ios - 像素格式：kCVPixelFormatType_32BGRA 与 AVVideoCodecJPEG

Question

我试图找出哪个更好地捕捉JPEG

AVFoundation -> PhotoCaptureDelegate

我可以用：

photoSettings = AVCapturePhotoSettings(format: [ kCVPixelBufferPixelFormatTypeKey as String: Int(kCVPixelFormatType_32BGRA) ])

或者

photoSettings = AVCapturePhotoSettings(format: [AVVideoCodecKey : AVVideoCodecJPEG, AVVideoCompressionPropertiesKey : [AVVideoQualityKey : 1.0]] as [String : Any])

我注意到使用AVVideoCodecJPEG，我可以使用压缩质量；但是，如果我正在PhotoCaptureDelegate中的CMSampleBuffer执行任何 TIFF 转换或其他任务，我将无法使用。

然而，如果我只想以新的方式保存到 JPEG（猜测最有效的方式，我必须使用AVVideoCodecJPEG来做：

func capture(_ captureOutput: AVCapturePhotoOutput, didFinishProcessingPhotoSampleBuffer photoSampleBuffer: CMSampleBuffer?, previewPhotoSampleBuffer: CMSampleBuffer?, resolvedSettings: AVCaptureResolvedPhotoSettings, bracketSettings: AVCaptureBracketedStillImageSettings?, error: Error?) {

    self.jpegPhotoData = AVCapturePhotoOutput.jpegPhotoDataRepresentation(forJPEGSampleBuffer: photoSampleBuffer, previewPhotoSampleBuffer: previewPhotoSampleBuffer)

    }

哪个更好用？