Implementation And Application Of An Improved Canny Algorithm For Image Edge Detection Based On FPGA

Images are an important medium for conveying information quickly and visually.Amongst this information,edge information is of considerable importance.In practical production and life,there is often a need to use edge information.To address the problems of incomplete noise removal,inconspicuous edge detection and low accuracy in the traditional edge detection algorithm,an improved Canny edge detection algorithm is proposed,and the main research work is as follows:In the algorithm design stage,this paper proposes an improved Canny edge detection algorithm on the basis of the traditional edge detection algorithm.Firstly,MATLAB simulation software is used to compare the current classical mainstream edge detection operators and carry out simulations.Through comparison,it is concluded that the edge detection effect of Canny algorithm is better,and the result map produced by Canny edge detection algorithm has accurate edge positioning,richer image details and can adapt to the real-time environment.Then the Canny algorithm is improved and optimised.The innovation of the improved Canny algorithm is mainly reflected in the following three aspects:(1)the use of adaptive median-Gaussian filter is proposed instead of the traditional Gaussian filter to solve the problem that the noise cannot be fully removed;(2)the use of the improved Soble operator to calculate the gradient amplitude and direction in eight directions to improve edge detection accuracy;(3)using the adaptive Otsu algorithm to obtain thresholds for threshold segmentation,solving the limitations of the traditional Canny algorithm of manually setting high and low thresholds.Finally,experimental tests are conducted,and the experimental results show that the improved Canny algorithm is more effective than other classical edge detection algorithms in the paper in terms of edge detection,richer collected edge information and stronger adaptivity.In the hardware system design stage,the image acquisition module,image caching module,image processing module and image display module are designed to implement the improved Canny algorithm edge detection system based on FPGA.First,the image acquisition module is used to acquire image data,configure the OV5640 camera and perform image acquisition so that it outputs pixel data in RGB565 format,then the image processing module is used to obtain the image data processed by the improved Canny algorithm,and then the image data is cached in the image cache module,and finally the edge of the image is displayed in real time through the HDMI display module.