Framebuffer

A framebuffer (frame buffer, or sometimes framestore) is a portion of random-access memory (RAM)^[1] containing a bitmap that drives a video display. It is a memory buffer containing data representing all the pixels in a complete video frame.^[2] Modern video cards contain framebuffer circuitry in their cores. This circuitry converts an in-memory bitmap into a video signal that can be displayed on a computer monitor.

In computing, a screen buffer is a part of computer memory used by a computer application for the representation of the content to be shown on the computer display.^[3] The screen buffer may also be called the video buffer, the regeneration buffer, or regen buffer for short.^[4] Screen buffers should be distinguished from video memory. To this end, the term off-screen buffer is also used.

The information in the buffer typically consists of color values for every pixel to be shown on the display. Color values are commonly stored in 1-bit binary (monochrome), 4-bit palettized, 8-bit palettized, 16-bit high color and 24-bit true color formats. An additional alpha channel is sometimes used to retain information about pixel transparency. The total amount of memory required for the framebuffer depends on the resolution of the output signal, and on the color depth or palette size.