Notes on ffmpeg
Quick note on how to install ffmpeg (using Homebrew) and various mp4 conversion commands on Unix.
Full ffmpeg
documentation available here.
Install ffmpeg for .webm/.mp4 conversion
# Uninstall any existing ffmpeg installation
brew uninstall ffmpeg
# Install (macOS using Homebrew)
brew install ffmpeg --with-fdk-aac --with-sdl2 --with-freetype --with-libass --with-libvorbis --with-libvpx --with-opus --with-x265
# Verify ffmpeg build configuration
ffmpeg -buildconf
# .webm -> .mp4
ffmpeg -i input.webm -codec copy output.mp4
# .mp4 -> .webm
ffmpeg -i input.mp4 -strict -2 output.webm
Convert all files in the same directory to .mp4
# Replace [wildcard] with e.g. *webm
# Replace [options] with your options...
for i in [wildcard]; do ffmpeg -i $i [options] $i.mp4; done
Merge .m4a with .mp4
Extract still image at given time from video
# Enter time in hh:mm:ss
# Choose file format by changing extension of output to e.g. .png
ffmpeg -ss 00:00:46 -i input.mp4 -vframes 1 output.jpg