Adaptive Exposure Control

• US 20090040364A1
• Filed: 08/08/2006
• Published: 02/12/2009
• Est. Priority Date: 08/08/2005
• Status: Abandoned Application

• Current Assignee: Mep Imaging Technologies Ltd.
• Original Assignee: Mep Imaging Technologies Ltd.
• Inventors: Rubner, Joseph
• Application Number:
  US11/990,158
• Publication Number:
  US 20090040364A1
• Time in Patent Office: Days
• US Class Current: 348/362
• CPC Class Codes: G06T 3/4053 based on super-resolution, i.e. the output image resolution being higher than the sensor resolution
• CPC Class Codes: H04N 23/70 Circuitry for compensating brightness variation in the scene
• CPC Class Codes: H04N 23/741 by increasing the dynamic range of the image compared to the dynamic range of the electronic image sensors

Abstract

A method for constructing a final image using adaptive exposure control in multiple exposure photography, comprising: (a) capturing an exposure; (b) analyzing the exposure at least to determine deficiencies in the exposure; (c) setting exposure parameters for at least one next exposure adapted to construct the final image with ameliorated deficiencies; (d) capturing the at least one next exposure using the set exposure parameters; and, (e) constructing a final image utilizing portions of at least the two exposures.

Claims

1. A method for constructing a final image using adaptive exposure control in multiple exposure photography, comprising:

(a) capturing an exposure;

(b) analyzing the exposure at least to determine deficiencies in the exposure;

(c) setting exposure parameters for at least one next exposure adapted to construct the final image with ameliorated deficiencies;

(d) capturing the at least one next exposure using the set exposure parameters; and

,

(e) constructing a final image utilizing portions of at least the two exposures.

2. A method according to claim 1, wherein setting is conducted to enable sufficient precision of a registration process between the next exposure and the exposure.

5. A method according to any of claims 1-4, wherein analyzing is conducted to determine at least one deficiency including motion blur, overexposure or underexposure, high dynamic range, low contrast, limited depth of field, limited resolution of at least a portion of an exposure.

6. A method according to claim 5, wherein if the deficiency is motion blur an exposure time of the at least one next exposure is reduced.

7. A method according to claim 6, wherein if the reduced exposure time would result in underexposure, additional exposures are taken.

8. A method according to claim 7, and including combining at least potions that are underexposed of said exposure to produce a properly exposed image.

9. A method according to any of claims 5-8, wherein portions of at least two exposures are combined to produce the final image in which the at least one deficiency is ameliorated.

10. A method according to any of claims 5-9, wherein if the deficiency is overexposure an exposure time of the at least one next exposure is reduced.

11. A method according to any of claims 5-10, and including combining useful portions from one exposure and useful portions from the next exposure to produce the final image having overall proper exposure.

12. A method according to any of claims 1-11, further comprising repeating (b)-(d) until a desired final image can be constructed from said exposures.

13. A method according to any of claims 1-12, further comprising registering at least the portions of at least the two exposures before constructing the final image.

14. A method according to any of claims 1-13, wherein analyzing includes sub-dividing the first exposure into regions, and determining the presence of deficiencies on a region by region basis.

15. A method according to claim 14, wherein analyzing comprises, analyzing each region using a measure reflecting at least one of motion blur, overexposure or underexposure, high dynamic range, low contrast, limited depth of field, limited resolution.

16. A method according to claim 14 or claim 15, further comprising classifying the exposure time of each region as done, valid, short or long.

17. A method according to claim 16, wherein classifying a region as long indicates overexposure.

18. A method according to claim 16 or claim 17, wherein classifying a region as short indicates underexposure.

19. A method according to any of claims 16-18, wherein classifying a region as valid indicates an acceptable exposure time.

20. A method according to any of claims 16-19, wherein classifying a region as done indicates acceptable motion blur and exposure time.

21. A method according to any of claims 1-20, wherein a plurality of integration times are set for at least one exposure.

22. A method according to any of claims 1-21, wherein setting exposure parameters includes setting at least one of focus, exposure time, aperture, zoom, flash or other lighting source and/or vibration.

23. A method according to any of claims 1-19, wherein at least a portion of the analyzing is performed on remote device.

32. A multiple exposure photography device, comprising:

a storage; and

,

a controller, wherein the controller is programmed with software adapted for carrying out a method of any of claims 1-31.

3. A method for acquiring registerable exposures for constructing a final image in multiple exposure photography, comprising:

providing at least one feature to a multiple exposure photography camera; and

,

utilizing an adaptive exposure control method to acquire the exposures, comprising

(a) capturing an exposure;

(b) analyzing the exposure at least to determine deficiencies in the exposure;

(c) modifying the at least one feature for at least one next exposure to create the final image which exhibits ameliorated deficiencies, while allowing registration; and

,

(d) capturing the at least one next exposure using the at least one feature modification.

4. A method according to claim 3, wherein providing at least one feature includes providing at least one of a focus control, an exposure control, an aperture control, a zoom, a flash control or other lighting source usage, and/or a vibration mechanism control to the camera.

24. A method for improving the depth-of-field of a final image in multiple exposure photography, comprising:

determining an aperture setting and exposure time, in order to ameliorate a motion blur, that gives the desired depth of field but does not give an adequate exposure;

capturing a plurality of exposures using the determined aperture setting; and

,

generating a final image from a combination of the captured plurality of exposures.

25. A method for reducing aberrations in a final image of multiple exposure photography, comprising:

capturing a first exposure;

analyzing the first exposure to identify aberrations;

capturing at least one other exposure responsive to said analyzing, wherein the first exposure or one of the at least one other exposures is designated a reference exposure; and

creating a final image without the identified aberrations utilizing at least a portion of the reference exposure and at least one of the other exposures.

26. A method according to claim 25, wherein analyzing includes identifying at least one of eye blink or movement.

27. A method according to claim 26 wherein creating comprises replacing a portion of the first exposure which has the aberration with a portion of the at least one other exposure which does not have the aberration.

28. A method for analyzing and compensating for imaging artifacts in an adaptive multiple exposure photography camera, comprising:

capturing a series of exposures using the camera;

collecting statistics on the series of exposures;

analyzing the statistics to identify camera based artifacts;

creating camera calibration parameters to compensate for the artifacts based on the analyzing; and

,

utilizing the camera calibration parameters when taking at least one exposure subsequent to the series.

29. A method according to claim 28, wherein analyzing the statistics includes analyzing for at least one of distortion, vignetting, or at least one bad pixel.

30. A method according to claim 29, wherein analyzing for distortion includes determining differences in neighboring local motion vectors over the average of the series of multiple exposures.

31. A method according to claim 29 or claim 30, wherein analyzing the series for at least one of vignetting or at least one bad pixel includes averaging pixel values, after compensating for the exposure parameters.