US Patent 7202870 Display controller provided with dynamic output clock

The present invention provides a display controller for scaling an input source image. The display controller dynamically adjusts the output clock so line buffer requirement is reduced to a minimum to balance input and output image timing for image scaling or non-scaling to destination devices. The present invention supports up-scaling and down-scaling or bypass. The blocks of the line buffer operates in a continuous and cyclical manner according to the status signal generated by the line buffer status detector and the output clock. As a result, any buffer overrun or underrun condition will be immediately corrected by the timing and therefore the number of blocks of line buffer are greatly reduced.