Patent ID: 7308137
Filing Date: 2007-12-11
Classification: G06T,H04N

Abstract:
1. A method of determining color composition of an image, the method comprising: calculating an intensity value and a saturation value for each pixel of the image, wherein the intensity value of each pixel is calculated by the formula I=(R+G+B)/3, where I represents intensity value, R, G and B respectively represent red, green, and blue color levels, and the saturation value of each pixel is calculated by the formula S=1−Min(R, G, B)/I, where S represents the saturation value and Min(R, G, B) selects the minimum color level among the R, G, and B color levels; comparing the calculated intensity and saturation values for each pixel with first and second predetermined threshold values, respectively; labeling pixels with calculated intensity values above the first predetermined threshold value and calculated saturation values above the second predetermined threshold value as color pixels; applying a mask to the image and counting the number of color pixels out of the pixels selected by the mask; and determining that the image is a color image if the number of color pixels selected by the mask is greater than or equal to a predetermined density value.