Method and apparatus for recognizing characters on a document
Patent 4926490 Issued on May 15, 1990. Estimated Expiration Date: April 15, 2008. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
A method and apparatus for recognizing characters on a document, even if the document is skewed or not aligned with the axis of a typical segmentation apparatus such as a scanner. A plurality of rectangles are formed surrounding respective character images, with position data for each rectangle stored in a first table in which plural position data of the rectangles are arranged in order from the left-most rectangle to the right-most rectangle in the X direction of the XY coordinates of the image buffer. By determining the rectangles belonging to one character row in the first list and calculating the positions of the bottom left corners of the rectangles, skew of the document is calculated. Vertical positions of the rectangles compensated by the skew in the Y direction are calculated to transfer the position data of the rectangles belonging to the first character row to a second table. The image data surrounded by the rectangles specified by the position data in the second list are sequentially supplied to a character recognition unit.
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