【图像压缩】基于matlab奇异值分解SVD图像压缩【含Matlab源码 3899期】.zip

%clear all; imagefile = 'nature.jpg'; insert = @(a, x, n)cat(2, x(1:n), a, x(n+1:end)); showImages = 0; res = 1; start = 1; step = 5; ending = 300; count =2; plotcount =2; a = 1; xq = 1:res:ending; N=linspace(start,ending,ending/step); C=linspace(start,ending,ending); y=linspace(start,ending,ending/step); z=linspace(start,ending,ending); N = insert(0,N,0); y = insert(100,y,0); figure(500); title(['Image Quality x Singular Values']); [error , compressedimage] = rgbSVD(imagefile,1,0); subplot(2,3,1) ,imshow(uint8(compressedimage)), title([num2str(1) ' singular value used']); sprintf('Stage 1 Complete \n\n') for i = start:step:ending if (mod(a,4) ==0) a=1; if (plotcount+1 <= 6) [error , compressedimage] = rgbSVD(imagefile,i-1,0); subplot(2,3,plotcount) ,imshow(uint8(compressedimage)), title([num2str(i-1) ' singular values used']); plotcount = plotcount +1; end end if mod(i-1,30)==0 % y(count) = rgbSVD('nature.jpg',i,showImages); % if (plotlist) <= 2*5 %newimage = imread('nature.jpg'); %[indexedimage,colorMap] = rgb2ind(uint8(newimage),128); %subplot(2,5,plotlist),imshow(uint8(indexedimage),uint8(colorMap)), title(['Compressed Image with ' num2str(i) ' singular values']) %plotlist = plotlist +1; y(count) = rgbSVD(imagefile,i,showImages); else y(count) = rgbSVD(imagefile,i,0); end count=count+1; a = a+1; end sprintf('Stage 2 Complete \n\n') count =2; for i = 1:res:ending [z(count) , images] = rgbSVD(imagefile,i,0); count = count +1; end sprintf('Stage 3 Complete \n\n') C = insert(0,C,0); subplot(2,3,6) , imshow(imagefile) , title('Original Image'); %z = insert(100,z,0); %xq = insert(0,xq,0); vq = interp1(C,z,xq,'PCHIP'); movegui(500,'west'); figure(ending+1); syms b; l = vpasolve(vq(1)/b==100,b); vq = double(vq/l); plot(xq,vq); title('Error in compression'); grid on xlabel('Number of Singular Values used'); ylabel('Percent Error between compressed and original image'); set(gca,'xtick',[0:25:300]); movegui(ending+1,'east'); p = polyfit(xq,vq,2); legend([num2str(p(1)) 'x^2 + ' num2str(p(2)) 'x + 100']); sprintf('Stage 4 Complete \n\n')