Question about sample rate and frame rate sizes with Java Sound API -

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i inherited code uses java's sourcedataline sound api.

below how setup audioformat object. seems strange frame-rate , sample-rate set same. make sense? also, there point have 20000000 frame rate or sample rate? don't our ears top out @ 20000?

audioformat af = new audioformat(audioformat.encoding.pcm_signed, 20000000, 16, 1, 2, 20000000, true);

if stream encoded in pcm format , not compressed, frame contains samples each channel, 1 time index. if stream compressed, frame contains samples each channel, 1 or more time indexes. exact structure of frame depends on compression type.

check out audioformat class definition more details: http://download.oracle.com/javase/6/docs/api/javax/sound/sampled/audioformat.html

most sound systems consider top frequency human ear 22khz, that's why sampling frequency 44khz (according niquist rule).


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