Remove top and bottom gray bar from AVCaptureSession

Question

I am using AVCaptureSession to record video.I want to open camera on full screen but there is gray bar is displaying on top and bottom. I am using following code-

-(void)addCamera
{
    session = [[AVCaptureSession alloc] init];
    session.sessionPreset = AVCaptureSessionPresetMedium;

    AVCaptureVideoPreviewLayer *captureVideoPreviewLayer = [[AVCaptureVideoPreviewLayer alloc] initWithSession:session];
    captureVideoPreviewLayer.frame = self.view.bounds;
    [self.view.layer addSublayer:captureVideoPreviewLayer];

    AVCaptureDevice *device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];

    NSError *error = nil;
    AVCaptureDeviceInput *input = [AVCaptureDeviceInput deviceInputWithDevice:device error:&error];

    AVCaptureDevicePosition currentCameraPosition = [input device].position;
    currentCameraPosition = AVCaptureDevicePositionFront;

    if (!input)
    {
        // Handle the error appropriately.
        NSLog(@"ERROR: trying to open camera: %@", error);
    }
    [session addInput:input];

}

Answer 1

I just change the frame of the captureVideoPreviewLayer and the camera is showing on full screen.