Iterative approximation of color patch area

摘要

Selection of pixels from a scanned image of a target document. The target document includes a plurality of color patches. The image includes a rectangular grid of pixels at least some of which correspond to a color patch on the target document. All of the selected pixels correspond to the color patch. The pixels of the image have color values associated therewith. A position in the image is determined which is expected to correspond to the color patch on the target document. An approximation is selected of pixels which correspond to the color patch at the determined position in the image. Groups of all pixels for a border of the approximation are successively discarded, thereby reducing an area of the approximation. The groups of pixels are successively discarded until a variance of color values is stabilized for pixels in the approximation.