In terms of speed, HoG seems to be the fastest algorithm, followed by Haar Cascade classifier and CNNs . However, CNNs in Dlib tend to be the most accurate algorithm. HoG perform pretty well but have some issues identifying small faces. HaarCascade Classifiers perform around as good as HoG overall.
Read moreWhat kind of learning algorithm is required for facial recognition?
Facial detection via the Viola-Jones algorithm is a com- mon method used due to its high detection rate and fast pro- cessing speed. The algorithm can be summed up in four steps: feature selection, feature evaluation, feature learning to create a classifier, and cascading classifiers.
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