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iPhone播放AudioQueue在调试期间在断点处暂停后停止/无法继续

audioqueue playback debugging xcode ios

zerojarvis · 技术社区 · 15 年前

出于某种原因,在调试期间在断点处停止似乎会终止我的音频队列播放。

AudioQueue将播放音频输出。
触发断点以暂停我的iPhone应用程序。
函数仍在被调用。)

由于调试器暂停了应用程序(例如,不是一个来电),所以这不是典型的iPhone中断,所以 AudioSession interruption callbacks do not get triggered like in this solution .

我正在使用 three AudioQueue buffers

多线程和单线程模式都会出现问题。

是否存在在调试会话期间无法暂停和恢复AudioSessions或AudioQueues的已知问题?

有人了解iPhone音频队列的内部工作原理吗?

1 回复 | 直到 8 年前

zerojarvis 15 年前

在玩了几天之后,在发布到StackOverflow之前,我今天就找到了答案。想想看!

只需调用我的“准备函数”重新创建AudioQueue

SetupNewQueue(mDataFormat.mSampleRate, mDataFormat.mChannelsPerFrame);
StartQueue(true);

因此,检测您的AudioQueue何时“死亡”。在我的例子中,我将数据写入一个输入缓冲区,由AudioQueue回调“拉入”。如果在某个时间内没有发生,或者在输入缓冲区的X字节数被填满之后,我就重新创建AudioQueue。

这似乎

void AQPlayer::SetupNewQueue(double inSampleRate, UInt32 inChannelsPerFrame)
{
    //Prep AudioStreamBasicDescription
    mDataFormat.mSampleRate = inSampleRate;
    mDataFormat.SetCanonical(inChannelsPerFrame, YES);

    XThrowIfError(AudioQueueNewOutput(&mDataFormat, AQPlayer::AQBufferCallback, this, 
                                    NULL, kCFRunLoopCommonModes, 0, &mQueue), "AudioQueueNew failed");

    // adjust buffer size to represent about a half second of audio based on this format
    CalculateBytesForTime(mDataFormat, kBufferDurationSeconds, &mBufferByteSize, &mNumPacketsToRead);
    ctl->cmsg(CMSG_INFO, VERB_NOISY, "AQPlayer Buffer Byte Size: %d, Num Packets to Read: %d\n", (int)mBufferByteSize, (int)mNumPacketsToRead);

    mBufferWaitTime = mNumPacketsToRead / mDataFormat.mSampleRate * 0.9;

    XThrowIfError(AudioQueueAddPropertyListener(mQueue, kAudioQueueProperty_IsRunning, isRunningProc, this), "adding property listener");

    //Allocate AQ buffers (assume we are using CBR (constant bitrate)
    for (int i = 0; i < kNumberBuffers; ++i) {
        XThrowIfError(AudioQueueAllocateBuffer(mQueue, mBufferByteSize, &mBuffers[i]), "AudioQueueAllocateBuffer failed");
    }
...
}

OSStatus AQPlayer::StartQueue(BOOL inResume)
{   
// if we are not resuming, we also should restart the file read index
    if (!inResume)
        mCurrentPacket = 0; 

    // prime the queue with some data before starting
    for (int i = 0; i < kNumberBuffers; ++i) {
        mBuffers[i]->mAudioDataByteSize = mBuffers[i]->mAudioDataBytesCapacity;
        memset( mBuffers[i]->mAudioData, 0, mBuffers[i]->mAudioDataByteSize );

        XThrowIfError(AudioQueueEnqueueBuffer( mQueue,
                                mBuffers[i],
                                0,
                                NULL ),"AudioQueueEnqueueBuffer failed");
    }

    OSStatus status;
    status = AudioSessionSetActive( true );
    XThrowIfError(status, "\n\n*** AudioSession failed to become active *** \n\n");

    status = AudioQueueStart(mQueue, NULL);
    XThrowIfError(status, "\n\n*** AudioQueue failed to start *** \n\n");

    return status;
}