Regarding DCT

Hi All,

I am performing Integer DCT on Lena image.
I am using " C "& i am not able to reconstruct the image correctly.
Before applying DCT I am subtracting 128 from all pixels of input image.
After IDCT i am adding 128 to the result image.
I want to compare my results with MATLAB .
Is anybody know how to use dct i.e. dct2 function of MATLAB?
if anyone has the related code in MATLAB please do send to me.
Thanks in Advance.

Regards,
Jyothi.

Had written a simplistic dct implementation some time back in 'C'. May
help.
http://piyushkaul.tripod.com/dct_c.zip. Optimized 2D-DCT implemention
src would also be available on net at many places.

Regarding using dct2. What problem are you having? The syntax is

B = dct2(A);

Can't possible get any simpler? Hope you are not using int8 etc.
types.

Regards
Piyush

On Aug 29, 5:04 pm, "jyothina" <jyothi.adiba...@wipro.com> wrote:
> Hi All,
>
> I am performing Integer DCT on Lena image.
> I am using " C "& i am not able to reconstruct the image correctly.
> Before applying DCT I am subtracting 128 from all pixels of input image.
> After IDCT i am adding 128 to the result image.
> I want to compare my results with MATLAB .
> Is anybody know how to use dct i.e. dct2 function of MATLAB?
> if anyone has the related code in MATLAB please do send to me.
> Thanks in Advance.
>
> Regards,
> Jyothi.