AVFoundationを使用したビデオ録画

Question

AVFoundationを使用してビデオを録画しようとしています。セッションにのみビデオ入力を追加すると、すべて正常に機能しますが、オーディオ入力を追加するとビデオの録画が停止します（録画開始後すぐにデリゲートメソッドが呼び出されます）。ここに私のコードは次のとおりです。

-(void) recordVideo 
{  
self.session = [[AVCaptureSession alloc] init]; 

if([session canSetSessionPreset:AVCaptureSessionPresetMedium]) 
    session.sessionPreset = AVCaptureSessionPresetMedium; 


CALayer *viewLayer = [self.cameraView layer]; 

AVCaptureVideoPreviewLayer *captureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session]; 

captureVideoPreviewLayer.frame = viewLayer.bounds; 

[viewLayer addSublayer:captureVideoPreviewLayer]; 



self.videoInput = [AVCaptureDeviceInput deviceInputWithDevice:[self frontFacingCameraIfAvailable] error:nil]; 

self.audioInput = [AVCaptureDeviceInput deviceInputWithDevice:[self audioDevice] error:nil]; 


if(!videoInput) 
    NSLog(@"Couldn't create input!"); 

else 
{ 
    self.output= [[AVCaptureMovieFileOutput alloc] init]; 

    NSString *pathString = [[self outputPath]stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]; 

    NSURL *fileURL = [NSURL fileURLWithPath:pathString]; 


    [session beginConfiguration]; 

    [session removeInput:[self videoInput]]; 
    if([session canAddInput:videoInput]) 
     [session addInput:videoInput]; 

    [videoInput release]; 

    [session removeInput:[self audioInput]]; 
    if([session canAddInput:audioInput]) 
     [session addInput:audioInput]; 

    [audioInput release]; 

    if([session canAddOutput:output]) 
     [session addOutput:output]; 

    [output release]; 

    [session commitConfiguration]; 


    [session startRunning]; 

    [output startRecordingToOutputFileURL:fileURL recordingDelegate:self]; 
} 


- (void) captureOutput:(AVCaptureFileOutput *)captureOutput didStartRecordingToOutputFileAtURL:(NSURL *)fileURL fromConnections:(NSArray *)connections 
{ 
    NSLog(@"Recording Started at %@",fileURL); 

} 


- (void)captureOutput:(AVCaptureFileOutput *)captureOutput didFinishRecordingToOutputFileAtURL:(NSURL *)outputFileURL 
    fromConnections:(NSArray *)connections error:(NSError *)error 
{ 
    NSLog(@"Recording to file ended"); 


    [session stopRunning]; 
    [session release];   
} 



- (AVCaptureDevice *)frontFacingCameraIfAvailable 
{ 
    NSArray *videoDevices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo]; 
    AVCaptureDevice *captureDevice = nil; 

for (AVCaptureDevice *device in videoDevices) 
{ 
    if (device.position == AVCaptureDevicePositionBack) 
    { 
     captureDevice = device; 
     break; 
    } 
}  
return captureDevice; 
} 


- (AVCaptureDevice *) audioDevice 
{ 
    NSArray *devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeAudio]; 
    if ([devices count] > 0) { 
    return [devices objectAtIndex:0]; 
} 
return nil; 
} 

私はいくつかの一定時間後に[出力stopRecording]呼び出すが、私はオーディオ入力を追加するとき、それは単一のフレームを記録し、didFinishRecrodingデリゲートメソッドがすぐに呼ばれています。

誰でもこのコードで間違ったことを教えてもらえますか？

ありがとうございました

Answer 1

私はそれを理解しました。私はカテゴリーミキシングが必要でした。

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

if (setCategoryError) { NSLog(@"%@",[setCategoryError description]); } 

OSStatus propertySetError = 0; 
UInt32 allowMixing = true; 

propertySetError = AudioSessionSetProperty (kAudioSessionProperty_OverrideCategoryMixWithOthers, sizeof (allowMixing), &allowMixing);