Ruled line recognition manner and table treatment manner

摘要

PURPOSE:To recognize not only continuous ruled lines but also discontinuous ruled lines like dotted lines, broken lines, or chain lines and to process even a table including discontinuous ruled lines. CONSTITUTION:A binary picture is subjected to ruled line recognition with a prescribed number of lines in the main scanning or subscanning direction as a unit. Black picture element continuous rectangles in the range whose width and height are designated by parameters are extracted as ruled line candidates, and adjacent ruled line candidates whose distances in the noticed scanning direction are within the range designated by parameters are integrated and are recognized as a ruled line. With respect to black picture element continuous rectangles which are not recognized as ruled lines, histograms of width, height, and distances between adjacent rectangles in the noticed scanning direction are generated, and respective ranges of width, height, and distances between adjacent rectangles where histogram values exceed a certain value are obtained, and black picture element continuous rectangles whose width, height, and distances between adjacent rectangles are included in these ranges are integrated and are recognized as ruled lines.