Start storing the recorded sound with pressing the button in real time

I record speech from the microphone, I use audiorecorder and a timer function fire every one second and doing some process (as FFT) the plot data captured in that last one second. I want to store FFT samples in a csv file when I push store button and stop storing when I push StopStore button. (for example I push store button in 4th second of recording and I push Stop button in 10th second, I want to save fft for 6 seconds (4s-10s) in csv file).

Could somebody help me how to do that. Thanks

[Geoff Hayes]

hoda - are you saving the samples in a csv file because some other application will be analyzing the data? or can you save this data as a mat file for MATLAB to analyze further?

[hoda kazemzadeh]

Yes somebody will use the data who may not have MATLAB so mat file is not practical. But even in mat file , can I save in that way that I explained? all the solutions that I have tried gave me the file with the samples from the beginning up to the moment that I press the store button. (I want to store from the moment I press store button up to when I press another button lets say stopstore button)

[hoda kazemzadeh]

The same as the fft sample and more important for me is to store recorded audio in wav format when I press store button. I use audiowrite to write corresponding samples in wav format but the same problem as fft samples which I explained already.

[Geoff Hayes]

hoda - I'm not sure how you are storing the data (you may need to post some code) but presumably when the user presses the "store" button you, any data sampled afterwards would be collected until the user presses the stop store button. How are you starting the collection of data?

[hoda kazemzadeh]

 function store_Callback(hObject, ~, handles)
 T=strrep(datestr(now),':','-');
 filename=['record''-',T,'.wav'];
 audiowrite(filename,handles.samples,handles.FS,);

samples are those we got in audiotimer callback:

 handles.samples  = getaudiodata(hObject);

when I press the store button it collects the samples (which are the samples collected from the beginning of recording and not starting from this moment). I tried this:

 audiowrite(fname,handles.samples((handles.atTimSecs*handles.FS):end),handles.FS); % FS is sampling frequency

but I am sure both are wrong, I dont know how to make connection with the stopstore function to say how many samples should be collected:

 samples((handles.atTimSecs*handles.FS):??)

[Walter Roberson]

It would be better to use the Audio System Toolbox if you have that.

Question: the second that the user pushes the stop button, do you want to include to the end of that second, or discard that second?

[hoda kazemzadeh]

I can do both cases,the one which is simpler to do. for the moment I am not able to start storing from the second I push button.

[Geoff Hayes]

hoda - if handles.samples is an array of all collected samples (since starting the audio recorder), then when you press the store button (to start storing the data), just keep track of the number of samples that have been collected so far

 function store_Callback(hObject, ~, handles)
 handles.storeStartIdx = length(handles.samples);
 guidata(hObject, handles);

Then in your stop (storing) button callback, you would create the file

 function stopStore_Callback(hObject, ~, handles)
 T=strrep(datestr(now),':','-');
 filename=['record''-',T,'.wav'];
 audiowrite(filename,handles.samples(handles. storeStartIdx:end),handles.FS,);

Or is handles.samples just the last second of collected data? Please clarify.

[hoda kazemzadeh]

Geoff- Yes the handles.samples is the array of all collected data from the beginning of recording. I try what you proposed and working perfect! I did the same for storing FFT data in the same way and is working well. Thank you very musch.

[Geoff Hayes]

glad that it worked, Hoda!

Answer 1

[Geoff Hayes]

hoda - since handles.samples is an array of all collected samples (since starting the audio recorder), then when you press the store button (to start storing the data), just keep track of the number of samples that have been collected so far

 function store_Callback(hObject, ~, handles)
 handles.storeStartIdx = length(handles.samples);
 guidata(hObject, handles);

Then in your stop (storing) button callback, you would create the file

 function stopStore_Callback(hObject, ~, handles)
 T=strrep(datestr(now),':','-');
 filename=['record''-',T,'.wav'];
 audiowrite(filename,handles.samples(handles. storeStartIdx:end),handles.FS,);