I. INTRODUCTION
Edge detection is the important precondition of image segmentation, the researchers have proposed a series of gray color edge detection methods and have obtained the very good effect. Color is a powerful descriptor and it plays the important role in the aspect of digital image denotation. The statistic shows that about 90% edge information in the color image is the same as in the gray image, that is to say, about 10% edge information in the color image has not been detected, so it is essential that to research the problem of color image edge detection[1], [2], [3], [4]. So during the last years the researchers have put forward a lot of arithmetic on RGB image edge detection. Its material steps are the three steps are as follows: expanding the edge detection method to the three components of RGB color space, combining the edge of the three components by definite logic algorithm and obtaining the color image edge. The common shortcomings of the RGB image edge detection arithmetic are the low speed and the color losses after the each component processing[4], [5]. So YUV color space that is more according with the color vision characteristic than the other color space can be adopted during the processing of the color image edge detection, the paper proposes the basic steps of YUV image edge detection method and improves it according to histogram equalization.