Answered
reconstruct DWT with detail 2 to detail 5 for 1-D signal
[C,L] = wavedec(x,8,'db8'); Cnew = zeros(size(C)); indices = cumsum(L); Cnew(1:L(1)) = C(1:L(1)); Cnew(indices(4)+1:in...

15 years ago | 0

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Answered
reconstruct DWT with detail 2 to detail 5 for 1-D signal
Hi I'm assuming you want to keep the level 5 scaling (approximation) coefficients. Let x be your signal. You can zero out th...

15 years ago | 0

Answered
converting a specific string to two fractions
One way: inputfrac = '12/345'; loc = find(ismember(inputfrac,'/')==1); num = str2num(inputfrac(1:loc-1)); den = str2num...

15 years ago | 0

Answered
combining RGB to get a full image
Hi, You don't want to concatenate along the column dimension. An RGB image has 3 dimensions. You want to concatenate along the 3...

15 years ago | 0

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Convolution encoder
Not sure what your question is here. Assume you have a encoder with 3 memory registers, 1 input bit, and 3 output bits. To en...

15 years ago | 0

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Answered
wavplay stall
Hi, if you replace your wavplay(x,sr) calls with audioplayer(x,sr) Does that help?

15 years ago | 0

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wavelte packet reconstruction
Hi, It doesn't make sense in a wavelet packet tree to adjust each node separately because the higher levels nodes depend on the ...

15 years ago | 0

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How to convert an array into matrix of different sized cloumns
Hi, you would have to do this as a cell array unless you were content to fill out the "missing" elements in the rows with NaN or...

15 years ago | 0

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Fourier transform- a general question
Hi, you are correct. When you are referring to the noise parts of a speech waveform, you are most likely talking about sounds li...

15 years ago | 0

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wavelte packet reconstruction
Hi, You can use wpthcoef or wpdencmp for denoising. Or you can simply modify the terminal nodes of your original tree, then crea...

15 years ago | 0

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Question about using quad function
You need a ./ in your division. For example: x = 1:.01:4; quad(@(x) (5+log(x))./(x.^2+1),1,4)

15 years ago | 0

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Sum of sines fitting algorithm: What is happening to the phase value?
Hi, the basic least-squares estimates work fine here: time=[2007.1 2007.2 2007.3 2007.4 2007....

15 years ago | 0

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Answered
what is function of [ ] in this code
It says "use the default value for the input N, the number of frequency points". in freqz() that is 512. So [H,F] = freqz(...

15 years ago | 0

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Answered
how to get dct co-efficients of a compressed image
Please read the documentation for dct2 >>doc dct2

15 years ago | 0

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Answered
IF statements with zero
Hi Lisa, a = [ 0 0 1 1 0 0 ]; b = [ 19 19 19 19 19 19]; for n = 1:6 if (a(n) <=0.5) ...

15 years ago | 0

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Answered
use of eval
plots=[3 4 6 1]; whatplot = 'bar'; eval([whatplot '(plots)'])

15 years ago | 0

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use of eval
Your call to input() returns the string bar in whatplot but whatplot(plots) is not a string. eval([whatplot '(plots)...

15 years ago | 0

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Answered
Subtraction of Two sequences
Hi, please format your code for readability in future posts. Save the function subseq1.m in a folder on the MATLAB path and t...

15 years ago | 0

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Hold on not working with ezplot3
Hi Sara, ezplot3() is written in such a way that it undoes the effect of any previously issued hold on command. In this case...

15 years ago | 0

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Answered
Is the unit of Cxy from cpsd in decibel?
Hi, no, the output is the cross spectrum, it is complex-valued. If you want the output in db. Use 10*log10(abs(Pxy)); For ex...

15 years ago | 0

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Answered
How to properly use the ifft function ?
x = randn(1000,1); xdft = fft(x); y = ifft(xdft,'symmetric'); max(abs(x-y)) The 'symmetric' option enforces that t...

15 years ago | 0

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1)Amplitude modulation. 2) Negative amplitudes in the signal??
The Fourier transform of any real-valued signal is conjugate symmetric, in other words, the Fourier transform at -f is the compl...

15 years ago | 0

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Answered
1)Amplitude modulation. 2) Negative amplitudes in the signal??
Just like what you see in a cosine or sine, as the phase changes through a cycle of 2*pi radians, those functions have equal pos...

15 years ago | 0

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1)Amplitude modulation. 2) Negative amplitudes in the signal??
Hi, It is very common for any signal to have negative and positive amplitudes, particularly for signals that oscillate. If you t...

15 years ago | 0

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Signal filtering
You have to know your sampling rate in order to know how many samples a 25-ms frame is. Here I'll assume it's 10 kHz. So 250 sam...

15 years ago | 0

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how to read .mp4 videos in matlab
On Windows 7, you can use VideoReader to read a .mp4 file. See the help for an example of reading one frame at a time. If ...

15 years ago | 0

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Answered
error in command awgn
There is a file named awgn.m in this directory C:\Users\Admin\Documents\MATLAB that precedes MATLAB's awgn.m function on your ...

15 years ago | 0

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Answered
Syntax error of old version ???
[~, board_idx] = min(SCORE); The above syntax where you can suppress an output argument was not included the R2007b version...

15 years ago | 1

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Answered
Need help for DTMF Scoring fucntion
I wouldn't write it like this because the dtmfscor function needs to know which column of tones it needs. But if you call the fo...

15 years ago | 0

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Answered
Need help for DTMF Scoring fucntion
Hi Moonman, here is a modification that outputs only one tone: function tone = dtmfseg(symb) symbol = {'1','2','3','...

15 years ago | 0