CtsVideoCallView.swift

// MARK: - AVCaptureVideoDataOutputSampleBufferDelegate extension {{{
extension CtsVideoCallView: AVCaptureVideoDataOutputSampleBufferDelegate {
  func captureOutput(_ captureOutput: AVCaptureOutput!,
      didOutputSampleBuffer sampleBuffer: CMSampleBuffer!,
      from: AVCaptureConnection!) {
    // get image size for preview and resize preview view accordingly
    let imageBuffer = CMSampleBufferGetImageBuffer(sampleBuffer)
    let attachments = CMCopyDictionaryOfAttachments(kCFAllocatorDefault,
        sampleBuffer, kCMAttachmentMode_ShouldPropagate) as! Dictionary
    let ciImage = CIImage(cvPixelBuffer: imageBuffer, options: attachments)

    let height = ciImage.cgImage.height
    let width = ciImage.cgImage.width

    let localVideoSize = CGSize(width: width, height: height)
    self.localVideoView.frame.size = localVideoSize
  }
}
// }}} AVCaptureVideoDataOutputSampleBufferDelegate extension