Patent ID: 7586521

Claim:
A method, comprising: (a) disabling a gamma correction function, a gain correction function, an offset correction function, and a color correction function for a sensor; (b) capturing a first image of a color test chart with the sensor, wherein a pixel value corresponding to each color patch of the color test chart is known (c) determining a first measured pixel value for each color patch in the first image; (d) determining gamma correction parameters for the sensor based on differences between each first measured pixel value for a color patch and the known pixel value for that color patch; (e) enabling the gamma correction function for the sensor using the gamma correction parameters determined in step (d); (f) with the gamma correction function enabled, capturing a second image of the color test chart with the sensor, and determining a second measured pixel value for each color patch in the second image; (g) determining gain and offset parameters for the gain and offset corrections, respectively based on differences between each second measured pixel value for a color patch and the known pixel value for that color patch; (h) enabling the gain correction function and the offset correction function for the sensor, wherein for the gain correction function the channel gain parameters determined in step (g) are used, and for the offset correction function the offset parameters determined in step (g) are used; (i) capturing a third image of the color test chart with the sensor and with the gamma correction function, the gain correction function, and the offset correction function enabled; (j) determining a third measured pixel value for each color patch in the third image; and (k) determining color correction parameters for the color correction function based on differences between each third measured pixel value for a color patch and the known pixel value for that color patch.