AVERAGING GREEN VALUES FOR GREEN PHOTOSITES IN ELECTRONIC CAMERAS

Apparatus described for processing a digitized image signal obtained from an image sensor having red, green, and blue color photosites aligned in rows and columns that generate at least three separate color values but only one color value for each photosite location. An arrangement is disclosed for averaging existing green values for green photosite locations which includes structure for storing the digitized image signal, defining green classifiers based upon adding the Laplacian second-order values, and the gradient values to define a classsifier, and modifying a measured green pixel based upon adjacent pixel classifiers. The apparatus further includes structure for determining which classifiers represent a pixel neighborhood of slowly changing scene detail, and replacing the measured green values for a green photosite location with an average of surrounding predicted green pixels as a function of the number of classifiers which are below a predetermined value.