reading the sound files as they are being recorded

Hi,

I have a program that calculates the angle of a arrival of a stationary sound source. Now, I want to find the angle of arrival of a moving sound source. For this I need to read my .wav files readily as the sound source speaks and calculate the time delay between the mics, could someone please tell me how to read the sound files readily into matlab program as they are being spoken.

Thanks in advance, padma

Answer 1

[Walter Roberson]

This would be difficult and probably not work right. WAV files include some data compression, so samples are buffered until it is determined that it is time to write the representation of them.

You would be better off reading from the microphone instead of from the .wav files, writing the samples to a file in binary, and also processing the samples, and then as an after-pass, read the binary back in and write it as a .wav

[Padma]

how do you read from the microphone? could you please provide me some info.

[Padma]

can I compute the delay of the sound signal while it is being recorded by the mic? (I mean is there a way I could get it done simultaneouly?)

[Walter Roberson]

http://www.mathworks.com/help/techdoc/ref/audiorecorder.html

which you can use in non-blocking mode. It is not the recommended method, though: recommended is the Data Acquisition Toolkit, such as described http://www.mathworks.com/products/demos/daq/acquiring_data/acquiring_data.html

Your best bet, when timing information is important, is to use an A/D card that has a built-in facility to record sample time-stamps and include them with the returned data. Relying on system timing is *not* advisable, especially not in MS Windows.

[Padma]

thank you, i'll get back to you if I have any doubts.