Target-image position detecting apparatus, method and program for controlling said apparatus

• US 20070065134A1
• Filed: 09/14/2006
• Published: 03/22/2007
• Est. Priority Date: 09/16/2005
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Sugimoto, Masahiko
• Granted Patent: US 7,747,157 B2
• Time in Patent Office: Days
• US Class Current: 396/165
• CPC Class Codes: G01S 3/7864 T.V. type tracking systems
• CPC Class Codes: G06V 40/167 using comparisons between temporally consecutive images
• 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 23/635 Region indicators; Field of view indicators
• CPC Class Codes: H04N 23/67 Focus control based on electronic image sensor signals
• CPC Class Codes: H04N 23/71 Circuitry for evaluating the brightness variation
• CPC Class Codes: H04N 25/134 based on three different wavelength filter elements

Abstract

A face-image area is decided with comparatively good accuracy. An (N−1)th frame of a subject image α1 and an Nth frame of a subject image α2 are obtained by sensing the image of a subject successively. Face-image detection processing is applied to the frames of the subject images α1 and α2 to detect face-image areas C1, C2 and C3. The face-image area C2 is construed to be linked to the face-image area C1, which is the corresponding face-image area. Since a face-image area that corresponds to the face-image area C3 does not exist, the face-image area C3 is construed as not being linked. The linked face-image area C2 in the Nth frame of the subject image α2 is decided upon as a face-image area. Thus, face areas can be decided with comparatively good accuracy.

Claims

1. An apparatus for detecting the position of a target image, comprising:

a first detecting device for detecting a first position at which a target image is present from a first subject image among a plurality of frames of subject images obtained by sensing, simultaneously or successively, the images of subjects regarded as being substantially identical;

a second detecting device for detecting a second position at which the target image is present from a second subject image among the plurality of frames of subject images; and

a deciding device for deciding a position at which the target image is present in at least one of the first and second subject images based upon the first position detected by said first position detecting device and the second position detected by said second position detecting device.

2. The apparatus according to claim 1, further comprising an image sensing device for sensing, simultaneously or successively, the images of subjects regarded as being substantially identical and outputting image data representing a plurality of frames of subject images;

wherein said first detecting device detects the position at which the target image is present from the first subject image among the plurality of subject images represented by the image data that has been output from said image sensing device; and

said second detecting device detects the position at which the target image is present from the second subject image among the plurality of subject images represented by the image data that has been output from said image sensing device.

3. The apparatus according to claim 1, wherein said first detecting device and said second detecting device are a common detecting device.

4. The apparatus according to claim 1, further comprising a position converting device;

wherein if sizes of the first and second subject images are different, said position converting device converts at lease one position of the first position that has been detected by said first detecting device and the second position that has been detected by said second detecting device in such a manner that the at least one position becomes a position that prevails in a case where the size of the first subject image and the size of the second subject image are identical;

said deciding device decides the position at which the target image is present based upon the first and second positions obtained by the conversion performed .by said position converting device.

5. The apparatus according to claim 1, further comprising:

an image sensing device for sensing the image of a subject and outputting image data representing the image of the subject;

a first image-sensing control device for controlling said image sensing device in accordance with a preliminary image-sensing command so as to sense the image of the subject and output first image data representing the first subject image; and

a second image-sensing control device for controlling said image sensing device in accordance with a regular image-sensing command so as to sense the image of the subject and output second image data representing the second subject image;

wherein said first detecting device detects the position at which the target image is present from within the first subject image represented by the first image data that has been output from said image sensing device under the control of said first image-sensing control device, and said second detecting device detects the position at which the target image is present from within the second subject image represented by the second image data that has been output from said image sensing device under the control of said second image-sensing control device.

6. The apparatus according to claim 5, further comprising:

a determination device for determining whether image sensing conforming to the regular image-sensing command is to be performed in sync with a flash light-emission; and

a decision control device, which is responsive to a determination by said determination device that image sensing is to be performed in sync with a flash light-emission, for controlling said deciding device so as to halt decision processing in said deciding device and decide upon the second position, which has been detected by said second detecting device, as the position at which the target image is present.

7. The apparatus according to claim 5, further comprising:

an exposure adjusting device for adjusting amount of exposure of said image sensing device based upon the first image data that is output from said image sensing device based upon control in said first image-sensing control device;

control in said second image-sensing control device causing said image sensing device to output the second image data in response to the regular image-sensing command based upon the amount of exposure obtained by adjustment performed by said exposure adjusting device;

a determination device for determining whether the amount of exposure in said image sensing device controlled by said first image-sensing control device is less than a threshold value; and

a decision control device, responsive to a determination by said determination device that the amount of exposure is less than a threshold value, for controlling said deciding device so as to halt decision processing in said deciding device and decide upon the second position, which has been detected by said second detecting device, as the position at which the target image is present.

8. The apparatus according to claim 1, wherein if the amount of fluctuation between the first position detected by said first detecting device and the second position detected by said second detecting device is equal to or greater than a prescribed threshold value, then said deciding device decides that the target image is not present in at least one of the first and second subject images.

9. The apparatus according to claim 1, wherein said first detecting device detects the first position at which the target image is present from the first subject image, which has been obtained by a first image sensing operation, from among a plurality of frames of subject images obtained by sensing a plurality of times, successively in terms of time, the images of subjects regarded as being substantially identical;

said second detecting device detects the second position at which the target image is present from the second subject image, which has been obtained by a second image sensing operation, from among the plurality of frames of subject images;

said apparatus further comprising a third detecting device for detecting a third position at which the target image is present from a third subject image, which has been obtained by a third sensing image operation, from among the plurality of frames of subject images;

said deciding device decides that the position at which the target image is present is in at least one subject image among the first, second and third subject images based upon the first position, second position and third position detected by said first, second and third detecting devices, respectively.

10. The apparatus according to claim 9, wherein said deciding device decides that the position at which the target image is present is in the third subject image based upon (a) a third position at which, among third positions detected by said third detecting device, a target image corresponding to the second position detected by said second detecting device is not present, and (b) a first position at which, among first positions detected by said first detecting device, target images corresponding to both the second position detected by said second detecting device and the third position detected by said third detecting device are not present.

11. The apparatus according to claim 1, further comprising:

a first image sensing device for outputting first image data representing the first subject image by sensing the image of a subject; and

a second image sensing device for outputting second image data representing the second subject image by sensing the image of the subject;

wherein said first detecting device detects the position at which the target image is present from the first subject image represented by the first image data that has been output from said first image sensing device; and

said second detecting device detects the position at which the target image is present from the second subject image represented by the second image data that has been output from said second image sensing device.

12. The apparatus according to claim 11, wherein said first and second image sensing devices have image-sensing ranges that are the same or different.

13. The apparatus according to claim 12, wherein said first detecting device detects, from the first subject image, the first position at which the target image is present based upon a value of target-image likeliness;

said second detecting device also detects, from the second subject image, the second position at which the target image is present based upon a value of target-image likeliness; and

said deciding device decides the position at which the target image is present based upon the value of target-image likeliness of the target image detected in said first detecting device and the value of target-image likeliness of the target image detected in said second detecting device.

14. The apparatus according to claim 1, further comprising a single-chip solid-state electronic image sensing device in which color filters of a plurality of colors are provided systematically on a photoreceptor surface, said device sensing the image of a subject to thereby output color image data of a plurality of colors representing a color image of the subject;

wherein the first subject image is represented by color image data of a single color in the color image data of the plurality of colors that has been output from said single-chip solid-state electronic image sensing device, and the second subject image is represented by color image data of a color different from that of the color image data of the single color in the color image data of the plurality of colors.

15. The apparatus according to claim 1, further comprising a solid-state electronic image sensing device that includes a plurality of a plurality of solid-state electronic image sensors in which color filters of different colors are provided on a photoreceptor surface, said device sensing the image of a subject to thereby output color image data of different colors;

wherein the first subject image is represented by color image data of one type in the color image data that has been output from said solid-state electronic image sensing device, and the second subject image is represented by color image data of a type different from that of the color image data of the one type in the color image data.

16. The apparatus according to claim 1, further comprising:

a visible-light sensor for sensing the image of a subject to thereby output visible-light image data that represents the first subject image as a visible-light image; and

an infrared sensor for sensing the image of a subject to thereby output infrared-light image data that represents the second subject image as an infrared image;

wherein said first detecting device detects the position at which the target image is present from the first subject image represented by the visible-light image data that has been output from said visible-light sensor; and

said second detecting device detects the position at which the target image is present from the second subject image among the plurality of frames of subject images represented by the infrared image data that has been output from said infrared sensor.

17. The apparatus according to claim 1, further comprising a visible-light/infrared solid-state electronic image sensing device that includes a visible-light filter and an infrared filter, said device sensing the image of a subject to thereby output visible-light image data that represents the first subject image as a visible-light image and infrared image data that represents the second subject image as an infrared image;

wherein said first detecting device detects the position at which the target image is present from the first subject image represented by the visible-light image data that has been output from said visible-light/infrared solid-state electronic image sensing device; and

said second detecting device detects the position at which the target image is present from the second subject image represented by the infrared image data that has been output from said visible-light/infrared solid-state electronic image sensing device.

18. The apparatus according to claim 1, further comprising an image sensing device for sensing the image of a subject at fixed periods and alternately outputting first image data representing a first field of a subject image and image data representing a second field of the subject image;

wherein said first detecting device detects the position at which the target image is present from the first field of the subject image represented by a first field of image data that has been output from said image sensing device; and

said second detecting device detects the position at which the target image is present from the second field of the subject image represented by a second field of image data that has been output from said image sensing device.

19. The apparatus according to claim 2, wherein said image sensing device senses, simultaneously or successively while changing image-sensing conditions, the images of subjects regarded as being substantially identical and outputs image data representing a plurality of frames of subject images.

20. The apparatus according to claim 19, wherein the change in image-sensing conditions is at least one among a change in amount of exposure, f-stop value, shutter speed, amount of focus, amount of zoom, sensitivity and flash.

21. The apparatus according to claim 1, further comprising a signal processing device for sensing the image of a subject and applying different types of signal processing to image data representing one frame of the subject image;

wherein said first detecting device detects the position at which the target image is present from the first subject image represented by image data that has subjected to one type of signal processing among the types of signal processing executed by said signal processing device; and

said second detecting device detects the position at which the target image is present from the second subject image represented by image data that has been subjected to other signal processing different from the one type of signal processing among the types of signal processing executed by said signal processing device.

22. The apparatus according to claim 1, wherein said deciding device decides that a position in the vicinity of a first position at which, among first positions detected by said first detecting device, a target image corresponding to the second position detected by said second detecting device is present, is a position at which the target image is present in the image of the subject.

23. The apparatus according to claim 1, further comprising a hardware control device for exercising hardware control based upon the position, decided by said deciding device, at which the target image is present.

24. The apparatus according to claim 23, wherein the hardware control is at least one among automatic exposure control, automatic focus control, flash control, power-saving control and zoom control.

25. The apparatus according to claim 1, further comprising a signal processing device for executing signal processing based upon the position, decided by said deciding device, at which the target image is present.

26. The apparatus according to claim 25, wherein said signal processing device executes at least one type of signal processing among gain adjustment, white balance adjustment, color correction, contour emphasis, noise reduction and tone correction.

27. The apparatus according to claim 1, wherein the target image the image of a face or eye.

28. A method of detecting the position of a target image, comprising the steps of:

detecting a first position at which a target image is present from a first subject image among a plurality of frames of subject images obtained by sensing, simultaneously or successively, the images of subjects regarded as being substantially identical;

detecting a second position at which the target image is present from a second subject image among the plurality of frames of subject images; and

deciding a position at which the target image is present in at least one of the first and second subject images based upon the first and second positions detected.

29. A program for controlling an apparatus, which is for detecting the position of a target image, so as to cause the apparatus to:

detect a first position at which a target image is present from a first subject image among a plurality of frames of subject images obtained by sensing, simultaneously or successively, the images of subjects regarded as being substantially identical;

detect a second position at which the target image is present from a second subject image among the plurality of frames of subject images; and

decide a position at which the target image is present in at least one of the first and second subject images based upon the first and second positions detected.

30. A recording medium storing the program set forth in claim 29.