Sound/Silence in a wav file.

Question

Hi,

I am searching for a utility/code that could detect and let me know if my 1 minute wav file contains sound or not ? Other way, if it could detect the duration of the silence(if exists) at any position in the wav file, that would also server the purpose.

Does SOX support any command for that ? I tried with Java, but didnt found anything in JMF.

Thanks

Vivek

Answer 1

SoX does have the ability to trim silence, but I'm not sure whether that helps you:

silence [-l] above-periods [duration threshold[d|%] [below-periods duration threshold[d|%]]

Removes silence from the beginning, middle, or end of the audio. `Silence' is determined by a specified threshold.

Answer 2

You could easily write your wave file processor, it's an easy header and then just simple data. You can easily find out the sample size, 8 or 16 bits, then read the file sample by sample if you find a sequence of samples with the value of 0 then you got silence. Measure how many samples are 0 and use the sampling rate (also in the header) to calculate the duration.

Answer 3

Audacity does this and is OpenSourced on sourceforge.net, so you should be able to gleen all the example code you need.