使用 UIImagePickerController 偷偷录制电影答案

【问题标题】：Secretly record a movie using UIImagePickerController使用 UIImagePickerController 偷偷录制电影
【发布时间】：2012-08-16 13:30:40
【问题描述】：

我正在为 iPhone 4/4S 制作密码应用程序。当用户输入密码 3 次失败时，我想使用 iPhone 的前置摄像头制作用户的电影。这并不是什么新鲜事，应用商店中的许多应用都在做类似的事情。给这个人拍照，获取他的 GEO 坐标等。

我面临的挑战是，当我尝试设置电影录制时，相机覆盖会占据整个屏幕。我真正想做的是让用户仍然看到登录屏幕和按钮，但偷偷录制并制作用户的电影。有没有办法我可以做到这一点？

这是我正在使用的代码。

在我的 *.h 文件中

@interface v1InstantController : UIViewController <UIImagePickerControllerDelegate>
{   
    UIImagePickerController *picpicker;
}

@property (nonatomic, retain) UIImagePickerController *picpicker;

在我的 *.m 文件中

-(IBAction) makeMovieNow
{
    picpicker = [[UIImagePickerController alloc] init];
        picpicker.delegate = self;


        picpicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
        picpicker.sourceType = UIImagePickerControllerSourceTypeCamera;

        picpicker.showsCameraControls = NO;
        picpicker.navigationBarHidden = YES;
        picpicker.wantsFullScreenLayout = NO;

        picpicker.mediaTypes = [NSArray arrayWithObject:(NSString *)kUTTypeMovie];
        picpicker.cameraCaptureMode = UIImagePickerControllerCameraCaptureModeVideo;

        picpicker.cameraFlashMode = UIImagePickerControllerCameraFlashModeOff;
        picpicker.cameraDevice = UIImagePickerControllerCameraDeviceFront;

        picpicker.videoQuality = UIImagePickerControllerQualityTypeHigh;

        picpicker.mediaTypes = [UIImagePickerController availableMediaTypesForSourceType:UIImagePickerControllerSourceTypeCamera];

        //The problem is right here! 
        //picpicker.cameraViewTransform = CGAffineTransformScale(picpicker.cameraViewTransform, 0.01, 0.01);
        [self presentModalViewController:picpicker animated:YES];

        [picpicker startVideoCapture];
}

问题就在这里“presentModalViewController:picpicker”。当我使用它时，它会启动带有虹膜飞溅等的相机屏幕，并显示整个屏幕上正在记录的内容。即使我使用 cameraViewTransform，它仍然会禁用页面上的任何内容并将此相机叠加层放在页面中间。（有一个非常小的相机覆盖）我不希望用户知道我正在录制并且希望他认为它照常营业。即让他继续尝试在页面上输入密码失败。

【问题讨论】：

标签： iphone ios xcode xcode4 uiimagepickercontroller

【解决方案1】：

UIImagePickerController 提供了一种从用户那里轻松获取照片/视频的方法，因此用户始终可以看到它。

由于您似乎需要更多控制权，您可以查看 AVFoundation。 Apple Documentation 应该提供一个很好的起点。

【讨论】：

有几个示例项目可用：AVCam 用于基础知识，SquareCam 也可能很有趣。

【解决方案2】：

这里是任何可能对未来感兴趣的人的答案。给它评分！

确保包含 coreVideo 和 CoreMedia 框架

在您的 *.h 文件中

@interface v1InstantController : UIViewController <UIImagePickerControllerDelegate,UINavigationControllerDelegate>
{
    AVCaptureSession *session;
    NSString *videoPath2;
}

@property (nonatomic, retain) AVCaptureSession *session;
@property (nonatomic, retain) NSString *videoPath2;

在您的 *.m 文件中

@synthesize session;
@synthesize videoPath2;

-(IBAction) makeMovieNow
{

    NSLog(@"makeMovieNow ..");

    //record movie
    session = [[AVCaptureSession alloc] init];
    [session beginConfiguration];
    session.sessionPreset = AVCaptureSessionPresetHigh;

    AVCaptureVideoPreviewLayer *captureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session];
    captureVideoPreviewLayer.videoGravity = AVLayerVideoGravityResizeAspectFill;


    NSError *error = nil;
    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    device = [self frontFacingCameraIfAvailable];
    AVCaptureDeviceInput *videoInput = [AVCaptureDeviceInput deviceInputWithDevice:device error:&error];
    if (!videoInput) 
    {
        // Handle the error appropriately.
        NSLog(@"ERROR: trying to open camera: %@", error);
    }

    AVCaptureDevice *audioDevice     = [AVCaptureDevice defaultDeviceWithMediaType: AVMediaTypeAudio];
    AVCaptureDeviceInput *audioInput = [AVCaptureDeviceInput deviceInputWithDevice:audioDevice error:&error ]; 


    AVCaptureMovieFileOutput *movieFileOutput = [[AVCaptureMovieFileOutput alloc] init];

    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectoryPath = [paths objectAtIndex:0];
    NSString *movieFileName = [NSString stringWithFormat: @"Secret.mov"];
    NSString *fullPathToFile2 = [documentsDirectoryPath stringByAppendingPathComponent:movieFileName];
    NSURL *outputURL = [[NSURL alloc] initFileURLWithPath:fullPathToFile2];

    videoPath2=[outputURL path];


    [session addInput:videoInput];
    [session addInput:audioInput];
    [session addOutput:movieFileOutput];
    [session commitConfiguration];

    //start recording
    [session startRunning];
    [movieFileOutput startRecordingToOutputFileURL:outputURL recordingDelegate:self];
}

-(IBAction) makeMovieStop
{
    NSLog(@"makeMovieStop ...");

    //stop recording
    [session stopRunning];

    //save video to photo-album
    UISaveVideoAtPathToSavedPhotosAlbum(videoPath2, self, nil, nil);

}

【讨论】：