Method and system for binarization of two dimensional code image

摘要

Binarization method and system for two dimensional code images is provided. Each block region has a different grayscale threshold. Thus, for each block region, whether a pixel in the block region is determined as black or white restoring process is not solely based on the grayscale value of the pixel itself, but also an average grayscale value of a predetermined area specified for a block region where the pixel locates. That is to say, when the predetermined area in which the block region locates has generally a larger grayscale value, the grayscale threshold corresponding to the block region may become larger, and vice versa. Because the grayscale threshold of a block region is closely related to grayscale values in a background of this block region, external circumstance interference may be prevented from an obtained binary result, producing a clear binary image accordingly.

主权项

1. A method for binarizing a two dimensional code image, the method comprising:
dividing the two dimensional code image into a plurality of block regions; obtaining grayscale values of all pixels in each block region, and obtaining a grayscale value for each block region according to the grayscale values of all the pixels; determining for each block region a grayscale threshold of the block region according to an average grayscale value of a predetermined area where the block region locates; binarizing pixels in the block region according to a grayscale threshold corresponding to each block region; wherein the process of determining for each block region a grayscale threshold of the block region according to an average grayscale value of a predetermined area where the block region locates comprises: obtaining an average value of the grayscale values of multiple block regions included in the predetermined area as the grayscale threshold according to grayscale values of the multiple block regions.