关于ios：音频队列接口可以处理40ms音频帧吗？

Audio Queue Interface can deal with 40ms Audio Frame?

我正在尝试以40ms的时间段录制音频。
音频队列接口可以处理40ms音频帧？
如果"是"，那么我们如何实现呢？

谢谢。

是的，可能的话，您需要相应地配置configure AudioQueue，

基本上，AudioQueue缓冲区的大小必须设置为40ms，所以大约为

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int AQRecorder::ComputeRecordBufferSize(const AudioStreamBasicDescription *format, float seconds)
{
int packets, frames, bytes = 0;
try {
frames = (int)ceil(seconds * format->mSampleRate);

if (format->mBytesPerFrame > 0)
bytes = frames * format->mBytesPerFrame;
else {
UInt32 maxPacketSize;
if (format->mBytesPerPacket > 0)
maxPacketSize = format->mBytesPerPacket; // constant packet size
else {
UInt32 propertySize = sizeof(maxPacketSize);
XThrowIfError(AudioQueueGetProperty(mQueue, kAudioQueueProperty_MaximumOutputPacketSize, &maxPacketSize,
&propertySize),"couldn't get queue's maximum output packet size");
}
if (format->mFramesPerPacket > 0)
packets = frames / format->mFramesPerPacket;
else
packets = frames; // worst-case scenario: 1 frame in a packet
if (packets == 0) // sanity check
packets = 1;
bytes = packets * maxPacketSize;
}
} catch (CAXException e) {
char buf[256];
return 0;
}
return bytes;
}

并设置格式

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void AQRecorder::SetupAudioFormat(UInt32 inFormatID)
{
AudioStreamBasicDescription sRecordFormat;
FillOutASBDForLPCM (sRecordFormat,
SAMPLING_RATE,
1,
8*BYTES_PER_PACKET,
8*BYTES_PER_PACKET,
false,
false
);
memset(&mRecordFormat, 0, sizeof(mRecordFormat));

mRecordFormat.SetFrom(sRecordFormat);
}

在我的情况下，

这些宏的值为

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#define SAMPLING_RATE 16000
#define kNumberRecordBuffers 3
#define BYTES_PER_PACKET 2