Patent ID: 7773781

Claim:
A face detection method, comprising: determining whether a face is detected in a previous frame image; if the face is not detected in the previous frame image, detecting the face in a first image according to one detection mode selected from N face detection modes, where N is an integer equal to or greater than 2; and if the face is detected in the previous frame image, detecting the face by performing sequentially at least one tracking mode of N face tracking modes with a second image, wherein the face detection modes comprise a frontal face detection mode, a right-rotated face detection mode, and a left-rotated face detection mode, the face tracking modes comprise a frontal face tracking mode, a right-rotated face tracking mode, and a left-rotated face tracking mode, and detecting the face in the first image comprises dividing a number of previous frames in which the face is not detected by N and selecting one among the N face detection modes according to a remainder of the dividing and performing face detection according to the selected face detection mode.