I am using LBPHFaceRecognizer algorithm,and using following code :-- mJavaDetector.detectMultiScale(mGray, faces, 1.3, 2, Objdetect.CASCADE_FIND_BIGGEST_OBJECT, new Size(mAbsoluteFaceSize, mAbsoluteFaceSize), new Size()); . So which would be the best scenario for recognizing the images in OpenCv 4.1.0