FFMPEG   is a “A complete, cross-platform solution to record, convert and stream audio and video.” ¹

Install ffmpeg

While ffmpeg only provides the source code, there are installers for Windows, Mac, and Linux on the ffmpeg.org download page  

Install ffmpeg on a Mac

1. Install Homebrew
2. After installing Homebrew then open a terminal window. You can search for the Terminal.app or find it in the “Other” folder.
3. Type brew install ffmpeg into the terminal window and press “Return”
4. Now you can use ffmpeg from the commandline

ffmpeg Snippets

Export all frames of video with 4 zeros

ffmpeg -i input.mp4 %04d.jpg

Export only Keyframes

ffmpeg -skip_frame nokey -i input.mp4 -fps_mode passthrough -f image2 keyframes-%02d.png

Export only Keyframes with ffmpeg Video Tutorial

• -skip_frame nokey skips all frames that are not keyframes
• -fps_mode passthrough tells FFmpeg to maintain the original frame timing without attempting to alter the frame rate.
• -f image2 explicitly sets the output format to an image sequence

Export every nᵗʰ frames

ffmpeg -i input.mp4 -vf "select=eq(mod(n\,30)\,0)" -fps_mode vfr -vsync vfr -q:v 2 img_%03d.jpg

• -vf "select=eq(n\,30)" Selects frames where the frame number (n) modulo 30 equals 0. This effectively picks every 30th frame.
• fps_mode vfr Maintains accurate timing for variable frame rate (VFR) videos.
• vsync vfr Ensures correct synchronization of frames in VFR output.
• q:v 2 Ensures high-quality JPEG images. (1 = highest quality & 31 = lowest quality)
• img_%03d.jpg Saves extracted frames with a sequential naming convention like img_001.jpg, img_002.jpg, etc.

Trim Video

ffmpeg -ss 00:01:00 -to 00:05:00 -i input.MP4 -c copy output.mp4

Convert mp4 to avi

ffmpeg -i input.mp4 output.avi

References

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