A new method for calculating color image gradient with adaptive vector parameters

To our knowledge, it is difficult to directly extend the grayscale image gradient calculation method to color image processing. Hence, we propose the color image gradient calculation method mentioned in the title. Its core consists of: (1) we calculate the color image gradient with the spatial vector derivative in the hue, saturation, value (HSV) color space; (2) e use the ratio difference of the three components of HSV in different types of image and the mean-square error of the color image histogram to determine the sizes of their three vector parameters and obtain a new gradient calculation formula as given in eq. (16). Our new method overcomes the difficulties of the traditional color image gradient calculation methods in obtaining an image's detailed gradient information and the low robustness and poor universality of the existing color image gradient calculation method. The simulation results, given in Figs.6 and 7, and their analysis show preliminarily that our method can obtain rather good gradient color images and more detailed gradients than the traditional image gradient calculation methods, thus being suitable for various types of color image.