Enhancement of chest radiographs with gradient operators

The use of gradient operators for image enhancement has been widely reported in the literature, but they have not been used routinely in the medical arena, particularly in the most common radiographic plain film procedure, chest radiographs. Gradient operators such as Sobel and Roberts operators, not only enhance image edges but also tend to enhance noise. Overall, the Sobel operator was found to be superior to the Roberts operator in edge enhancement. A theoretical explanation for the superior performance of the Sobel operator was developed based on the concept of analyzing the x and y Sobel masks as linear Alters. By applying pill box, Gaussian, or median filtering prior to applying a gradient operator, noise was reduced, but the pill box and Gaussian filters were much more computationally efficient than the median filter with approximately equal effectiveness in noise reduction. © 1988 IEEE

27 citations (Crossref) [2023-10-31] Citation Key Alias: pop00008 tex.type: [object Object]