myidct_good.m

该压缩包实现二维的DCT变换和逆DCT变换

function x_idct=myidct_good(X)
%确定矩阵大小
[N,N]=size(X);
%求T矩阵
Tpq=zeros(N,N);
Tpq(1,:)=1/sqrt(N);
p=1:N-1;
q=0:N-1;
Tpq(p+1,q+1)=sqrt(2/N)*cos(p'*(2*q+1)*pi/(2*N));

%由T'*X*T得到DCT反变换的结果
x_idct=Tpq'*X*Tpq;