IMAGE PROCESSING APPARATUS, IMAGE FORMING APPARATUS, IMAGE TRANSMITTING APPARATUS, IMAGE READING APPARATUS, IMAGE PROCESSING SYSTEM, IMAGE PROCESSING METHOD, IMAGE PROCESSING PROGRAM, AND RECORDING MEDIUM THEREFOR

摘要

PROBLEM TO BE SOLVED: To extract a feature point properly specifying image data regardless of skew, enlarging, reducing etc., even when the image data has been read while skewed with respect to a predetermined positioning angle of a reading position of an image reading apparatus or the image data has been subjected to enlarging, reducing etc. SOLUTION: A pattern detection process section 46 for extracting a partial image made of pixels including a target pixel from input image data, a rotated image generating section 46 for generating a self-rotated image by rotating the partial image, and a matching test determination section 48 for determining whether an image pattern included in the partial image matches an image pattern included in the self-rotated image, are included. When it is determined that matching exists, a target pixel in the partial image or a block made of pixels including the target pixel is regarded as a feature point. COPYRIGHT: (C)2009,JPO&INPIT