From 5d0a20bd9c0d99d885421f50b4fccd2c9fc99def Mon Sep 17 00:00:00 2001
From: CarolinePascal <caroline8.pascal@gmail.com>
Date: Sun, 26 Apr 2026 13:55:36 +0200
Subject: [PATCH] feat(video): alias "av1" to "libsvtav1" for backward compat

---
 src/lerobot/datasets/video_utils.py   |  6 ++++++
 tests/datasets/test_video_encoding.py | 12 ++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/src/lerobot/datasets/video_utils.py b/src/lerobot/datasets/video_utils.py
index 0e930b5f3..209490db7 100644
--- a/src/lerobot/datasets/video_utils.py
+++ b/src/lerobot/datasets/video_utils.py
@@ -138,6 +138,12 @@ class VideoEncoderConfig:
         also silently rewritten to ``libsvtav1`` so encoding never hard-fails on
         a host missing the requested encoder.
         """
+        # Backward compatibility: older datasets persist ``vcodec="av1"`` in
+        # ``info.json``. Rewrite to the canonical encoder name *before* the
+        # validation check below so loading those datasets keeps working.
+        if self.vcodec == "av1":
+            self.vcodec = "libsvtav1"
+
         if self.vcodec not in VALID_VIDEO_CODECS:
             raise ValueError(f"Invalid vcodec '{self.vcodec}'. Must be one of: {sorted(VALID_VIDEO_CODECS)}")
         if self.vcodec == "auto":
diff --git a/tests/datasets/test_video_encoding.py b/tests/datasets/test_video_encoding.py
index 6dde3a36b..6c49625d3 100644
--- a/tests/datasets/test_video_encoding.py
+++ b/tests/datasets/test_video_encoding.py
@@ -311,6 +311,18 @@ class TestEncoderDetection:
         assert "h264_videotoolbox" in VALID_VIDEO_CODECS
         assert "h264_nvenc" in VALID_VIDEO_CODECS
 
+    def test_av1_alias_resolves_to_libsvtav1(self):
+        """Older datasets persist ``vcodec="av1"``; backward-compat alias must keep them loadable."""
+        cfg = VideoEncoderConfig(vcodec="av1")
+        assert cfg.vcodec == "libsvtav1"
+
+    def test_av1_alias_persisted_after_resolve(self):
+        """Repeated calls to ``resolve_vcodec`` should be idempotent (alias only fires once)."""
+        cfg = VideoEncoderConfig(vcodec="av1")
+        assert cfg.vcodec == "libsvtav1"
+        cfg.resolve_vcodec()
+        assert cfg.vcodec == "libsvtav1"
+
 
 ARTIFACTS = Path(__file__).parent.parent / "fixtures" / "artifacts" / "videos"