Building Computer Vision Projects with OpenCV 4 and C++

Detection mode

In the Detection mode, we want to continuously detect faces and eyes, draw rectangles or circles around them to show the detection result, and show the current preprocessed face. In fact, we will want these to be displayed no matter which mode we are in. The only thing special about the Detection mode is that it will change to the next mode (Collection) when the user clicks the Add Person button.

If you remember from the detection step, in this chapter, the output of our detection stage will be as follows:

• Mat preprocessedFace: The preprocessed face (if face and eyes were detected)
• Rect faceRect: The detected face region coordinates
• Point leftEye, rightEye: The detected left and right eye center coordinates

So, we should ...