Face-image processing apparatus

• US 6,718,050 B1
• Filed: 11/19/1999
• Issued: 04/06/2004
• Est. Priority Date: 05/24/1999
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Yamamoto, Takayuki
• Primary Examiner(s): Au, Amelia M.
• Assistant Examiner(s): LAROSE, COLIN M
• Application Number:
  US09/444,577
• Time in Patent Office: 1,600 Days
• Field of Search: 382/117, 382/118, 382/103, 382/171, 382/173, 382/203, 348/78
• US Class Current: 382/117
• CPC Class Codes: G06V 40/167 using comparisons between temporally consecutive images
• CPC Class Codes: G06V 40/193 Preprocessing; Feature extraction

Abstract

A multivalue image of the face input by a CCD camera 2 is stored in a multivalue-image memory 3. A multivalue-image characteristic extracting means 23 extracts a pixel of interest from the stored multivalue face image in accordance with distribution of relative brightness of the brightness of the pixel of interest and those of pixels adjacent to the pixel of interest. The extracted pixel of interest is stored in a binarized-image memory 5. The stored pixel of interest is used to extract an eye region. In accordance with the extracted eye region, an opening/closing determining means 7 determines opening/closing of the eyes.

Claims

1. A face-image processing apparatus comprising:

image input means for inputting a multivalue face image that expresses a brightness of a pixel disposed in a matrix configuration by multivalue;

multivalue-image characteristic extracting means for extracting an eye region from the multivalue face image input by said image input means; and

opening/closing determining means for determining opening/closing of the eyes in accordance with the eye region extracted by said multivalue-image characteristic extracting means, wherein

said multivalue-image characteristic extracting means extracts the eye region by a one-dimensional filter process,

wherein the limits of an object range are set to the front of and behind a point of interest in a scan direction,

wherein the filter permits filter pass of the point of interest when (a) a brightness difference between the value of the point of lowest brightness within the limits of the object range and the value of the point of interest is not lower than a first threshold value, (b) said brightness difference is not greater than a second threshold value, and (c) said value of the point of lowest brightness is not greater than a third threshold value.

2. The face-image processing apparatus according to claim 1, wherein

said multivalue-image characteristic extracting means extracts a pixel of interest in accordance with distribution of relative brightness of the brightness of the pixel of interest contained in the multivalue face image and the brightness of pixels adjacent to the pixel of interest so as to extract an eye region by using the extracted pixel of interest.

3. The face-image processing apparatus according to claim 2, further comprising:

extracted-image storing means for scoring the extracted pixel of interest, wherein

said multivalue-image characteristic extracting means performs the extraction of the eye region by using the pixel of interest stored in said extracted-image storing means.

4. The face-image processing apparatus according to claim 2, wherein

said multivalue-image characteristic extracting means performs the extraction of the eye region in accordance with distribution of relative brightness in one direction.

5. The face-image processing apparatus according to claim 4, wherein

the distribution of the relative brightness in one direction is the horizontal direction of the face.

6. The face-image processing apparatus according to claim 4, further comprising:

dedicated hardware which performs the extraction of the pixel of interest in accordance with the distribution of the relative brightness.

7. The face-image processing apparatus according to claim 1, wherein

the eye region includes an image reflected by the retina.