Head pose estimation using both color and feature information
Chen Qian, Haiyuan Wu, S. Shioyama, T. Shimada · 2002
Describes a method to estimate the three-dimensional pose of a human head in a single image. An efficient method based on a perceptually uniform color system and fuzzy theory is used to extract the skin region and the hair region from an image, which are then used to detect the face and to estimate the approximate pose of it. The viewable facial features and the positions of them are then predicted with the head pose. The facial features are detected within the predicted region, which are then used to estimate the 3D pose of the head.