Extended range image processing for electro-optical systems

• US 7,103,235 B2
• Filed: 04/25/2001
• Issued: 09/05/2006
• Est. Priority Date: 04/25/2001
• Status: Expired due to Term

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Alderson, Timothy, Tener, Gene D., Benton, Richard W. Sr.
• Primary Examiner(s): Johns, Andrew W.
• Assistant Examiner(s): Edwards, Patrick L
• Application Number:
  US09/841,079
• Publication Number:
  US 20020159651A1
• Time in Patent Office: 1,959 Days
• Field of Search: 382/254, 382/255, 382/266, 382/269, 382/275, 382298-300, 382/284, 382/294
• US Class Current: 382/294
• CPC Class Codes: G06T 5/20 using local operators
• CPC Class Codes: G06T 5/50 using two or more images, e.g. averaging or subtraction
• CPC Class Codes: H04N 25/63 applied to dark current
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

A method and apparatus for processing imagery using images acquired via any known Electro-Optical (EO) system. In accordance with exemplary embodiments of the present invention, a first frame of data is selected as a template frame (e.g., a given frame). A second frame of data can be captured using the EO system. At least a portion of the second frame can be correlated with the template frame to generate a shift vector. The second frame can then be registered with the template frame by interpolating the second frame using the shift vector and re-sampling at least a portion of the second frame to produce a registered frame. The template frame can also be re-sampled. The registered frame and the re-sampled template frame can then be combined to generate an averaged frame. The averaged frame can be spatially filtered to enhance edges within the averaged frame.

Claims

1. A method for processing imagery using an Electro-Optical (EO) system, comprising the steps of:

selecting a first frame of data as a template frame;

capturing a second frame of data using the EO system;

correlating at least a portion of the second frame with the template frame to generate a shift vector;

registering the second frame with the template frame by interpolating the second frame using the shift vector and re-sampling by spatially oversampling at least a portion of the second frame by a factor greater than one to produce a registered frame;

re-sampling the template frame;

combining the re-sampled template frame and the registered frame to generate an averaged frame; and

selecting the averaged frame as an updated template frame to which a subsequently captured frame of data is registered, wherein the first and second frames are obtained from a stationary infrared imagery.

2. The method of claim 1, wherein the step of registering the second frame uses bilinear interpolation.

3. The method of claim 1, comprising the step of:

adding motion to a line of sight of the EO system using a commanded line of sight pattern or a random pattern to generate multiple frames of data.

4. The method of claim 1, comprising the step of:

spatially filtering the averaged frame to enhance edges within the averaged frame.

5. The method of claim 1, comprising the step of:

utilizing a histogram projection to change a pixel depth of the averaged frame.

6. The method of claim 1, comprising the step of:

re-sampling the averaged frame.

7. The method of claim 6, wherein the step of re-sampling the averaged frame uses bilinear interpolation.

8. The method of claim 1, comprising the steps of:

capturing a first frame of data using the EO system; and

temporally filtering at least the first frame to generate the template frame.

9. The method of claim 8, wherein the step of re-sampling the template frame uses bilinear interpolation.

10. The method of claim 1, comprising successively selecting further frames of data at intervals of a predetermined number of frames to be updated template frames.

11. An Electro-Optical (EO) system for processing imagery, comprising:

a sensor for generating input data; and

a processor module coupled to the sensor, the processor module configured to;

select a first frame of data as a template frame;

capture a second frame of data using the EO system;

correlate at least a portion of the second frame with the template frame to generate a shift vector;

register the second frame with the template frame by interpolating the second frame using the shift vector and re-sampling by spatially oversampling at least a portion of the second frame by a factor greater than one to produce a registered frame;

re-sample the template frame;

combine the re-sampled template frame and the registered frame to generate an averaged frame; and

select the averaged frame as an updated template frame to which a subsequently captured frame of data is registered, wherein the first and second frames are obtained from a stationary infrared imagery.

12. The EO system of claim 11, wherein the processor module, in registering the second frame, is configured to use bilinear interpolation.

13. The EO system of claim 11, wherein the processor module is configured to:

add motion to a line of sight of the EO system using a commanded line of sight pattern or a random pattern to generate multiple frames of data.

14. The EO system of claim 11, wherein the processor module is configured to:

spatially filter the averaged frame to enhance edges within the averaged frame.

15. The EO system of claim 11, wherein the processor module is configured to:

utilize a histogram projection to change a pixel depth of the averaged frame.

16. The EO system of claim 11, wherein the processor module is configured to:

re-sample the averaged frame.

17. The EO system of claim 16, wherein the processor module, in re-sampling the averaged frame, is configured to use bilinear interpolation.

18. The EO system of claim 11, wherein the processor module is configured to:

capture a first frame of data using the EO system; and

temporally filter at least the first frame to generate the template frame.

19. The EO system of claim 18, wherein the processor module, in re-sampling the template frame, is further configured to use bilinear interpolation.

20. The apparatus of claim 11, wherein the processor module is configured to successively select further frames of data at intervals of a predetermined number of frames to be updated template frames.