2009-09-22 67 views
3

我试图让音频队列在iphone应用程序上工作,并且每当调用AudioQueueStart时它都会提供“fmt?”结果码(kAudioFormatUnsupportedDataFormatError)。在下面的代码中,我将格式设置为kAudioFormatLinearPCM,该格式肯定受支持。我究竟做错了什么?AudioQueueStart报告不支持的格式

data.mDataFormat.mSampleRate = 44100; 
data.mDataFormat.mFormatID = kAudioFormatLinearPCM; 
data.mDataFormat.mFormatFlags = 0; 
data.mDataFormat.mBytesPerPacket = 4; 
data.mDataFormat.mFramesPerPacket = 1; 
data.mDataFormat.mBytesPerFrame = 4; 
data.mDataFormat.mChannelsPerFrame = 2; 
data.mDataFormat.mBitsPerChannel = 16; 

OSStatus status; 

status = AudioQueueNewOutput(&data.mDataFormat, audioCallback, &data, CFRunLoopGetCurrent(), kCFRunLoopCommonModes, 0, &data.mQueue); 

for (int i = 0; i < NUMBUFFERS; ++i) 
{ 
    status = AudioQueueAllocateBuffer (data.mQueue, BUFFERSIZE, &data.mBuffers[i]); 
    audioCallback (&data, data.mQueue, data.mBuffers[i]); 
} 

Float32 gain = 1.0; 
status = AudioQueueSetParameter (data.mQueue, kAudioQueueParam_Volume, gain); 

status = AudioQueueStart(data.mQueue, NULL); 

数据是类型audioData其是这样的:

typedef struct _audioData { 
AudioQueueRef mQueue; 
AudioQueueBufferRef mBuffers[NUMBUFFERS]; 
AudioStreamBasicDescription mDataFormat; 

} audioData;

谢谢

+0

嗨! 我有同样的问题。更改不同的标志对我无用。可能是iPad模拟器不支持录音? – 2011-01-30 14:29:45

回答

0

事实证明,我需要设置一些标志。它的工作原理与

data.mDataFormat.mFormatFlags = kLinearPCMFormatFlagIsBigEndian | kLinearPCMFormatFlagIsSignedInteger | kLinearPCMFormatFlagIsPacked; 

编辑:实际上,不使用kLinearPCMFormatFlagIsBigEndian,似乎与这种格式应该是小端。