Synthetic panchromatic imagery method and system

• US 7,298,922 B1
• Filed: 07/07/2004
• Issued: 11/20/2007
• Est. Priority Date: 07/07/2004
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Christie, David Nicholas, Lindgren, John Elmer
• Primary Examiner(s): KASSA, YOSEF
• Application Number:
  US10/886,999
• Time in Patent Office: 1,231 Days
• Field of Search: 382/164, 382/167, 382/284, 382/294, 358/1.2, 358/518, 358/520, 342/25.A, 342/409
• US Class Current: 382/294
• CPC Class Codes: G06T 2207/10036 Multispectral image; Hyperspectral image
• CPC Class Codes: G06T 2207/10041 Panchromatic image
• CPC Class Codes: G06T 3/4061 by injecting details from different spectral ranges
• CPC Class Codes: G06T 5/50 using two or more images, e.g. averaging or subtraction
• CPC Class Codes: G06T 7/32 using correlation-based methods

Abstract

Method and system for generating synthetic panchromatic imagery. A method for making a multi-spectral image includes capturing a panchromatic image of an imaging target. Additionally, the method includes capturing at least a first spectral image of the imaging target in a first spectral bandwidth, and capturing at least a second spectral image of the imaging target in a second spectral bandwidth. Also, the method includes determining at least a first spectral weight and a second spectral weight for the first spectral image and the second spectral image respectively. Additionally, the method includes generating a synthetic panchromatic image, determining a registration offset between the synthetic panchromatic image and the captured panchromatic image, warping the first spectral image and the second spectral image, and generating a multi-spectral image.

Claims

1. A method for making a multi-spectral image, the method comprising:

capturing a panchromatic image of an imaging target, the captured panchromatic image being associated with a captured panchromatic resolution;

capturing at least a first spectral image of the imaging target in a first spectral bandwidth, the first spectral image being associated with a first spectral resolution;

capturing at least a second spectral image of the imaging target in a second spectral bandwidth, the second spectral image being associated with a second spectral resolution;

determining at least a first spectral weight and a second spectral weight for the first spectral image and the second spectral image respectively based on at least information associated with the captured panchromatic image, the first spectral image and the second spectral image;

generating a synthetic panchromatic image based on at least information associated with the first spectral image, the second spectral image, the first spectral weight, and the second spectral weight, the synthetic panchromatic image being associated with a synthetic panchromatic resolution;

determining a registration offset between the synthetic panchromatic image and the captured panchromatic image by matching a first pixel on the synthetic panchromatic image and a second pixel on the captured panchromatic image, the first pixel and the second pixel corresponding to a same portion of the imaging target;

warping the first spectral image and the second spectral image based on at least information associated with the registration offset;

generating a multi-spectral image based on at least information associated with the first spectral image, the second spectral image, the first spectral weight, the second spectral weight, the captured panchromatic image, and the registration offset, the generated multi-spectral image being associated with a third resolution.

2. The method of claim 1 wherein the generating a synthetic panchromatic image is free from using information associated with the captured panchromatic image.

3. The method of claim 1 wherein the third resolution is higher than the first spectral resolution and the second spectral resolution.

4. The method of claim 1 wherein the captured panchromatic resolution is higher than the first spectral resolution and the second spectral resolution.

5. The method of claim 4 wherein the captured panchromatic resolution is higher than the synthetic panchromatic resolution.

6. The method of claim 5 wherein the synthetic panchromatic resolution is equal to the first spectral resolution and the second spectral resolution.

7. The method of claim 1 wherein the first spectral weight ranges from 0% to 100%.

8. The method of claim 7 wherein a sum of the first spectral weight and the second spectral weight is smaller than or equal to 100%.

9. The method of claim 8 wherein the determining at least a first spectral weight and a second spectral weight uses at least a linear spectral model.

10. The method of claim 9 wherein the determining at least a first spectral weight and a second spectral weight uses at least intensities of pixels located in a first portion of the captured panchromatic image, a second portion of the first spectral image, and a third portion of the second spectral image.

11. The method of claim 1 wherein the determining a registration offset comprises maximizing a correlation between the synthetic panchromatic image and the captured panchromatic image.

12. The method of claim 11 wherein the determining a registration offset further comprises:

processing at least information associated with the synthetic panchromatic image and the captured panchromatic image;

modifying at least one of the synthetic panchromatic resolution and the captured panchromatic resolution based on at least information associated with the synthetic panchromatic image and the captured panchromatic image;

wherein in response to the modifying at least one of the synthetic panchromatic resolution and the captured panchromatic resolution, the synthetic panchromatic resolution equals the captured panchromatic resolution.

13. The method of claim 12 wherein the maximizing a correlation between the synthetic panchromatic image and the captured panchromatic image comprises:

translating the synthetic panchromatic image and the captured panchromatic image with respect to each other by a first offset value;

determining a first correlation value corresponding to the first offset value;

translating the synthetic panchromatic image and the captured panchromatic image with respect to each other by a second offset value;

determining a second correlation value corresponding to the second offset value;

processing at least information associated with the first correlation value, the first offset value, the second correlation value, and the second offset value;

fitting the correlation as a function of the registration offset based on at least information associated with the first correlation value, the first offset value, the second correlation value, and the second offset value;

determining a maximum correlation and the registration offset corresponding to the maximum correlation.

14. The method of claim 1 wherein the generating a multi-spectral image comprises:

re-sampling at least the first spectral image and the second spectral image based on information associated with the captured panchromatic resolution;

synthesizing the multi-spectral image based on at least information associated with the re-sampled first spectral image, the re-sampled second spectral image, and the captured panchromatic image.

15. A method for making a multi-spectral image, the method comprising:

capturing a panchromatic image of an imaging target, the captured panchromatic image being associated with a captured panchromatic spatial resolution;

capturing at least a first spectral image of the imaging target in a first spectral bandwidth, the first spectral image being associated with a first spectral spatial resolution, the first spectral spatial resolution being lower than the captured panchromatic spatial resolution;

capturing at least a second spectral image of the imaging target in a second spectral bandwidth, the second spectral image being associated with a second spectral spatial resolution, the second spectral spatial resolution being lower than the captured panchromatic spatial resolution;

generating a synthetic panchromatic image based on at least information associated with the first spectral image and the second spectral image, the synthetic panchromatic image being associated with a synthetic panchromatic spatial resolution;

processing at least information associated with the synthetic panchromatic image and the captured panchromatic image;

determining a registration offset between the synthetic panchromatic image and the captured panchromatic image by matching a first pixel on the synthetic panchromatic image and a second pixel on the captured panchromatic image, the first pixel and the second pixel corresponding to a same portion of the imaging target;

warping the first spectral image and the second spectral image based on at least information associated with the registration offset;

generating a multi-spectral image based on at least information associate with the first spectral image, the second spectral image, the first spectral weight, the second spectral weight, the captured panchromatic image, and the registration offset, the multi-spectral image being associated with a third spatial resolution, the third spatial resolution being substantially equal to the captured panchromatic spatial resolution.

16. The method of claim 15 wherein the third spatial resolution is higher than the synthetic panchromatic spatial resolution.

17. The method of claim 15 wherein the multi-spectral image is free from image distortion, smeared color, and saturated color.

18. The method of claim 15 wherein the generating a synthetic panchromatic image is free from using information associated with the captured panchromatic image.

19. The method of claim 15 wherein the first spectral spatial resolution equals the second spectral spatial resolution.

20. The method of claim 19 wherein the synthetic panchromatic spatial resolution equals the first spectral spatial resolution.

21. The method of claim 15 wherein the determining a registration offset comprises maximizing a correlation between the synthetic panchromatic image and the captured panchromatic image.

22. The method of claim 21 wherein the determining a registration offset further comprises:

processing at least information associated with the synthetic panchromatic image and the captured panchromatic image;

modifying at least one of the synthetic panchromatic spatial resolution and the captured panchromatic spatial resolution based on at least information associated with the synthetic panchromatic image and the captured panchromatic image;

wherein in response to the modifying at least one of the synthetic panchromatic spatial resolution and the captured panchromatic spatial resolution, the synthetic panchromatic spatial resolution equals the captured panchromatic spatial resolution.

23. The method of claim 21 wherein the maximizing a correlation between the synthetic panchromatic image and the captured panchromatic image comprises:

translating the synthetic panchromatic image and the captured panchromatic image with respect to each other by a first offset value;

determining a first correlation value corresponding to the first offset value;

translating the synthetic panchromatic image and the captured panchromatic with respect to each other by a second offset value;

determining a second correlation value corresponding to the second offset value;

processing at least information associated with the first correlation value, the first offset value, the second correlation value, and the second offset value;

fitting the correlation as a function of the registration offset based on at least information associated with the first correlation value, the first offset value, the second correlation value, and the second offset value;

determining a maximum correlation and the registration offset corresponding to the maximum correlation.

24. The method of claim 15 wherein the generating a multi-spectral image comprises:

re-sampling the first spectral image and the second spectral image based on at least information associated with the captured panchromatic spatial resolution;

synthesizing the multi-spectral image based on at least information associated with the re-sampled the re-sampled, and the captured panchromatic image.

25. A method for making a color image, the method comprising:

capturing a panchromatic image of an imaging target, the captured panchromatic image being associated with a captured panchromatic resolution;

capturing at least a first spectral image of the imaging target in a first spectral bandwidth, the first spectral image being associated with a first spectral resolution;

capturing at least a second spectral image of the imaging target in a second spectral bandwidth, the second spectral image being associated with a second spectral resolution;

determining at least a first spectral weight and a second spectral weight for the first spectral image and the second spectral image respectively based on at least information associated with the captured panchromatic image, the first spectral image and the second spectral image;

generating a synthetic panchromatic image based on at least information associated with the first spectral image, the second spectral image, the first spectral weight, and the second spectral weight, the synthetic panchromatic image being associated with a synthetic panchromatic resolution;

determining a registration offset between the synthetic panchromatic image and the captured panchromatic image by matching a first pixel on the synthetic panchromatic image and a second pixel on the captured panchromatic image, the first pixel and the second pixel corresponding to a same portion of the imaging target;

warping the first spectral image and the second spectral image based on at least information associated with the registration offset;

generating a color image based on at least information associated with the first spectral image, the second spectral image, the first spectral weight, the second spectral weight, the captured panchromatic image, and the registration offset, the generated multi-spectral image being associated with a third resolution;

wherein the color image is free from image distortion, smeared color, and saturated color.