Image pickup device, automatic focusing method, automatic exposure method, electronic flash control method and computer program

• US 20030071908A1
• Filed: 09/17/2002
• Published: 04/17/2003
• Est. Priority Date: 09/18/2001
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Shiraishi, Kenji, Sannoh, Masato
• Granted Patent: US 7,298,412 B2
• Time in Patent Office: Days
• US Class Current: 348/345
• CPC Class Codes: H04N 2101/00 Still video cameras
• CPC Class Codes: H04N 23/61 based on recognised objects
• CPC Class Codes: H04N 23/611 where the recognised objects include parts of the human body
• CPC Class Codes: H04N 23/632 for displaying or modifying preview images prior to image capturing, e.g. variety of image resolutions or capturing parameters
• CPC Class Codes: H04N 23/635 Region indicators; Field of view indicators
• CPC Class Codes: H04N 23/675 comprising setting of focusing regions
• CPC Class Codes: H04N 23/70 Circuitry for compensating brightness variation in the scene
• CPC Class Codes: H04N 23/71 Circuitry for evaluating the brightness variation
• CPC Class Codes: H04N 23/74 by influencing the scene brightness using illuminating means

Abstract

There are provided an image memory which stores one image of a subject, an image fetch section which takes in an image from the image memory to another memory or register in a predetermined unit, a control section which takes charge of the overall control, a face characteristic storage section which stores a plurality of characteristics of a face, a recognition and judgment section which recognizes a face from the data from the image fetch section and the data from the face characteristic storage section and judges each portion, an edge detector which detects an edge detection value from the result data thereof, and an output section which outputs the final judgment result to the outside.

Claims

1. An image pickup device provided with an automatic focusing function, comprising:

an image pickup unit which inputs image data corresponding to a subject;

a face detection unit which detects a human face from the image data input from the image pickup unit; and

an automatic focusing control unit which performs automatic focusing control, designating at least a part of the human face detected by the face detection unit as arranging area.

2. The image pickup device according to claim 1, further comprising a notification unit for notifying a user that a human face has been detected by the face detection unit.

3. The image pickup device according to claim 1, wherein when a plurality of faces are detected by the face detection unit, the automatic focusing control unit carries out the automatic focusing control, designating at least a part of the face closest to the central portion as the ranging area.

4. The image pickup device according to claim 1, comprising a ranging area selection unit by which, when a plurality of faces are detected by the face detection unit, a user selects the ranging area from the faces, wherein

the automatic focusing control unit carries out the automatic focusing control, based on the ranging area selected by the ranging area selection unit.

5. The image pickup device according to claim 1, comprising a face detection operation setup unit, by which a user sets permission/inhibition of the face detection operation of the face detection unit, wherein

when permission of the face detection operation of the face detection unit is set by the face detection operation setup unit, the automatic focusing control unit allows the face detection unit to execute the face detection operation, to thereby perform the automatic focusing control by designating at least a part of the detected human face as the ranging area, and when inhibition of the face detection operation of the face detection unit is set by the face detection operation setup unit, the automatic focusing control unit carries out the automatic focusing control, without allowing the face detection unit to execute the face detection operation.

6. The image pickup device according to claim 1, further comprising a mode setup unit which sets a first photographing mode for performing automatic focusing by executing the face detection operation of the face detection unit, or a second photographing mode for performing automatic focusing without executing the face detection operation of the face detection unit, wherein

when the first photographing mode is set by the mode setup unit, the automatic focusing control unit allows the face detection unit to execute the face detection operation, to thereby perform automatic focusing control by designating at least a part of the detected human face as the ranging area, and when the second photographing mode is set by the mode setup unit, the automatic focusing control unit carries out the automatic focusing control, without allowing the face detection unit to execute the face detection operation.

7. The image pickup device according to claim 1, wherein when a human face is detected, the face detection unit further detects eyes, and

when the eyes are detected by the face detection unit, the automatic focusing control unit carries out the automatic focusing control, designating at least a part of the eyes as the ranging area.

8. The image pickup device according to claim 1, wherein when a human face is detected, the face detection unit further detects the eyes, a nose and a mouth, and

the image pickup device further comprises a second ranging area selection unit, by which when the eyes, the nose and the mouth are detected by the face detection unit, a user selects the ranging area from the eyes, the nose and the mouth, and

the automatic focusing control unit carries out the automatic focusing control, based on the ranging area selected by the second ranging area selection unit.

9. The image pickup device according to claim 1, wherein the automatic focusing control unit performs automatic focusing control by setting the size of the ranging area, based on the size of the human face detected by the face detection unit.

10. The image pickup device according to claim 1, further comprising a ranging area size selection unit for a user to select the size of the ranging area, wherein

the automatic focusing control unit performs the automatic focusing control by setting the ranging area of a size selected by the ranging area size selection unit.

11. The image pickup device according to claim 1, wherein every time the automatic focusing control unit performs the automatic focusing control, designating at least a part of the human face detected by the face detection unit as the ranging area, the automatic focusing control unit stores the ranging result in a memory, and predicts the next focusing position from the past ranging results stored in the memory.

12. An automatic focusing method comprising:

an image input step of inputting image data corresponding to a subject;

a face detection step of detecting a human face from the image data input at the image input step; and

an automatic focusing control step of performing automatic focusing control, designating at least a part of the human face detected at the face detection step as a ranging area.

13. A program for a computer to execute:

an image input step of inputting image data corresponding to a subject;

a face detection step of detecting a human face from the image data input at the image input step; and

an automatic focusing control step of performing automatic focusing control, designating at least a part of the human face detected at the face detection step as a ranging area.

14. An image pickup device provided with an automatic exposure function, comprising:

an image pickup unit which inputs image data corresponding to a subject;

a face detection unit which detects a human face from the image data input from the image pickup unit;

a photometric unit which measures optical intensity, designating the human face detected by the face detection unit as a photometric area; and

an exposure control unit which calculates the exposure based on the photometric result of the human face by the photometric unit, and performs exposure control based on the calculated exposure.

15. The image pickup device according to claim 14, wherein the photometric unit measures the optical intensity by designating the whole screen as the photometric area, and

the exposure control unit calculates the exposure by giving more weight to the photometric result of the human face compared with the photometric result of the whole screen, based on the photometric result of the human face and the photometric result of the whole screen by the photometric unit.

16. The image pickup device according to claim 15, wherein the exposure control unit selects either of a first photometric method in which the exposure is calculated based on the photometric result of the human face, and a second photometric method in which the exposure is calculated by giving more weight to the photometric result of the human face compared with the photometric result of the whole screen, based on the photometric result of the human face and the photometric result of the whole screen, corresponding to the ratio of the face occupying in the screen or the position of the face or both.

17. The image pickup device according to claim 15, further comprising a photometric method selection unit, by which a user can select either of a first photometric method in which the exposure is calculated based on the photometric result of the human face, and a second photometric method in which the exposure is calculated by giving more weight to the photometric result of the human face compared with the photometric result of the whole screen, based on the photometric result of the human face and the photometric result of the whole screen.

18. The image pickup device according to claim 15, further comprising a weighting setup unit, by which a user sets weighting to the photometric result of the human face with respect to the photometric result of the whole screen.

19. The image pickup device according to claim 15, wherein the exposure control unit sets weighting to the photometric result of the human face with respect to the photometric result of the whole screen, based on the ratio of the face occupying in the screen or the position of the face or both.

20. The image pickup device according to claim 14, comprising a face detection operation setup unit, by which a user sets permission/inhibition of the face detection operation of the face detection unit, wherein

when permission of the face detection operation of the face detection unit is set, the exposure control unit allows the face detection unit to execute the face detection operation, to thereby perform the exposure control based on the photometric result of the detected human face, and when inhibition of the face detection operation of the face detection unit is set, the exposure control unit performs the exposure control, without allowing the face detection unit to execute the face detection operation.

21. The image pickup device according to claim 14, comprising a mode setup unit for setting a first photographing mode in which exposure control is performed by executing the face detection operation of the face detection unit, or a second photographing mode in which exposure control is performed without executing the face detection operation of the face detection unit, wherein

when the first photographing mode is set, the exposure control unit allows the face detection unit to execute the face detection operation, to thereby perform exposure control based on the photometric result of the detected human face, and when the second photographing mode is set, the exposure control unit performs exposure control without allowing the face detection unit to execute the face detection operation.

22. The image pickup device according to claim 14, comprising a notification unit for notifying a user of the detection result of the human face by the face detection unit.

23. The image pickup device according to claim 22, wherein the notification unit is a monitor screen for displaying the image data.

24. The image pickup device according to claim 22, wherein the notification unit is a sub-LCD for displaying the operation condition or the like of the image pickup device.

25. The image pickup device according to claim 14, wherein the notification unit is an LED.

26. The image pickup device according to claim 14, wherein when a human face cannot be detected by the face detection unit, the exposure control unit performs exposure control based on the photometric result of another photometric method.

27. An automatic exposure method comprising:

an image input step of inputting image data corresponding to a subject;

a face detection step of detecting a human face from the image data input at the image input step;

a photometric step of measuring optical intensity, designating the human face detected at the face detection step as a photometric area; and

an exposure control step of calculating the exposure based on the photometric result of the human face at the photometric step, and performs exposure control based on the calculated exposure.

28. A program for a computer to execute:

an image input step of inputting image data corresponding to a subject;

a face detection step of detecting a human face from the image data input at the image input step;

a photometric step of measuring optical intensity, designating the human face detected at the face detection step as a photometric area; and

an exposure control step of calculating the exposure based on the photometric result of the human face at the photometric step, and performing exposure control based on the calculated exposure.

29. An image pickup device provided with an electronic flash function, comprising:

an image pickup unit which inputs image data corresponding to a subject;

a face detection unit which detects a human face from the image data input from the image pickup unit;

an electronic flashing unit for emitting electronic flash light; and

an electronic flash control unit which controls the electronic flashing unit based on the detection result of the human face by the face detection unit.

30. The image pickup device according to claim 29, wherein when a human face is detected by the face detection unit, the electronic flash control unit allows the electronic flashing unit to perform red-eye preventing emission, and then to perform the main emission.

31. The image pickup device according to claim 29, comprising a red-eye preventing emission mode setup unit, by which a user sets a red-eye preventing emission mode in which red-eye preventing emission is carried out, wherein

when the red-eye preventing emission mode is set by the red-eye preventing emission mode setup unit, and when a human face is detected by the face detection unit, the electronic flash control unit allows the electronic flashing unit to perform red-eye preventing emission, and then to perform the main emission, and when the red-eye preventing emission mode is not set by the red-eye preventing emission mode setup unit, and when a human face is detected by the face detection unit, the electronic flash control unit allows the electronic flashing unit to perform only the main emission, without allowing the electronic flashing to perform the red-eye preventing emission.

32. The image pickup device according to claim 29, wherein when a human face is detected by the face detection unit, and when a ratio of the face occupying in the screen is not smaller than a predetermined value, the electronic flash control unit sets the electronic flash light quantity of the electronic flashing unit to a weak level.

33. The image pickup device according to claim 32, comprising a weak emission quantity setup unit, by which a user sets a quantity to weaken the electronic flash light quantity.

34. The image pickup device according to claim 29, comprising a backlight judgment unit which compares the brightness of the face portion detected by the face detection unit with the ambient brightness, and judges to be backlight when the brightness of the face portion is darker than the ambient brightness by at least a predetermined value, wherein

when it is judged to be backlight by the backlight judgment unit, the electronic flash control unit allows the electronic flashing unit to emit electronic flash light.

35. The image pickup device according to claim 34, comprising a backlight electronic flash setup unit, by which a user sets whether the electronic flashing unit is allowed to emit electronic flash light, when it is judged to be backlight by the backlight judgment unit.

36. The image pickup device according to claim 29, comprising a face detection operation setup unit, by which a user sets whether the electronic flashing unit is to be controlled, based on the detection result of the human face by the face detection unit.

37. The image pickup device according to claim 29, comprising a notification unit for notifying a user of the detection result of a human face by the face detection unit.

38. An electronic flash control method comprising:

an image input step of inputting image data corresponding to a subject;

a face detection step of detecting a human face from the image data input by the image pickup unit; and

an electronic flash control step of controlling the electronic flashing unit for emitting the electronic flash light, based on the detection result of a human face at the face detection step.

39. A program for a computer to execute:

an image input step of inputting image data corresponding to a subject;

a face detection step of detecting a human face from the image data input by the image pickup unit; and

an electronic flash control step of controlling the electronic flashing unit for emitting the electronic flash light, based on the detection result of a human face at the face detection step.

40. An image pickup device comprising:

an image pickup unit which converts an optical image of a subject to image data and outputs this image data;

a face image recognition unit which recognizes face image from the image data; and

a face portion judgment unit which judges each portion in the face image recognized by the face image recognition unit,

wherein when each portion in the face image can all be judged by the face portion judgment unit, a release button for executing photographing of the subject is automatically pressed, or the photographing operation is executed.

41. The image pickup device according to claim 40, wherein when all of the respective portions in the face image cannot be judged by the face portion judgment unit, the operation of the face portion judgment unit is continued until all of the respective portions in the face image can be judged.

42. The image pickup device according to claim 40, wherein the image data is continuously taken in, and only when all of the respective portions in the face image can be judged by the face portion judgement unit, the image data is stored.

43. The image pickup device according to claim 40, wherein the face portion judgment unit has an edge detection unit which detects a characteristic point of the edge for each portion in the face image, and when the edge detection value of the edge detection unit is smaller than a predetermined threshold, control waits until the edge detection value exceeds the threshold, or the operation of the edge detection unit is continued, until the edge detection value exceeds the threshold.

44. The image pickup device according to claim 40, wherein the edge detection unit is repetitively operated, while continuously taking in the image data, and when the edge detection value of the edge detection unit exceeds a predetermined threshold for a predetermined period of time, the image data is taken in, or the release button is pressed.

45. The image pickup device according to claim 40, further comprising a display unit which displays data contents, wherein when photographing conditions are satisfied, this matter is displayed on the display unit.

46. The image pickup device according to claim 45, wherein when the photographing conditions are not satisfied, after a predetermined period of time has passed, this matter is displayed on the display unit.

47. The image pickup device according to claim 40, further comprising a warning unit which generates sound, wherein when the photographing conditions are satisfied, sound is generated by the warning unit.

48. The image pickup device according to claim 47, wherein the warning unit generates sound, when the photographing conditions are not satisfied after a predetermined period of time has passed.

49. The image pickup device according to claim 47, wherein frequency or melody of the sound is changed, between when the photographing conditions are satisfied and when they are not satisfied.

50. The image pickup device according to claim 40, further comprising a selection unit for selecting whether the release button is to be pressed, when the face portion judgment unit detects a face image, and when it is selected not to press the release button by the selection unit, the release button is to be pressed manually.

51. An image pickup device comprising:

an image pickup unit which converts a subject image to image data and outputs this image data; and

a face image recognition unit which recognizes face image from the image data, wherein

when the face image is recognized by the face image recognition unit, the face image portion is cut out and stored as a separate image file.

52. The image pickup device according to claim 51, further comprising a face portion judgment unit which judges each portion in the face image from the data of the face image recognition unit, wherein

when the face image portion is cut out, each portion in the face image is judged by the face portion judgment unit, and the face image portion is cut out so that a straight line substantially connecting the central points of each portion becomes parallel with the vertical direction of an image frame to be cut out.

53. The image pickup device according to claim 51, wherein the blank spaces right and left and top and bottom in the face image face to be cut out from the face image face recognized by the face image recognition unit, are at a certain ratio with respect to the size of the face photographed on the face image face to be cut out.

54. The image pickup device according to claim 51, wherein the data of the face image face recognized by the face image recognition unit and the data of the face image data cut out from the face image face are stored as a file, based on a predetermined relation.

55. The image pickup device according to claim 51, wherein when the face image face is to be cut out, portions other than the cut out face image are painted over by a predetermined color.

56. The image pickup device according to claim 51, further comprising a display unit which displays an image corresponding to the image data photographed by the image photographing unit, wherein

when the face image face is to be cut out, the face image face area to be cut out is displayed by a frame on the display unit.

57. The image pickup device according to claim 51, further comprising:

a display unit which displays an image corresponding to the image data photographed by the image pickup unit; and

a selection unit for selecting recording or deletion of the picked-up image, wherein

recording or deletion of the image can be selected by the selection unit.

58. The image pickup device according to claim 51, wherein when the area of the face occupying in the picked-up image is smaller than a predetermined area, the image is not recorded.

59. The image pickup device according to claim 58, wherein the area of the face is determined by a sum total of the number of pixels occupied by the area.