Spline Wavelet Transform Multiscale Image Edge Detection

Image multiscale edge detection based on spline wavelet transform is mainly studied in the paper. Image segmentation is an important step in digital image analysis, it is also the premise of computer vision and pattern recognition Edge detection technology is a typical method for image segmentation. The wavelet transform has excellent time and frequency feature, which has a progressive application in image edge detection. The present situation and development of digital image processing are represented in chapter 1, and the importance of edge detection is also stated. Three kind of traditional image segmentation , their characters and their appropriate objects are analyzed in chapter 2. The theory of wavelet transform and the fast Mallat algorithm of dyadic discrete wavelet transform are given in chapter 3. The edge detection methods and the spline wavelet concepts are mainly studied in chapter 4. Pre-decomposition algorithm and pre- reconstruction algorithm about spline wavelet function are designed. Using 2- order based spline , 3-order based spline and 4-order based spline, a standard image edges are detected, their results are also compared with the results detected by other three wavelet transform. At last , a traffic number image, which is blurred and added noise, is simulated edge detection using 3-order based spline wavelet under the scale of 2. A conclusion is drawn that the result of spline wavelet transform edge detection is better than the result of Laplacian edge detection obviously.