BLIND RESTORATION OF IMAGES DEGRADED BY ISOTROPIC BLUR

• US 20100080487A1
• Filed: 10/22/2007
• Published: 04/01/2010
• Est. Priority Date: 10/23/2006
• Status: Active Grant

• Current Assignee: Ben Gurion University of The Negev
• Original Assignee: Ben Gurion University of The Negev
• Inventors: Shacham, Omri, Yitzhaky, Yitzhak, Haik, Oren
• Granted Patent: US 8,249,357 B2
• Time in Patent Office: Days
• US Class Current: 382/266
• CPC Class Codes: G06T 5/20 using local operators
• CPC Class Codes: G06T 5/73 Deblurring; Sharpening
• CPC Class Codes: G06T 7/13 Edge detection

Abstract

A system and a method for automatic restoration of isotropic degradations of a digital image, based on receiving a blurred image by an image capture assembly, automatically finding proper step edge, calculating the PSF from the step edge, and restoring the blurred image by means of a processor, and with the option to display the resorted image by means of an output assembly.

Claims

1. A system for automatic restoration of isotropic degradations of a digital image, the system comprising:

(a) an image capture assembly; and

(b) a processor, which is coupled to process automatically said digital image so as to derive a restoration of said digital image.

2. The system for automatic restoration of isotropic degradations of a digital image of claim 1, wherein said processor includes:

(i) a memory, wherein said memory includes software instructions, wherein said software instructions executing a preprogrammed logic algorithm including the stages of;

A. receiving a blurred image;

B. finding automatically a proper step edge;

C. calculating a PSF from the step edge; and

D. restoring said blurred image.

3. The system for automatic restoration of isotropic degradations of a digital image of claim 2, wherein said memory does not store previous knowledge about a point spread function of a disturbance.

4. The system for automatic restoration of isotropic degradations of a digital image of claim 2, wherein said algorithm includes no iterative stage.

5. The system for automatic restoration of isotropic degradations of a digital image of claim 2, wherein said algorithm calculates said PSF from information that can be found in said image.

6. The system for automatic restoration of isotropic degradations of a digital image of claim 2 further comprising:

(c) an output assembly, wherein said output assembly can receive a restored image from said processor.

7. The system for automatic restoration of isotropic degradations of a digital image of claim 2, wherein said image capture assembly is a digitizing equipment.

8. The system for automatic restoration of isotropic degradations of a digital image of claim 2, wherein said image capture assembly is a CCD camera.

9. The system for automatic restoration of isotropic degradations of a digital image of claim 2, wherein said image capture assembly is an infrared camera.

10. The system for automatic restoration of isotropic degradations of a digital image of claim 6, wherein said output assembly is a display screen.

11. A method for automatic restoration of isotropic degradations of a digital image, the method comprising the stages of:

receiving a blurred image;

automatically finding a proper step edge;

calculating a PSF from the step edge; and

restoring said blurred image as a resorted image according to said PSF.

12. The method for automatic restoration of isotropic degradations of a digital image of claim 11 further comprising the stage of:

displaying said restored image.

13. The method for automatic restoration of isotropic degradations of a digital image of claim 11 wherein said stage of automatically finding proper step includes:

finding edges in said blurred image;

erasing edge pixels having more than two neighbors;

recognizing an angle among neighbors of each edge pixel;

finding straight and long edges according to said angles;

finding edge pixels with homogenous areas in both sides of the said edges, and with high contrast; and

selecting the most appropriate edge.

14. The method for automatic restoration of isotropic degradations of a digital image of claim 11 wherein said stage of calculating the PSF from the step edge includes;

selecting a few vectors of the 2-D edge;

constructing ESF; and

using said vectors for calculating a LSF.

15. A method for automatic restoration of isotropic degradations of a digital image, the method comprising:

receiving a blurred image;

finding edges in said blurred image, said edges having a plurality of edge pixels;

erasing edge pixels having more than two neighbors;

recognizing an angle among neighbors of each edge pixel;

finding straight and long edges according to said angles;

finding edge pixels with homogenous areas in both sides of the said edges, and with high contrast;

selecting the most appropriate edge;

selecting a few vectors of 2-D edge;

constructing an ESF;

using said vectors for calculating a LSF;

restoring said blurred image as a resorted image; and

displaying said restored image.