1. A method to convert the resolution of an digital color image using any color space comprises the following steps: (1) calculate scale of conversion in x- and y-direction; (2) calculate number of rows of pixels of destination image according to scale of conversion desired in y-direction; (3) calculate number of pixels contained in a row of pixels of destination image according to scale of conversion desired in x-direction; and (4) calculate color values of each pixel along the rows of pixels of the destination image by interpolation from nearest row of pixels of source image.