10

我正在学习核心音频。由于某种原因，处理图的声音只能通过较弱的“耳扬声器”（当您将设备放在耳边时）播放，而不是通过 iPhone 的常规扬声器播放。

这是设置音频会话的代码，但我看不到它配置音频路由的位置：

- (void) setupAudioSession {

    AVAudioSession *mySession = [AVAudioSession sharedInstance];

    // Specify that this object is the delegate of the audio session, so that
    //    this object's endInterruption method will be invoked when needed.
    [mySession setDelegate: self];

    // Assign the Playback category to the audio session.
    NSError *audioSessionError = nil;
    [mySession setCategory: AVAudioSessionCategoryPlayAndRecord//AVAudioSessionCategoryPlayback
                     error: &audioSessionError];

    if (audioSessionError != nil) {

        NSLog (@"Error setting audio session category.");
        return;
    }

    // Request the desired hardware sample rate.
    self.graphSampleRate = 44100.0;    // Hertz

    [mySession setPreferredHardwareSampleRate: graphSampleRate
                                        error: &audioSessionError];

    if (audioSessionError != nil) {

        NSLog (@"Error setting preferred hardware sample rate.");
        return;
    }

    // Activate the audio session
    [mySession setActive: YES
                   error: &audioSessionError];

    if (audioSessionError != nil) {

        NSLog (@"Error activating audio session during initial setup.");
        return;
    }

    // Obtain the actual hardware sample rate and store it for later use in the audio processing graph.
    self.graphSampleRate = [mySession currentHardwareSampleRate];

    // Register the audio route change listener callback function with the audio session.
    AudioSessionAddPropertyListener (
        kAudioSessionProperty_AudioRouteChange,
        audioRouteChangeListenerCallback,
        self
    );
}

使用音频单元播放声音时，您在核心音频的哪个位置说“通过扬声器播放”？

4

2 回答 2

7

您可以使用setCategory withOption:

[mySession setCategory:AVAudioSessionCategoryPlayAndRecord withOptions:AVAudioSessionCategoryOptionDefaultToSpeaker error:&audioSessionError];
于 2014-03-11T13:58:25.930 回答
4

我有同样的问题。原来这与“播放和记录”类别有关。只需要重定向音频输出。

UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_Speaker;

AudioSessionSetProperty (
    kAudioSessionProperty_OverrideAudioRoute,
    sizeof (audioRouteOverride),
    &audioRouteOverride
);

资源：

于 2013-02-12T15:24:28.920 回答