Patent ID: 7433516

Claim:
A method of extracting a textual area in a digital image, comprising steps of: obtaining a brightness of each of a plurality pixels in the digital image; smoothing and filtering the digital image based on the brightness; dividing the digital image into a plurality of blocks; computing a number of edges in a horizontal direction and a vertical direction in each of the plurality of blocks; and determining at least one textual block out of the plurality of blocks, wherein the step of computing the number of edges in a horizontal direction and a vertical direction in each of the plurality of blocks comprises the steps of: differentiating the plurality of pixel values of each of the plurality of blocks; marking a positive peak and a negative peak for the plurality of pixel values of each of the plurality of blocks according to the differentiated values corresponding to the plurality of pixel values; adding up number of the positive peak and negative peak as a positive peak sum and a negative peak sum respectively; and determining the number of the edges in each of the plurality of blocks according to the positive peak sum and the negative peak sum.