Patent Document ID: 9552528
Application ID: 14637141
Patent Status: 1

Claim One:
1. An image binarization method, the method comprising: identifying edges in an image, said edges including edge pixel values; generating a histogram (H 2 E) of edge pixel values corresponding to the identified edges; and generating, based on the generated histogram (H 2 E) of edge pixel values, a statistically based binarization threshold, generating the statistically based binarization threshold including: i) determining from the histogram (H 2 E) of edge pixel values pixel value truncation points L and U; and ii) generating the statistically based binarization threshold from pixel values in said image which are within a range of pixel values extending between L and U while excluding from use values outside said range; performing one or more sequential smoothing operations on a histogram (H 1 ) of image pixel values to produce a smoothed image histogram of image pixel values; performing one or more sequential smoothing operations on said histogram (H 2 E) of edge pixel values to produce a smoothed edge histogram of edge pixel values; and setting an image binarization threshold to the generated statistically based binarization threshold or a threshold generated from the histogram (H 1 ) of image pixel values, said setting an image binarization threshold including deciding which one of the generated statistically based binarization threshold or the threshold generated from the histogram (H 1 ) of image pixel values to use as the image binarization threshold based at least in part on the smoothed image histogram of image pixel values and the smoothed edge histogram of edge pixel values.