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I would like to make an application similar to RedPhone on android. I took a look at SipDemo from and at the package.My question is, when you make/receive a call, how can you get the audio stream to encrypt/decrypt it before is being sent/played back to the user? Is there a tutorial about this somewhere? I am aware that I need a sip account and real devices with android 2.3. I would like to get the AudioStream before it's sent (for encryption) and to receive the AudioStream before it gets played-back to the user(for decryption).

please Help me out .

Thanks in advance :)

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up vote 2 down vote accepted

Take a look at countertap

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@securityshard Thanks for info dude:) – Rizvan Dec 22 '11 at 4:00

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