// 目の検出範囲を顔の上3/5の領域に制限する
Rect faceUpper = faces[f];
faceUpper.height = faceUpper.height * 3 / 5;
Mat faceGray = gray(faceUpper);
// 目の検出
vector<Rect> eyes;
eye_cascade.detectMultiScale(faceGray, eyes, 1.1, 3, 0, Size(5, 5));

