Table 2.

Micro-expression facial datasets.

Database	Characteristics	Images	Subjects	Facial Expression	References
SMIC [87]	spontaneous	164	6	77 micro-expressions	[64,84,88,89,90]
CASME II [91]	spontaneous	247	26	happiness, disgust, surprise, repression, and others	[64,84,88,89,90,92,93]
SAMM [94]	spontaneous	159	32	contempt, disgust, fear, anger, sadness, happiness, surprise	[64,89,90,92]