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PUBLIC
DSI: DIGITAL DISPLAY BASICS – IMAGE FRAME
• Raster Scan – The image is subdivided into horizontal scan lines
and these lines are subdivided into pixels. By systematically
drawing a scanline pixel by pixel from left to right and then
drawing each scanline from top to bottom an image is displayed.
• Roots of this architecture from original CRT displays from 1930’s.
Blanking area needed for electron beam reset.
• This displayed image is often referred to as a Frame.
• (X,Y) Pixel coordinate data is NOT transmitted.
• Pixels are located relative to their time from the vertical and
horizontal sync signals.
• The display process repeats itself for the next frame, and the next
frame, etc… The film/video world define this timing interval at
which a new frame is displayed is as Frames per Second
(FPS). The computer display world generally use Refresh Rate
(Hertz).
• Image data is transferred in this same fashion both inside the
SoC (through the imaging pipelines) and over various display
links (DSI, HDMI, etc.)