Automatic detection of facial midline as a guide for facial feature extraction

We propose a novel approach for the detection of the facial midline from a frontal face image. The use of a midline as a guide reduces the computation time required for facial feature extraction (FFE) because midline is able to restrict multi-dimensional searching process into one-dimensional search. The proposed method detects facial midline from the edge image as the symmetry axis using a new application of the the generalized Hough transformation to detect the symmetry axis. Experimental results on the FERET database indicate that the proposed algorithm can accurately detect facial midline over many different scales and rotation. The total computational time for facial feature extraction has been reduced by a factor of 280 using midline detected by this method.