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我正在尝试处理使用ExtAudioFile. 但是，当我尝试将此数据放入循环缓冲区时，我听到了几个故障。

在下面的示例代码中，我将数据从“inBuffer”直接传递到“outBuffer”（两者都是TPCircularBufferMichael Tyson 的类型）。两个缓冲区的大小都是 10 x numberOfFrames * sizeof(float)。客户端流格式是带有浮点样本的单声道。

为什么我什至没有处理任何数据就听到这些故障？如果没有循环缓冲区，声音会很好地流动。我做错了什么或者另一种方法会更好？

static OSStatus recordingCallback(
                                  void*                       inRefCon,
                                  AudioUnitRenderActionFlags* ioActionFlags,
                                  const AudioTimeStamp*       inTimeStamp,
                                  UInt32                      inBusNumber,
                                  UInt32                      inNumberFrames,
                                  AudioBufferList*            ioData){
    PlayAudioFile* player = (__bridge PlayAudioFile*)inRefCon;
    Info *info = (Info *)player.info;


    ExtAudioFileRead(info->extAudioFile, &inNumberFrames, info->inputBuffer);

    if (inNumberFrames == 0) {
        ExtAudioFileSeek(info->extAudioFile, 0);
    }

    // Put data in circular buffer
     TPCircularBufferProduceBytes(info->inBuffer, info->inputBuffer->mBuffers[0].mData, info->inputBuffer->mBuffers[0].mDataByteSize);


    UInt32 frameSize = inNumberFrames*sizeof(float);
    if (info->inBuffer->fillCount >= frameSize) {
        int32_t availableBytes;

        float *tail = TPCircularBufferTail(info->inBuffer, &availableBytes);
        if (availableBytes > frameSize){
            memcpy(info->tempBuffer, tail, frameSize);
            TPCircularBufferConsume(info->inBuffer, frameSize);

            // Currently, data is not processed but just put to the output buffer

            TPCircularBufferProduceBytes(info->outBuffer, info->tempBuffer, frameSize);
        }
    }

    return noErr;
}



static OSStatus renderCallback(
                               void*                       inRefCon,
                               AudioUnitRenderActionFlags* ioActionFlags,
                               const AudioTimeStamp*       inTimeStamp,
                               UInt32                      inBusNumber,
                               UInt32                      inNumberFrames,
                               AudioBufferList*            ioData){
    PlayAudioFile* player = (__bridge PlayAudioFile*)inRefCon;
    Info *info = (Info *)play.info;

    for (int i=0; i < ioData->mNumberBuffers; i++) {
        AudioBuffer buffer = ioData->mBuffers[i];

        if (info->outBuffer->fillCount > ioData->mBuffers[0].mDataByteSize) {

            int32_t availableBytes;
            float *tail = TPCircularBufferTail(info->outBuffer, &availableBytes);

            memcpy(buffer.mData, tail, buffer.mDataByteSize);
            TPCircularBufferConsume(info->outBuffer, buffer.mDataByteSize);

   /* Messaging is not used for this example
            // Notify delegate
            if ([player.delegate respondsToSelector:@selector(player:audioBuffer:bufferSize:)])
            {
                [player.delegate player:player
                            audioBuffer:buffer.mData
                             bufferSize:inNumberFrames];
            }
    */
        }
        else {
            memset((char*)ioData->mBuffers[i].mData, 0, ioData->mBuffers[i].mDataByteSize  * info->clientFormat.mBytesPerFrame);

        }
    }
    return noErr;
}

编辑 根据下面的答案，我通过在回调函数之外分配和释​​放内存以及增加循环缓冲区的大小来修改代码。不幸的是，声音仍然比没有循环缓冲区的情况差。这些故障还有其他原因吗？

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1 回答 1

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分配或释放内存不应在音频回调中完成。也不应该发送 Objective C 消息。

渲染回调应始终将数据放入缓冲区列表缓冲区中。但是您的代码缺少执行此操作的 else 语句。尝试更大的循环缓冲区并确保在开始渲染回调之前它已充分预填充。

于 2016-03-01T15:34:06.153 回答