captureOutput 中的 iOS 应用相机方向

Question

首先，我知道很多人问过类似的问题 - 但我找不到任何类似的问题。

调用该接口(interface)时:

- (void) captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection
{

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

    // get buffer dimensions
    size_t bufferHeight = CVPixelBufferGetHeight(pixelBuffer);
    size_t bufferWidth  = CVPixelBufferGetWidth(pixelBuffer);
...

当手机处于“纵向模式”时 - 我得到的高度为480，宽度为640。奇怪的是，当我检查 [connection videoOrientation] 时，它被正确设置为纵向。

1. 为什么连接方向不影响采样缓冲区？
2. 我应该自己旋转图像吗？
3. 有没有办法将样本配置为由设备方向给出？

谢谢

---

@加布里埃尔:我已经有了这个代码:

-(void) viewWillLayoutSubviews
{
    // Handle camera
    if (_videoPreviewLayer)
    {
        _videoPreviewLayer.frame = self.view.bounds;

        for (AVCaptureOutput* outcap in _captureSession.outputs)
        {
            for(AVCaptureConnection* con in outcap.connections)
            {
                switch ([[UIDevice currentDevice] orientation])
                {

                    case UIInterfaceOrientationPortrait:
                        [con setVideoOrientation:AVCaptureVideoOrientationPortrait];

                        break;
                    case UIInterfaceOrientationLandscapeRight:
                        [con setVideoOrientation:AVCaptureVideoOrientationLandscapeRight]; //home button on right. Refer to .h not doc
                        break;
                    case UIInterfaceOrientationLandscapeLeft:
                        [con setVideoOrientation:AVCaptureVideoOrientationLandscapeLeft]; //home button on left. Refer to .h not doc
                        break;
                    case UIInterfaceOrientationPortraitUpsideDown:
                        [con setVideoOrientation:AVCaptureVideoOrientationPortraitUpsideDown]; //home button on left. Refer to .h not doc
                        break;
                    default:
                        [con setVideoOrientation:AVCaptureVideoOrientationPortrait]; //for portrait upside down. Refer to .h not doc
                        break;
                }
            }
        }
    }
}

正如我上面提到的，在检查连接时 - 它是正确的方向，尽管图像是错误的方向..

您是否通过手动修复它来引用 - 使用什么方法自动更改为正确的方向？

关键是显示效果不错，只是拍照...

Answer 1

解决您的问题:

1 - 检查您是否禁用或修改了方向模式。

2 - 使用 AVFoundation 时，您必须自己旋转图像，这是我使用的代码:

AVCaptureVideoOrientation newOrientation;
switch ([[UIDevice currentDevice] orientation]) {
            case UIDeviceOrientationPortrait:
                newOrientation = AVCaptureVideoOrientationPortrait;
                break;
            case UIDeviceOrientationPortraitUpsideDown:
                newOrientation = AVCaptureVideoOrientationPortraitUpsideDown;
                break;
            case UIDeviceOrientationLandscapeLeft:
                newOrientation = AVCaptureVideoOrientationLandscapeRight;
                break;
            case UIDeviceOrientationLandscapeRight:
                newOrientation = AVCaptureVideoOrientationLandscapeLeft;
                break;
            default:
                newOrientation = AVCaptureVideoOrientationPortrait;
        }

3 - 使用上面的代码

希望这对您有所帮助。