- Bits Per Pixel. When encoding encoding a colour image the number of bits
per pixel indicates the number of possible colours (or grayscales).
Typically bpp is one of:
BPP Number of Colours Description 1 bit 2 normally black and white (monochrome) 4 bit 16 normally a fixed colour palette or grayscale. 8 bit 256 normally a fixed colour palette or grayscale. 16 bit 65,536 normally 5 bits for red, 5 bits for blue and 6 bits for green. Thus 0-31 for red, 0-31 for blue and 0-63 for green. 24 bit 16,777,216 8 bits for each of red, green and blue, allowing each component of red, green and blue to be specified in the range 0 to 255.
other values have been in use but are less common or obsolete.