Mono and stereo sound systems

Hi, Is there a MATLAB code that differentiate between mono and stereo sound channels? I mean, for example, in a GSM call conversation between two speakers can we detect when the left channel (speaker 1) is running and when the right channel (speaker 2) is running? thanks in advance.

[Shadi Ayyad]

In fact, I am searching precisely for a left/right channel detection, i.e., detect which sound channel is currently in progress. I'm not trying to distinguish between stereo and mono, i am trying to distinguish between stereo and dual-mono ("fake" stereo).

In a "real" stereo clip, the left and right channels will both contain data, but they will be different.

In a "fake" Stereo - where its Dual-Mono - Both channels still have audio, except they are identical.

Answer 1

[Walter Roberson]

Why not just take a sampling of the channels and compare? Or compare with tolerance?

N = 512;  %for example
d = Samples(1:N,1) - Samples(1:N,2);
if ~any(d)
   %data is completely identical, bit-for-bit
end
if all(abs(d) < 1/10000)
   %data is nearly identical, a bit of noise maybe
end

Trickier would be if one channel is a delayed version of the other. But at that point do you care? More important would be to determine the extent to which sounds are echoing for echo cancellation purposes; there is demo code for that.

[Shadi Ayyad]

I have an idea and I am trying to apply it in a speaker recognition system project. how can I modify the project? and in which (.m) file should I change in order to apply my idea?

The idea is that, I want to extract features from .wav file containing two speakers talking with each others, but each speaker occupies a single sound channel, i.e., speaker A talks in left channel and speaker B,while responding to speaker A, talks in right channel. I want to find a way that extract the features for the two speakers in this .wav file.

Note: the speaker recognition system project is done by "raghu ram". It is available in File Exchange.

[Walter Roberson]

What would be the difference compared to splitting the stereo file up into two mono files and running the code on each of those two files?

[Shadi Ayyad]

the difference is that I need flexibility and easiness in my code, it is a bit noisy and time-consuming to split each stereo file into two mono ones since i have a large number of files.

[Shadi Ayyad]

please, do u have an idea about this ? This is a graduate project