FACE DETECTION

Video face detection apparatus in which a test image from a video sequence is compared with an image property model derived from image properties of a region detected to contain a face in a preceding image in the video sequence comprises: selecting a predetermined proportion of pixels in the region detected to contain a face in the preceding image which most closely match the image property model derived in respect of that region, thereby deriving a pixel mask; and comparing pixels in the test image defined by the pixel mask with the image property model, the mask being applied at more than one image position within the test image; a face being detected in the test image at a mask position corresponding to a lowest average difference between the image property model and pixels defined by the mask at that position.