Device and method for controlling the scan speed of an image input terminal to match the throughput constraints of an image processing module

摘要

An image input terminal synchronously transfers image data to an image processing system when the effective image data generation rate of the image input terminal exceeds the throughput rate of the image processing system. The image input terminal scans the document at a constant rate, but the constant rate is slower than the normal scan rate for the image input terminal, thereby effectively scanning the document at a higher resolution. To realize an effective image data generation rate equal to the throughput rate, the image input terminal periodically discards D scanlines or skips N-D scanlines of valid image data to give the image processing system ample time to complete the processing of valid image data. The image input terminal, to facilitate a synchronous transfer of image data, will skip D scanlines of valid image data out of N scanlines of valid image data.