标签: avcapturesession

我正在使用Apple的AVCaptureSession示例代码,并且创建的UIImage完全空白.这只发生在iPhone 3G上,还有一个独特的错误显示在控制台上,上面写着 -

错误:CGDataProviderCreateWithCopyOfData:vm_copy失败:状态2.

我已经在线研究了错误,发现了这个StackOverflow的答案,它摆脱了错误......但是图像仍然是空白的.

有没有其他人经历过这个并知道如何修复它？

提前致谢.

我的代码 -

CVImageBufferRef imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer); 
CVPixelBufferLockBaseAddress(imageBuffer, 0); 

void *baseAddress = CVPixelBufferGetBaseAddress(imageBuffer); 
size_t bytesPerRow = CVPixelBufferGetBytesPerRow(imageBuffer); 
size_t width = CVPixelBufferGetWidth(imageBuffer); 
size_t height = CVPixelBufferGetHeight(imageBuffer); 

CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); 

CGContextRef context = CGBitmapContextCreate(baseAddress, width, height, 8, bytesPerRow, colorSpace, kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst); 
CGImageRef quartzImage = CGBitmapContextCreateImage(context); 
CVPixelBufferUnlockBaseAddress(imageBuffer,0);

CGContextRelease(context); 
CGColorSpaceRelease(colorSpace);

UIImage *image = [UIImage imageWithCGImage:quartzImage];

CGImageRelease(quartzImage);

return image;

我使用ZXing作为应用程序,这主要是与ZXing原始代码相同的代码,除了我允许连续扫描几次(即,一旦检测到某些东西,ZXingWidgetController就不会被解雇).

当我按下调用的关闭按钮时,我会经历长时间的长时间冻结(有时它永远不会结束)

- (void)cancelled {
  //  if (!self.isStatusBarHidden) {
  //      [[UIApplication sharedApplication] setStatusBarHidden:NO];
  //  }

    [self stopCapture];

    wasCancelled = YES;
    if (delegate != nil) {
        [delegate zxingControllerDidCancel:self];
    }


} 

同

- (void)stopCapture {
    decoding = NO;
#if HAS_AVFF


    if([captureSession isRunning])[captureSession stopRunning];
    AVCaptureInput* input = [captureSession.inputs objectAtIndex:0];
    [captureSession removeInput:input];
    AVCaptureVideoDataOutput* output = (AVCaptureVideoDataOutput*)[captureSession.outputs objectAtIndex:0];
    [captureSession removeOutput:output];
    [self.prevLayer removeFromSuperlayer];

    /*
     // heebee jeebees here ... is iOS still writing into the layer?
     if (self.prevLayer) {
     layer.session = nil;
     AVCaptureVideoPreviewLayer* layer = prevLayer; …

iOS-app最小化时如何从相机拍照？
(即applicationDidEnterBackground:/ 之后applicationWillResignActive:)

AppDelegate.m: (感谢你链接)

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{

    //To make the code block asynchronous
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{

        //### background task starts
        NSLog(@"Running in the background\n");
        while(TRUE)
        {
            printf("Called"); //////Work fine

            [self.window.rootViewController captureNow]; /////Capture picture!

            [NSThread sleepForTimeInterval: 10.0]; //wait for 10 sec
        }
    });

    return YES;
}

OurViewController.m: (感谢你链接)

-(IBAction)captureNow {

    AVCaptureConnection *videoConnection = nil;
    for (AVCaptureConnection *connection in _stillImageOutput.connections)
    {
        for (AVCaptureInputPort *port in [connection inputPorts])
        {
            if ([[port …

我使用AVCaptureSession拍照并将照片存储到相册.当我点击按钮时,它会拍摄快照并存储到相册.但是当我使用横向模式时,然后单击它存储横向模式的按钮会导致倒置静止图像.

码:

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view.

    [self setCaptureSession:[[AVCaptureSession alloc] init]];


    [self  addVideoInputFrontCamera:NO]; // set to YES for Front Camera, No for Back camera

    [self  addStillImageOutput];

    [self setPreviewLayer:[[AVCaptureVideoPreviewLayer alloc] initWithSession:[self captureSession]] ];

      [[self previewLayer] setVideoGravity:AVLayerVideoGravityResizeAspectFill];

      CGRect layerRect = [[[self view] layer] bounds];


    [[self previewLayer]setBounds:layerRect];
    [[self  previewLayer] setPosition:CGPointMake(CGRectGetMidX(layerRect),CGRectGetMidY(layerRect))];
    [[[self view] layer] addSublayer:[self  previewLayer]];

     [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(saveImageToPhotoAlbum) name:kImageCapturedSuccessfully object:nil];


    [[self captureSession] startRunning];

camera=[UIButton buttonWithType:UIButtonTypeCustom];
[camera setImage:[UIImage imageNamed:@"button.png"] forState:UIControlStateNormal];
[camera setFrame:CGRectMake(150, 10, 40, …

我试图在iOS上在GPUImage上实现视频录制.

我有一个GPUImageVideoCamera,我正在尝试设置这样的录音:

-(void)toggleVideoRecording {
if (!self.recording) {
    self.recording = true;
    GPUImageMovieWriter * mw = [self createMovieWriter: self.filter1];

    [self.filter1 addTarget:mw];
    mw.shouldPassthroughAudio = YES;
    [mw startRecording];
}
else {
    self.recording = false;
    [self finishWritingMovie];
}

}

-(GPUImageMovieWriter *) createMovieWriter:(GPUImageFilter *) forFilter {
    NSString *pathToMovie = [NSHomeDirectory() stringByAppendingPathComponent:@"Documents/CurrentMovie.m4v"];
    unlink([pathToMovie UTF8String]);
    NSURL *movieURL = [NSURL fileURLWithPath:pathToMovie];

    GPUImageMovieWriter * mw = [[GPUImageMovieWriter alloc] initWithMovieURL:movieURL size:forFilter->currentFilterSize];
    self.movieWriter = mw;
    self.movieURL = movieURL;

    return mw;
}

这实际上大部分都有效 但是,MoviewWriter需要输入媒体的CGSize,我不知道如何将它从VideoCamera中拉出来.首先,尺寸会有所不同,因为相机正在使用sessionPreset:AVCaptureSessionPresetHigh,这意味着它会根据设备的功能而变化.其次,方向改变了相关的CGSize.如果用户以横向模式开始录制,我想转置尺寸.

对于任何知道如何使用vanilla CoreVideo执行此操作的人,我可以将AVCaptureSession从我的GPUImageVideoCamera中拉出来.(但我已经阅读了AVCaptureSession的API,没有什么看起来很有希望).

甚至将我引用到处理此项目的示例项目也会非常有帮助.

我正在使用AvCapture会话在相机屏幕上添加cutom叠加.我添加了一个AvCaptureVidePreview图层

AvCaptureVideoPreviewLayer*layer = [[AvCaptureVideoPreviewLayer alloc] iniWithSession:session];
layer.frame = self.view.layer.bounds;

但在iPhone 4S的情况下,相机预览不是全屏.它在iPhone 5中运行良好.

我正在尝试捕捉图像:

var stillImageOutput = AVCaptureStillImageOutput()
stillImageOutput!.outputSettings = [AVVideoCodecKey: AVVideoCodecJPEG]

[...] 

if let videoConnection = stillImageOutput.connectionWithMediaType(AVMediaTypeVideo) {
     videoConnection.videoOrientation = AVCaptureVideoOrientation.Portrait
     println("enabled = \(videoConnection.enabled)") //enabled = true
     println("active = \(videoConnection.active)") //active = true
     stillImageOutput.captureStillImageAsynchronouslyFromConnection(videoConnection, completionHandler: {
          (sampleBuffer, error) in
          if error != nil {
               println(error)
          }
     })
}

它大多数时候都很完美!

但有时我在调用时遇到错误captureStillImageAsynchronouslyFromConnection:

Error Domain=AVFoundationErrorDomain Code=-11800 "The operation couldn't be completed." 
UserInfo=0x14682110 {NSLocalizedDescription=The operation couldn't be completed., 
NSUnderlyingError=0x1676be30 "The operation couldn't be completed.
(OSStatus error -16400.)", 
NSLocalizedFailureReason=An unknown error has occured (-16400)}

我只是想预料会发生这个错误.我尝试过测试 …

我正在尝试构建一个应用程序,它将从相机捕获帧并使用OpenCV处理它们,然后将这些文件保存到设备,但是以特定的帧速率.

我现在坚持的是这个事实AVCaptureVideoDataOutputSampleBufferDelegate似乎并不尊重AVCaptureDevice.activeVideoMinFrameDuration或AVCaptureDevice.activeVideoMaxFrameDuration设置.

captureOutput 如上面的设置所示,运行速度远远超过每秒2帧.

你是否碰巧知道无论是否有代表,人们都能做到这一点？

视图控制器:

override func viewDidLoad() {
    super.viewDidLoad()

}

override func viewDidAppear(animated: Bool) {
    setupCaptureSession()
}

func setupCaptureSession() {

    let session : AVCaptureSession = AVCaptureSession()
    session.sessionPreset = AVCaptureSessionPreset1280x720

    let videoDevices : [AVCaptureDevice] = AVCaptureDevice.devices() as! [AVCaptureDevice]

    for device in videoDevices {
        if device.position == AVCaptureDevicePosition.Back {
            let captureDevice : AVCaptureDevice = device

            do {
                try captureDevice.lockForConfiguration()
                captureDevice.activeVideoMinFrameDuration = CMTimeMake(1, 2)
                captureDevice.activeVideoMaxFrameDuration = CMTimeMake(1, 2)
                captureDevice.unlockForConfiguration()

                let input : AVCaptureDeviceInput = try …

我正在实施水龙头以集中精力，并为如何使用不同而感到困惑AVCaptureFocusModes。这样做：

[device setFocusPointOfInterest:focusPoint];
[device setFocusMode:AVCaptureFocusModeAutoFocus];

可以成功对焦，但是由于锁定焦距，移动相机将永远失去对焦。相反，如果我这样做：

[device setFocusPointOfInterest:focusPoint];
[device setFocusMode:AVCaptureFocusModeContinousAutoFocus];

自动对焦引擎似乎消除了我的兴趣，只专注于看起来最好的东西。相机应用程序成功聚焦在您的兴趣点上，同时在移动相机时也保持连续自动对焦，这是怎么做的？

到目前为止，这是我的完整代码：

- (void)setFocusPointOfInterest:(CGPoint)point
{
    Class captureDeviceClass = NSClassFromString(@"AVCaptureDevice");
    if (captureDeviceClass != nil) {
        AVCaptureDevice *device = [captureDeviceClass defaultDeviceWithMediaType:AVMediaTypeVideo];
        if([device isFocusPointOfInterestSupported] &&
           [device isFocusModeSupported:AVCaptureFocusModeAutoFocus]) {
            CGRect screenRect = [[UIScreen mainScreen] bounds];
            double screenWidth = screenRect.size.width;
            double screenHeight = screenRect.size.height;
            double focus_x = point.x/screenWidth;
            double focus_y = point.y/screenHeight;
            CGPoint focusPoint = CGPointMake(focus_x,focus_y);
            if([device lockForConfiguration:nil]) {
                [device setFocusPointOfInterest:focusPoint];
                [device setFocusMode:AVCaptureFocusModeAutoFocus];
                [device setExposurePointOfInterest:focusPoint];
                if ([device isExposureModeSupported:AVCaptureExposureModeAutoExpose]){
                    [device setExposureMode:AVCaptureExposureModeAutoExpose];
                }
                [device unlockForConfiguration]; …

我正在玩swift和iPhone 7 Plus.我正在使用builtInWideAngleCamera和builtInTelephotoCamera.即使我无法同时获得2张图像,这也很棒.

我在Apple文档中看到AVCaptureDeviceType包含一个builtInDualCamera条目.这个设备在avfoundation中的目的是什么,因为我们不能用apple API做任何事情(缩放,深度效果)？

换句话说,在使用AVCaptureDeviceType,avcapturesession和stuff时,我看不出builtInDualCamera和builtInWideAngleCamera之间的区别

谢谢