Imaging data correction system and method

• US 8,928,758 B2
• Filed: 05/06/2013
• Issued: 01/06/2015
• Est. Priority Date: 06/18/2012
• Status: Active Grant

• Current Assignee: Corelis Incorporated (Electronic Warfare Associates Incorporated)
• Original Assignee: Electronic Warfare Associates Incorporated
• Inventors: Guerreri, Carl N., Foster, Lester Anderson III
• Primary Examiner(s): YENKE, BRIAN P
• Application Number:
  US13/887,407
• Publication Number:
  US 20130335580A1
• Time in Patent Office: 610 Days
• Field of Search: 348/180, 348/188
• US Class Current: 348/188
• CPC Class Codes: G06T 2207/10004 Still image; Photographic image
• CPC Class Codes: G06T 2207/10048 Infrared image
• CPC Class Codes: G06T 5/80 Geometric correction
• CPC Class Codes: G06T 7/80 Analysis of captured images to determine intrinsic or extrinsic camera parameters, i.e. camera calibration
• CPC Class Codes: H04N 17/002 for television cameras
• CPC Class Codes: H04N 23/10 for generating image signals from different wavelengths
• CPC Class Codes: H04N 23/88 for colour balance, e.g. white-balance circuits or colour temperature control

Abstract

Methods and systems for use in calibrating imaging data, are provided that include using a calibration array to generate a test pattern. The calibration array can emit a test pattern having geometric, temporal, and electromagnetic characteristics. The collected data can be compared with the geometric, temporal and electromagnetic characteristics to determine an error factor that can then be used in analyzing the collected data.

Claims

1. A method of correcting imaging data received from a sensor for environmental effects, the method comprising:

placing a calibration system a distance from an object that is in a monitored environment from which imaging data is to be collected by a sensor during a data collection time period, in an environment comparable to the monitored environment, the calibration system being configured to emit a test pattern having geometric, temporal, and electromagnetic characteristics, the calibration system having at least one emission point, each emission point including at least one emission source that emits in a region of the electromagnetic spectrum, the calibration system and the object being sufficiently far from the sensor so that imaging data collected by the sensor is distorted by atmospheric variables;

emitting the test pattern having geometric, temporal, and electromagnetic characteristics with the calibration system;

collecting imaging data from the calibration system with a sensor;

comparing the imaging data collected by the sensor from the test pattern to the geometric, temporal, and electromagnetic characteristics of the test pattern to determine distortion caused by the atmospheric variables;

determining an imaging error factor based on differences between the imaging data collected by the sensor from the test pattern and the geometric, temporal, and electromagnetic characteristics of the test pattern; and

correcting the imaging data collected by the sensor from the object during the data collection time period by the error factor to reduce the distortion caused by the atmospheric variables.

2. The method of claim 1, wherein the test pattern is a trans-spectral test pattern and the sensor is a trans-spectral sensor.

3. The method of claim 1, wherein each emission point comprises a plurality of emission sources, and each emission source emit with a different electromagnetic signature.

4. The method of claim 1, wherein the calibration system comprises a calibration array, and each emission point is located at a known location on the calibration array.

5. The method of claim 4, wherein the calibration array comprises a non-emitting surface that is non-reflective.

6. The method of claim 4, wherein the calibration array comprises a panel of known trans-spectral reflectance.

7. The method of claim 1, wherein the calibration system further includes a control unit operatively connected to the at least one emission point, and the method further comprises:

providing test pattern commands from the control unit to the at least one emission point in order to cause the at least one emission point to emit the test pattern, wherein the test pattern commands include the geometric, temporal, and electromagnetic characteristics of the test pattern.

8. The method of claim 7, further comprising:

receiving the test pattern commands from a remote location at a communications receiver of the calibration system; and

providing the test pattern commands from the communications receiver to the control unit.

9. The method of claim 1, further comprising:

collecting test pattern data using test equipment of the calibration system during the emitting, the test pattern data including the state of each emission point of the calibration array; and

transmitting the test pattern data from a transmitter of the calibration system to a remote location.

10. The method of claim 9, further comprising:

comparing the test pattern data to the geometric, temporal, and electromagnetic characteristics of the test pattern to determine a test pattern error factor based on any differences between the test pattern data and the geometric characteristics and electromagnetic characteristics of the test pattern; and

adjusting the imaging error factor based on the test pattern error factor.

11. The method of claim 1, further comprising:

collecting environmental data using an environmental monitor of the calibration system regarding the environment in which the calibration system is placed; and

communicating the environmental data from a transmitter of the calibration system to a remote location.

12. The method of claim 1, further comprising:

receiving global positioning signals at a GPS receiver of the calibration system; and

transmitting positioning data from a transmitter of the calibration system to a remote location.

26. The method of claim 1 further comprising:

determining the orientation of the calibration sensor using an orientation sensor of the calibration system; and

communicating the orientation from a transmitter of the calibration system to a remote location.

27. The method of claim 1, wherein the calibration system is programmed with the test pattern prior to the placing.

30. The method of claim 6, wherein the panel of known trans-spectral reflectance is a white panel.

13. A calibration system that can be placed a distance from an object that is in a monitored environment from which imaging data is to be collected by a sensor and used for correcting imaging data received from the sensor, in an environment comparable to the monitored environment, the calibration system and the object being sufficiently far from the sensor so that imaging data collected by the sensor is distorted by atmospheric variables, the calibration system comprising:

a calibration array that emits a test pattern having geometric, temporal, and electromagnetic characteristics, the calibration array having a plurality of emission points, each emission point including at least one emission source that emits in a region of the electromagnetic spectrum;

a control unit operatively connected to the calibration array that provides test pattern commands to the calibration array in order to cause the calibration array to emit the test pattern; and

a communication system operatively connected to the control unit that communicates data from the calibration system to a remote location.

14. The calibration system of claim 13, wherein the test pattern is a trans-spectral test pattern.

15. The calibration system of claim 13, wherein each emission point comprises a plurality of emission sources, and each emission source emits with a different electromagnetic signature.

16. The calibration system of claim 13, wherein the calibration array further comprises a non-emitting surface, and each emission point is located at a known location on the surface.

17. The calibration system of claim 16, wherein the surface is non-reflective.

18. The calibration system of claim 16, wherein the calibration array further comprises a panel of known trans-spectral reflectance.

19. The calibration system of claim 13, wherein the communication system includes a communications receiver that receives test pattern commands from a remote location and provides them to the control unit.

20. The calibration system of claim 13, further comprising built in test equipment operatively connected to the control unit that collects test pattern data when the calibration array that emits the trans-spectral test pattern, the test pattern data including the state of each emission point.

21. The calibration system of claim 20, wherein the data communicated from the calibration system to the remote location includes the test pattern data.

22. The calibration system of claim 13, further comprising an environmental monitor operatively connected to the control unit that collects environmental data regarding the environment in which the calibration system is placed.

23. The calibration system of claim 22, wherein the data communicated from the calibration system to the remote location includes the environmental data.

24. The calibration system of claim 13, further comprising a GPS receiver operatively connected to the control unit that collects global positioning signals.

25. The calibration system of claim 24, wherein the data communicated from the calibration system to the remote location includes positioning data.

28. The calibration system of claim 13 further comprising an orientation sensor connected to the control unit.

29. The calibration system of claim 13, wherein the test pattern is stored in the control unit.

31. The calibration system of claim 13, wherein the panel of known trans-spectral reflectance is a white panel.