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Problem using LWT2

Started by nirup reddy December 14, 2005
Hi friends,
I am able to do the first level lifting wavelet transform using haar wavelet as shown below

rgb_img = imread('c:/lena512.jpg');
I = .2989*rgb_img(:,:,1)+.5870*rgb_img(:,:,2)+.1140*rgb_img(:,:,3);
lshaar = liftwave('haar');
els = {'p',[-0.125 0.125],0};
lsnew = addlift(lshaar,els);
[cA,cH,cV,cD] = lwt2(I,lsnew)

Please let me know if what i have done is right

I have 3 problems first

I am not abe to use bmp image in the first line which is
rgb_img = imread('c:/lena512.bmp');(i have a seperate bmp image of lena)
why does it say "??? Index exceeds matrix dimensions."

next how do i do higher level decomposition
do i use some thing like this ??
higherdec = lwt2(I,lsnew,2);
if yes then i am not getting the same results as the DWT second level decomposition why? Please let me know how to use "els"
how does it vary with the wavelets where do i use p and d

Thnaking you
Regards
Nirup Kumar Reddy