Hi I am working on EZW coding. The first part that is subband decomposion is done in MATLAB. Now I have an array of wavelet...

Hi I am working on EZW coding. The first part that is subband decomposion is done in MATLAB. Now I have an array of wavelet coefficients with size 256 -by- 256. I need to store this array in a file with only 8 bits/coefficient in the signed char format. The r

I would like to ask the people who have experiences in wavelets. I am doing frame by frame wavelet packet decomposition , im...

I would like to ask the people who have experiences in wavelets. I am doing frame by frame wavelet packet decomposition , im just wondering whether overlap windowing should be done like that in taking frame by frame fourier transform ( does it apply to fram by frame wav

How to present time-frequency distribution using wavelet transformation or reassigned Gabor transformation? Many Thanks. ...

How to present time-frequency distribution using wavelet transformation or reassigned Gabor transformation? Many Thanks.

Hi everyone, i did short time fourier transform(STFT) on 1-D speech signals, and did spectrogram analysis. On one paper I found that it is...

Hi everyone, i did short time fourier transform(STFT) on 1-D speech signals, and did spectrogram analysis. On one paper I found that it is possible to come up with a wavelet based analogy of spectrograms, it was called "scalogram" at that paper. So, I set about trying to figure out a way to come up with scalogram code in matlab. After coding a matlab program which does a full decomposition...

Dear All Does anyone know how to convert a .MAT file into an image file The basic problem is that I am using the wavelet toolbox...

Dear All Does anyone know how to convert a .MAT file into an image file The basic problem is that I am using the wavelet toolbox which saves the image compression results in a Mat file so I need to convert it into some standard form to see the result another does anyone

Hi all, I work with MATLAB R11 on image compression by wavelets. I need compress ratio about 150 to 1 but MATLAB has worse result...

Hi all, I work with MATLAB R11 on image compression by wavelets. I need compress ratio about 150 to 1 but MATLAB has worse result after compresion as commercial product (LuraTech). I need compress image 176x176 to 256 numbers (char) but I don't know which coeficient I must save. I ca

Has anyone worked with wavelets based OFDm. I would like to know how one included the idwt and dwt fucntion for an OFDM code. --...

Has anyone worked with wavelets based OFDm. I would like to know how one included the idwt and dwt fucntion for an OFDM code. -- Regards Oswald Jumira Communications Research Group Room 5.26 Menzies Building Department of Electrical Engineering University of Cape Town P Bag X5 Rondebosch 7701 Tel: +27216504879 Cel: +27720308211 Email: o...@uct.ac.za o...@ieee.org "To raise new...

This MATLAB program is for making a suitable wavelet kernel It derives the Low pass filter by sampling from analog raised cosine function in...

This MATLAB program is for making a suitable wavelet kernel It derives the Low pass filter by sampling from analog raised cosine function in frequency domain and taking ifft from this function to yield the impulse response. (other filters are derived using orthogonal relations). first i wnat know if the filter design method has any problems? The filter has 2 parameters in frequency domain ...

i want to capture my voice in matlab .and then i want to sample it at 16000 samples/sec.then i want to take its FFT and...

i want to capture my voice in matlab .and then i want to sample it at 16000 samples/sec.then i want to take its FFT and wavelet transform.plz i want immediate help salman

Hi all, I have a doubt in constructing a tree vector. I have a signal for which i took wavelet transform.i have got the...

Hi all, I have a doubt in constructing a tree vector. I have a signal for which i took wavelet transform.i have got the approximation and detail coefficients ,how will i construct a tree vector for these coefficients.I have decomposed the signal to five levels.can anyone please help m

Hi, I am doing a project on audio watermarking using Matlab. I am facing the following problem. I took a small subset of the samples of a...

Hi, I am doing a project on audio watermarking using Matlab. I am facing the following problem. I took a small subset of the samples of a .wav file. I embedded a small bitmap in the LSBs of the wavelet coefficients of this small set of samples and recreated a new .wav file. I wrote the file with the wavwrite function. As the next step, in order to detect the watermark, I read the wa...

I intend to analyze a non-stationary audio signal for its spectral content after splitting it up by several narrow frequency...

I intend to analyze a non-stationary audio signal for its spectral content after splitting it up by several narrow frequency bands (sub-bands). Splitting is performed by wavelet decomposition at required level, then I thought of running an STFT (specgram with narrow window) within each band to figure its spectrum content. Since the bands are quite narrow (several hundreds of herz each) ther...

Hello, I have a question regarding the wavelet decomposition and reconstruction using the functions wavedec and waverec. I get an error during...

Hello, I have a question regarding the wavelet decomposition and reconstruction using the functions wavedec and waverec. I get an error during the reconstruction process when I set the dwtmode option to 'per'. The code I use is as follows: ----------------------------------- dwtmode('per') x = random('unif', 0, 1, 512, 1); [y, L] = wavedec(x, 9, 'db2'); x_rec = waverec(y, L, 'db2'); ---...

hi my dear freinds around the world, i wanted to transform(dwt) an image(barbara)and inverse it.it is my first time i have worked with dwt.these...

hi my dear freinds around the world, i wanted to transform(dwt) an image(barbara)and inverse it.it is my first time i have worked with dwt.these are my codes: X=((imread('barbara.bmp'))); [cA,cH,cV,cD] = dwt2(X,'haar'); Y = idwt2(cA,cH,cV,cD,'haar'); figure,imshow(Y) but the resulting image isn`t like the first image . what `s wrong with my codes? thanks in advance.

I m working on the project "wavelet based watermarking". am using the dwt2 function to get the approximation parameter. while doing so.. Iam...

I m working on the project "wavelet based watermarking". am using the dwt2 function to get the approximation parameter. while doing so.. Iam losing the color of the watermarked image. plzz help me out in obtaining the color component Here is my code.. a=imread('H:\pics\earth_from_space.jpg'); %i=imread('earth_from_space.jpg'); %i=uigetfile( '*.*' , 'select the image'); %[filename1,pat...