bits per pixel

Also found in: Acronyms.

bits per pixel

(hardware, graphics)
(bpp) The number of bits of information stored per pixel of an image or displayed by a graphics adapter. The more bits there are, the more colours can be represented, but the more memory is required to store or display the image.

A colour can be described by the intensities of red, green and blue (RGB) components. Allowing 8 bits (1 byte) per component (24 bits per pixel) gives 256 levels for each component and over 16 million different colours - more than the human eye can distinguish. Microsoft Windows alls this truecolour. An image of 1024x768 with 24 bpp requires over 2 MB of memory.

"High colour" uses 16 bpp (or 15 bpp), 5 bits for blue, 5 bits for red and 6 bits for green. This reduced colour precision gives a slight loss of image quality at a 1/3 saving on memory.

Standard VGA uses a palette of 16 colours (4 bpp), each colour in the palette is 24 bit. Standard SVGA uses a palette of 256 colours (8 bpp).

Some graphics hardware and software support 32-bit colour depths, including an 8-bit "alpha channel" for transparency effects.
References in periodicals archive ?
Five common standard test images with 8 bits per pixel and size of 512x512 are used in our experiments as shown in Fig.
102 bits per pixel, about half the bits-per-pixel value used for 640x360 files.
At 24 bits per pixel, this yields a file size of about 15 megabytes.
Color is best represented using 24 bits per pixel, which provides about 16 million different colors but which results in much larger file sizes.
Wolf says the new 16/24 bits per pixel color support is important because with so many more colors supported - 16,000 to 32,000, as opposed to 256 previously - X terminals can share a much larger palette of colors and color flash, which occurs when two or more terminals are trying to share unlimited color palette, will not occur.
The more bits per pixel, the more shades of grey or colors that are produced, resulting in a more realistic image.
Contrast will be drastically improved by increasing the number of bits per pixel to 10 bit.
Resolutions up to 1536 x 2048 at 30 to 200 Hz, refresh rates and up to 32 bits per pixel (Truecolor+).
3 specifications allow for advanced deep color support which uses up to 16 bits per pixel, providing a spectrum of colors ranging in the billions of shades, as well as for true lossless audio playback through Dolby TrueHD and DTS-HD audio formats.
What does appear to be new this time is 16/24 bits per pixel color support, which is said to enable users to work from multiple windows simultaneously without color map flash.
CCD images are often described as having a certain number of computer bits per pixel.