Image superresolution through edge extraction and contrast enhancement

A computer-readable storage medium having computer-executable instructions stored thereon for generating a high-resolution bitmap from a low-resolution bitmap, said computer-executable instructions comprising:

• magnifying a low-resolution image to form a magnified image;
• performing edge detection on the magnified image to produce an edge map;
• generating a plurality of image patches of the magnified image;
• performing connected components analysis on each of the plurality of image patches and the edge map, to produce a plurality of foreground/background decisions;
• enhancing the contrast of one or more pixels in each of the plurality of image patches, said enhancing depending on the foreground/background decisions, wherein the computer-executable instruction for enhancing the contrast of one or more pixels comprises:
• inputting an image patch;
• computing foreground and background regions based on the foreground and background decisions;
• computing an alpha value based on the mean luminance of the background and foreground region;
• finding the most representative pixel for the foreground and background regions;
• and
• computing the enhanced output pixel luminance from the input pixel luminance using the most representative pixel for the luminance of the foreground or background region and the alpha value;
• and
• producing a high-resolution bitmap from the contrast-enhanced pixels.

A system for generating an enhanced image, comprising:

• a general purpose computing device;
• a computer program encoded on a computer-readable medium comprising program modules executable by the general purpose computing device, wherein the computing device is directed by the program modules of the computer program to, perform edge detection on an image to produce an edge map;
• generate a plurality of image patches of the image using a plurality of windows applied to the image;
• perform connected components analysis on each of the plurality of image patches of the image to find all pixels that are connected to the center pixel of the image patch whose path of connection does not cross an edge pixel, wherein the program module to perform connected components analysis further comprises a sub-module to:
• determine foreground and background regions of each image patch;
• and
• compute a blending factor based on the mean luminances of the foreground and the background regions;
• enhance the contrast of one or more pixels in each of the plurality of image patches, said enhancing depending on the results of connected components analysis;
• and
• produce an enhanced image from the contrast-enhanced pixels.