Image smoothing with minimal distortion
Steven C. Gustafson, Vasiliki E. Nikolaou, Farid Ahmed · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1995
An innovative method that enhances detail in digital images by smoothing image pixels while introducing minimal distortion is described and tested. In particular, a 14 by 14 pixel region of a diital image is smoothed using a constrained Gaussian radial basis function method. This method centers on each pixel a Gaussian distribution of amplitude such that the sum of all distributions correctly reproduces the gray level of each pixel. To assess the method, the distortion of the smoothed image is measured by the deviation of its power spectrum, from that of the unsmoothed image, determined as a function of the Gaussian distribution width, and comparisons are made with bilinear interpolation, a conventional convolution smoothing technique. The new method is capable of removing more 'pixel noise' while introducing less image distortion, thus permitting the detection and examination of otherwise hidden detail in digital images. Examples include the detection and assessment of enemy weapons in military images and cancerous tumor medical images.