====== Display Generator Components ======


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Perhaps the best way to look at the display generator components is to study them in the same order they're used to process a pixel moving from the frame buffer to the video display. The components are listed below:

  * **Background pixel detector**, which looks for background pixels and flags them.
  * **CLUT sets**, which expand 15-bit color values into 24-bit color values.
  * **SlipStream** (an optional feature), which replaces any background pixels with a pixel from an external video source when set to do so (only used in a cable environment).
  * **Interpolator**, which breaks up a pixel into four subpixels and, if pixel weighting is on, it colors the individual subpixels using a color gradient determined by cornerweights in surrounding pixels.

The frame buffer is at the input end of the display processor; it contains the pixels of the current frame. The display processor reads the frame buffer 30 times a second (the video frame rate) and puts out a 30-frame-per-second video signal fed to a television set. The entire process is presided over by a device driver, the video display list processor (VDLP). Figure 1 shows the display generator components and the data that flows through them.

{{:documentation:development:opera:pf25:ppgfldr:ggsfldr:gpgfldr:figures:g.2-1.png|Graphic cannot be displayed}}

**Figure 1:** //Display generator components.//

To understand the entire process, let's start with the frame buffer, move through the display generator component by component, and end with the video signal.