The Research On The Methods Of Image Edge Detection Based On Wavelet Transform Approach

According to Marr's theory on computer vision, image edge detection occupies an important position in computer vision research. Research on the typical problem in computer vision, however, is very difficult because of the complexity of the problem and limitation of the available technique. Wavelet transform analysis is a breakthrough in mathematical tools and methods in recent ten years, its prominent ability for time-frequency analysis brings new chances to solve problems in computer vision. However, the theory of wavelet is not so mature since it was very short since wavelet was put forward, and there are lack of effective methods and rules to conduct wavelet applications, so applications of wavelets are much more difficult than applications of Fourier transform. Under this situation, we try to apply wavelets to image edge detection which is the important module in computer vision. Properties of wavelet are studied carefully with respect to the requirements, and then proper mother wavelet and proper wavelet transform formula are selected, and at last new ideals and new methods for the problem are given.The main important work of this paper:1. Deeply studyed wavelet analysis theory and image detection technology.2. According to the criterion of edge detection and consulting the design-aim of optimal edge-filter, we come out with the best edge detection wavelet—Quadratic B-Spline wavelet. The paper presented a new local adaptive threthold way and an adaptive threshold edge detection for image based on Quadratic B-Spline wavelet transform was presented then.3. This paper realized the non-separated wavelet transform using the lifting scheme and then presented a new method of the image edge detection using the lifting non-separate wavelet based on the quincunx lattice. And the superiority of the new method was proved by the results in the experiment compared with the tradional way.4. A new method of the image edge detection was proposed based on the steerable wavelet multi-resolution principle. We designed the two-dimention directional derivative wavelet filters and achieved the multi-directional derivative feature which the new method was based on. Compared with the Canny method and the classical edge detection way using B-spline wavelet, the efficiency and superiority of the new method was proved by the results in the simulated experiment.We used MATLAB as the simulation platform to verify the research mentioned above...