如何在使用emgucv检测人脸和嘴巴后确定人脸特征

我正在用c#进行情感检测,为此,我使用emgucv和haarcascades xml检测人脸、嘴巴和眼睛,现在我使用这段代码来确定检测人脸上的情感是什么

var faces = grayframe.DetectHaarCascade(
                        haar, 1.4, 4,
                        HAAR_DETECTION_TYPE.DO_CANNY_PRUNING,
                        new Size(nextFrame.Width / 8, nextFrame.Height / 8)
                        )[0];
  foreach (var f in faces)
  {    
  image.Draw(f.rect, new Bgr(Color.Blue), 2);    
    gray.ROI = f.rect;
 var mouthsDetected = gray.DetectHaarCascade(mouth, 
                          1.1, 10, 
                          Emgu.CV.CvEnum.HAAR_DETECTION_TYPE.DO_CANNY_PRUNING, 
                          new Size(20, 20));
 gray.ROI = Rectangle.Empty;


 foreach (var m in mouthsDetected [0])
 {
      Rectangle mouthRect = m.rect;
      mouthRect.Offset(f.rect.X, f.rect.Y);
      image.Draw(mouthRect , new Bgr(Color.Red), 2);
 }

}

我从中找到此代码 here