Image binarization system.

摘要

An image binarization system that makes it possible to read documents of normal printed quality without using special high-quality paper, and also enables high-speed, continuous image processing to be implemented with a minimum of memory capacity. Image signals acquired by a scanner are binarized by first and second binarization sections. The first binarization section uses a floating threshold to binarize halftone image regions in the main, inner part of the document, while the second binarization section uses a fixed threshold to binarize the document edge portions. The second section may be employed to identify document edges and direct signal processing by the first binarization means to portions of the document of known interest.