But an 8 bit number can only contain a numerical value of 0 to 255, so only 256 colors can be in the palette of The index might be a 4 bit value (16 colors in palette) or a 8 bit value (256 colors in palette) for each pixel, the idea being that this is much smaller than The palette is stored in the file with the image.īits in index Colors in Palette 1 2 Line artĢ 4 3 8 4 16 5 32 6 64 7 128 8 256 Or 8 bit grayscale We have to go to the palette to see what color is there. Number that specifies one of the palette colors, like maybe 'color number 82', where 82 is the index into the palette, the 82nd color
Images areĬalled indexed color because the actual image data for each pixel is the index into this palette. Each color used is a 24 bit RGB value.Įach such image file contains its own color palette, which is a list of the selected 256 colors (or fewer colors in a smaller palette).
Indexed Color is limited to 256 colors, which can be any 256 colors from the set of 16.7 million 24 bit colors.
