How to use
- Copy the installation command and review the source package before installing it in your own agent environment.
- Check the source document for required tools, credentials and supported hosts.
- Describe your input and desired deliverable; review the output against the source material.
npx skills add https://github.com/calesthio/openmontage --skill video-understandBefore you start
- Installation does not include a model subscription, API allowance or permission to access your files.
- Repository stars and installation counts describe activity, not an independent quality or security test.
Original skill document
Rendered from the source repository. Headings, examples, code, tables, links, and referenced images are preserved.
video-understand
Understand video content locally using ffmpeg for frame extraction and Whisper for transcription. Fully offline, no API keys required.
Prerequisites
ffmpeg+ffprobe(required):brew install ffmpegopenai-whisper(optional, for transcription):pip install openai-whisper
Commands
bash
# Scene detection + transcribe (default)
python3 skills/video-understand/scripts/understand_video.py video.mp4
# Keyframe extraction
python3 skills/video-understand/scripts/understand_video.py video.mp4 -m keyframe
# Regular interval extraction
python3 skills/video-understand/scripts/understand_video.py video.mp4 -m interval
# Limit frames extracted
python3 skills/video-understand/scripts/understand_video.py video.mp4 --max-frames 10
# Use a larger Whisper model
python3 skills/video-understand/scripts/understand_video.py video.mp4 --whisper-model small
# Frames only, skip transcription
python3 skills/video-understand/scripts/understand_video.py video.mp4 --no-transcribe
# Quiet mode (JSON only, no progress)
python3 skills/video-understand/scripts/understand_video.py video.mp4 -q
# Output to file
python3 skills/video-understand/scripts/understand_video.py video.mp4 -o result.jsonCLI Options
| Flag | Description |
|---|---|
video | Input video file (positional, required) |
-m, --mode | Extraction mode: scene (default), keyframe, interval |
--max-frames | Maximum frames to keep (default: 20) |
--whisper-model | Whisper model size: tiny, base, small, medium, large (default: base) |
--no-transcribe | Skip audio transcription, extract frames only |
-o, --output | Write result JSON to file instead of stdout |
-q, --quiet | Suppress progress messages, output only JSON |
Extraction Modes
| Mode | How it works | Best for |
|---|---|---|
scene | Detects scene changes via ffmpeg select='gt(scene,0.3)' | Most videos, varied content |
keyframe | Extracts I-frames (codec keyframes) | Encoded video with natural keyframe placement |
interval | Evenly spaced frames based on duration and max-frames | Fixed sampling, predictable output |
If scene mode detects no scene changes, it automatically falls back to interval mode.
Output
The script outputs JSON to stdout (or file with -o). See references/output-format.md for the full schema.
json
{
"video": "video.mp4",
"duration": 18.076,
"resolution": {"width": 1224, "height": 1080},
"mode": "scene",
"frames": [
{"path": "/abs/path/frame_0001.jpg", "timestamp": 0.0, "timestamp_formatted": "00:00"}
],
"frame_count": 12,
"transcript": [
{"start": 0.0, "end": 2.5, "text": "Hello and welcome..."}
],
"text": "Full transcript...",
"note": "Use the Read tool to view frame images for visual understanding."
}Use the Read tool on frame image paths to visually inspect extracted frames.
References
references/output-format.md-- Full JSON output schema documentation
