matlab help , Digital signal processing

Dave

Joined Nov 17, 2003
6,970
That depends on how your image is formatted - do you know what format the image is in, or is it just a continuous array of data? If so, your image should have a corresponding header file which will tell you the physical properties of the image or if you have access to the array as the native formatted array for Matlab (i.e. can be loaded into the workspace), just use the size function.

Dave
 

Thread Starter

dina

Joined Nov 12, 2006
19
hi...
i need to work on binary images but i couldn't find any ...
can anyone provide me a link to some binary images(black and white)
thx
 

Thread Starter

dina

Joined Nov 12, 2006
19
hi again
i tried for a while to find audio Stirmark or checkmark ...
if any one can provide a link to where i can download either i'd appreciate it
 

Dave

Joined Nov 17, 2003
6,970
hi again....
i need any functions in matlab that perform Audio attacks
Thanks for any help
Audio attacks - am I correct in thinking this is some form of spike or impulse on the audio sample? Although not directly related to audio attacks you may be interested in looking at this site about Audio Envelopes, which is closely alligned to audio attacks. There are some m-file you could look at that may be of use.

As a general point for your project, you may be interested in the following paper about Audio Watermaeking using Pychoacoustoc Watermark Filtering: http://www.mediateam.oulu.fi/publications/pdf/93.pdf

Dave
 

sananibha

Joined Feb 26, 2007
1
hi
iam doing my final year graduation project on audio watermarking using fft.
i have completed code in java for text encryption and hiding it in .wav audio file.now iam in need of matlab codes for preprocessing the audio file (ie:fft , filtering and converting the result to .wav file).

Thanks in advance.
 

Thread Starter

dina

Joined Nov 12, 2006
19
hi
am working now on creating an interface on matlab...
i know how to create a button but don't know how to assign a function so that it's executed whenever the button is pushed...
i'd appreciate any help....
 

Dave

Joined Nov 17, 2003
6,970
hi
am working now on creating an interface on matlab...
i know how to create a button but don't know how to assign a function so that it's executed whenever the button is pushed...
i'd appreciate any help....
Just place your code in the button1_Callback(hObject, eventdata, handles) function, where button1 is your button.

I have a challenge for you: Are you using multiple UI windows (i.e. several UI windows each which have their own m-file and fig-file)? If so, try and find out how you transition between each window whilst retaining the window frame.

Dave
 

Thread Starter

dina

Joined Nov 12, 2006
19
hi Dave
well, ur challenge seems interesting especially for a beginner....
i have not designed the GUI yet...am still reading and learninng about GUI in matlab...
i have a question ... if my .m file modified an audio signal and i wanted to plot it on the axes...how is that done?
(is this what u meant?)
 

Thread Starter

dina

Joined Nov 12, 2006
19
Hi
assume the push button performs : [a1,d1] = dwt(signal,'db1');
and i want to plot d1 on the axes of the GUI ... how is that done??
also if we have a list box in the GUI, how do we add the a1,d1 to the list???
 

Dave

Joined Nov 17, 2003
6,970
hi
if anyone at least can provide a sample code for a gui that includes a list box
i'll be grateful
Hi dina,

I wouldn't know how to go about using a list box in a gui. Couldn't you just use the listdlg function to create a list dialog pop-up that you can interact with then interrogate for the answer via your GUI (variables s indicates the selection and v indicates the button select status) - IMO this is simpler approach.

Dave
 
hello , all.

in my class, i should extract the pitch from the wav files, my teacher told me Mathlab can do that.

But i am the beginner for it, i know how to open the wav file, but i don't know how to extract the pitch value at every samples of the wav files.

suppose, a song is 3 mins long,
then i want to extact the pitch value at every sample.

So please help me about this, Thanks.
 

uthung

Joined Jul 7, 2007
1
No problem any further problems let us know. I also got your PM.

Dave
hi guys. could you show me how to generate a PN sequence using linear feedback shift registers in Matlab to create a key. this key is an author's secret key (e.g: 13245768).I'm working on audio watermarking with a wave sound format file and I wanna embed this key into audio signal. And one more, could you explain me this: K= lfsr(key,FFTlength).
FFTlength = 512, key is given above. audio signal is segmented into frames (512 samples each)
 

decloop

Joined May 15, 2008
4
Hi,
My project is entering "Mel" or "Bark" scale in wavelet speech enhancement.
any one can help me to enter this scale in matlab mfile.
I use wavread to read wav file.
then I use DWT function.
But I don't know how to change frequency scale in FFT function
or wavelet function (DWT)!!!

please help me.
 

hasna

Joined Jun 6, 2008
1
hi........im a new1 2 this site.im doin my final yr project in audio watermarking...........pls can u sen me d links where i can get details about watermarking and what is the best algorithm to implemen it

what is the language i can use?

plz frnds i neer ur help
 
Top