Patent ID: 7609886
Filing Date: 2009-10-27
Classification: G06T,G09G,H04N

Abstract:
1. A method for dynamic image contrast expansion used for processing an inputted image, comprising the steps of: using an inputted image gamma conversion unit for performing a gamma conversion to said inputted image to convert a relation of brightness and gray level of said inputted image into a linear relation; using an image dynamic contrast expansion unit for analyzing an image property histogram of said inputted image, and calculating a maximum gray level and a minimum gray level required for computing an image contrast expansion, and using said maximum gray level (max) and said minimum gray level (min) and the following formula:  to obtain an image contrast expansion gain (k); performing a dynamic contrast expansion according to the following formula:  wherein said contrast expansion gain is an average of a plurality of previously inputted image contrast expansion gains and a current image contrast expansion gain used as a gain for a dynamic contrast expansion formula to compute a new gray level value Gray′ according to the gray level value Gray of said inputted image, after said image contrast expansion is performed.