A face feature analysis which begins by generating multiple face feature candidates, e.g., eyes and
nose positions, using an isolated frame
face analysis. Then, a
nostril tracking window is defined around a
nose candidate and tests are applied to the pixels therein based on percentages of
skin color area pixels and
nostril area pixels to determine whether the
nose candidate represents an actual nose. Once actual nostrils are identified, size, separation and
contiguity of the actual nostrils is determined by projecting the
nostril pixels within the nostril tracking window. A mouth window is defined around the
mouth region and mouth detail analysis is then applied to the pixels within the mouth window to identify inner mouth and teeth pixels and therefrom generate an inner mouth contour. The nostril position and inner mouth contour are used to generate a synthetic model head. A direct comparison is made between the inner mouth contour generated and that of a synthetic model head and the synthetic model head is adjusted accordingly.
Vector quantization algorithms may be used to develop a
codebook of
face model parameters to improve
processing efficiency. The face feature analysis is suitable regardless of
noise, illumination variations,
head tilt, scale variations and nostril shape.