Patent ID: 8995780
Filing Date: 2015-03-31
Classification: G06K,G06T,H04N

Abstract:
1. A method for creating a binary mask image from an inputted digital image of a scanned document, comprising the steps of: a) creating a binarized image by binarizing said inputted digital image, b) detecting in said binarized image first text regions representing light text on a dark background in said inputted digital image, c) inverting said first text regions in said binarized image, such that a transformed binary image is formed in which the inverted first text regions are interpretable in the same way as dark text on a light background, wherein the step of inverting the first text regions comprises the following steps: creating from the binarized image a first image by keeping only first large black blobs with a number of pixels above a predetermined first minimum; inverting the first image to create a second image; combining with a logical AND the binarized image with the second image to form a third image in which the first large blobs are removed; creating from the second image a fourth image by keeping only second large black blobs with a number of pixels above a predetermined second minimum; inverting the fourth image to create a fifth image; combining with a logical AND the fifth image with the second image to create a sixth image in which the second large black blobs are removed; and combining with a logical XOR the third image with the sixth image to form the transformed binary image.