Real-time adaptive skin detection using skin color model updating unit in videos

Skin color plays an important role in color image processing and human-computer interaction. However, factors such as rapidly changing illumination, various color styles, and camera characteristics also make skin detection a challenging task. In particular, the real-time requirement of practical applications is a challenging task in skin detection. In this paper, face detection and alignment are applied to select facial reference points for modeling the skin color distribution. Moreover, we propose the conception and detection approach of skin color model updating unit (SCMUU) according to the fact of skin color distribution remains consistent in a range of frames. The redundant operation of frame by frame updating is avoided using one model in frames of SCMUU. When no reliable faces are detected, two strategies are introduced to remedy and reduce the computational cost. It uses the corresponding model parameters if a similar previous SCMUU is found. Otherwise, we use fixed thresholds instead and increase the interval between two consecutive face detection. Besides, the time-consuming steps are accelerated using a graphic processing unit (GPU) with CUDA in this paper. Experimental results show that, compared with other existing methods, the proposed method has good real time and accuracy for skin detection of various resolution videos under different illumination conditions.