Algorithm 2: Texture Feature Extraction Algorithm
	Input: videos from HC or PD, number of videos N,
	Output: texture feature vectors for each video
1	for n = 1: N do
2	read n-th video → Video
3	while getFrame(Video) == True do
4	face detection
5	face alignment
6	crop face picture and resize to 128*128
7	get three-dimensional arrays for each video
8	compute HOG-XY, HOG-XT, HOG-YT from XY, XT and YT plane
9	concatenate three features
10	get feature vectors for each video