes...")
features, norm_map = detect_features_and_norm_modes(config, stats)
print(f"Detected features: {list(features.keys())}")
print(f"Normalization modes: {norm_map}")
# Remove normalization layers from state_dict
print("Removing normalization layers from model...")
new_state_dict = remove_normalization_layers(state_dict)
removed_keys = set(state_dict.keys()) - set(new_state_dict.keys())
if removed_keys:
print(f"Removed {len(removed_keys)} normalization layer keys")
# Determine output path
if args.output_dir:
output_dir = Path(args.output_dir)
else:
if os.path.isdir(args.pretrained_path):
output_dir = Path(args.pretrained_path).parent / f"{Path(args.pretrained_path).name}_migrated"
else:
output_dir = Path(f"./{args.pretrained_path.replace('/', '_')}_migrated")
output_dir.mkdir(parents=True, exist_ok=True)
# Clean up config - remove normalization_mapping field
cleaned_config = dict(config)
if "normalization_mapping" in cleaned_config:
print("Removing 'normalization_mapping' field from config")
del cleaned_config["normalization_mapping"]
policy_type = deepcopy(cleaned_config["type"])
del cleaned_config["type"]
# Instantiate the policy model with cleaned config and load the cleaned state dict
print(f"Instantiating {policy_type} policy model...")
policy_class_path = POLICY_CLASSES[policy_type]
module_path, class_name = policy_class_path.rsplit(".", 1)
module = importlib.import_module(module_path)
policy_class = getattr(module, class_name)
# Create config class instance
config_module_path = module_path.replace("modeling", "configuration")
config_module = importlib.import_module(config_module_path)
# Handle special cases for config class names
config_class_names = {
"act": "ACTConfig",
"diffusion": "DiffusionConfig",
"pi0": "PI0Config",
"pi0fast": "PI0FASTConfig",
"smolvla": "SmolVLAConfig",
"tdmpc": "TDMPCConfig",
"vqbet": "VQBeTConfig",
"sac": "SACConfig",
"classifier": "ClassifierConfig",
}
config_class_name = config_class_names.get(policy_type, f"{policy_type.upper()}Config")
config_class = getattr(config_module, config_class_name)
# Convert input_features and output_features to PolicyFeature objects - these are mandatory
if "input_features" not in cleaned_config:
raise ValueError("Missing mandatory 'input_features' in config")
if "output_features" not in cleaned_config:
raise ValueError("Missing mandatory 'output_features' in config")
cleaned_config["input_features"] = convert_features_to_policy_features(cleaned_config["input_features"])
cleaned_config["output_features"] = convert_features_to_policy_features(cleaned_config["output_features"])
# Create config instance from cleaned config dict
policy_config = config_class(**cleaned_config)
# Create policy instance - some policies expect dataset_stats
policy = policy_class(policy_config)
# Load the cleaned state dict
policy.load_state_dict(new_state_dict, strict=True)
print("Successfully loaded cleaned state dict into policy model")
# Now create preprocessor and postprocessor with cleaned_config available
print("Creating preprocessor and postprocessor...")
# The pattern from existing processor factories:
# - Preprocessor has two NormalizerProcessors: one for input_features, one for output_features
# - Postprocessor has one UnnormalizerProcessor for output_features only
# Get features from cleaned_config (now they're PolicyFeature objects)
input_features = cleaned_config.get("input_features", {})
output_features = cleaned_config.get("output_features", {})
# Create preprocessor with two normalizers (following the pattern from processor factories)
preprocessor_steps = [
RenameProcessor(rename_map={}),
NormalizerProcessor(
features={**input_features, **output_features},
norm_map=norm_map,
stats=stats,
),
ToBatchProcessor(),
DeviceProcessor(device=policy_config.device),
]
preprocessor = RobotProcessor(steps=preprocessor_steps, name="robot_preprocessor")
# Create postprocessor with unnormalizer for outputs only
postprocessor_steps = [
DeviceProcessor(device="cpu"),
UnnormalizerProcessor(features=output_features, norm_map=norm_map, stats=stats),
]
postprocessor = RobotProcessor(steps=postprocessor_steps, name="robot_postprocessor")
# Determine hub repo ID if pushing to hub
if args.push_to_hub:
if args.hub_repo_id:
hub_repo_id = args.hub_repo_id
else:
if not os.path.isdir(args.pretrained_path):
# Use same repo with "_migrated" suffix
hub_repo_id = f"{args.pretrained_path}_migrated"
else:
raise ValueError("--hub-repo-id must be specified when pushing local model to hub")
else:
hub_repo_id = None
# Save preprocessor and postprocessor to root directory
print(f"Saving preprocessor to {output_dir}...")
preprocessor.save_pretrained(output_dir)
if args.push_to_hub:
preprocessor.push_to_hub(repo_id=hub_repo_id, private=args.private)
print(f"Saving postprocessor to {output_dir}...")
postprocessor.save_pretrained(output_dir)
if args.push_to_hub:
postprocessor.push_to_hub(repo_id=hub_repo_id, private=args.private)
# Save model using the policy's save_pretrained method
print(f"Saving model to {output_dir}...")
policy.save_pretrained(
output_dir, push_to_hub=args.push_to_hub, repo_id=hub_repo_id, private=args.private
)
# Generate and save model card
print("Generating model card...")
# Get metadata from original config
dataset_repo_id = train_config.get("repo_id", "unknown")
license = config.get("license", "apache-2.0")
tags = config.get("tags", ["robotics", "lerobot", policy_type]) or ["robotics", "lerobot", policy_type]
tags = set(tags).union({"robotics", "lerobot", policy_type})
tags = list(tags)
# Generate model card
card = policy.generate_model_card(
dataset_repo_id=dataset_repo_id, model_type=policy_type, license=license, tags=tags
)
# Save model card locally
card.save(str(output_dir / "README.md"))
print(f"Model card saved to {output_dir / 'README.md'}")
# Push model card to hub if requested
if args.push_to_hub:
from huggingface_hub import HfApi
api = HfApi()
api.upload_file(
path_or_fileobj=str(output_dir / "README.md"),
path_in_repo="README.md",
repo_id=hub_repo_id,
repo_type="model",
commit_message="Add model card for migrated model",
)
print("Model card pushed to hub")
print("\nMigration complete!")
print(f"Migrated model saved to: {output_dir}")
if args.push_to_hub:
print(f"Successfully pushed to https://huggingface.co/{hub_repo_id}")
if __name__ == "__main__":
main()