jpeg.m

来自「原创：用matlab仿真bch算法」· M 代码 · 共 68 行

clear
I=imread('bahuan.jpg');
I=rgb2gray(I);
I=im2double(I);
T=dctmtx(8);
B1=blkproc(I,[8 8],'P1*x*P2',T,T');
B1=B1/0.01;
B1=round(B1);
B1=B1*0.01;
I1=blkproc(B1,[8 8],'P1*x*P2',T',T);

B3=blkproc(I,[8 8],'P1*x*P2',T,T');
mask=[1 1 1 1 1 0 0 0
      1 1 1 1 1 0 0 0
      1 1 1 1 1 0 0 0
      1 1 1 1 1 0 0 0
      1 1 1 1 1 0 0 0
      0 0 0 0 0 0 0 0
      0 0 0 0 0 0 0 0
      0 0 0 0 0 0 0 0];
  B3=blkproc(B3,[8 8],'P1.*x',mask);
  B3=B3./0.1;
  B3=round(B3);
  B3=B3*0.1;
  I3=blkproc(B3,[8 8],'P1*x*P2',T',T);
  
  figure(1);
  imshow(I1);
  title('VBS=8');
  
  figure(3);
  imshow(I3);
  title('VBS=5');
  %************************************************************
  clear;
  I=imread('bahuan.jpg');
  I=rgb2gray(I);
  I=im2double(I);
  T=dctmtx(8);
  B=blkproc(I,[8 8],'P1*x*P2',T,T');
  %B=blkproc(I,[8 8],'DCT2(x)');
  
  B1=B*1000/25;
  B1=round(B1);
  B1=B1*25/1000;
  I1=blkproc(B1,[8 8],'P1*x*P2',T',T);
  
  B2=B*1000/50;
  B2=round(B2);
  B2=B2*50/1000;
  I2=blkproc(B2,[8 8],'P1*x*P2',T',T);
  
  B3=B*1000/75;
  B3=round(B3);
  B3=B3/1000*75;
  I3=blkproc(B3,[8 8],'P1*x*P2',T',T);
  
  figure(1);
  imshow(I1);
  title('QL=25');
  
  figure(2)
  imshow(I2);
  title('QL=50');
  
  figure(3)
  imshow(I3);
  title('QL=75');