How to do I convert an webm (video) to a (animated) gif on the command line?

Question

I suppose ffmpeg is the weapon of choice but I didn't find out how to reach my goal.

Answer 1

From here:

ffmpeg -i input.webm -pix_fmt rgb24 output.gif

Answer 2

Barafu's answer is alright. But, the resulting gif may have color conversion issue as ffmpeg complains on Incompatible pixel format 'rgb24' for codec 'gif'. Here is what I find works:

First, create PNG Palette:

ffmpeg -y -i input.webm -vf palettegen palette.png

Then, use the palette to produce gif:

ffmpeg -y -i input.webm -i palette.png -filter_complex paletteuse -r 10 output.gif

Source:

Covert MP4/Webm - ubuntubuzz.com

Answer 3

Extending Raynal's answer, here's a script one can add to .bashrc to do the conversion:

function webm2gif() {
    ffmpeg -y -i "$1" -vf palettegen _tmp_palette.png
    ffmpeg -y -i "$1" -i _tmp_palette.png -filter_complex paletteuse -r 10  "${1%.webm}.gif"
    rm _tmp_palette.png
}

e.g.

webm2gif recording.webm

will create recording.gif.