AVFoundationでカメラを表示するとても短いサンプル

#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>

@interface ViewController : UIViewController<AVCaptureVideoDataOutputSampleBufferDelegate>
@property (nonatomic, strong) AVCaptureSession* session;
@property (nonatomic, strong) IBOutlet UIImageView* imageView;
@end

- (void)viewDidLoad
{
    [super viewDidLoad];
    //デバイス取得
    AVCaptureDevice* device = [AVCaptureDevice defaultDeviceWithMediaType:AVMediaTypeVideo];
    //入力作成
    AVCaptureDeviceInput* deviceInput = [AVCaptureDeviceInput deviceInputWithDevice:device error:NULL];

    //ビデオデータ出力作成
    NSDictionary* settings = @{(id)kCVPixelBufferPixelFormatTypeKey:[NSNumber numberWithInt:kCVPixelFormatType_32BGRA]};
    AVCaptureVideoDataOutput* dataOutput = [[AVCaptureVideoDataOutput alloc] init];
    dataOutput.videoSettings = settings;
    [dataOutput setSampleBufferDelegate:self queue:dispatch_get_main_queue()];

    //セッション作成
    self.session = [[AVCaptureSession alloc] init];
    [self.session addInput:deviceInput];
    [self.session addOutput:dataOutput];
    self.session.sessionPreset = AVCaptureSessionPresetHigh;

    AVCaptureConnection *videoConnection = NULL;

    // カメラの向きなどを設定する
    [self.session beginConfiguration];

    for ( AVCaptureConnection *connection in [dataOutput connections] )
    {
        for ( AVCaptureInputPort *port in [connection inputPorts] )
        {
            if ( [[port mediaType] isEqual:AVMediaTypeVideo] )
            {
                videoConnection = connection;

            }
        }
    }
    if([videoConnection isVideoOrientationSupported]) // **Here it is, its always false**
    {
        [videoConnection setVideoOrientation:AVCaptureVideoOrientationPortrait];
    }

    [self.session commitConfiguration];
    // セッションをスタートする
    [self.session startRunning];
}

//delegateメソッド。各フレームにおける処理
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection
{
    // 画像の表示
    self.imageView.image = [self imageFromSampleBufferRef:sampleBuffer];
}

// CMSampleBufferRefをUIImageへ
- (UIImage *)imageFromSampleBufferRef:(CMSampleBufferRef)sampleBuffer
{
    // イメージバッファの取得
    CVImageBufferRef    buffer;
    buffer = CMSampleBufferGetImageBuffer(sampleBuffer);

    // イメージバッファのロック
    CVPixelBufferLockBaseAddress(buffer, 0);
    // イメージバッファ情報の取得
    uint8_t*    base;
    size_t      width, height, bytesPerRow;
    base = CVPixelBufferGetBaseAddress(buffer);
    width = CVPixelBufferGetWidth(buffer);
    height = CVPixelBufferGetHeight(buffer);
    bytesPerRow = CVPixelBufferGetBytesPerRow(buffer);

    // ビットマップコンテキストの作成
    CGColorSpaceRef colorSpace;
    CGContextRef    cgContext;
    colorSpace = CGColorSpaceCreateDeviceRGB();
    cgContext = CGBitmapContextCreate(
                                      base, width, height, 8, bytesPerRow, colorSpace,
                                      kCGBitmapByteOrder32Little | kCGImageAlphaPremultipliedFirst);
    CGColorSpaceRelease(colorSpace);

    // 画像の作成
    CGImageRef  cgImage;
    UIImage*    image;
    cgImage = CGBitmapContextCreateImage(cgContext);
    image = [UIImage imageWithCGImage:cgImage scale:1.0f
                          orientation:UIImageOrientationUp];
    CGImageRelease(cgImage);
    CGContextRelease(cgContext);

    // イメージバッファのアンロック
    CVPixelBufferUnlockBaseAddress(buffer, 0);
    return image;
}