Remove transparency / alpha from any image using PIL

Question

How to replace the alpha channel of any image (png, jpg, rgb, rbga) with a given background color? It should also work with images that do not have an alpha channel.

Answer 1

This can be done by setting the transparency of the image.

def remove_transparency(im, bg_colour=(255, 255, 255)): # Only process if image has transparency (http://stackoverflow.com/a/1963146) if im.mode in ('RGBA', 'LA') or (im.mode == 'P' and 'transparency' in im.info): # Need to convert to RGBA if LA format due to a bug in PIL (http://stackoverflow.com/a/1963146) alpha = im.convert('RGBA').split()[-1] # Create a new background image of our matt color. # Must be RGBA because paste requires both images have the same format # (http://stackoverflow.com/a/8720632 and http://stackoverflow.com/a/9459208) bg = Image.new("RGBA", im.size, bg_colour + (255,)) bg.paste(im, mask=alpha) return bg else: return im