iOs爲VOIP應用播放音頻

這是我第一篇文章，以stackoverflow。目前我正在爲ios開發一個voip應用程序。我想要做這樣的事情。iOs爲VOIP應用播放音頻

//in a thread 
while(callIsOnGoing){ 
    data = getDataFromNetwork() 
    playData() 
    sleep(10ms) 
}

但問題是，在IOS音頻「拉」模式工作（使用回調以獲取數據）。但我需要推動數據來播放它。我嘗試過AudioQueue，但在audioQueue中，我在回調之外的緩衝區中推入的數據不會播放，儘管回調被調用。

再次，我已經看到AVCaptureToAudioUnit示例由蘋果（http://developer.apple.com/library/ios/#samplecode/AVCaptureToAudioUnit/Introduction/Intro.html）他們在延遲音頻單元的情況下同步調用AudioUnitRender。我嘗試了類似的RemoteI/O音頻單元。但每次它返回OSStatus -50。下面

//in a separate thread 

    do {            // 5 
     int data_length = [NativeLibraryHelper GetData:(playBuff)]; 
     if(data_length == 0){ 

     }else{ 
     double numberOfFrameCount = data_length/player->audioStreamDesc->mBytesPerFrame; 
     currentSampleTime += numberOfFrameCount; 

     //AudioUnitRenderActionFlags flags = 0; 

     AudioTimeStamp timeStamp; 
     memset(&timeStamp, 0, sizeof(AudioTimeStamp)); 
     timeStamp.mSampleTime = currentSampleTime; 
     timeStamp.mFlags |= kAudioTimeStampSampleTimeValid; 

     AudioUnitRenderActionFlags flags = 0; 
     AudioBuffer buffer; 
     buffer.mNumberChannels = player->audioStreamDesc->mChannelsPerFrame; 
     buffer.mDataByteSize = data_length; 
     buffer.mData = malloc(data_length); 
     memcpy(buffer.mData, playBuff, data_length); 

     AudioBufferList audBuffList; 
     audBuffList.mBuffers[0] = buffer; 
     audBuffList.mNumberBuffers = 1; 

     printf("Audio REnder call back funciotn called with data size %d\n", data_length); 

     status = AudioUnitRender(audioUnitInstance, &flags, &timeStamp, 0, numberOfFrameCount, &audBuffList); 
     printf("osstatus %d\n", status); 
    }//end if else 
    CFRunLoopRunInMode (       // 6 
         kCFRunLoopDefaultMode,      // 7 
         0.25,          // 8 
         false          // 9 
         ); 
    //} while (aqData.mIsRunning); 
    [NSThread sleepForTimeInterval:.05]; 
}while (player->isRunning == YES);

的代碼給我帶音頻播放部分掙扎了一個多月。請幫忙。提前致謝。

來源

2013-07-04 Siddhartha Saif