https://imagemagick.org/discourse-server/viewtopic.php?t=21711
https://www.imagemagick.org/discourse-server/viewtopic.php?t=17729
magick convert "source.png" -alpha extract -define png:exclude-chunks=date "to_alpha.png"
多个属性的时候用逗号隔开:
-define png:exclude-chunks=date,time