Color Image Edge Detection Based On Mathematical Morphology

Edge detection is the foundation of feature description , image segmentation,image enhancement,pattern recognition and image compression and so on . Also edge detection is a hot topic in digital image processing. Mathematical morphology is a method of image analysis and processing based on the non-linear theory, and widely applied in image processing and pattern recognition. Previous study of morphological processing are mainly restricted to binary morphology and grayscale morphology, although the research of the grayscale morphology extended to color image processing has accumulated a certain amount of results, but the application of morphology in the color image processing is still at an exploratory study phase.At first, the traditional and emerging theories and methods of edge detection are introduced in this paper. Their respective advantages and disadvantages are analyzed, and some typical methods are simulated and compared. Then study of image processing using morphology theory is carried out. The characters of the dilation, erosion, opening operation and closing operation in mathematical morphology based on binary-morphology and gray-morphology are discussed combining with experiments. The morphological gradient method chosen in the paper is verified by simulating.Secondly, for different color space has its own advantages, disadvantages and limitations. Considering the different application environments, in this paper mathematical morphology will be introduced to color image processing combined with different color vector sequences in the RGB color space and the HSL color space, respectively. In the RGB color space, judgment the noise points is introduced to color morphological basic operators by analyzing the characteristics of the noises contaminating color image. The color morphological operators which are insensitive to noise are proposed. New color morphological edge detection algorithm is realized, whereas, in the HSL space new methods of realizing edge detection for color image are constructed based on the gradient algorithm of multi-structuring elements morphological. The improved method of realizing edge detection is proposed based on multi-structuring elements color morphological, and comparative analysis of signal to noise ratio has been made.At last, the capability in many aspects and the problem of the algorithms is summarized.Many experiences are accumulated for further research.