ex_08_09_3.m

其中

% ex_08_09_3.m;   习题 8.9

clear all;clc;
I=imread('girl.bmp');
subplot(221);imshow(I);
%
A=double(I);
B=zeros(size(A));
C=zeros(size(A));
W=[16 11 10 16 24 40 51 61
12 12 14 19 26 58 60 55
14 13 16 24 40 57 69 56
14 17 22 29 51 87 80 62
18 22 37 56 68 109 103 77
24 35 55 64 81 104 113 92
49 64 78 87 103 121 120 101
72 92 95 98 112 100 103 99];
s=size(A);
for m=1:s(1)
    if rem(m,8)==0
        for n=1:s(2)
            if rem(n,8)==0
                B(m-8+1:m,n-8+1:n)=dct2(A(m-8+1:m,n-8+1:n));
                for i=1:8
                    for j=1:8
                        B(m-8+i,n-8+j)=round(B(m-8+i,n-8+j)/W(i,j));
                        if (B(m-8+i,n-8+j)==0)
                        end
                    end
                end
            end
        end
    end
end
for m=1:s(1)
    if rem(m,8)==0
        for n=1:s(2)
            if rem(n,8)==0
                for i=1:8
                    for j=1:8
                        B(m-8+i,n-8+j)=round(B(m-8+i,n-8+j)*W(i,j));
                    end
                end
                C(m-8+1:m,n-8+1:n)=idct2(B(m-8+1:m,n-8+1:n));
            end
        end
    end
end
C=uint8(C);
subplot(222);
imshow(C);
%axis square;xlabel('量化后重建图像');