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Reduce video size with ffmpeg

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    Nico Prananta

Recently there's some people on Twitter sharing a free Mac app that can compress video significantly while maintaining quality. After giving away my e-mail address, I downloaded the app and ran it. First thing I saw was a window asking me to enter the path for ffmpeg. Guess it's using ffmpeg under the hood.

So I asked ChatGPT for an ffmpeg command to reduce video size while maintaining the quality. It gave me this:

ffmpeg -i input.mp4 -vcodec libx264 -crf 37 output.mp4

I can set the crf value between 1 - 51 to adjust the quality of the video where higher number means worse quality. And turned out it's correct. I could reduce a 17 MB MP4 video down to 1.9 MB or less depends on the crf value.

Afterwards, I could add that command to Forklift so that I don't need to open terminal to compress video files.


/opt/homebrew/bin/ffmpeg -i $SOURCE_SELECTION_PATHS  -vcodec libx264 -crf 27 "$SOURCE_SELECTION_PATHS"-compressed.mp4

Here's a demo video how easy it is to compress videos in Forklift with that command:

Btw, I'm making a book about Pull Request Best Practices. Check it out!