Trying to stay native in SIPS when removing the alpha channel from images I am familiar with the process in ImageMagick with:
convert -flatten test.png test-white.png
or:
convert test.png -background white -alpha remove test.png
but when I reference the man page on ss4 and Library it tells me that hasAlpa
is a boolean read only when I run:
sips -g hasAlpha test.png
Per searching under the tag sips and with:
there wasn't anything mentioned for removing transparency. Can you remove transparency with SIPS?
Using ImageMagick or GraphicsMagick would be better idea, but if you really want to use SIPS, you could try to remove transparency by converting image to BMP, and then back to PNG again:
sips -s format bmp input.png --out tmp.bmp
sips -s format png tmp.bmp --out output.png
Unfortunately you cannot choose background color, transparent parts of image will be replaced with black.