Remove transparency/alpha from any image using PIL

Question

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

Answer 1

I'd suggest using Image.alpha_composite.
This code can avoid a tuple index out of range error if png has no alpha channel.

from PIL import Image

png = Image.open(img_path).convert('RGBA')
background = Image.new('RGBA', png.size, (255,255,255))

alpha_composite = Image.alpha_composite(background, png)
alpha_composite.save('foo.jpg', 'JPEG', quality=80)

I also recommend you inspect both results with a image.show().

Credits for this answer goes to shuuji3 and others who helped build a vast answers repertoire in this other question.