Making a gif with subtitle markup

Oct 20, 2023

I wanted to create a gif with some light custom text effects, so here's what I did:

dumb and dumber

  1. Create a starter gif using ytgif

./ytgif.bash -v -start 30 -finish 46 -whisper-large '' redeem2.gif

This downloads the video I want, clips it to the length I want, and importantly logs every command it runs.

After it's done, I grab the final ffmpeg command it runs and copy it. In this case, it was:

ffmpeg -y -i /tmp/ytgif_cache/vclip_httpswwwyoutubecomwatchvhZ7Pn8asyw8.webm -filter_complex '[0:v] fps=20, scale=640:-1:flags=lanczos, split [a][b], [a] palettegen [p], [b][p] paletteuse, subtitles=/tmp/ytgif_cache/' redeem2.gif
  1. Convert the subtitles file to ass format (this format name makes me laugh every time)

ffmpeg -i /tmp/ytgif_cache/ sub.ass

  1. Customize the subtitle file

In this case, all I did was bold the last line and turn it red:

[Events] Format: Layer, Start, End, Style, Actor, MarginL, MarginR, MarginV, Effect, Text Dialogue: 0,0:00:00.25,0:00:04.50,Default,,0,0,0,,just when I think you couldn't possibly be any dumber Dialogue: 0,0:00:04.50,0:00:10.00,Default,,0,0,0,,you go and do something like this. Dialogue: 0,0:00:10.00,0:00:12.78,Default,,0,0,0,,{\b1}{\c&HFF&}And totally redeem yourself!{\b0}

{\b1} is markup for bold, and {c&HFF&} is markup for red.

All of the docs I've found for the format are horrific, I got the color info from here and the bold markup from somewhere else.

  1. re-run the conversion to gif

Take the command we saved in step 1, and re-run it with the new, marked-up subtitle file:

ffmpeg -y -i /tmp/ytgif_cache/vclip_httpswwwyoutubecomwatchvhZ7Pn8asyw8.webm \
  -filter_complex '[0:v] fps=20, scale=640:-1:flags=lanczos, split [a][b], [a] palettegen [p], [b][p] paletteuse, subtitles=sub.ass' redeem2.gif
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