LSC.zip matlab源码和图片帮助理解

clc clear all; close all; BLOCK_X = 9 BLOCK_Y = 7 img_test = imread('test_rggb.bmp'); img_flat = imread('flat_rggb.bmp'); %原图像 [rown,coln] =size(img_flat); %分通道 r = img_flat(1:2:end,1:2:end); b = img_flat(2:2:end,2:2:end); g = zeros(rown,coln/2); g(1:2:end,:) = img_flat(1:2:end,2:2:end); g(2:2:end,:) = img_flat(2:2:end,1:2:end); %中值滤波，可以抑制噪声的干扰 img_filt= img_flat; % img_filt=medfilt2(img_flat); subSampleRGB=ones(BLOCK_Y+1,BLOCK_X+1,3); strideX=floor(coln/BLOCK_X-1); strideY=floor(rown/BLOCK_Y-1); for i=1:BLOCK_X+1 for j=1:BLOCK_Y+1 rows = floor((j-1-0.5)*strideY); rowe = floor((j-1+0.5)*strideY); cols = floor((i-1-0.5)*strideX); cole = floor((i-1+0.5)*strideX); if rows <= 0 rows=0; end if rowe >= rown; rowe = rown; end if cols <= 0 cols=0; end if cole >= coln; cole = coln; end subimg = zeros(rowe-rows,cole-cols); subimg = img_filt(rows+1:rowe,cols+1:cole); subSampleRGB(j,i,1)=mean2( subimg(1:2:end,1:2:end)); gr=mean2( subimg(1:2:end,2:2:end)); gb=mean2( subimg(2:2:end,1:2:end)); subSampleRGB(j,i,2) = mean2([gr,gb]); subSampleRGB(j,i,3)=mean2( subimg(2:2:end,2:2:end)); end end figure(3) [A,B] = meshgrid(1:BLOCK_X+1,1:BLOCK_Y+1); mesh(A,B,subSampleRGB(:,:,1)); hold on mesh(A,B,subSampleRGB(:,:,2)); hold on mesh(A,B,subSampleRGB(:,:,3)); %Gainlut luma gain (Y-shading gain) gainlut=zeros(BLOCK_Y+1,BLOCK_X+1,3);% gainlut centerX = coln/2; centerY = rown/2; centerXs = centerX - strideX/2 + 1; centerXe = centerXs + strideX - 1; centerYs = centerY - strideY/2 + 1; centerYe = centerYs + strideY - 1; centerimg =img_filt( centerYs:centerYe,centerXs:centerXe); centerRvg = mean2( centerimg(1:2:end,1:2:end)); centerBvg = mean2( centerimg(2:2:end,2:2:end)); centergr=mean2( centerimg(1:2:end,2:2:end)); centergb=mean2( centerimg(2:2:end,1:2:end)); centerGvg = mean2([centergr,centergb]); centerAVG = [centerRvg,centerGvg,centerBvg]; for i = 1:BLOCK_X+1 for j =1:BLOCK_Y+1 for k = 1:3 gainlut(j,i,k)=centerAVG(k)/ subSampleRGB(j,i,k); end end end %Gainlut chroma gain (colorshading gain) gainlut_c = zeros(BLOCK_Y+1,BLOCK_X+1,2); center_RoverG = mean2( subSampleRGB(floor(BLOCK_Y/2+1) : floor(BLOCK_Y/2+1)+1, floor(BLOCK_X/2+1) : floor(BLOCK_X/2+1)+1,1)) / mean2( subSampleRGB(floor(BLOCK_Y/2+1) : floor(BLOCK_Y/2+1)+1, floor(BLOCK_X/2+1) : floor(BLOCK_X/2+1)+1,2)); center_BoverG = mean2( subSampleRGB(floor(BLOCK_Y/2+1) : floor(BLOCK_Y/2+1)+1, floor(BLOCK_X/2+1) : floor(BLOCK_X/2+1)+1,3)) / mean2( subSampleRGB(floor(BLOCK_Y/2+1) : floor(BLOCK_Y/2+1)+1, floor(BLOCK_X/2+1) : floor(BLOCK_X/2+1)+1,2)); for i = 1:BLOCK_X+1 for j =1:BLOCK_Y+1 RoverG = subSampleRGB(j,i,1)/subSampleRGB(j,i,2); BoverG = subSampleRGB(j,i,3)/subSampleRGB(j,i,2); gainlut_c(j,i,1) = RoverG/center_RoverG;%/RoverG-1; gainlut_c(j,i,2) = BoverG/center_BoverG;%/BoverG-1; end end %chroma+luma gain gainlut_full = zeros(BLOCK_Y+1,BLOCK_X+1,2); for i = 1:BLOCK_X+1 for j =1:BLOCK_Y+1 gainlut_full(:,:,1) = gainlut(:,:,1) + gainlut_c(j,i,1); gainlut_full(:,:,2) = gainlut(:,:,2) + gainlut_c(j,i,2); end end %(BLOCK_H+1)*(BLOCK_V+1) colorgain figure(4) [C,D] = meshgrid(1:BLOCK_X+1,1:BLOCK_Y+1); mesh(C,D,gainlut_c(:,:,1)) hold on mesh(C,D,gainlut_c(:,:,2)) %Y shading correction gain figure(5) mesh(C,D,gainlut(:,:,1)) hold on mesh(C,D,gainlut(:,:,2)) hold on mesh(C,D,gainlut(:,:,3)) figure(6) mesh(C,D,gainlut_full(:,:,1)) hold on mesh(C,D,gainlut(:,:,2)) hold on mesh(C,D,gainlut_full(:,:,2)) % gainlut(:,:,1) = gainlut_full(:,:,1); % gainlut(:,:,2) = gainlut(:,:,2); % gainlut(:,:,3) =gainlut_full(:,:,2); %双线性插值FullGainLut x = 1:strideX:coln+1; x(end) = coln; y = 1:strideY:rown+1; y(end) = rown; xitp = 1:2:coln; yitp = 1:2:rown; [Xitp,Yitp]=meshgrid(xitp,yitp); rgain=interp2(x,y,gainlut(:,:,1),Xitp,Yitp); xitp = 2:2:coln; yitp = 1:2:rown; [Xitp,Yitp]=meshgrid(xitp,yitp); grgain=interp2(x,y,gainlut(:,:,2),Xitp,Yitp); xitp = 1:2:coln; yitp = 2:2:rown; [Xitp,Yitp]=meshgrid(xitp,yitp); gbgain=interp2(x,y,gainlut(:,:,2),Xitp,Yitp); xitp = 2:2:coln; yitp = 2:2:rown; [Xitp,Yitp]=meshgrid(xitp,yitp); bgain=interp2(x,y,gainlut(:,:,3),Xitp,Yitp); [gn,gm]=size(gbgain); ggain = zeros(gn*2,gm); ggain(1:2:end,:) = grgain; ggain(2:2:end,:) = gbgain; gain=zeros(rown,coln); gain(1:2:end,1:2:end) = rgain; gain(1:2:end,2:2:end) = grgain; gain(2:2:end,1:2:end) = gbgain; gain(2:2:end,2:2:end) = bgain; lscgain = gain; figure(7) imgDoubleType = im2double(img_flat); imgDoubleType = imgDoubleType.*lscgain; imgUint = im2uint8(imgDoubleType); imshow(imgUint) imwrite(imgUint,'flat.bmp','bmp') figure(9) subplot(2,2,1) [rown,coln] =size(img_flat); width = 1:coln; height = 1:rown; [X1,Y1] = meshgrid(width,height); mesh(X1,Y1,im2double(imgUint)); subplot(2,2,2) width = 1:coln; height = 1:rown; [X1,Y1] = meshgrid(width,height); mesh(X1,Y1,im2double(img_flat)); subplot(2,2,3) width = 1:coln; height = 1:rown; [X1,Y1] = meshgrid(width,height); mesh(X1,Y1,im2double(img_filt)); figure(8) imgDoubleType = im2double(img_test); imgDoubleType = imgDoubleType.*lscgain; imgUint = im2uint8(imgDoubleType); imshow(imgUint) imwrite(imgUint,'test_lsc.bmp','bmp')