The Research On Digital Image Enhancement Algorithm Based On NSST And Fuzzy Contrast

Now,the rapid development of imaging technology makes image acquisition more and more convenient.However,due to the influence of various interferences during the process of image acquisition and transmission,problems have arisen,such as reduce of contrast and sharpness and lack of details,which have made it difficult to process and apply of image.The main purpose of image enhancement is to highlight the characteristic of target information,minimize the noises,improve the sharpness of detail information,and make it more conducive to the subsequent analysis and application of image.The main content of this paper is to verify the proposed algorithm by using remote sensing images and medical image as research objects.1.For remote sensing images,due to various interferences during acquisition and transmission of image,many problems have arisen,such as loss of details,reduce of sharpness.This paper proposed a remote sensing image enhancement algorithm combining NSST and fuzzy contrast.Firstly,the original image was decomposed into low frequency component and high frequency component by NSST;Then the low frequency component adopted line stretch to improve the overall contrast,the noises in the high frequency component were removed by the threshold method to eliminate its influence on the image details;And then the reconstruct image was reconstructed by applying the inverse NSST to the processed low-frequency and high-frequency components;Finally,fuzzy contrast was used on reconstructed image to improve the layering of the image and highlight the detailed information.The experimental results show that compared with the traditional algorithms,the algorithm not only obtains clear visual effects,but also improves the contrast and denoising effect.2.Medical images have been increasingly used in modern medical diagnostic system at present.However,because of the medical image is affected by various disturbances during imaging,it ultimately affects the doctor's prediction of the condition.Therefore,this paper proposed a medical image enhancement algorithm based on NSST and fuzzy contrast.Firstly,the original image used adaptively histogram-equalized to enhance the overall contrast of the image;Then the obtained image was decomposed into high-frequency component and low-frequency component by NSST;And the high-frequency components were enhanced by threshold method to remove noise,the line stretch method enhanced the low frequency component to improve the contrast;And then the reconstruct image was reconstructed by applying the inverse NSST to the processed low-frequency and high-frequency components;Finally,the reconstructed image was processed by using the fuzzy contrast algorithm to improve image detail and texture information,and obtain the finally enhanced image.The experimental results show that the proposed algorithm not only obtains better visual effects,but also has obvious advantages in peak signal-to-noise ratio(PSNR),root mean square error(Rmse)and time.