iphone - 使用 AVCapture 分别但同时写入视频和音频

Question

我想分别捕获视频和音频，但同时捕获，所以最后我的 NSDocuments 文件夹中有一个 .mp4 文件和一个 .wav(或类似的音频格式)。到目前为止我有这个，但它甚至没有调用 - (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection。

知道这里出了什么问题吗？

#import "VideoCaptureViewController.h"
#import <AssetsLibrary/AssetsLibrary.h>
#import "SMFileManager.h"



@interface VideoCaptureViewController () {

    AVCaptureSession *session_;
    AVCaptureDevice *captureDevice_;
    AVCaptureDeviceInput *deviceInput_;
    AVCaptureMovieFileOutput *captureMovieFileOutput_;
    BOOL recording_;

    AVCaptureAudioDataOutput *audioDataOutput_;


    NSString *filePathCapturedVideo_;

}

- (void) toggleRecording;
- (void) endRecording;

@end

@implementation VideoCaptureViewController
@synthesize delegate;
@synthesize previewLayer;

- (void)viewDidLoad
{
    [super viewDidLoad];


    session_ = [[AVCaptureSession alloc] init];

    // Add video input.
    NSArray *videoDevices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
    // AVCaptureDevice *captureDevice = nil;
    captureDevice_ = nil;
    for (AVCaptureDevice *device in videoDevices) {
        if (device.position == AVCaptureDevicePositionFront) {
            captureDevice_ = device;
            break;
        }
    }

    // AVCaptureDevice *videoDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    if (captureDevice_) {
        NSError *error;
        deviceInput_ = [AVCaptureDeviceInput deviceInputWithDevice:captureDevice_ error:&error];
        if (!error){
            if ([session_ canAddInput:deviceInput_])
                [session_ addInput:deviceInput_];
            else
                NSLog(@"Couldn't add video input");
        } else {
            NSLog(@"Couldn't create video input");
        }
    } else {
        NSLog(@"Couldn't create video capture device");
    }


    //ADD AUDIO INPUT
    NSLog(@"Adding audio input");
    AVCaptureDevice *audioCaptureDevice = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeAudio];
    NSError *error = nil;
    AVCaptureDeviceInput *audioInput = [AVCaptureDeviceInput deviceInputWithDevice:audioCaptureDevice error:&error];

    if (audioInput) {
        [session_ addInput:audioInput];
    }

    //----- ADD OUTPUTS -----

    // audio 
    audioDataOutput_= [[AVCaptureAudioDataOutput alloc] init];
    [session_ addOutput:audioDataOutput_];

    dispatch_queue_t queue = dispatch_queue_create("MyQueue", NULL);
    [audioDataOutput_ setSampleBufferDelegate:self queue:queue];
    dispatch_release(queue);

    //ADD VIDEO PREVIEW LAYER
    NSLog(@"Adding video preview layer");
    [self setPreviewLayer:[[[AVCaptureVideoPreviewLayer alloc] initWithSession:session_] autorelease]];
    previewLayer.orientation = AVCaptureVideoOrientationPortrait;       //<<SET ORIENTATION.  You can deliberatly set this wrong to flip the image and may actually need to set it wrong to get the right image
    [[self previewLayer] setVideoGravity:AVLayerVideoGravityResizeAspectFill];


    //ADD MOVIE FILE OUTPUT
    NSLog(@"Adding movie file output");
    captureMovieFileOutput_ = [[AVCaptureMovieFileOutput alloc] init];

//  Float64 TotalSeconds = 60;          //Total seconds
//  int32_t preferredTimeScale = CAPTURE_FRAMES_PER_SECOND; //Frames per second
//  CMTime maxDuration = CMTimeMakeWithSeconds(TotalSeconds, preferredTimeScale);   //<<SET MAX DURATION
//  captureMovieFileOutput_.maxRecordedDuration = maxDuration;

    captureMovieFileOutput_.minFreeDiskSpaceLimit = 1024 * 1024;                        //<<SET MIN FREE SPACE IN BYTES FOR RECORDING TO CONTINUE ON A VOLUME

    if ([session_ canAddOutput:captureMovieFileOutput_])
        [session_ addOutput:captureMovieFileOutput_];

    //SET THE CONNECTION PROPERTIES (output properties)
    [self CameraSetOutputProperties];           //(We call a method as it also has to be done after changing camera)



    //----- SET THE IMAGE QUALITY / RESOLUTION -----
    //Options:
    //  AVCaptureSessionPresetHigh - Highest recording quality (varies per device)
    //  AVCaptureSessionPresetMedium - Suitable for WiFi sharing (actual values may change)
    //  AVCaptureSessionPresetLow - Suitable for 3G sharing (actual values may change)
    //  AVCaptureSessionPreset640x480 - 640x480 VGA (check its supported before setting it)
    //  AVCaptureSessionPreset1280x720 - 1280x720 720p HD (check its supported before setting it)
    //  AVCaptureSessionPresetPhoto - Full photo resolution (not supported for video output)
    NSLog(@"Setting image quality");
    [session_ setSessionPreset:AVCaptureSessionPresetHigh];
    if ([session_ canSetSessionPreset:AVCaptureSessionPreset1280x720])  {   //Check size based configs are supported before setting them
        NSLog(@"1280x720 confirmed!");
        [session_ setSessionPreset:AVCaptureSessionPreset1280x720];
    }


    //----- DISPLAY THE PREVIEW LAYER -----
    //Display it full screen under out view controller existing controls
    NSLog(@"Display the preview layer");
    CGRect layerRect = [[[self view] layer] bounds];
    [previewLayer setBounds:layerRect];
    [previewLayer setPosition:CGPointMake(CGRectGetMidX(layerRect), CGRectGetMidY(layerRect))];
    //[[[self view] layer] addSublayer:[[self CaptureManager] previewLayer]];
    //We use this instead so it goes on a layer behind our UI controls (avoids us having to manually bring each control to the front):
    UIView *CameraView = [[[UIView alloc] init] autorelease];
    [[self view] addSubview:CameraView];
    [self.view sendSubviewToBack:CameraView];

    [[CameraView layer] addSublayer:previewLayer];


    //----- START THE CAPTURE SESSION RUNNING -----
    [session_ startRunning];
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    return (interfaceOrientation == UIDeviceOrientationPortrait);
}


//********** VIEW WILL APPEAR **********
//View about to be added to the window (called each time it appears)
//Occurs after other view's viewWillDisappear
- (void)viewWillAppear:(BOOL)animated
{
    NSLog(@"%s",__func__);
    [super viewWillAppear:animated];    
    recording_ = NO;
}

- (void) viewDidAppear:(BOOL)animated
{
    NSLog(@"%s",__func__);

    UIButton *startStopButton = [UIButton buttonWithType:UIButtonTypeCustom];
    startStopButton.frame = CGRectMake(self.view.center.x, self.view.frame.size.height - 80, 100, 50);
    [startStopButton setTitle:@"record" forState:UIControlStateNormal];
    [startStopButton addTarget:self action:@selector(toggleRecording) forControlEvents:UIControlEventTouchUpInside];
    startStopButton.enabled = YES;
    startStopButton.backgroundColor = [UIColor grayColor];
    [self.view addSubview:startStopButton];


//    [NSTimer timerWithTimeInterval:5 target:self selector:@selector(toggleRecording) userInfo:nil repeats:NO];
    // [NSTimer scheduledTimerWithTimeInterval:5 target:self selector:@selector(endRecording) userInfo:nil repeats:NO];
}

- (void) endRecording
{
    [self dismissModalViewControllerAnimated:YES];
}



//********** CAMERA SET OUTPUT PROPERTIES **********
- (void) CameraSetOutputProperties
{
    //SET THE CONNECTION PROPERTIES (output properties)
    AVCaptureConnection *CaptureConnection = [captureMovieFileOutput_ connectionWithMediaType:AVMediaTypeVideo];

    //Set landscape (if required)
    if ([CaptureConnection isVideoOrientationSupported]){
//        [CaptureConnecti on setVideoOrientation:[UIDevice currentDevice].orientation];

        AVCaptureVideoOrientation orientation = AVCaptureVideoOrientationPortrait;
        [CaptureConnection setVideoOrientation:orientation];
    }

    //Set frame rate (if requried)
    CMTimeShow(CaptureConnection.videoMinFrameDuration);
    CMTimeShow(CaptureConnection.videoMaxFrameDuration);

    if (CaptureConnection.supportsVideoMinFrameDuration)
        CaptureConnection.videoMinFrameDuration = CMTimeMake(1, CAPTURE_FRAMES_PER_SECOND);
    if (CaptureConnection.supportsVideoMaxFrameDuration)
        CaptureConnection.videoMaxFrameDuration = CMTimeMake(1, CAPTURE_FRAMES_PER_SECOND);

    CMTimeShow(CaptureConnection.videoMinFrameDuration);
    CMTimeShow(CaptureConnection.videoMaxFrameDuration);
}

//********** GET CAMERA IN SPECIFIED POSITION IF IT EXISTS **********
- (AVCaptureDevice *) CameraWithPosition:(AVCaptureDevicePosition) Position
{
    NSArray *Devices = [AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo];
    for (AVCaptureDevice *Device in Devices)
    {
        if ([Device position] == Position)
        {
            return Device;
        }
    }
    return nil;
}



//********** CAMERA TOGGLE **********
- (IBAction)CameraToggleButtonPressed:(id)sender
{
    if ([[AVCaptureDevice devicesWithMediaType:AVMediaTypeVideo] count] > 1)        //Only do if device has multiple cameras
    {
        NSLog(@"Toggle camera");
        NSError *error;
        //AVCaptureDeviceInput *videoInput = [self videoInput];
        AVCaptureDeviceInput *NewVideoInput;
        AVCaptureDevicePosition position = [[deviceInput_ device] position];
        if (position == AVCaptureDevicePositionBack)
        {
            NewVideoInput = [[AVCaptureDeviceInput alloc] initWithDevice:[self CameraWithPosition:AVCaptureDevicePositionFront] error:&error];
        }
        else if (position == AVCaptureDevicePositionFront){
            NewVideoInput = [[AVCaptureDeviceInput alloc] initWithDevice:[self CameraWithPosition:AVCaptureDevicePositionBack] error:&error];
        }

        if (NewVideoInput != nil)
        {
            [session_ beginConfiguration];      //We can now change the inputs and output configuration.  Use commitConfiguration to end
            [session_ removeInput:deviceInput_];
            if ([session_ canAddInput:NewVideoInput])
            {
                [session_ addInput:NewVideoInput];
                deviceInput_ = NewVideoInput;
            }
            else
            {
                [session_ addInput:deviceInput_];
            }

            //Set the connection properties again
            [self CameraSetOutputProperties];


            [session_ commitConfiguration];
            [NewVideoInput release];
        }
    }
}




- (void)toggleRecording
{
    NSLog(@"%s",__func__);
    if (!recording_){
        NSLog(@"START RECORDING");
        recording_ = YES;

        NSString* documentsDirectory= [SMFileManager applicationDocumentsDirectory];
        filePathCapturedVideo_ = [documentsDirectory stringByAppendingPathComponent:@"captured-video.mp4"];
        NSLog(@"storing file at %@", filePathCapturedVideo_);
        NSURL *url = [[NSURL alloc] initFileURLWithPath: filePathCapturedVideo_];        
        NSFileManager *fileManager = [NSFileManager defaultManager];
        if ([fileManager fileExistsAtPath:filePathCapturedVideo_]) {
            NSError *error;
            if ([fileManager removeItemAtPath:filePathCapturedVideo_ error:&error] == NO) {
                //Error - handle if requried
            }
        }
        //Start recording
        [captureMovieFileOutput_ startRecordingToOutputFileURL:url recordingDelegate:self];
    } else {
        NSLog(@"STOP RECORDING");
        recording_ = NO;        
        [captureMovieFileOutput_ stopRecording];
    }
}


- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection
{
    NSLog(@"%s",__func__);

}

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

    NSLog(@"%@", outputFileURL);

    NSLog(@"%@", captureOutput);


    NSString* documentsDirectory= [SMFileManager applicationDocumentsDirectory];
    filePathCapturedVideo_ = [documentsDirectory stringByAppendingPathComponent:@"captured-video.mp4"];
    [self.delegate videoCaptured:filePathCapturedVideo_];
}


@end

Answer 1

我遇到过类似的问题，我断定不可能同时使用这两个委托(delegate)。最好的解决方案是只使用 DidOutputSampleBuffer 和 AVAssetWriter 来单独保存文件。