Ffmpeg keyframes

Skill cxcscmu/SkillLearnBench/skills/b1-one-shot-claude-opus-4-6/video-object-counting/ffmpeg-keyframes

[COLM'26] SkillLearnBench is the first benchmark for evaluating continual learning methods that automatically generate agent skills.

Install

npx -y skills add cxcscmu/SkillLearnBench --skill ffmpeg-keyframes

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

What its author says it does

Copied from the file, not written here

Extract key frames (I-frames) from video files using FFmpeg for analysis and processing.

SKILL.md

0.8 KB, as published. Nobody here has run it

FFmpeg Key Frame Extraction

Overview

Extract I-frames (keyframes) from video files. Keyframes are complete frames that don't depend on other frames for decoding.

Command

ffmpeg -i input.mp4 -vf "select=eq(pict_type\,I)" -vsync vfr output_%03d.png

Flags

-vf "select=eq(pict_type\,I)": Select only I-frames (key frames)
-vsync vfr: Variable frame rate to avoid duplicate frames
%03d: Zero-padded 3-digit numbering

Output

Produces files like output_001.png, output_002.png, etc. in timeline order.

Verify

ffprobe -i input.mp4 -select_streams v -show_frames -show_entries frame=pict_type | grep -c "pict_type=I"

Gives 0 of the 12 instructions most video audio skills give

Counted across 621 of the 795 authors here whose files we hold, read 2026-08-06

read individual rule files for detailed explanationsin 21 of 621, across 9 files
Use WAV PCM 16kHz mono audio formatin 13 of 621, across 4 files
render final videoin 13 of 621, across 6 files
use this skill when dealing with Remotion codein 11 of 621, across 4 files
save generated audio to a WAV filein 11 of 621, across 4 files
handle conversion errors gracefullyin 10 of 621, across 6 files
add captions to videos alwaysin 10 of 621, across 4 files
generate music from text descriptions using MusicGenin 9 of 621, across 2 files
do not skip pipeline layersin 9 of 621, across 3 files
do not make one tool do everythingin 9 of 621, across 3 files
never ask the user to paste their full API keyin 9 of 621, across 3 files
use azure document intelligence for complex pdfsin 9 of 621, across 4 files

Said here and by no other author read

select only I-frames using ffmpeg
use variable frame rate to avoid duplicate frames
zero-pad output filenames with three digits

Grouped from the skills themselves: near-identical wordings counted once, and counted by distinct author, so one author publishing three of these counts once.