Mastering OpenCV 3 - Second Edition

Viewing the learned knowledge

While it is not necessary, it is quite useful to view the internal data structures that the face-recognition algorithm generated when learning your training data, particularly if you understand the theory behind the algorithm you selected and want to verify if it worked or find out why it is not working as you hoped. The internal data structures can be different for different algorithms, but luckily they are the same for eigenfaces and fisherfaces, so let's just look at those two. They are both based on 1D eigenvector matrices that appear somewhat like faces when viewed as 2D images, therefore it is common to refer as eigenvectors as eigenfaces when using the Eigenface algorithm or as fisherfaces when using the ...