Automatic anti-glare exposures for imaging devices

• US 9,503,654 B2
• Filed: 05/30/2014
• Issued: 11/22/2016
• Est. Priority Date: 05/30/2014
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Kaikumaa, Timo
• Primary Examiner(s): Velez, Roberto
• Assistant Examiner(s): COLEMAN, STEPHEN P
• Application Number:
  US14/291,338
• Publication Number:
  US 20150350511A1
• Time in Patent Office: 907 Days
• Field of Search: 348/187
• US Class Current: 1/1
• CPC Class Codes: G03B 13/36 Autofocus systems
• CPC Class Codes: G03B 15/05 Combinations of cameras with electronic flash apparatus; Electronic flash units
• CPC Class Codes: G03B 2206/00 Systems for exchange of information between different pieces of apparatus, e.g. for exchanging trimming information, for photo finishing
• CPC Class Codes: G03B 2215/05 Combinations of cameras with electronic flash units
• CPC Class Codes: G03B 2215/0503 Built-in units
• CPC Class Codes: G03B 7/00 Control of exposure by setting shutters, diaphragms or filters, separately or conjointly control of exposure in television cameras by means of circuitry influencing the optical part of the camera H04N23/75
• CPC Class Codes: H04N 23/56 provided with illuminating means
• CPC Class Codes: H04N 23/64 Computer-aided capture of images, e.g. transfer from script file into camera, check of taken image quality, advice or proposal for image composition or decision on when to take image
• CPC Class Codes: H04N 23/671 in combination with active ranging signals, e.g. using light or sound signals emitted toward objects
• CPC Class Codes: H04N 23/74 by influencing the scene brightness using illuminating means

Abstract

Techniques related to anti-glare exposures for imaging devices and, in particular, for exposures that disable a flash when a flash reflecting surface is detected between the imaging device and an object of interest of the exposure are discussed. Such techniques may include determining a flash reflecting surface is between the imaging device and the object of interest based on a comparison of an autofocus distance to the object of interest and an estimated distance to the flash reflecting surface and disabling the flash based on the determination.

Claims

1. A method for providing anti-glare exposures for an imaging device comprising:

determining an autofocus distance to an object of interest;

estimating a distance to a flash reflecting surface;

determining the flash reflecting surface is between the imaging device and the object of interest based on a comparison of the autofocus distance and the distance to the flash reflecting surface; and

disabling a flash of the imaging device during an exposure of the object of interest based on the determination the flash reflecting surface is between the imaging device and the object of interest.

2. The method of claim 1, wherein the flash reflecting surface is determined to be between the object of interest and the imaging device when a difference between the autofocus distance and the distance to the reflecting surface is greater than a threshold.

3. The method of claim 1, wherein the autofocus distance is based on a determined autofocus distance range, and wherein the autofocus distance comprises at least one of the longest distance in the autofocus distance range, a predetermined value associated with the longest distance in the autofocus distance range, or a logical value associated with the longest distance in the autofocus distance range.

4. The method of claim 1, further comprising:

updating exposure settings for the exposure based on the flash being disabled.

5. The method of claim 1, wherein the imaging device comprises at least one of a camera, a smartphone, an ultrabook, a laptop, or a tablet, and wherein the imaging device is in an auto-exposure mode.

6. The method of claim 1, further comprising:

detecting the flash reflecting surface.

7. The method of claim 6, wherein detecting the flash reflecting surface comprises:

providing a pre-exposure flash; and

comparing a first image frame from before the pre-exposure flash to a second image frame during the pre-exposure flash to determine a reflection of the pre-exposure flash in the second image.

8. The method of claim 7, wherein estimating the distance to the flash reflecting surface comprises estimating the distance to the reflecting surface based on at least one of a size of the reflection or an intensity of the reflection.

9. The method of claim 6, wherein detecting the flash reflecting surface comprises determining an environmental indicator associated with the imaging device, wherein the environmental indicator provides an indication of the environment in which the imaging device is currently located, and wherein estimating the distance to the flash reflecting surface is based on the environmental indicator.

10. The method of claim 9, wherein the environmental indicator is determined based on an aural evaluation of an environment around the imaging device.

11. The method of claim 9, wherein the environmental indicator is determined based on an augmented reality evaluation of an environment around the imaging device.

12. The method of claim 9, wherein the environmental indicator is determined based on a map based evaluation of the imaging device.

13. The method of claim 9, wherein the environmental indicator is determined based on a communications link to a second device.

14. The method of claim 13, wherein the communications link comprises a Bluetooth link and the second device comprises an automobile.

15. A system for providing anti-glare exposures for an imaging device, comprising:

a memory configured to store image data; and

a central processing unit coupled to the memory, wherein the central processing unit comprises;

autofocus circuitry configured to determine an autofocus distance to an object of interest;

flash reflecting surface evaluation circuitry configured to estimate a distance to a flash reflecting surface and to determine the flash reflecting surface is between the imaging device and the object of interest based on a comparison of the autofocus distance and the distance to the flash reflecting surface; and

flash control circuitry configured to disable a flash of the imaging device during an exposure of the object of interest based on the determination the flash reflecting surface is between the imaging device and the object of interest.

16. The system of claim 15, wherein the flash reflecting surface is determined to be between the object of interest and the imaging device when a difference between the autofocus distance and the distance to the reflecting surface is greater than a threshold.

17. The system of claim 15, wherein the flash reflecting surface evaluation circuitry is further configured to detect the flash reflecting surface based on the flash control circuitry being configured to provide a pre-exposure flash and the flash reflecting surface evaluation circuitry being configured to compare a first image frame from before the pre-exposure flash to a second image frame during the pre-exposure flash to determine a reflection of the pre-exposure flash in the second image detect the flash reflecting surface.

18. The system of claim 17, wherein the flash reflecting surface evaluation circuitry is configured to estimate the distance to the flash reflecting surface based on at least one of a size of the reflection or an intensity of the reflection.

19. The system of claim 15, wherein the flash reflecting surface evaluation circuitry is further configured to detect the flash reflecting surface and to estimate the distance to the flash reflecting surface based on an environmental indicator associated with the imaging device, wherein the environmental indicator provides an indication of the environment in which the imaging device is currently located.

20. The system of claim 19, wherein the environmental indicator is based on at least one of an aural evaluation of an environment around the imaging device, an augmented reality evaluation of the environment around the imaging device, a communications link to a second device, or a map based evaluation of the imaging device.

21. At least one non-transitory machine readable medium comprising a plurality of instructions that in response to being executed on an imaging device, cause the imaging device to provide anti-glare exposures by:

determining an autofocus distance to an object of interest;

estimating a distance to a flash reflecting surface;

determining the flash reflecting surface is between the imaging device and the object of interest based on a comparison of the autofocus distance and the distance to the flash reflecting surface; and

disabling a flash of the imaging device during an exposure of the object of interest based on the determination the flash reflecting surface is between the imaging device and the object of interest.

22. The machine readable medium of claim 21 further comprising instructions that cause the computing device to provide anti-glare exposures by detecting the flash reflecting surface, wherein detecting the flash reflecting surface comprises:

providing a pre-exposure flash; and

comparing a first image frame from before the pre-exposure flash to a second image frame during the pre-exposure flash to determine a reflection of the pre-exposure flash in the second image.

23. The machine readable medium of claim 22, wherein estimating the distance to the flash reflecting surface comprises estimating the distance to the reflecting surface based on at least one of a size of the reflection or an intensity of the reflection.

24. The machine readable medium of claim 21 further comprising instructions that cause the computing device to provide anti-glare exposures by detecting the flash reflecting surface, wherein detecting the flash reflecting surface comprises:

determining an environmental indicator associated with the imaging device, wherein the environmental indicator provides an indication of the environment in which the imaging device is currently located, and wherein estimating the distance to the flash reflecting surface is based on the environmental indicator.

25. The machine readable medium of claim 24, wherein the environmental indicator is based on at least one of an aural evaluation of an environment around the imaging device, an augmented reality evaluation of the environment around the imaging device, a communications link to a second device, or a map based evaluation of the imaging device.