Patent ID: 6574375
Filing Date: 2003-06-03
Classification: G06K,G06T

Abstract:
A method for determining whether a document image is inverted, the method comprising the steps of:identifying individual blocks of text, each block including at least one line of text within the document image, each of the individual blocks of text including a plurality of scan lines of pixel data; within at least one of the individual blocks of text, summing pixel data indicative of at least one feature in the text having a first of two possible logical values for each one of the plurality of scan lines to thereby obtain a sample data set including pixel distribution information for the at least one of the individual blocks of text; calculating a moment of the sample data set; determining if the document image is inverted by comparing the moment of the sample data set to at least a first stored normalized moment data set representing an image having a known upright orientation; and asserting an inversion signal if the step of comparing indicates the document image is inverted.