Audio Frequency in Android

I have written a code for getting frequency of audio.

I have used Zero Crossing algorithm to convert short array into frequency(int). It works fine.

Whenever I play 2500Hz Audio Frequency in my PC It gives me perfect value.

e.g. 2500Hz=1400

If I play 2500Hz Audio Frequency for 10sec it gives me 1400 for 10sec.

So I can say that it works fine without any problem. There is no any issue with code.

But Now My problem is that whenever I change Device the output also changed.

e.g above output I get when I use Samsung GT-i5700.(Android 2.2)

But When I use Micro-max A-60(Android 2.1) It 开发者_开发问答gives me output like that 2500Hz=771.

I can't find the reason,why output is changed when device is changed?

How can I solve this?

Is there any connection between android version and audio frequency?

Note:

I have cable which gives output from PC speaker to Devices MIC. So I can play Tone in PC and send it directly to Device MIC.

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If the calculated frequency changes when you change handset then I would expect that your code is in fact NOT fine. Have you tried a third handset and observed if the results it gives match one of the previous 2 handsets?

If you are looking for potentially more accurate solutions (saying a 2500Hz tone outputs 1400 seems odd to me) look at How do you analyse the fundamental frequency of a PCM or WAV sample? for options.

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Using this implementation on Android, I have found that it rarely gets the correct frequency as well. However, it does produce a "consistent" value when it is hearing a tone versus random speech, which is still useful.