## Statistical analysis wavelet coefficients

Started by in comp.dsp15 years ago

Hi All, I am doing my thesis in audio analysis using Wavelet transform.I want to know that is it possible that after getting wavelet...

Hi All, I am doing my thesis in audio analysis using Wavelet transform.I want to know that is it possible that after getting wavelet coefficients, I can use some statistics to find glitches,pop or distortion in my audio data? I am new in this topic, so If I am thinking in diffrent direction then also please tell me.Basically, I want to test recorded audio from mobile phone for different...

## Wavelet data compression

Started by in comp.dsp15 years ago 3 replies

Hello I am trying to do some data compression using the DWT techniques but i have encoutered some problems. Once i have set the threshold...

Hello I am trying to do some data compression using the DWT techniques but i have encoutered some problems. Once i have set the threshold values, all the DWT coefficients that were less than the chosen value were reduced to zero which was the purpose. But on the other hand i would like to reconstruct the signal using only the remained coefficients without using those coefficients replaced wit...

Started by in comp.dsp15 years ago 2 replies

Hi, I was wondering what book do you people recommend for learning Wavelet analysis. Also I appreciate if you answer the same question...

Hi, I was wondering what book do you people recommend for learning Wavelet analysis. Also I appreciate if you answer the same question for differential equations and their numerical methods of solution. I need them to be easily written and at the same time, profound. I just recently read the book "Understanding Digital Signal Processing" by Rick Lyons and enjoyed it a lot. I appreciate if y...

## help: understanding "DAUB4 Level 3 (22 coefficients)"

Started by in comp.dsp15 years ago

I was recently reading about a wavelet bandpass filter constructed using DAUB4 coefficients, level 3 (22-tap FIR filter). I've briefly skimmed...

I was recently reading about a wavelet bandpass filter constructed using DAUB4 coefficients, level 3 (22-tap FIR filter). I've briefly skimmed the numerical recipes in C chapter on wavelets, and some other sources, but I can't quite find an interpretation of this statement that will help me in obtaining the FIR filter coefficients. Can anyone help me interpret this? I need to implement thi...

## analye time series and signal

Started by in comp.dsp15 years ago

Powerful software tools for data analysis is one major topic in many kinds. Release 6 of the well-established software package Dataplore 2.2 is...

Powerful software tools for data analysis is one major topic in many kinds. Release 6 of the well-established software package Dataplore 2.2 is now available. Besides all standard preprocessing tools, spectral analysis and digital filters Dataplore provides - Time-frequency spectra and analysis tools for non-stationary data - numerous statistics functions, modelling and fitting - Wavelet...

## Wavelet Filter bank and Pseudo-QMF filter bank

Started by in comp.dsp15 years ago

Hi All, I want to design sub-band filtering for audio signal processing, the number of filter banks(Sub-bands) will be decided on the...

Hi All, I want to design sub-band filtering for audio signal processing, the number of filter banks(Sub-bands) will be decided on the fly. Here are my queries reagrding this. 1. In filter bank implementation is FIR filter implementation or IIR fiter implementation is better. 2. Which would be the best method to go either a wavelet transform method or Pseudo-QMF filter bank. ...

## Wavelets with improved frequency

Started by in comp.dsp15 years ago 4 replies

Hi to all!!! I'am Intersted in digital image processing, using wavelets. So, i must get wavelets with improved resolution in frequency. Not H...

Hi to all!!! I'am Intersted in digital image processing, using wavelets. So, i must get wavelets with improved resolution in frequency. Not H - [0;0.5], G - [0.5;1], but may be H - [0;0.4], G - [0.6;1], where H - low pass filter, G - high pass filter. At current time i use wavelt packets and m-band wavelet transform to solve this task. Has anyone some ideas aboit such problem? Ple...

## doubts regarding hilbert transform:

Started by in comp.dsp15 years ago 1 reply

Hi I am currently working on huang hilbert analysis.I have some basic doubts regarding it.Can i know what inferences can be drawn by just looking...

Hi I am currently working on huang hilbert analysis.I have some basic doubts regarding it.Can i know what inferences can be drawn by just looking at the imfs and the corresponding hilbert spectrum.What are the advantages of hilbert over fourier and wavelet other than that it is used for both non linear and non stationary data Thank you

## help: morlet wavelet

Started by in comp.dsp15 years ago 2 replies

Hello, I am wondering if there is any public matlab code for discrete and continuous morlet wavelet transform? Any points will be greatly...

Hello, I am wondering if there is any public matlab code for discrete and continuous morlet wavelet transform? Any points will be greatly appreciated. Best, OR

## Wavelet question!!!

Started by in comp.dsp15 years ago 1 reply

Hello All I am new to to the Wavelet topic and I need to understand some basics My question is that if I use the following Matlab code I = [2...

Hello All I am new to to the Wavelet topic and I need to understand some basics My question is that if I use the following Matlab code I = [2 5 8 9 7 4 -1 1]; [cA,cD] = dwt(I,'db4'); I get the following result for cA and cD cA = 10.5188 10.8384 2.6725 7.6008 12.8422 3.6526 0.8223 cD = 0.3774 0.6048 -0.9413 -1.9202 0.9256 1.8001 -0.1160 The question is: H...

## Wavelet questions?

Started by in comp.dsp15 years ago 3 replies

Dear all, I have three quesitons. 1. DWT subband coding uses both low-pass filter and high-pass filter. Are these two filters QMF filters?...

Dear all, I have three quesitons. 1. DWT subband coding uses both low-pass filter and high-pass filter. Are these two filters QMF filters? Just two filters here, what is the matter with Wavelet? For QMF filter, only cos(a*w) can be perfect reconstruction and linear phase. DWT is perfect reconstruction and FIR is with linear phase. Also DWT should be QMF filters. They are not matching....

## Difference between Wavelet and Filter bank?

Started by in comp.dsp15 years ago 7 replies

Dear all, What is the difference between Wavelet and Filter bank? From my understanding, wavelet is a special case of filter bank. Is...

Dear all, What is the difference between Wavelet and Filter bank? From my understanding, wavelet is a special case of filter bank. Is it correct? One thing I feel confused. Wavelet can be viewed as an impulse response of a filter. Some window functions also have the similiar response. Why bother to introduce a new concept "wavelet"?

## Wavelet Phase Spectra vs. Power Spectra

Started by in comp.dsp15 years ago

I'm using the continous wavelet transform for analysis of a time-series which I know contains activity in two known frequency regions. The...

I'm using the continous wavelet transform for analysis of a time-series which I know contains activity in two known frequency regions. The power spectra, |Ca,b|?, seems to give no indication of what I suspect to find, however the phase spectra, tan??(Im(Ca,b)/Re(Ca,b)), very well shows activity in the correct scales. What is going on? What physical meaning has a phase spectrum? I'm using the compl...

## Wavelet

Started by in comp.dsp15 years ago

Does anyone know how frequency components (A - LL, H-LH, V-HL, D-HH) of 2d discrete wavelet transfrom are placed on frequency plan???

Does anyone know how frequency components (A - LL, H-LH, V-HL, D-HH) of 2d discrete wavelet transfrom are placed on frequency plan???

Started by in comp.dsp15 years ago

Hi, In JPEG 2000, 5/3 wavelet filter is used to divide the band into low- band and high-band. But I found out the 5/3 filter didn't...

Hi, In JPEG 2000, 5/3 wavelet filter is used to divide the band into low- band and high-band. But I found out the 5/3 filter didn't clearly divide the band, i.e. low-band just do deny a little bit high-band. > From this poor division, So how can wavelet be used for multiresolution analysis? Thanks

## Wavelet Packet based Multi-carrier Implementation

Started by in comp.dsp15 years ago

Hi All, I am Madan, a MS student at TU Delft. I am trying to implement a Wavelet packet based OFDM system in Matlab. The idea is to replace...

Hi All, I am Madan, a MS student at TU Delft. I am trying to implement a Wavelet packet based OFDM system in Matlab. The idea is to replace the conventional Fourier bases with wavelet bases and explore the benefits. Indeed there are quite a lot of papers on this subject....but..little by-way of implementation details. And it is in this regard that seek pointers/leads. My implementation...

## Wavelet Packet based Multi-carrier Implementation

Started by in comp.dsp15 years ago

Hi All, I am Madan, a MS student at TU Delft. I am trying to implement a Wavelet packet based OFDM system in Matlab. The idea is to replace...

Hi All, I am Madan, a MS student at TU Delft. I am trying to implement a Wavelet packet based OFDM system in Matlab. The idea is to replace the conventional Fourier bases with wavelet bases and explore the benefits. Indeed there are quite a lot of papers on this subject....but..little by-way of implementation details. And it is in this regard that seek pointers/leads. My implementation...

## Audio pattern matching

Started by in comp.dsp15 years ago

Hi, Introduction: ******************** I have created an application that knows to match a collection wavelet patterns to sampled audio...

Hi, Introduction: ******************** I have created an application that knows to match a collection wavelet patterns to sampled audio data ( hence, search ), This was achieved by extracting the features ( FFT, Mel-Scale & MFCC ) for the template and the searched/sampled content, and then, checking their correlation. The problem: ******************* The correlation algorithm I use c...

## Audio pattern matching

Started by in comp.dsp15 years ago

Hi, Introduction: ******************** I have created an application that knows to match a collection wavelet patterns to sampled audio...

Hi, Introduction: ******************** I have created an application that knows to match a collection wavelet patterns to sampled audio data ( hence, search ), This was achieved by extracting the features ( FFT, Mel-Scale & MFCC ) for the template and the searched/sampled content, and then, checking their correlation. The problem: ******************* The correlation algorithm I use c...

## Audio pattern matching

Started by in comp.dsp15 years ago 7 replies

Hi, Introduction: ******************** I have created an application that knows to match a collection wavelet patterns to sampled audio...

Hi, Introduction: ******************** I have created an application that knows to match a collection wavelet patterns to sampled audio data ( hence, search ), This was achieved by extracting the features ( FFT, Mel-Scale & MFCC ) for the template and the searched/sampled content, and then, checking their correlation. The problem: ******************* The correlation algorithm I use c...