“…Traditional Development [36], [21], [51], [52], [26], [27], [54], [12], [56], [44], [45], 15 [63], [64], [33], [59] 5 Additional [20], [13], [25], [50], [37], [22], [57], [28], [14], [29], [30], 17 [58], [19], [65], [15], [34], [60] [49], [38], [61], [55] 2 Face Recognition Techniques / Algorithms [13], [25], [50], [28] 3 Head Pose Estimation and Detection Techniques [11], [57], [35] 4 Natural Language Processing (NLP) Based Techniques [62], [53], [32] 5 Genetic Algorithms [43], [63], …”