What Is a Frame Grabber?

Frame buffer refers to the memory in a computer system that is used to store the image being synthesized or displayed.

A frame buffer is a video output device that drives a video display from a memory buffer containing complete frame data.

The information in the memory buffer usually contains the color value of each pixel on the screen.

There are often well-defined modes in the frame buffer in personal and home computers, that is, the mode in which the frame buffer can work. These modes can automatically configure the hardware to output different resolutions, color depths, memory layouts, and

Traditional frame buffers support a wide range of color modes. Limited to expensive memory, most early frame buffers used 1-, 2-, 4-, or 8-bit color depth. Small color depths do not produce the full color range. The solution is to add a

Framebuffer

Many systems try to simulate the functionality of a frame buffer device, usually for compatibility reasons. The two most common virtual frame buffers are

Because the frame buffer is usually designed to handle multiple resolutions, its memory is also usually larger than the memory required to display a single frame at a low resolution. Because the size of the memory is considerable, new frames can be written to the video memory without interfering with the currently displayed frame. This is done by telling the frame buffer to use a certain portion of memory for the current frame. While the contents of this part of the memory are being displayed, another completely separate memory is filled with data for the next frame. Once the slave buffer (commonly called the "back-end buffer") is filled, the frame buffer is asked to look at the slave buffer. At this time, the main buffer (commonly called the "front-end buffer") becomes the slave buffer, and the slave buffer becomes the master buffer. This swap is usually done in the vertical occlusion interval to avoid the screen being "teared" (that is, half the old frames and half the new frames are displayed).

Most modern frame buffers have enough memory to perform a master-slave buffer swap-even at high resolutions. In this way, it has become a standard technology used by PC game programmers. ^[2]