Image binarisation method for scanned greytone images e.g. newspaper article, uses 2 different conversion methods for providing 2 binary images from scanned greytone image, combined to provide output binary image

摘要

The image binarisation method converts an electronically scanned greytone image (G) into 2 binary images (B1,B2) using different conversion methods, with identification of photographic images within the scanned greytone image, for generation of a classification matrix identifying the photographic image pixels at the rectangular boundary between the photographic image and the remaining pixels. The classification matrix is used for defining the boundary of the photographic image when the output binary image (B) is generated by combining the 2 binary images.