| name | run2_ffmpeg-extract |
| description | Extract key frames (I-frames) from a video file into a sequence of images using FFmpeg. |
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
