Reduced size images may be generated by separating dimensions that span the original image into a plurality of groups so that data in each group of one or more dimensions may be processed differently from data of other groups. For example, for two-dimensional images, pixels of selected lines may be completely discarded or skipped while pixels of remaining lines may be processed along the x-dimension to obtain data of the reduced size image. The main advantages include very fast and efficient implementation, minimal storage requirements, and good image quality.