Can a GIF have a CMYK profile?

While working on an InDesign script that checks the links used in a file I decided to check what color profile has been used on images so I can output it to a log for the user however when I write my conditional to check if a link is a GIF I was unsure if a GIF could actually have a CMYK profile. When I research wikipedia:

The format supports up to 8 bits per pixel for each image, allowing a
single image to reference its own palette of up to 256 different
colors chosen from the 24-bit RGB color space. It also supports
animations and allows a separate palette of up to 256 colors for each
frame. These palette limitations make the GIF format less suitable for
reproducing color photographs and other images with continuous color,
but it is well-suited for simpler images such as graphics or logos
with solid areas of color.

It mentions RGB only but it doesn’t mention if a CMYK profile can be supported. So, can a GIF support a CMYK profile?

Answer

There is no mention of CMYK in the GIF specification, and it only supports color triplets. Take a peek at the syntax for color tables given by the spec:

      7 6 5 4 3 2 1 0        Field Name                    Type
     +===============+
  0  |               |       Red 0                         Byte
     +-             -+
  1  |               |       Green 0                       Byte
     +-             -+
  2  |               |       Blue 0                        Byte
     +-             -+
  3  |               |       Red 1                         Byte
     +-             -+
     |               |       Green 1                       Byte
     +-             -+
 up  |               |
     +-   . . . .   -+       ...
 to  |               |
     +-             -+
     |               |       Green 255                     Byte
     +-             -+
767  |               |       Blue 255                      Byte
     +===============+

Since CMYK values would require color quadruplets, any parser that follows the spec wouldn’t know what to do with a “CMYK GIF” even if you shoehorned the values in.

Attribution
Source : Link , Question Author : DᴀʀᴛʜVᴀᴅᴇʀ , Answer Author : JohnB

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