一起使用AVCaptureSession和AVAudioPlayer [英] Using AVCaptureSession and AVAudioPlayer together

问题描述

我能够录制视频并将影片正确输出到文件中。但是，在尝试使用AVAudioPlayer播放某些音频时，我遇到了视频录制（无视频输出）的问题。这是否意味着我不能同时使用AVCaptureSession和AVAudioPlayer？这是我创建捕获会话和播放音频的代码。首先启动视频捕获，然后在捕获期间，我想播放一些音频。非常感谢您的帮助。

I am able to record video and output the movie to a file correctly. However, I have a problem with video recording (no video ouput) when trying to use AVAudioPlayer to play some audio. Does it mean that I cannot use AVCaptureSession and AVAudioPlayer at the same time? Here is my code to create the capture session and to play the audio. The video capture is started first, then during the capturing, I want to play some audio. Thanks so much for any help.

创建捕获会话以记录视频（带音频）的代码 - 输出到.mov文件：

Code to create the capture session to record video (with audio) - output to a .mov file:

- (void)addVideoInput
    AVCaptureDevice *audioDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeAudio];
    //... also some code for setting up videoDevice/frontCamera
    NSError *error;
    AVCaptureDeviceInput *videoIn = [AVCaptureDeviceInput 
    deviceInputWithDevice:frontCamera error:&error];
    AVCaptureDeviceInput *audioIn = [AVCaptureDeviceInput 
    deviceInputWithDevice:audioDevice error:&error];
    if (!error) {
         if ([captureSession canAddInput:audioIn])
              [captureSession addInput:audioIn];
         else
              NSLog(@"Couldn't add audio input.");  
         if ([captureSession canAddInput:videoIn])
              [captureSession addInput:videoIn];
         else
              NSLog(@"Couldn't add video input.");
}
- (void)addVideoOutput
{
     AVCaptureMovieFileOutput *m_captureFileOutput = [[AVCaptureMovieFileOutput alloc] init];
     [captureSession addOutput:m_captureFileOutput];

     [captureSession startRunning];

     NSString *docDir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
     NSMutableString *filePath = [NSMutableString stringWithString:@"Movie.mov"];
     NSString* fileRoot = [docDir stringByAppendingPathComponent:filePath];
     NSURL *fileURL = [NSURL fileURLWithPath:fileRoot];

     AVCaptureConnection *videoConnection = NULL;

     for ( AVCaptureConnection *connection in [m_captureFileOutput connections] ) 
     {
         for ( AVCaptureInputPort *port in [connection inputPorts] ) 
         {
             if ( [[port mediaType] isEqual:AVMediaTypeVideo] ) 
             {
                 videoConnection = connection;

             }
         }
     }

     [videoConnection setVideoOrientation:AVCaptureVideoOrientationLandscapeRight]; 


     [m_captureFileOutput startRecordingToOutputFileURL:fileURL recordingDelegate:self];
     [m_captureFileOutput release];
}

播放音频的代码，此功能在视频捕获会话期间调用。如果我不调用此功能，则会录制视频，并且我可以保存到.mov文件。但是，如果我调用此函数，则没有输出.mov文件。

Code to play the audio, this function is call during the video capture session. If I don't call this function, the video is recorded and I am able to save to the .mov file. However, if I call this function, there's no output .mov file.

- (void)playAudio
{
     NSString *soundFilePath = [[NSBundle mainBundle] pathForResource:@"AudioFile" ofType:@"mp3"];
     NSURL *fileURL = [[NSURL alloc] initFileURLWithPath:soundFilePath];
     AVAudioPlayer *newPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:fileURL error:nil];
     [fileURL release];
     self.audioPlayer = newPlayer;
     [newPlayer release];
     [audioPlayer setDelegate:self];
     [audioPlayer prepareToPlay];
     [audioPlayer play];
}

推荐答案

我通过设置解决了问题音频会话。在创建播放音频的音频播放器对象之前，我调用了以下函数。这样，我就能够录制视频（带音频）并同时播放音频。

I fixed the problem by setting up the audio session. I called the following function before creating the audio player object to play the audio. That way, I was able to record video (with audio) and play audio at the same time.

- (void)setupAudioSession {

        static BOOL audioSessionSetup = NO;
        if (audioSessionSetup) {
                return;   
        }
        [[AVAudioSession sharedInstance] setCategory: AVAudioSessionCategoryPlayback error: nil];
        UInt32 doSetProperty = 1;

        AudioSessionSetProperty (kAudioSessionProperty_OverrideCategoryMixWithOthers, sizeof(doSetProperty), &doSetProperty);

        [[AVAudioSession sharedInstance] setActive: YES error: nil];

         audioSessionSetup = YES;

}


- (void)playAudio
{
         [self setupAudioSession];
         NSString *soundFilePath = [[NSBundle mainBundle] pathForResource:@"AudioFile" ofType:@"mp3"];
         NSURL *fileURL = [[NSURL alloc] initFileURLWithPath:soundFilePath];
         AVAudioPlayer *newPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:fileURL error:nil];
         [fileURL release];
         self.audioPlayer = newPlayer;
         [newPlayer release];
         [audioPlayer setDelegate:self];
         [audioPlayer prepareToPlay];
         [audioPlayer play];
    }

这篇关于一起使用AVCaptureSession和AVAudioPlayer的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！