feat(encoding parameters): adding support for user provided video encoding parameters (#3455)

* chore(video backend): renaming codec into video_backend in get_safe_default_video_backend()

* feat(pyav utils): adding suport for PyAV encoding parameters validation

* feat(VideoEncoderConfig): creating a VideoEncoderConfig to encapsulate encoding parameters

* feat(VideoEncoderConfig): propagating the VideoEncoderConfig in the codebase

* chore(docs): updating the docs

* feat(metadata): adding encoding parameters in dataset metadata

* fix(concatenation compatibility): adding compatibility check when concatenating video files

* feat(VideoEncoderConfig init): making VideoEncoderConfig more robust and adaptable to multiple backends

* feat(pyav checks): making pyav parameters checks more robust

* chore(duplicate): removing duplicate get_codec_options definition

* test(existing): adapting existing tests

* test(new): adding new tests for encoding related features

* chore(format): fixing formatting issues

* chore(PyAV): cleaning up PyAV utils and encoding parameters checks to stick to the minimun required tooling.

* chore(format): formatting code

* chore(doctrings): updating docstrings

* fix(camera_encoder_config): Removing camera_encoder_config from LeRobotDataset, as it's only required in LeRobotDatasetWriter.

* feat(default values): applying a consistent naming convention for default RGB cameras video encoder parameters

* fix(rollout): propagating VideoEncoderConfig to the latest recording modes

* chore(format): formatting code, fixing error messages and variable names

* fix(arguments order): reverting changes in arguments order in StreamingVideoEncoder

* chore(relative imports): switching to relative local imports within lerobot.datasets

* test(artifacts): cleaning up artifacts for the video encoding tests

* chore(docs): updating docs

* chore(fromat): formatting code

* fix(imports): refactoring the file architecture to avoid circular imports. VideoEncoderConfig is now defined in lerobot.configs and lazily imports av at runtime.

* fix(typos): fixing typos and small mistakes

* test(factories): updating factories

* feat(aggregate): updating dataset aggregation procedure. Encoding tuning paramters (crf, g,...) are ignored for validation and changed to None in the aggregated dataset if incompatible.

* docs(typos): fixing typos

* fix(deletion): reverting unwanted deletion

* fix(typos): fixing multiple typos

* feat(codec options): passing codec options to lerobot_edit_dataset episode deletion tool

* typo(typo): typo

* fix(typos): fixing remaining typos

* chore(rename): renaming camera_encoder_config to camera_encoder

* docs(clean): cleaning and formating docs

* docs(dataset): addind details about datasets

* chore(format): formatting code

* docs(warning): adding warning regarding encoding parameters modification

* fix(re-encoding): removing inconsistent re-encoding option in lerobot_edit_dataset

* typos(typos): typos

* chore(format): resolving prettier issues

* fix(h264_nvenc): fixing crf handling for h264_nvenc

* docs(clean): removing too technical parts of the docs

* fix(imports): fixing imports at the __init__ level

* fix(imports): fixing not very pretty imports in video config file
This commit is contained in:
Caroline Pascal
2026-05-14 23:46:42 +02:00
committed by GitHub
parent 0a4a7c40ad
commit bd9619dfc3
56 changed files with 1765 additions and 527 deletions
+2
View File
@@ -41,6 +41,8 @@
title: Using the Dataset Tools
- local: dataset_subtask
title: Using Subtasks in the Dataset
- local: video_encoding_parameters
title: Video encoding parameters
- local: streaming_video_encoding
title: Streaming Video Encoding
title: "Datasets"
+1 -1
View File
@@ -90,6 +90,6 @@ lerobot-record \
--dataset.single_task="Your task description" \
--dataset.streaming_encoding=true \
--dataset.encoder_threads=2 \
# --dataset.vcodec=auto \
# --dataset.camera_encoder.vcodec=auto \
--policy.path=${HF_USER}/act_policy
```
+1 -1
View File
@@ -194,7 +194,7 @@ lerobot-record \
--dataset.single_task="Navigate around obstacles" \
--dataset.streaming_encoding=true \
--dataset.encoder_threads=2 \
# --dataset.vcodec=auto \
# --dataset.camera_encoder.vcodec=auto \
--display_data=true
```
+1 -1
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@@ -123,7 +123,7 @@ lerobot-record \
--dataset.single_task="Grab and handover the red cube to the other arm" \
--dataset.streaming_encoding=true \
--dataset.encoder_threads=2 \
# --dataset.vcodec=auto \
# --dataset.camera_encoder.vcodec=auto \
--policy.path=<user>/groot-bimanual \ # your trained model
--dataset.episode_time_s=30 \
--dataset.reset_time_s=10
+2 -2
View File
@@ -232,7 +232,7 @@ lerobot-record \
--dataset.private=true \
--dataset.streaming_encoding=true \
--dataset.encoder_threads=2 \
# --dataset.vcodec=auto \
# --dataset.camera_encoder.vcodec=auto \
--display_data=true
```
@@ -278,6 +278,6 @@ lerobot-record \
--dataset.num_episodes=10 \
--dataset.streaming_encoding=true \
--dataset.encoder_threads=2 \
# --dataset.vcodec=auto \
# --dataset.camera_encoder.vcodec=auto \
--policy.path=outputs/train/hopejr_hand/checkpoints/last/pretrained_model
```
+1 -1
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@@ -193,7 +193,7 @@ lerobot-record \
--dataset.num_episodes=5 \
--dataset.single_task="Grab the black cube" \
--dataset.streaming_encoding=true \
# --dataset.vcodec=auto \
# --dataset.camera_encoder.vcodec=auto \
--dataset.encoder_threads=2
```
</hfoption>
+1 -1
View File
@@ -43,7 +43,7 @@ lerobot-record \
--dataset.num_episodes=5 \
--dataset.single_task="Grab the black cube" \
--dataset.streaming_encoding=true \
# --dataset.vcodec=auto \
# --dataset.camera_encoder.vcodec=auto \
--dataset.encoder_threads=2
```
+2 -2
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@@ -161,7 +161,7 @@ lerobot-record \
--dataset.private=true \
--dataset.streaming_encoding=true \
--dataset.encoder_threads=2 \
# --dataset.vcodec=auto \
# --dataset.camera_encoder.vcodec=auto \
--display_data=true
```
@@ -203,7 +203,7 @@ lerobot-record \
--dataset.private=true \
--dataset.streaming_encoding=true \
--dataset.encoder_threads=2 \
# --dataset.vcodec=auto \
# --dataset.camera_encoder.vcodec=auto \
--display_data=true
```
+1 -1
View File
@@ -108,7 +108,7 @@ lerobot-record \
--dataset.num_episodes=10 \
--dataset.streaming_encoding=true \
--dataset.encoder_threads=2 \
# --dataset.vcodec=auto \
# --dataset.camera_encoder.vcodec=auto \
# <- Teleop optional if you want to teleoperate in between episodes \
# --teleop.type=so100_leader \
# --teleop.port=/dev/ttyACM0 \
+22 -22
View File
@@ -17,9 +17,9 @@ This makes `save_episode()` near-instant (the video is already encoded by the ti
| Parameter | CLI Flag | Type | Default | Description |
| ----------------------- | --------------------------------- | ------------- | ------------- | ----------------------------------------------------------------- |
| `streaming_encoding` | `--dataset.streaming_encoding` | `bool` | `True` | Enable real-time encoding during capture |
| `vcodec` | `--dataset.vcodec` | `str` | `"libsvtav1"` | Video codec. `"auto"` detects best HW encoder |
| `vcodec` | `--dataset.camera_encoder.vcodec` | `str` | `"libsvtav1"` | Video codec. `"auto"` detects best HW encoder |
| `encoder_threads` | `--dataset.encoder_threads` | `int \| None` | `None` (auto) | Threads per encoder instance. `None` will leave the vcoded decide |
| `encoder_queue_maxsize` | `--dataset.encoder_queue_maxsize` | `int` | `60` | Max buffered frames per camera (~2s at 30fps). Consumes RAM |
| `encoder_queue_maxsize` | `--dataset.encoder_queue_maxsize` | `int` | `30` | Max buffered frames per camera (~1s at 30fps). Consumes RAM |
## 3. Performance Considerations
@@ -48,7 +48,7 @@ This parameter controls how many threads each encoder instance uses internally:
### Backpressure and Frame Dropping
Each camera has a bounded queue (`encoder_queue_maxsize`, default 60 frames). When the encoder can't keep up:
Each camera has a bounded queue (`encoder_queue_maxsize`, default 30 frames). When the encoder can't keep up:
1. The queue fills up (consuming RAM)
2. New frames are **dropped** (not blocked) — the capture loop continues uninterrupted
@@ -82,15 +82,15 @@ Use HW encoding when:
### Available HW Encoders
| Encoder | Platform | Hardware | CLI Value |
| ------------------- | ------------- | ------------------------------------------------------------------------------------------------ | ------------------------------------ |
| `h264_videotoolbox` | macOS | Apple Silicon / Intel | `--dataset.vcodec=h264_videotoolbox` |
| `hevc_videotoolbox` | macOS | Apple Silicon / Intel | `--dataset.vcodec=hevc_videotoolbox` |
| `h264_nvenc` | Linux/Windows | NVIDIA GPU | `--dataset.vcodec=h264_nvenc` |
| `hevc_nvenc` | Linux/Windows | NVIDIA GPU | `--dataset.vcodec=hevc_nvenc` |
| `h264_vaapi` | Linux | Intel/AMD GPU | `--dataset.vcodec=h264_vaapi` |
| `h264_qsv` | Linux/Windows | Intel Quick Sync | `--dataset.vcodec=h264_qsv` |
| `auto` | Any | Probes the system for available HW encoders. Falls back to `libsvtav1` if no HW encoder is found | `--dataset.vcodec=auto` |
| Encoder | Platform | Hardware | CLI Value |
| ------------------- | ------------- | ------------------------------------------------------------------------------------------------ | --------------------------------------------------- |
| `h264_videotoolbox` | macOS | Apple Silicon / Intel | `--dataset.camera_encoder.vcodec=h264_videotoolbox` |
| `hevc_videotoolbox` | macOS | Apple Silicon / Intel | `--dataset.camera_encoder.vcodec=hevc_videotoolbox` |
| `h264_nvenc` | Linux/Windows | NVIDIA GPU | `--dataset.camera_encoder.vcodec=h264_nvenc` |
| `hevc_nvenc` | Linux/Windows | NVIDIA GPU | `--dataset.camera_encoder.vcodec=hevc_nvenc` |
| `h264_vaapi` | Linux | Intel/AMD GPU | `--dataset.camera_encoder.vcodec=h264_vaapi` |
| `h264_qsv` | Linux/Windows | Intel Quick Sync | `--dataset.camera_encoder.vcodec=h264_qsv` |
| `auto` | Any | Probes the system for available HW encoders. Falls back to `libsvtav1` if no HW encoder is found | `--dataset.camera_encoder.vcodec=auto` |
> [!NOTE]
> In order to use the HW accelerated encoders you might need to upgrade your GPU drivers.
@@ -100,15 +100,15 @@ Use HW encoding when:
## 5. Troubleshooting
| Symptom | Likely Cause | Fix |
| ------------------------------------------------------------------ | -------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| System freezes or choppy robot movement or Rerun visualization lag | CPU starved (100% load usage) | Close other apps, reduce encoding throughput, lower `encoder_threads`, use `h264`, use `display_data=False`. If the CPU continues to be at 100% then it might be insufficient for your setup, consider `--dataset.streaming_encoding=false` or HW encoding (`--dataset.vcodec=auto`) |
| "Encoder queue full" warnings or dropped frames in dataset | Encoder can't keep up (Queue overflow) | If CPU is not at 100%: Increase `encoder_threads`, increase `encoder_queue_maxsize` or use HW encoding (`--dataset.vcodec=auto`). |
| High RAM usage | Queue filling faster than encoding | `encoder_threads` too low or CPU insufficient. Reduce `encoder_queue_maxsize` or use HW encoding |
| Large video files | Using HW encoder or H.264 | Expected trade-off. Switch to `libsvtav1` if CPU allows |
| `save_episode()` still slow | `streaming_encoding` is `False` | Set `--dataset.streaming_encoding=true` |
| Encoder thread crash | Codec not available or invalid settings | Check `vcodec` is installed, try `--dataset.vcodec=auto` |
| Recorded dataset is missing frames | CPU/GPU starvation or occasional load spikes | If ~5% of frames are missing, your system is likely overloaded — follow the recommendations above. If fewer frames are missing (~2%), they are probably due to occasional transient load spikes (often at startup) and can be considered expected. |
| Symptom | Likely Cause | Fix |
| ------------------------------------------------------------------ | -------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| System freezes or choppy robot movement or Rerun visualization lag | CPU starved (100% load usage) | Close other apps, reduce encoding throughput, lower `encoder_threads`, use `h264`, use `display_data=False`. If the CPU continues to be at 100% then it might be insufficient for your setup, consider `--dataset.streaming_encoding=false` or HW encoding (`--dataset.camera_encoder.vcodec=auto`) |
| "Encoder queue full" warnings or dropped frames in dataset | Encoder can't keep up (Queue overflow) | If CPU is not at 100%: Increase `encoder_threads`, increase `encoder_queue_maxsize` or use HW encoding (`--dataset.camera_encoder.vcodec=auto`). |
| High RAM usage | Queue filling faster than encoding | `encoder_threads` too low or CPU insufficient. Reduce `encoder_queue_maxsize` or use HW encoding |
| Large video files | Using HW encoder or H.264 | Expected trade-off. Switch to `libsvtav1` if CPU allows |
| `save_episode()` still slow | `streaming_encoding` is `False` | Set `--dataset.streaming_encoding=true` |
| Encoder thread crash | Codec not available or invalid settings | Check `vcodec` is installed, try `--dataset.camera_encoder.vcodec=auto` |
| Recorded dataset is missing frames | CPU/GPU starvation or occasional load spikes | If ~5% of frames are missing, your system is likely overloaded — follow the recommendations above. If fewer frames are missing (~2%), they are probably due to occasional transient load spikes (often at startup) and can be considered expected. |
## 6. Recommended Configurations
@@ -146,7 +146,7 @@ On very constrained systems, streaming encoding may compete too heavily with the
# 2camsx 640x480x3 @30fps: Requires some tuning.
# Use H.264, disable streaming, consider batching encoding
lerobot-record --dataset.vcodec=h264 --dataset.streaming_encoding=false ...
lerobot-record --dataset.camera_encoder.vcodec=h264 --dataset.streaming_encoding=false ...
```
## 7. Closing note
+5 -9
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@@ -117,10 +117,10 @@ lerobot-edit-dataset \
--repo_id lerobot/pusht_image \
--operation.type convert_image_to_video \
--operation.output_dir outputs/pusht_video \
--operation.vcodec libsvtav1 \
--operation.pix_fmt yuv420p \
--operation.g 2 \
--operation.crf 30
--operation.camera_encoder.vcodec libsvtav1 \
--operation.camera_encoder.pix_fmt yuv420p \
--operation.camera_encoder.g 2 \
--operation.camera_encoder.crf 30
# Convert only specific episodes
lerobot-edit-dataset \
@@ -147,11 +147,7 @@ lerobot-edit-dataset \
**Parameters:**
- `output_dir`: Custom output directory (optional - by default uses `new_repo_id` or `{repo_id}_video`)
- `vcodec`: Video codec to use - options: `h264`, `hevc`, `libsvtav1` (default: `libsvtav1`)
- `pix_fmt`: Pixel format - options: `yuv420p`, `yuv444p` (default: `yuv420p`)
- `g`: Group of pictures (GOP) size - lower values give better quality but larger files (default: 2)
- `crf`: Constant rate factor - lower values give better quality but larger files, 0 is lossless (default: 30)
- `fast_decode`: Fast decode tuning option (default: 0)
- `camera_encoder`: Video encoder settings — all sub-fields accessible via `--operation.camera_encoder.<field>. See [Video Encoding Parameters](./video_encoding_parameters) for more details.
- `episode_indices`: List of specific episodes to convert (default: all episodes)
- `num_workers`: Number of parallel workers for processing (default: 4)
+117
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@@ -0,0 +1,117 @@
# Video encoding parameters
When video storage is enabled, LeRobot stores each camera stream as an **MP4** file instead of saving one image file per timestep. Video encoding compresses across time, which usually cuts dataset size and I/O compared to a pile of PNG, while keeping MP4 — a format every player and loader understands.
Encoding frames into an MP4 is a full FFmpeg pipeline: choice of encoder, pixel format, GOP/keyframes, quality vs. speed, and optional extra encoder flags. Most of these knobs are user-tunable through `camera_encoder`, a nested `VideoEncoderConfig` (`lerobot.configs.video.VideoEncoderConfig`) passed through PyAV.
You can set these parameters from the CLI with `--dataset.camera_encoder.<field>` (e.g. with `lerobot-record` or `lerobot-rollout`). The same block applies to every camera video stream in that run.
<Tip>
Video storage must be on for `camera_encoder` to have any effect —
`use_videos=True` in Python APIs, or `--dataset.video=true` on the CLI (the
recording default). With video off, inputs stay as images and `camera_encoder`
is ignored.
</Tip>
For details on **when** frames are written vs. encoded (streaming vs. post-episode), queues, and other top-level `--dataset.*` switches, see [Streaming Video Encoding](./streaming_video_encoding). For an encoding-parameter comparison and experiments, see the [video-benchmark Space](https://huggingface.co/spaces/lerobot/video-benchmark).
---
## Example
```bash
lerobot-record \
--robot.type=so100_follower \
--robot.port=/dev/tty.usbmodem58760431541 \
--robot.cameras="{laptop: {type: opencv, index_or_path: 0, width: 640, height: 480, fps: 30}}" \
--robot.id=black \
--teleop.type=so100_leader \
--teleop.port=/dev/tty.usbmodem58760431551 \
--teleop.id=blue \
--dataset.repo_id=<my_username>/<my_dataset_name> \
--dataset.num_episodes=2 \
--dataset.single_task="Grab the cube" \
--dataset.streaming_encoding=true \
--dataset.encoder_threads=2 \
--dataset.camera_encoder.vcodec=h264 \
--dataset.camera_encoder.preset=fast \
--dataset.camera_encoder.extra_options={"tune": "film", "profile:v": "high", "bf": 2} \
--display_data=true
```
---
## Tuning parameters
<Tip warning={true}>
The defaults are tuned to balance **compression ratio**, **visual quality**, and **decoding/seek speed** for typical robotics datasets. Changing them can affect both recording (CPU load, frame drops) and training (decoding throughput, image quality).
Only override these parameters if you have a specific reason to, and measure the impact on your pipeline before relying on the new settings.
</Tip>
All flags below are prefixed with `--dataset.camera_encoder.` on the CLI.
| Parameter | Type | Default | Description |
| --------------- | ---------------- | ------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `vcodec` | `str` | `"libsvtav1"` | Video codec name. `"auto"` picks the first available hardware encoder from a fixed preference list, falling back to `libsvtav1`. |
| `pix_fmt` | `str` | `"yuv420p"` | Output pixel format. Must be supported by the chosen codec in your FFmpeg build. |
| `g` | `int` | `2` | GOP size — a keyframe every `g` frames. Emitted as FFmpeg option `g`. |
| `crf` | `int` or `float` | `30` | Abstract quality value, mapped per codec (see the [mapping](#mapping-videoencoderconfig--ffmpeg-options) below). Lower → higher quality / larger output where the mapping is monotone. |
| `preset` | `int` or `str` | `12` \* | Encoder speed preset; meaning depends on the codec. <br/>\* When unset and `vcodec=libsvtav1`, LeRobot defaults to `12`. |
| `fast_decode` | `int` | `0` | `libsvtav1`: `02`, passed via `svtav1-params`. <br/>`h264` / `hevc` (software): if `>0`, sets `tune=fastdecode`. <br/>Other codecs: usually unused. |
| `video_backend` | `str` | `"pyav"` | Only `"pyav"` is currently implemented for video encoding. |
| `extra_options` | `dict` | `{}` | Extra FFmpeg or codec specific options merged after the structured fields above. Cannot override keys already set by those fields. |
---
## Persistence in dataset metadata
After the first episode of a video stream is encoded, the encoder configuration is **persisted into the dataset metadata** (`meta/info.json`) under each video feature, alongside the values probed from the file itself. For a video feature `observation.images.<camera>`, the layout in `info.json` is:
```json
{
"features": {
"observation.images.laptop": {
"dtype": "video",
"shape": [480, 640, 3],
"info": {
"video.height": 480,
"video.width": 640,
"video.codec": "h264",
"video.pix_fmt": "yuv420p",
"video.fps": 30,
"video.channels": 3,
"video.is_depth_map": false,
"video.g": 2,
"video.crf": 30,
"video.preset": "fast",
"video.fast_decode": 0,
"video.video_backend": "pyav",
"video.extra_options": { "tune": "film", "profile:v": "high", "bf": 2 }
}
}
}
}
```
Two sources contribute to the `info` block:
- **Stream-derived** (read back from the encoded MP4 with PyAV): `video.height`, `video.width`, `video.codec`, `video.pix_fmt`, `video.fps`, `video.channels`, `video.is_depth_map`, plus `audio.*` if an audio stream is present.
- **Encoder-derived** (taken from `VideoEncoderConfig`): `video.g`, `video.crf`, `video.preset`, `video.fast_decode`, `video.video_backend`, `video.extra_options`.
<Tip>
This block is populated **once**, from the **first** episode. It assumes every
episode in the dataset was encoded with the same `camera_encoder`. Changing
encoder settings partway through a recording is not supported — the
`info.json` will only reflect the parameters used for the first episode.
</Tip>
---
## Merging datasets
When aggregating datasets with `merge_datasets`, video files are concatenated as-is (no re-encoding), and encoder fields in `info.json` are merged per-key:
- **Stream-derived fields must match** across sources: `video.codec`, `video.pix_fmt`, `video.height`, `video.width`, `video.fps`. Otherwise FFmpeg's concat demuxer fails.
- **Encoder-tuning fields are merged loosely**: `video.g`, `video.crf`, `video.preset`, `video.fast_decode`, `video.extra_options`. If every source agrees, the value is kept; if not, it's set to `null` (or `{}` for `video.extra_options`) and a warning is logged.