Position only fit, POF, algorithm for blur spot target tracking and discrimination

• US 8,655,614 B2
• Filed: 11/30/2007
• Issued: 02/18/2014
• Est. Priority Date: 11/30/2007
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Murata, Ronald N.
• Primary Examiner(s): Kundu, Sujoy
• Assistant Examiner(s): Ngon, Ricky
• Application Number:
  US11/948,132
• Publication Number:
  US 20090144003A1
• Time in Patent Office: 2,272 Days
• Field of Search: 702/66, 702/40, 702/69, 702/86, 702/130, 702134-136, 702 94- 95, 702150-153, 702/179, 382/181, 382/190, 382/206, 382/207, 382/286, 382/291, 382/103, 382/106, 382/109, 382/276, 382/108, 250/341.8, 250/370.1, 250/559.29, 250/559.35, 2502061-2062
• US Class Current: 702/66
• CPC Class Codes: G01J 5/0022 for sensing the radiation of moving bodies
• CPC Class Codes: G06T 7/00 Image analysis

Abstract

A method for determining the amplitude of an infrared object may include receiving an infrared image of the object from a sensor, and expressing the objects infrared amplitude as a function of its position coordinates. The sum of the squared residuals of the objects true infrared response and a model of the objects infrared response may be minimized to determine the centroid of the infrared image. The objects infrared amplitude may then determined based on the centroid location.

Claims

1. A system comprising an infrared sensor;

and a processor programmed to process multiple frames of image data captured by the sensor, wherein the processor is programmed to estimate a centroid of a blur spot target in each of the frames; and

separately estimate radiometric amplitude of the blur spot target in each of the frames according to an expression

2. The system of claim 1, wherein the processor is further programmed to iteratively determine the estimates X1 and Y1 minimizing a sum of squares residuals function of the radiometric amplitude A1(X1,Y1,f).

3. The system of claim 2, wherein the sum of squares residual function SOS(X1,Y1,f) is computed as

4. The system of claim 1, wherein a Monte Carlo method is performed as part of the statistical analysis.

5. The system of claim 1, wherein the statistical analysis is used to evaluate sensor noise and line of sight jitter on the estimated amplitude and centroid.

6. The system of claim 1, wherein the processor is further programmed to iteratively update the estimates X1 and Y1 according to a residual between the blur spot target in the frames and a modeled response of a source at a previously estimated centroid and amplitude.

7. A method comprising:

using an infrared sensor to provide a plurality of images containing an object;

using a processor to estimate a centroid of a blur spot target in each of the images; and

using the processor to separately estimate radiometric amplitude of the blur spot target in each of the images as a function of the estimated centroid and a statistical analysis of the images;

wherein the amplitude is estimated according to an expression

8. The method of claim 7, wherein the processor is further programmed to iteratively determine the estimates X1 and Y1 by minimizing a sum of squares residuals function of the radiometric amplitude A1(X1,Y1,f).

9. The method of claim 8, wherein the sum of squares residual function SOS(X1,Y1,f) is computed as

10. The method of claim 7, wherein a Monte Carlo method is performed as part of the statistical analysis.

11. The method of claim 7, wherein the statistical analysis is used to evaluate sensor noise and line of sight jitter on the estimated amplitude and centroid.

12. The method of claim 7, wherein the processor is further used to iteratively update the estimates X1 and Y1 according to a residual between the blur spot target in the images and a modeled response of a source at a previously estimated centroid and amplitude.

13. An article comprising non-transitory computer readable memory encoded with code that, when executed, causes a computer to:

estimate a centroid of a blur spot target in each of a plurality of images;

separately estimate radiometric amplitude of the blur spot target in each of the images as a function of the estimated centroid and a statistical analysis of the images according to an expression

14. The article of claim 13, wherein a Monte Carlo method is performed as part of the statistical analysis.

15. The article of claim 13, wherein the statistical analysis is used to evaluate sensor noise and line of sight jitter on the estimated amplitude and centroid.

16. The article of claim 13, wherein the estimates X1 and Y1 are iteratively updated according to a residual between the blur spot target in the images and a modeled response of a source at a previously estimated centroid and amplitude.

17. The article of claim 13, wherein the code, when executed, causes the computer to iteratively determine the estimates X1 and Y1 by minimizing a sum of squares residual function of the radiometric amplitude A1(X1,Y1,f).

18. The article of claim 17, wherein the sum of squares residual function SOS(X1,Y1,f) is computed as