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troubleshooting Question

VAD, or basic voice detection

Avatar of billysdomain
billysdomainFlag for United Kingdom of Great Britain and Northern Ireland asked on
ProgrammingVoice Over IPVoice Recognition
3 Comments1 Solution681 ViewsLast Modified:

Does anyone have any tricks to detect voice/speech in a PCM audio block?

Lets say i have a 25ms block of PCM audio, before i stream this to the network, i would like to embed a value in its header which has computed the probability of speech within that packet (it can also refer to the result of the previous packet as well if desired)

I am currently doing this by computing the Power of each packet (i have attached a code snippet), i then embed the average of this computation in the header.

The recieving unit will use this value to try and automate a PTT (Push to talk simplex) system

Im wondering if anyone could suggest a better/more precise way of doing this - code snippets a bonus!

Im after C++ or C code.

I have looked into the various G*** offerings but everything looks way complicated.

Many thanks
void GetPower(short *signal, int numSamples)
	int i;
	float amp;

	for (i = 0; i < numSamples; i++){
		amp = (float) abs(signal[i]);
		FPower += amp * amp;

	FPowerAdditions += numSamples;
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