Objective characterization of image acutance
Salaheddin G. Elkadiki, Rangaraj Mandayam Rangayyan · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1994
Acutance refers to the sharpness and thus the perceptibility of features in an image. Currently available methods for characterization of perceptibility of image features are either highly subjective or statistical. There is a need for a purely objective measure to characterize the perceptibility of image features. This paper proposes a measure of acutance based on gray-level variations across the boundary of an object. An algorithm to calculate the acutance based on region growing and a derivative measure across region boundaries has been designed and implemented. After testing the algorithm on various images, it is shown that this measure can accurately reflect changes in the appearance of objects due to blurring and sharpening. Using this technique, it is possible to quantify the level of enhancement in a digital image by calculating the acutance before and after the enhancement operation.