Design And Implementation Of Laplace Image Enhancement Based On FPGA

Laplacian image enhancement is a spatial second-order differential algorithm that can highlight the details of a fuzzy image and extract information from an image,while it can provide more clear and sharp visual effects.Image filtering is used for filtering out the noise in an image,weakening the impact of noise on subsequent image processing.Image processing and filtering algorithms are low-level processing and they need a large number of parallel computing,so those processes are very suitable for FPGA.This paper first introduces the current situation of FPGA-based image enhancement and related algorithms at home and abroad,and then analyzes the principle of image filtering and enhancement algorithm.Then the matlab simulation of each algorithm is carried out.By comparing the simulation results,this paper analyzes advantages and disadvantages of all algorithms.In this paper,some algorithms are improved and methods suitable for hardware implementation are proposed.We design a median filter algorithm which is more suitable to run on hardware,it can reduce the number of data comparison largely.In order to reduce the influence of noise in the enhancement process,we propose a limited Laplacian enhancement.Compared with the normal Laplacian algorithm of four-neighborhood and eight-neighborhood,the limited Laplacian enhancement does not amplify the noise in the image and protects the original information of the image.In the fifth chapter,the behavioral level simulation of each designed module in this dissertation is carried out,and then the project runs on FPGA regarding the data stored in RAM as source data which proves the correctness of the algorithm and the feasibility of the hardware implementation.Each module is designed and analyzed using a top-down approach,the top of the structure is analyzed firstly and then the design and implementation of the various underlying modules are introduced.The total Image Enhancement and Filtering project consists of peripheral modules and processing modules.The peripheral modules contain storage of cached image which can output in 3×3 window data,control of output and HDMI displaying module.Filtering and enhancement modules mainly process the 3×3 window data.Different processing modules reuse the same peripheral modules,bringing a great convenience.Finally,the shortcomings of the design and further research direction are pointed out,and the suggestions for improvement are given.