METHOD FOR AUTOMATIC DETECTION AND CORRECTION OF HALO ARTIFACTS IN IMAGES

A method of automatically detecting and correcting halo artifacts within a processed image is described. The method computes a two-dimensional (2D) gradient field of the original image and a 2D gradient field of the processed image. Each gradient field includes a gradient vector corresponding to each pixel. To detect halo artifacts, the gradient vector at each pixel of the original image is compared to the gradient vector at the corresponding pixel of the processed image. A halo artifact is determined to exist at a given pixel if a direction of the two corresponding gradient vectors differs by at least a specified threshold. To correct the halo artifacts, a composite gradient field is generated using one of three correction methods. A final image is generated by integrating the newly generated composite gradient field using known integration methods from a 2D gradient field such as ones based on the Fast Fourier Transform.