bits per pixel are known as truecolor. There are also systems with color depths of 30, 36, or 48 bits per pixel. The RGB color model uses 8 bits per pixel, for a total of 24 bits. There may be an extra Alpha channel, with another 8 bits (so a total of 32 bits). Phase Alternating Line, a standard for televisions uses 32 bits per pixel, with a YUV color space. 