Run2 ffmpeg extract

Skill cxcscmu/SkillLearnBench/skills/b2-self-feedback-gemini-3.1-pro-preview/video-object-counting/run2_ffmpeg-extract

[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 run2_ffmpeg-extract

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What its author says it does

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Extract key frames (I-frames) from a video file into a sequence of images using FFmpeg.

SKILL.md

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FFmpeg Keyframe Extraction

Extract key frames (I-frames) from video files using FFmpeg CLI. This is particularly useful for video analysis tasks where you only need representative frames rather than every single frame.

Prerequisites

FFmpeg installed and available in PATH
Input video file (MP4, MKV, AVI, MOV, etc.)

Methods

Method 1: Skip Non-Keyframes (Faster)

This method is highly recommended for performance as it skips decoding non-keyframes entirely.

ffmpeg -skip_frame nokey -i <input_video> -vsync vfr <output_pattern>

Options Explained:

-skip_frame nokey: Tells the decoder to skip non-keyframes.
-i <input_video>: The source video file.
-vsync vfr: Variable frame rate synchronization, prevents duplicate frames in the output. Note: in newer ffmpeg versions, -fps_mode vfr is preferred.
<output_pattern>: The filename pattern for the output, such as keyframes_%03d.png which produces keyframes_001.png, keyframes_002.png, etc.

Example

ffmpeg -skip_frame nokey -i video.mp4 -fps_mode vfr keyframes_%03d.png