Question

我正在尝试使用AVFoundation在我的iPhone应用中录制视频。但每当我点击“录制”按钮时，应用程序都会崩溃

- [AVCaptureMovieFileOutput startRecordingToOutputFileURL：recordingDelegate：] - 无活动/启用连接。

我知道同样的问题，但是没有一个答案对我有帮助。我的问题是相同的代码完全适用于另一个应用程序，当我尝试在这个应用程序中使用完全相同的代码 - 崩溃。但照片捕捉仍然正常。

在此处添加我的代码 - 请帮助我，提前致谢

  -(void)viewDidLoad
  {
 [super viewDidLoad];
 self.captureSession = [[AVCaptureSession alloc] init];

   AVCaptureDevice *videoDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
AVCaptureDevice *audioDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeAudio];

  self.videoInput = [AVCaptureDeviceInput deviceInputWithDevice:videoDevice error:nil];
  self.audioInput = [[AVCaptureDeviceInput alloc] initWithDevice:audioDevice error:nil];

  self.stillImageOutput = [[AVCaptureStillImageOutput alloc] init];
  NSDictionary *stillImageOutputSettings = [[NSDictionary alloc] initWithObjectsAndKeys:
                                          AVVideoCodecJPEG, AVVideoCodecKey, nil];
  [self.stillImageOutput setOutputSettings:stillImageOutputSettings];

  self.movieOutput = [[AVCaptureMovieFileOutput alloc] init];

  [self.captureSession addInput:self.videoInput];
  [self.captureSession addOutput:self.stillImageOutput];




   previewLayer = [AVCaptureVideoPreviewLayer layerWithSession:self.captureSession];
   UIView *aView = self.view;
   previewLayer.frame = CGRectMake(70, 190, 270, 270);
   [aView.layer addSublayer:previewLayer];


     }




  -(NSURL *) tempFileURL
  {
    NSString *outputPath = [[NSString alloc] initWithFormat:@"%@%@", NSTemporaryDirectory(), @"output.mov"];
    NSURL *outputURL = [[NSURL alloc] initFileURLWithPath:outputPath];
   NSFileManager *manager = [[NSFileManager alloc] init];
   if ([manager fileExistsAtPath:outputPath])
    {
    [manager removeItemAtPath:outputPath error:nil];
    }


    return outputURL;
  }

  -(IBAction)capture:(id)sender
  {

    if (self.movieOutput.isRecording == YES)
    {
         [self.movieOutput stopRecording];
    }
    else
    {
         [self.movieOutput startRecordingToOutputFileURL:[self tempFileURL] recordingDelegate:self];
    }

      }





   -(void)captureOutput:(AVCaptureFileOutput *)captureOutput  didFinishRecordingToOutputFileAtURL:(NSURL *)outputFileURL
  fromConnections:(NSArray *)connections
            error:(NSError *)error
  {


   BOOL recordedSuccessfully = YES;
  if ([error code] != noErr)
    {
    id value = [[error userInfo] objectForKey:AVErrorRecordingSuccessfullyFinishedKey];
    if (value)
        recordedSuccessfully = [value boolValue];
    NSLog(@"A problem occurred while recording: %@", error);
   }
  if (recordedSuccessfully) {
    ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];

    [library writeVideoAtPathToSavedPhotosAlbum:outputFileURL
                                completionBlock:^(NSURL *assetURL, NSError *error)
     {
         UIAlertView *alert;
         if (!error)
         {
             alert = [[UIAlertView alloc] initWithTitle:@"Video Saved"
                                                message:@"The movie was successfully saved to you photos library"
                                               delegate:nil
                                      cancelButtonTitle:@"OK"
                                      otherButtonTitles:nil, nil];
         }
         else
         {
             alert = [[UIAlertView alloc] initWithTitle:@"Error Saving Video"
                                                message:@"The movie was not saved to you photos library"
                                               delegate:nil
                                      cancelButtonTitle:@"OK"

                                      otherButtonTitles:nil, nil];
         }

         [alert show];
     }
     ];
    }

  }

Answer 1

我在更改videoDevice activeFormat时遇到了同样的问题，后来想要录制视频。因为我使用的是最优质的视频，所以我必须将sessionPreset设置为高，如下面的

_session.sessionPreset = AVCaptureSessionPresetHigh;

它对我有用！：）

Answer 2

因为目前您没有活动连接来录制视频到文件在记录到输出文件之前检查连接活动状态：

AVCaptureConnection *c = [self.movieOutput connectionWithMediaType:AVMediaTypeVideo];
if (c.active) {
  //connection is active
} else {
  //connection is not active
  //try to change self.captureSession.sessionPreset,
  //or change videoDevice.activeFormat
}

如果连接未激活，请尝试更改captureSession.sessionPreset或videoDevice.activeFormat。
重复，直到您设置了有效格式（这意味着c.active == YES）。然后你可以将视频录制到输出文件。

Answer 3

您的代码中缺少一些内容：

您忘记将movieOutput添加到captureSession
与audioInput
您的所有会话配置都需要[_captureSession beginConfiguration]和[_captureSession commitConfiguration]
对于录音，您需要将AVAudioSession设置为正确的类别。

以下是您的代码更新：

- (void)viewDidLoad
{
    [super viewDidLoad];

    NSError *error = nil;
    [[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryRecord
                                           error:&error];

    if(!error)
    {
        [[AVAudioSession sharedInstance] setActive:YES error:&error];

        if(error) NSLog(@"Error while activating AudioSession : %@", error);
    }
    else
    {
        NSLog(@"Error while setting category of AudioSession : %@", error);
    }

    self.captureSession = [[AVCaptureSession alloc] init];

    AVCaptureDevice *videoDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    AVCaptureDevice *audioDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeAudio];

    self.videoInput = [AVCaptureDeviceInput deviceInputWithDevice:videoDevice error:nil];
    self.audioInput = [[AVCaptureDeviceInput alloc] initWithDevice:audioDevice error:nil];

    self.stillImageOutput = [[AVCaptureStillImageOutput alloc] init];
    NSDictionary *stillImageOutputSettings = [[NSDictionary alloc] initWithObjectsAndKeys:
                                              AVVideoCodecJPEG, AVVideoCodecKey, nil];
    [self.stillImageOutput setOutputSettings:stillImageOutputSettings];

    self.movieOutput = [[AVCaptureMovieFileOutput alloc] init];

    [self.captureSession beginConfiguration];

    [self.captureSession addInput:self.videoInput];
    [self.captureSession addInput:self.audioInput];
    [self.captureSession addOutput:self.movieOutput];
    [self.captureSession addOutput:self.stillImageOutput];

    [self.captureSession commitConfiguration];

    AVCaptureVideoPreviewLayer *previewLayer = [AVCaptureVideoPreviewLayer layerWithSession:self.captureSession];
    previewLayer.frame = CGRectMake(0, 0, 320, 500);
    [self.view.layer addSublayer:previewLayer];

    [self.captureSession startRunning];
}

- (IBAction)toggleRecording:(id)sender
{
    if(!self.movieOutput.isRecording)
    {
        [self.recordButton setTitle:@"Stop" forState:UIControlStateNormal];

        NSString *outputPath = [NSTemporaryDirectory() stringByAppendingPathComponent:@"output.mp4"];

        NSFileManager *manager = [[NSFileManager alloc] init];
        if ([manager fileExistsAtPath:outputPath])
        {
            [manager removeItemAtPath:outputPath error:nil];
        }

        [self.movieOutput startRecordingToOutputFileURL:[NSURL fileURLWithPath:outputPath]
                                      recordingDelegate:self];
    }
    else
    {
        [self.recordButton setTitle:@"Start recording" forState:UIControlStateNormal];

        [self.movieOutput stopRecording];
    }
}

- (void)captureOutput:(AVCaptureFileOutput *)captureOutput didFinishRecordingToOutputFileAtURL:(NSURL *)outputFileURL fromConnections:(NSArray *)connections error:(NSError *)error
{
    NSLog(@"Did finish recording, error %@ | path %@ | connections %@", error, [outputFileURL absoluteString], connections);
}

希望这有帮助

Answer 4

我找到了这个错误的原因。检查你的会话＆＃34; setSessionPreset＆＃34;设置，照片的分辨率设置与视频不同，对于iPhone5，后置摄像头的视频分辨率为1920 * 1080，前置摄像头为1280 * 720，照片最高分辨率为3264 * 2488，因此，如果您将错误分辨率设置为视频，则不会激活连接。

AVCaptureMovieFileOutput - 没有活动/启用的连接

4 个答案: