Consider the
result obtained after DCT. (Check 2d-DCT )

Apply
Inverse Discrete Cosine Transform to obtain the original Image.

**MATLAB CODE:**
%2-D INVERSE DISCRETE
COSINE TRANSFORM

%PREALLOCATE THE MATRIX

A=zeros(size(B));

Temp=zeros(size(B));

[M N]=size(B);

x=1:M;

x=repmat(x',1,N);

y=repmat(1:N,M,1);

figure,

imshow(log(abs(B)),[]);colormap(jet);title('After DCT');

for i=1:M

for j = 1: N

if(i==1)

AlphaP=sqrt(1/M);

else

AlphaP=sqrt(2/M);

end

if(j==1)

AlphaQ=sqrt(1/N);

else

AlphaQ=sqrt(2/N);

end

cs1=cos((pi*(2*x-1)*(i-1))/(2*M));

cs2=cos((pi*(2*y-1)*(j-1))/(2*N));

Temp=B.*cs1.*cs2*AlphaP*AlphaQ;

A(i,j)=sum(sum(Temp));

end

end

%OUTPUT

figure,

imshow(abs(A),[0 255]);title('Image after
IDCT');

## 1 comments:

Hi, but this significantly differs from the Matlab IDCT function. Any reason why? Thanks

## Enjoyed Reading? Share Your Views