METHOD AND DEVICE FOR RECOVERING A DIGITAL IMAGE FROM A SEQUENCE OF OBSERVED DIGITAL IMAGES

• US 20130242129A1
• Filed: 09/28/2011
• Published: 09/19/2013
• Est. Priority Date: 09/28/2010
• Status: Active Grant

• Current Assignee: Max-Planck-Gesellschaft Zur Foerderung Der Wissenschaften e.V. (Max-Planck-Gesellschaft zur Frderung der Wissenschaften e)
• Original Assignee: Bernhard Scholkopf
• Inventors: Harmeling, Stefan, Hirsch, Michael, Sra, Suvrit, Schlkopf, Bernhard, Schuler, Christian J.
• Granted Patent: US 10,032,254 B2
• Time in Patent Office: Days
• US Class Current: 348/222.1
• CPC Class Codes: G06T 2207/20201 Motion blur correction
• CPC Class Codes: G06T 5/00 Image enhancement or restoration
• CPC Class Codes: G06T 5/73 Deblurring; Sharpening
• CPC Class Codes: H04N 23/60 Control of cameras or camera modules
• CPC Class Codes: H04N 23/683 performed by a processor, e.g. controlling the readout of an image memory
• CPC Class Codes: H04N 23/80 Camera processing pipelines; Components thereof
• CPC Class Codes: H04N 25/61 the noise originating only from the lens unit, e.g. flare, shading, vignetting or "cos4"

Abstract

A computer-implemented method for recovering a digital image (x) from a sequence of observed digital images (y₁, . . . , y_T), includes: obtaining an observed digital image (y_t); estimating a point spread function (f_t) based on the observed image (y_t); estimating the recovered digital image (x), based on the estimated point spread function (f_t) and the observed image (y_t); and repeating the above steps. In order to correct optical aberrations of a lens, a point spread function of the lens may be used.

Claims

1. Computer-implemented method for reconstructing a true image (x) from an image (y) acquired by an image acquisition device, the image acquisition device having a lens, comprising the steps of

obtaining the acquired image (y) in digital form;

estimating the true image (x), based on the acquired image in digital form and a point spread function (A) of the lens; and

outputting true estimated true image (x).

2. The method according to claim 1, wherein the point spread function (A) of the lens is a space-variant point spread function (A).

3. The method according to claim 2, wherein each color channel of the true image (x) is estimated by a separate space-variant point spread function (FR, FG, FB).

4. The method according to claim 2, wherein estimating the true image (x) also corrects for vignetting.

5. The method according to claim 3, wherein the step of estimating is further based on a model of a color filter array (CFA) of the image acquisition device.

6. The method according to claim 2, wherein the point spread function (A) of the lens is determined by automatically measuring the lens using a point light source.

7. The method according to claim 2, wherein the lens is a compound lens.

8. The method according to claim 1, wherein the image acquisition device is an electron microscope.

9. Device for reconstructing a true image (x) from an image (y) acquired by an image acquisition device, the image acquisition device having a lens, comprising:

means for obtaining the acquired image (y) in digital form;

means for estimating the true image (x), based on the acquired image in digital form and a point spread function (A) of the lens; and

means for outputting true estimated true image (x).

10. Device according to claim 9, wherein the point spread function (A) is a space-variant point spread function.

11. Computer-implemented method for recovering a digital image (x) from a sequence of observed digital images (y₁, . . . , y_T), comprising the steps:

obtaining an observed digital image (y_t);

estimating a point spread function (f_t) based on the observed image (y_t);

estimating the recovered digital image (x), based on the estimated point spread function (f_t) and the observed image (y_t);

repeating the above steps.

12. The method according to claim 11, wherein the recovered digital image (x) has a higher resolution than the observed digital image (y_t).

13. The method according to claim 11, or 12, wherein saturated pixels in the observed digital image are at least partially disregarded.

14. The method according to claim 11, applied to an individual color channel of the sequence of observed digital images (y₁, . . . , y_T).

15. The method according to claim 11, wherein all color channels of the recovered image (x) are estimated simultaneously.

16. The method according to claim 11, wherein

the observed image is divided into patches;

a multitude of point spread functions (f_t) are jointly estimated, one for each patch; and

the recovered digital image (x) is estimated based on the jointly estimated point spread functions (f_t) and the observed image.

17. The method according to claim 16, further comprising the steps of

removing noise by bilateral filtering;

and

emphasizing edges by shock filtering

of the observed digital image (y_t).

18. Method according to claim 11, wherein the method is executed online.

19. Method according to claim 11, wherein the sequence of observed digital images (y₁, . . . , y_T) is a sequence of astronomical images.

20. Method according to claim 11, wherein the sequence of observed digital images (y₁, . . . , y_T), is a sequence of magnetic resonance images (MRI).

21. Device for recovering a digital image (x) from a sequence of observed digital images (y₁, . . . , y_T), comprising

a module for obtaining an observed digital image (y_t);

a module for estimating a point spread function (f_t) based on the observed image (y_t);

a module for estimating the recovered digital image (x), based on the estimated point spread function (f_t) and the observed image (y_t);

wherein

the device is adapted to execute a method according to claim 11.

22. Computer-readable medium, storing digital images recovered a method according to claim 11.