Methods and related apparatus for generating thermographic survey images

• US 5,818,951 A
• Filed: 10/13/1995
• Issued: 10/06/1998
• Est. Priority Date: 10/13/1995
• Status: Expired due to Term

• Current Assignee: Stanley W. Mcdougall
• Original Assignee: Infrared Service Corporation
• Inventors: Schivley, James Dale
• Primary Examiner(s): Bost, Dwayne
• Assistant Examiner(s): JOHNSON, BRIAN
• Application Number:
  US08/543,189
• Time in Patent Office: 1,089 Days
• Field of Search: 348/32, 348/144, 348/164, 348/184, 348/64, 348/25, 348/29, 382/270, 382/284, 382/294, 382/298, 382/311, 382/100, 395/135, 395/133, 358/183, 358/139
• US Class Current: 382/100
• CPC Class Codes: G06T 5/50 using two or more images, e.g. averaging or subtraction
• CPC Class Codes: G06V 10/987 with the intervention of an operator
• CPC Class Codes: G06V 20/13 Satellite images

Abstract

A method for generating a thermographic output survey image, such as for a building roof moisture survey or concrete delamination survey, using a processor and a display screen operatively connected thereto includes the steps of: obtaining an aerial thermographic survey image and an aerial visual image of a survey area; loading the thermographic and visual images into the processor; displaying on the display screen the thermographic image superimposed on the visual image; selectively reducing an opacity of the displayed thermographic survey image to reveal visible features of the underlying displayed visual image; and observing and selectively removing false anomaly thermographic image portions from the displayed thermographic survey image based upon features of the underlying visual image to thereby generate an accurate and high quality output thermographic survey image. If a hard copy of the output survey image is desired, the method may also include the step of printing the output thermographic survey image. Apparatus aspects of the invention are also disclosed.

Claims

1. A method for generating an output thermographic survey image using a processor and a display screen operatively connected thereto, the method comprising the steps of:

obtaining an aerial thermographic survey image of a survey area;

obtaining an aerial visual image of the survey area;

loading the aerial thermographic survey image and the aerial visual image into the processor;

displaying on the display screen the aerial thermographic survey image superimposed on the aerial visual image;

selectively reducing an opacity of the displayed thermographic survey image to reveal visible features of the underlying displayed visual image; and

observing and selectively removing false anomaly thermographic image portions from the displayed thermographic survey image based upon features of the underlying displayed visual image to thereby generate an output thermographic survey image.

2. A method according to claim 1 further comprising the step of printing the output thermographic survey image.

3. A method according to claim 1 wherein the displayed thermographic survey image comprises a plurality of pixels, and further comprising the steps of:

generating an intensity histogram of the plurality of pixels of the displayed thermographic survey image; and

defining a threshold to select only pixels having an intensity above the threshold to be displayed on the display screen.

4. A method according to claim 3 wherein the step of obtaining an aerial thermographic survey image comprises obtaining an aerial thermographic survey image of a building roof for a roof moisture survey;

and wherein the step of defining a threshold comprises defining same to identify moisture anomalies in the building roof.

5. A method according to claim 3 wherein the step of obtaining an aerial thermographic survey image comprises obtaining an aerial thermographic survey image of a concrete structure for a concrete delamination survey;

and wherein the step of defining a threshold comprises defining same to identify delamination anomalies in the concrete structure.

6. A method according to claim 1 wherein the step of obtaining an aerial thermographic survey image comprises obtaining an aerial thermographic survey image of a building roof for a roof moisture survey;

and further comprising the steps of;

conducting roof core sample moisture tests; and

adding indicia relating to the core sample moisture tests to the output thermographic survey image.

7. A method according to claim 1 further comprising the steps of obtaining, processing and adding information from a second survey image of a different type to the output thermographic survey image.

8. A method according to claim 7 wherein the second survey image is based upon one of surface penetrating radar sensing, and nuclear moisture sensing.

9. A method according to claim 1 wherein the step of displaying comprises the steps of:

observing and relatively scaling the displayed aerial thermographic survey image and the displayed aerial visual image to be a same scale on the display screen; and

aligning the scaled displayed aerial thermographic survey image and the scaled displayed visual image to be in registry with one another.

10. A method according to claim 9 wherein the step of aligning comprises selecting corresponding points on the scaled displayed thermographic survey image and the scaled displayed visual image and repositioning the selected points to overlie one another.

11. A method according to claim 1 further comprising the step of converting the aerial thermographic survey image and the aerial visual image into respective image data.

12. A method according to claim 1 further comprising the step of inverting the displayed thermographic survey image.

13. A method according to claim 1 further comprising the step of adding color to the displayed thermographic survey image.

14. A method according to claim 1 wherein the step of obtaining a visual image of the survey area comprises the step of taking an aerial photograph of the survey area.

15. A method according to claim 14 further comprising the step of converting the aerial photograph of the survey area into digital format and storing same on a CDROM.

16. A method according to claim 1 wherein the step of obtaining a visual image of the survey area comprises the step of obtaining a plan view drawing of the survey area.

17. A method according to claim 1 wherein the step of obtaining a thermographic survey image of the survey area comprises the step of taking an aerial forward looking infrared radar (FLIR) videotape of the survey area and selecting a frame from the videotape at a substantially vertical relationship to the survey area.

18. A method according to claim 1 further comprising the step of adding indicia to the output thermographic survey image.

19. A method for generating an output building roof moisture survey image using a processor and a display screen operatively connected thereto, the method comprising the steps of:

obtaining an aerial thermographic survey image of a building roof defining a survey area;

obtaining an aerial visual image of the survey area;

loading the aerial thermographic survey image and the aerial visual image into the processor;

displaying on the display screen the aerial thermographic survey image superimposed on the aerial visual image;

processing the displayed thermographic survey image to generate an output building roof moisture survey image;

selectively reducing an opacity of the displayed thermographic survey image to reveal visible features of the underlying displayed visual image; and

observing and selectively removing false anomaly thermographic image portions from the displayed thermographic survey image based upon features of the underlying displayed visual image to thereby generate the output building roof moisture survey image.

20. A method according to claim 19 further comprising the step of printing the output building roof moisture survey image.

21. A method according to claim 19 wherein the displayed thermographic survey image comprises a plurality of pixels, and where the step of processing further comprises:

generating an intensity histogram of the plurality of pixels of the displayed thermographic survey image; and

defining a threshold to select only pixels having an intensity above the threshold to be displayed on the display screen representative of moisture anomalies in the building roof.

22. A method according to claim 19 further comprising the steps of:

conducting roof core sample moisture tests; and

adding indicia relating to the core sample moisture tests to the output building roof moisture survey image.

23. A method according to claim 19 further comprising the steps of obtaining, processing and adding information from a second survey image of a different type to the output building roof moisture survey image.

24. A method according to claim 23 wherein the second survey image is based upon nuclear moisture sensing.

25. A method according to claim 19 wherein the step of processing further comprises inverting the displayed thermographic survey image.

26. A method according to claim 19 wherein the step of processing further comprises adding color to the displayed thermographic survey image.

27. A method according to claim 19 wherein the step of obtaining a visual image of the survey area comprises the step of taking an aerial photograph of the survey area.

28. A method according to claim 19 further comprising the step of adding indicia to the output building roof moisture survey image.

29. A method for generating an output concrete structure delamination survey image using a processor and a display screen operatively connected thereto, the method comprising the steps of:

obtaining an aerial thermographic survey image of a concrete structure defining a survey area;

obtaining an aerial visual image of the survey area;

loading the aerial thermographic survey image and the aerial visual image into the processor;

displaying on the display screen the aerial thermographic survey image superimposed on the aerial visual image;

processing the displayed thermographic survey image to generate an output concrete structure delamination survey image;

selectively reducing an opacity of the displayed thermographic survey image to reveal visible features of the underlying displayed visual image; and

observing and selectively removing false anomaly thermographic image portions from the displayed thermographic survey image based upon features of the underlying displayed visual image to thereby generate the output concrete structure delamination survey image.

30. A method according to claim 29 further comprising the step of printing the output concrete structure delamination survey image.

31. A method according to claim 29 wherein the displayed thermographic survey image comprises a plurality of pixels, and wherein the step of processing further comprises:

generating an intensity histogram of the plurality of pixels of the displayed thermographic survey image; and

defining a threshold to select only pixels having an intensity above the threshold to be displayed on the display screen representative of delamination anomalies in the concrete structure.

32. A method according to claim 29 further comprising the steps of obtaining, processing and adding information from a second survey image of a different type to the output concrete structure delamination survey image.

33. A method according to claim 29 wherein the step of processing further comprises adding color to the displayed thermographic survey image.

34. A method according to claim 29 wherein the step of obtaining a visual image of the survey area comprises the step of taking an aerial photograph of the survey area.

35. A method according to claim 29 further comprising the step of adding indicia to the output concrete structure survey image.

36. An apparatus for generating an output thermographic survey image comprising:

a processor and a display screen operatively connected thereto, said processor comprising

loading means for loading the aerial thermographic survey image and the aerial visual image;

displaying means for displaying on the display screen the aerial thermographic survey image superimposed on the aerial visual image;

opacity control means for permitting selectively reducing an opacity of the displayed thermographic survey image to reveal visible features of the underlying displayed visual image; and

edit means for permitting selectively removing false anomaly thermographic image portions from the displayed thermographic survey image based upon features of the underlying displayed visual image to thereby generate an output thermographic survey image.

37. An apparatus according to claim 36 wherein said displaying means comprises means for displaying the thermographic survey image as a plurality of pixels;

and further comprising threshold means for generating an intensity histogram of the plurality of pixels of the displayed thermographic survey image and permitting selection of a threshold to select only pixels having an intensity above the threshold to be displayed on the display screen.

38. An apparatus according to claim 36 further comprising survey adding means for processing and adding information from a second survey image of a different type to the output thermographic survey image.

39. An apparatus according to claim 36 further comprising indicia adding means for permitting adding indicia to the output thermographic survey image.