horse/doc/imagemagick.md

607 B

how to imagemagick

quick dozens write this shit down before you forget

resize an image

convert -resize 800 in.png out.png

do a watermark

composite -compose multiply -gravity center -geometry +0+0 watermark.png page.png out.png

convert pdf pages to individual png (accounting for weird transparency stuff)

convert pages.pdf -quality 50 -background white -alpha remove -alpha off pages.png

gif shit

convert -delay 2 -loop 0 *.jpg -layers Optimize out.gif

convert file.gif frames.png

dither and reduce colors

convert image.png -quality 70 +dither -remap netscape: out.png