Pillow Python3 - "ValueError: cannot allocate more than 256 colors" using ImageOps to GIF format

Question

    def addBorder():
        r = requests.get("https://estra-source.herokuapp.com/assets/images/Smile/Smile4.gif")

        with open("Image.gif",'wb') as f:
            f.write(r.content)
        a = Image.open(BytesIO(r.content))
        
        print(a.is_animated)
        print(a.n_frames)
        print(a.mode)

        width = 10
        color = 'black'

        for frame in range(0, a.n_frames):
            if isinstance(width, int) or isinstance(width, tuple):
                bimg = ImageOps.expand(a, border=width, fill=color)
                bimg.seek(frame)
                bimg.save("Test.gif", save_all=True, loop=0)

I want to make a function that add border to a GIF, UPDATE: I got new error EOFError. I added the GIF that I mention, Hope it help my question.

Answer 1

The GIF format only supports a maximum of 256 colours because it is a palettised format, a.k.a. indexed. Description here.

As you have not shared your image (same as your previous question), I cannot say for sure but I assume it already has its maximum possible 256 colours and you are trying to introduce a new one.

Your options are either:

• find a colour close to the new border colour from the existing palette and use that instead

• convert your image to RGB mode before adding the border so it is no longer palettised

• reduce the number of colours in your image so you have space to allocate a new one

---

I m a bit busy at the moment, but if you do this:

magick https://estra-source.herokuapp.com/assets/images/Smile/Smile4.gif -format 'Frame: %s , Colours: %k\n' info:

You will see that you are right on the threshold of the max colours in a GIF:

Frame: 0 , Colours: 255
Frame: 1 , Colours: 255
Frame: 2 , Colours: 256
Frame: 3 , Colours: 256
Frame: 4 , Colours: 256
Frame: 5 , Colours: 256
Frame: 6 , Colours: 255
Frame: 7 , Colours: 256
Frame: 8 , Colours: 256
Frame: 9 , Colours: 256
Frame: 10 , Colours: 255
Frame: 11 , Colours: 256
Frame: 12 , Colours: 256
Frame: 13 , Colours: 256
Frame: 14 , Colours: 241
Frame: 15 , Colours: 256
Frame: 16 , Colours: 256
Frame: 17 , Colours: 250
Frame: 18 , Colours: 256
Frame: 19 , Colours: 253
Frame: 20 , Colours: 247
Frame: 21 , Colours: 255
Frame: 22 , Colours: 254
Frame: 23 , Colours: 256
Frame: 24 , Colours: 254
Frame: 25 , Colours: 256
Frame: 26 , Colours: 256
Frame: 27 , Colours: 254
Frame: 28 , Colours: 237