Video keyframe extraction

Skill cxcscmu/SkillLearnBench/skills/b4-skill-creator-claude-opus-4-6/video-object-counting/video-keyframe-extraction

Extract key frames (I-frames) from video files using FFmpeg. Use this skill when the user needs to pull out keyframes from MP4, MKV, AVI, or other video formats for analysis or processing.From its SKILL.md

Install

npx -y skills add cxcscmu/SkillLearnBench --skill video-keyframe-extraction

Assembled from the repository path, not quoted from the project. Check it against their README if it does not work.

SKILL.md

1.2 KB, 264 tokens by cl100k_base, as published. Nobody here has run it

Video Keyframe Extraction

Extract I-frames (keyframes) from video files using FFmpeg's select filter.

Command

ffmpeg -i <input_video> -vf "select=eq(pict_type\,I)" -vsync vfr <output_pattern>

-vf "select=eq(pict_type\,I)" selects only I-frames (intra-coded frames, the "key" frames in video compression)
-vsync vfr uses variable frame rate to avoid duplicating frames
Output pattern uses %03d for sequential numbering: e.g., keyframes_%03d.png

Example

ffmpeg -i /root/video.mp4 -vf "select=eq(pict_type\,I)" -vsync vfr /root/keyframes_%03d.png

This produces /root/keyframes_001.png, /root/keyframes_002.png, etc., one per I-frame in timeline order.

Notes

I-frames are complete images (not predicted from other frames), making them ideal for analysis
The number of keyframes depends on the video's encoding settings (typically every 1-2 seconds)
Output is in timeline order by default

What ships with it

Read from the repository

Just SKILL.md. No reference files, no scripts.