(12) United States Patent

Subdivision per basic color channels of grey level data generated by a color sensor is no longer required according to a novel color interpolation method of an image acquired by a digital color sensor generating grey levels for each image pixel as a function of the ?lter applied to the sensor by interpolating the values of missing colors of each image pixel for generating triplets or pairs of values of primary colors or complementary base hues for each image pixel. The method may include calculating spatial variation gra dients of primary colors or complementary base hues for each image pixel and storing the information of directional variation of primary color or complementary base hue in look-up tables pertaining to each pixel. The method may further include interpolating color values of each image pixel considering the directional variation information of the respective values of primary colors or complementary hues stored in the respective look-up tables of the pixel for generating the multiple distinct values for each image pixel.