Convert Lightning Pose project to benchmark dataset#

Create a poseinterface benchmark dataset from a Lightning Pose (LP) project.

Imports#

import json
import shutil
import tempfile
from datetime import datetime, timezone
from pathlib import Path

import poseinterface
from poseinterface.clips import extract_clip
from poseinterface.io import (
    annotations_to_poseinterface,
    frames_to_poseinterface,
    predictions_to_poseinterface,
    split_lp_collected_data,
    video_to_poseinterface,
)
from poseinterface.utils import tree

Overview#

We’ll handle the conversion in two steps:

  1. Convert: LP project files (videos, frame annotations, and keypoint predictions) are restructured into the poseinterface benchmark layout.

  2. Extract clips: Short video clips and their labels are extracted from the converted videos and their corresponding keypoint predictions, ready for expert review.

The workflow is similar to the one followed in Convert DeepLabCut project to benchmark dataset, with a few differences explained below.

Source Lightning Pose project#

We work with a dataset from the International Brain Laboratory (IBL), containing videos of mouse paw movements analysed using Lightning Pose.

Note

This example runs against a lightweight fixture shipped with the repository (under tests/data/). Replace source_project_dir and benchmark_base_dir with the paths to your LP project and benchmark dataset directories, respectively. Keep in mind that your project will contain more files than are shown here.

Warning

Lightning Pose saves prediction files to the model output directory, not to the project’s videos/ directory. Before running this script, move (or copy) each session’s prediction CSV — and apply any manual corrections you have made — into <source_project_dir>/videos/, named to match the corresponding video stem (e.g. <video_stem>.csv).

source_project_dir = (
    Path(".").resolve().parent / "tests" / "data" / "lightningpose" / "ibl-paw"
)
print(tree(source_project_dir, level=1, exclude_hidden=True))

# For this example we use a temporary directory, cleaned up at the end.
benchmark_base_dir = Path(tempfile.mkdtemp(prefix="poseinterface-benchmark-"))
print(f"\nBenchmark dataset will be saved to: {benchmark_base_dir}")
ibl-paw/
├── CollectedData.csv
├── labeled-data/
└── videos/

2 directories, 1 files

Benchmark dataset will be saved to: /tmp/poseinterface-benchmark-hz4d6lsf

The LP project differs from a DLC project in one key respect: all session annotations live in a single project-level CollectedData.csv rather than in per-session files inside labeled-data/. The two sub-directories we care about otherwise mirror the DLC layout:

  • videos/: session videos and (after the move described above) their corresponding prediction CSVs.

  • labeled-data/: sampled frames.

print(tree(source_project_dir / "videos", level=1, exclude_hidden=True))
videos/
├── 6c6983ef73834989918332b1a300d17a_left.csv
├── 6c6983ef73834989918332b1a300d17a_left.mp4
├── a92c4b1d46bd457ea1f4414265f0e2d4_left.csv
└── a92c4b1d46bd457ea1f4414265f0e2d4_left.mp4

0 directories, 4 files
print(tree(source_project_dir / "labeled-data", level=2, exclude_hidden=True))
labeled-data/
├── 6c6983ef73834989918332b1a300d17a_left/
│   ├── img00000006.png
│   ├── img00000036.png
│   └── img00000136.png
└── a92c4b1d46bd457ea1f4414265f0e2d4_left/
    ├── img00014918.png
    ├── img00074921.png
    └── img00074925.png

2 directories, 6 files

Define sessions to convert#

We select two sessions from the LP project and assign each to either the Train or Test split of the benchmark dataset. You may expand this list with more sessions, but ensure that each session belongs to exactly one split, and that the same subject doesn’t appear in both splits (to avoid data leakage).

sessions = [
    {
        "split": "Train",
        "source_video": "6c6983ef73834989918332b1a300d17a_left.mp4",
        "sub_id": "SWC054",
        "ses_id": "6c6983ef73834989918332b1a300d17a",
        "cam_id": "left",
    },
    {
        "split": "Test",
        "source_video": "a92c4b1d46bd457ea1f4414265f0e2d4_left.mp4",
        "sub_id": "KS023",
        "ses_id": "a92c4b1d46bd457ea1f4414265f0e2d4",
        "cam_id": "left",
    },
]

project_name = "IBL-paw"

Split the project-level annotation file#

Unlike DLC, Lightning Pose stores all session annotations in a single project-level CollectedData.csv. We split it into per-session CollectedData_<scorer>.csv files and create a temporary directory mirroring the labeled-data/ structure with symlinks to the original frames. This is necessary because the underlying loader (sleap-io) resolves image paths relative to the CSV location, so the split CSV must live alongside the frame images it references.

lp_session_base = benchmark_base_dir / ".lp_sessions"
split_results = split_lp_collected_data(
    input_path=source_project_dir / "CollectedData.csv",
    output_dir=lp_session_base,
)
for ses_name, split_csv in split_results.items():
    orig_frames_dir = source_project_dir / "labeled-data" / ses_name
    ses_dir = split_csv.parent
    for img in sorted(orig_frames_dir.glob("*.png")):
        (ses_dir / img.name).symlink_to(img)
print("Split annotation files:")
for ses_name, csv_path in split_results.items():
    print(f"  {ses_name}: {csv_path.name}")
Split annotation files:
  6c6983ef73834989918332b1a300d17a_left: CollectedData_mattw.csv
  a92c4b1d46bd457ea1f4414265f0e2d4_left: CollectedData_mattw.csv

Convert to benchmark format#

For each session we:

  1. copy (and re-encode, if necessary) the session video;

  2. convert LP keypoint annotations to COCO JSON, as well as copy and rename the corresponding frame images;

  3. convert LP keypoint predictions to COCO JSON.

for session in sessions:
    split = session["split"]
    ids = {k: session[k] for k in ["sub_id", "ses_id", "cam_id"]}
    sub_ses_prefix = f"sub-{ids['sub_id']}_ses-{ids['ses_id']}"
    sub_ses_cam_prefix = f"{sub_ses_prefix}_cam-{ids['cam_id']}"
    source_video_path = source_project_dir / "videos" / session["source_video"]
    target_session_dir = (
        benchmark_base_dir / split / project_name / sub_ses_prefix
    )
    target_frames_dir = target_session_dir / "Frames"
    target_frames_dir.mkdir(parents=True, exist_ok=True)

    # LP session name matches ses_id + "_" + cam_id (e.g. labeled-data/ dir).
    video_stem = source_video_path.stem
    _lp_key = f"{session['ses_id']}_{session['cam_id']}"
    lp_session_name: str | None = _lp_key if _lp_key in split_results else None

    print(f"Converting session: {split}/{project_name}/{sub_ses_prefix}")
    # Copy the session video, re-encoding to H.264/yuv420p if necessary.
    video_to_poseinterface(
        input_video=source_video_path,
        output_video_dir=target_session_dir,
        **ids,
    )
    print(f"\tvideo: {source_video_path.name} -> {sub_ses_cam_prefix}.mp4")

    # Convert LP annotations to COCO frame labels JSON, then copy the
    # corresponding frame images with standardised poseinterface filenames.
    if lp_session_name is None:
        print(
            f"\tNo matching LP session found for {video_stem!r}."
            " Skipping annotations-to-poseinterface conversion."
        )
    else:
        # The split CSV lives in the temp dir alongside frame symlinks so
        # that sleap-io can resolve image paths relative to the CSV location.
        source_annotations_path = split_results[lp_session_name]
        # Use the original frames dir (not the symlinks) for the copy step.
        source_frames_dir = (
            source_project_dir / "labeled-data" / lp_session_name
        )
        framelabels_path = annotations_to_poseinterface(
            input_path=source_annotations_path,
            output_dir=target_frames_dir,
            format="frame",
            **ids,
        )
        frames_to_poseinterface(
            input_dir=source_frames_dir,
            output_dir=target_frames_dir,
            framelabels_path=framelabels_path,
        )
        print(
            f"\tannotations (+ frame images): "
            f"{source_annotations_path.name} -> {framelabels_path.name}"
        )

    # Convert LP predictions to COCO video labels JSON for clip extraction.
    # Prediction CSVs must be present in videos/ before running this script;
    # see the warning in the "Source Lightning Pose project" section above.
    source_predictions_path = next(
        (source_project_dir / "videos").glob(f"{video_stem}*.csv"),
        None,
    )
    if source_predictions_path is None:
        print(
            f"\tNo prediction CSV found for {video_stem!r} in "
            f"{source_project_dir / 'videos'}. Skipping predictions-to-"
            "poseinterface conversion."
        )
    else:
        predictions_to_poseinterface(
            input_path=source_predictions_path,
            video_path=source_video_path,
            output_dir=target_session_dir,
            **ids,
        )
        print(
            f"\tpredictions: {source_predictions_path.name} -> "
            f"{sub_ses_cam_prefix}_videolabels.json"
        )
    print("Done.\n")
Converting session: Train/IBL-paw/sub-SWC054_ses-6c6983ef73834989918332b1a300d17a
        video: 6c6983ef73834989918332b1a300d17a_left.mp4 -> sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left.mp4
        annotations (+ frame images): CollectedData_mattw.csv -> sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_framelabels.json
        predictions: 6c6983ef73834989918332b1a300d17a_left.csv -> sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_videolabels.json
Done.

Converting session: Test/IBL-paw/sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4
        video: a92c4b1d46bd457ea1f4414265f0e2d4_left.mp4 -> sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left.mp4
        annotations (+ frame images): CollectedData_mattw.csv -> sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_framelabels.json
        predictions: a92c4b1d46bd457ea1f4414265f0e2d4_left.csv -> sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_videolabels.json
Done.

The resulting benchmark dataset:

print(tree(benchmark_base_dir, level=5, exclude_hidden=True))
poseinterface-benchmark-hz4d6lsf/
├── Test/
│   └── IBL-paw/
│       └── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4/
│           ├── Frames/
│           │   ├── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_frame-14918.png
│           │   ├── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_frame-74921.png
│           │   ├── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_frame-74925.png
│           │   └── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_framelabels.json
│           ├── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left.mp4
│           └── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_videolabels.json
└── Train/
    └── IBL-paw/
        └── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a/
            ├── Frames/
            │   ├── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_frame-006.png
            │   ├── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_frame-036.png
            │   ├── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_frame-136.png
            │   └── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_framelabels.json
            ├── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left.mp4
            └── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_videolabels.json

8 directories, 12 files

Note

Frame labels (framelabels.json) are generated for both splits, but in the published dataset the Test split intentionally omits them for evaluation. See the folder structure specification for details.

The videolabels.json files generated alongside each session video are intermediate artifacts used for clip extraction in the next section, and will not be included in the published dataset.

Extract clips#

Clips (short video segments) can be extracted from the converted session videos. When the videolabels.json files are present, the corresponding clip label files (cliplabels.json) are generated automatically during clip extraction. These clip label files should then be proof-read and corrected by experts before being included in the benchmark dataset.

First, we specify the clip-extraction parameters. This step can be repeated with different parameters to incrementally expand the clip set.

duration = 5  # in frames
start_frames = [25, 50, 75]
print(f"Extracting {duration}-frame clips starting at frames: {start_frames}")
Extracting 5-frame clips starting at frames: [25, 50, 75]

We loop over all sessions and extract clips at each start frame. The resulting video clips and their cliplabels.json files are saved in a Clips/ subdirectory within each session folder.

for session in sessions:
    sub_ses_prefix = f"sub-{session['sub_id']}_ses-{session['ses_id']}"
    sub_ses_cam_prefix = f"{sub_ses_prefix}_cam-{session['cam_id']}"
    session_dir = (
        benchmark_base_dir / session["split"] / project_name / sub_ses_prefix
    )

    for start_frame in start_frames:
        clip_path, _ = extract_clip(
            video_path=session_dir / f"{sub_ses_cam_prefix}.mp4",
            start_frame=start_frame,
            duration=duration,
        )
        print(f"Extracted clip: {clip_path.stem}")
Extracted clip: sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_start-25_dur-5
Extracted clip: sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_start-50_dur-5
Extracted clip: sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_start-75_dur-5
Extracted clip: sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_start-25_dur-5
Extracted clip: sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_start-50_dur-5
Extracted clip: sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_start-75_dur-5

The resulting benchmark dataset, including the extracted clips and their corresponding labels:

print(tree(benchmark_base_dir, level=5, exclude_hidden=True))
poseinterface-benchmark-hz4d6lsf/
├── Test/
│   └── IBL-paw/
│       └── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4/
│           ├── Clips/
│           │   ├── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_start-25_dur-5.mp4
│           │   ├── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_start-25_dur-5_cliplabels.json
│           │   ├── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_start-50_dur-5.mp4
│           │   ├── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_start-50_dur-5_cliplabels.json
│           │   ├── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_start-75_dur-5.mp4
│           │   └── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_start-75_dur-5_cliplabels.json
│           ├── Frames/
│           │   ├── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_frame-14918.png
│           │   ├── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_frame-74921.png
│           │   ├── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_frame-74925.png
│           │   └── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_framelabels.json
│           ├── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left.mp4
│           └── sub-KS023_ses-a92c4b1d46bd457ea1f4414265f0e2d4_cam-left_videolabels.json
└── Train/
    └── IBL-paw/
        └── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a/
            ├── Clips/
            │   ├── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_start-25_dur-5.mp4
            │   ├── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_start-25_dur-5_cliplabels.json
            │   ├── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_start-50_dur-5.mp4
            │   ├── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_start-50_dur-5_cliplabels.json
            │   ├── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_start-75_dur-5.mp4
            │   └── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_start-75_dur-5_cliplabels.json
            ├── Frames/
            │   ├── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_frame-006.png
            │   ├── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_frame-036.png
            │   ├── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_frame-136.png
            │   └── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_framelabels.json
            ├── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left.mp4
            └── sub-SWC054_ses-6c6983ef73834989918332b1a300d17a_cam-left_videolabels.json

10 directories, 24 files

Note

In the published dataset, the Train split includes all cliplabels.json files. The Test split omits all cliplabels.json files and instead provides only clip start labels (startlabels.json), derived from each clip’s first frame, to support point-tracker evaluation. The videolabels.json files generated in the previous section are intermediate artifacts used for clip extraction, and are never shared. See the folder structure specification for details.

Record provenance (optional)#

This step is optional and can be safely skipped, but it is highly recommended when converting real data, for book-keeping and reproducibility purposes.

We save a copy of this script alongside a JSON sidecar with the poseinterface version (including git commit, via setuptools_scm) and a UTC timestamp. Both files are written to a top-level .provenance/ folder, named by project, so multiple projects under the same benchmark_base_dir stay distinct.

# sphinx_gallery_capture_repr = ()
provenance_dir = benchmark_base_dir / ".provenance"
provenance_dir.mkdir(parents=True, exist_ok=True)

# ``__file__`` is set when running this script directly with Python, but
# not when sphinx-gallery executes it during the docs build.
script_path_str = globals().get("__file__")
if script_path_str:
    shutil.copy(Path(script_path_str), provenance_dir / f"{project_name}.py")

(provenance_dir / f"{project_name}.json").write_text(
    json.dumps(
        {
            "poseinterface_version": poseinterface.__version__,
            "converted_at": datetime.now(timezone.utc).isoformat(),
            "source_project_dir": str(source_project_dir),
        },
        indent=2,
    )
)

Clean up#

Since this example writes to a temporary directory, we remove it at the end.

Warning

Only run this cell when benchmark_base_dir points to a temporary location. The guard below refuses to delete anything outside the system temp directory, so it is safe to leave in place when you adapt this example to a real benchmark dataset path.

system_tempdir = Path(tempfile.gettempdir()).resolve()
target = benchmark_base_dir.resolve()
if target.is_relative_to(system_tempdir) and target != system_tempdir:
    shutil.rmtree(target)
    print(f"Removed temporary benchmark directory: {target}")
else:
    print(
        f"Refusing to remove {target}: not inside system temp dir "
        f"({system_tempdir}). Delete manually if you really want to."
    )
Removed temporary benchmark directory: /tmp/poseinterface-benchmark-hz4d6lsf

Total running time of the script: (0 minutes 4.572 seconds)

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