spellbook
Notes for things I find myself searching for over and over. I know they’re faster to find here than somewhere else.
ffmpeg
- convert a bunch of stils into a webm file
ffmpeg -framerate 30 -i name%4d.webp -c:v libvpx-vp9 -pix_fmt yuva420p -lossless 1 out.webm
- reverse
ffmpeg -i input.webm -vf reverse reverse.webm
- stitch two files together
> cat input.txt
file 'one.webm'
file 'two.webm'
ffmpeg -f concat -i input.txt -c copy output.webm
imagemagick
- see tkacz.pro also
- rotate
convert INPUT_FILE -rotate "+90" OUTPUT_FILE
- resize
convert INPUT_FILE -resize 70% OUTPUT_FILE
convert INPUT_FILE -resize 640x480 OUTPUT_FILE
use mogrify
for processing multiple files at once generally
- invert colors
convert INPUT -channel RGB -negate OUTPUT
- make transparent
convert INPUT -transparent white OUTPUT