METHOD AND SYSTEM FOR PERFORMING X-RAY INSPECTION OF A PRODUCT AT A SECURITY CHECKPOINT USING SIMULATION

• US 20110051996A1
• Filed: 06/09/2009
• Published: 03/03/2011
• Est. Priority Date: 02/10/2009
• Status: Active Grant

• Current Assignee: Vanderlande Industries BV (VIVE BV)
• Original Assignee: Optosecurity Inc.
• Inventors: Bourbeau, Eric, Perron, Luc, Gudmundson, Dan
• Granted Patent: US 8,831,331 B2
• Time in Patent Office: Days
• US Class Current: 382/100
• CPC Class Codes: G01N 2001/024 passengers or luggage
• CPC Class Codes: G01N 2223/637 liquid
• CPC Class Codes: G01N 23/083 the radiation being X-rays
• CPC Class Codes: G01N 23/10 the material being confined in a container, e.g. in a luggage X-ray scanners
• CPC Class Codes: G01N 9/24 by observing the transmission of wave or particle radiation through the material
• CPC Class Codes: G01V 5/226 using tomography
• CPC Class Codes: G06T 2207/10116 X-ray image
• CPC Class Codes: G06T 2207/30232 Surveillance
• CPC Class Codes: G06T 7/60 Analysis of geometric attributes

Abstract

A method, an apparatus and a system are provided for deriving a characteristic of a product using X-rays. X-ray image data associated with the product is received, the X-ray image data being derived by performing an X-ray scan of the product using an X-ray imaging apparatus and conveying attenuation information resulting from interaction of X-rays with the product. A response of a reference product to X-rays is then simulated to generate simulated X-ray image data. The simulated X-ray image data and the received X-ray image data are then processed to derive one or more characteristics of the product. Information conveying the derived characteristic of the product is then released. In a specific implementation, the product is a liquid product comprised of a bottle at least partially filled with liquid and the derived characteristic of the liquid product is a threat status assessment associated with the liquid in the bottle. In another aspect, a simulation engine for simulating interactions between X-rays and objects is also provided.

Claims

1. ) A method for assessing a threat status of a liquid product under inspection at a security checkpoint, the liquid product being comprised of a bottle holding a liquid, wherein the bottle is at least partially filled with liquid, the method comprising:

a) receiving X-ray image data associated with the liquid product, the X-ray image data being derived by performing an X-ray scan of the liquid product using an X-ray imaging apparatus and conveying attenuation information resulting from interaction of X-rays with the liquid product;

b) simulating a response of a reference liquid product to X-rays to generate simulated X-ray image data;

c) processing the simulated X-ray image data and the received X-ray image data to determine the threat status of the liquid product;

d) releasing information conveying the determined threat status of the liquid product.

2. ) A method as defined in claim 1, wherein the reference liquid product is comprised of a reference bottle and a reference liquid.

3. ) A method as defined in claim 1, wherein said method comprises:

a) deriving a virtual model of the reference liquid product; and

b) using the virtual model of the reference liquid product in simulating the response of the reference liquid product to X-rays to generate the simulated X-ray image data.

4. ) A method as defined in claim 3, wherein the virtual model of the reference liquid product conveys 3-D geometric information associated with the reference liquid product.

5. ) A method as defined in claim 3, wherein the virtual model of the reference liquid product conveys location information associated with a meniscus formed by liquid.

6. ) A method as defined in claim 3, wherein deriving the virtual model of the reference liquid product comprises:

a) generating a set of candidate virtual models;

b) selecting at least one virtual model from the set of candidate virtual models at least in part by simulating responses to X-rays of the candidate virtual models in said set of candidate virtual models.

7. ) A method as defined in claim 6, wherein the candidate virtual models are generated at least in part by:

a) processing the X-ray image data associated with the liquid product under inspection to derive geometric information associated with the liquid product;

b) using the derived geometric information associated with the liquid product to generate the set of candidate virtual models.

8. ) A method as defined in claim 6, wherein generating the set of candidate virtual models includes generating virtual models of bottles having cross-sectional shapes selected from the set consisting of a generally circular shape, a generally elliptical shape, a generally rectangular shape and a generally square shape.

9. ) A method as defined in claim 6, wherein the set of candidate virtual models includes candidate virtual models associated with different levels of fill.

10. ) A method as defined in claim 6, wherein the set of candidate virtual models includes candidate virtual models associated to different liquid substances from a set of reference liquid substances.

11. ) A method as defined in claim 10, wherein the set of reference liquid substances includes at least one reference liquid substance that constitutes a threat.

12. ) A method as defined in claim 6, wherein selecting at least one virtual model from the set of candidate virtual models comprises:

a) simulating responses to X-rays of the candidate virtual models in said set of candidate virtual models to obtain simulated X-ray data;

b) effecting a comparison between the simulated X-ray data and the X-ray data associated to the liquid product under inspection;

c) selecting the at least one virtual model from the set of candidate virtual models as the virtual model of the reference liquid product at least in part based on the comparison between the simulated X-ray data and the X-ray data associated to the liquid product under inspection.

13. ) A method as defined in claim 1, wherein the X-ray image data associated with the liquid product is obtained using a multi-view X-ray machine, said X-ray image data conveying a first X-ray image of the liquid product taken by subjecting the liquid product to X-rays in a first orientation and a second X-ray image of the liquid product taken by subjecting the liquid product to X-rays in a second orientation.

14. ) A method as defined in claim 13, wherein said method comprises:

a) deriving a virtual model of the reference liquid product based at least in part on the first X-ray image and the second X-ray image;

b) using the virtual model of the reference liquid product in simulating responses of the reference liquid product to X-rays in the first orientation to generate simulated X-ray image data.

15. ) A method as defined in claim 1, said method comprising:

a) placing the liquid product under inspection in a tray;

b) introducing the tray and the liquid product in a scanning area of the X-ray imaging apparatus.

16. ) A method as defined in claim 15, wherein the bottle holding the liquid has a top extremity and a bottom extremity, the method comprising positioning the bottle to induce a meniscus formed by the liquid in the bottle to migrate toward one of the extremities while performing the X-ray inspection of the liquid product.

17. ) A computer readable storage medium storing a program element suitable for execution by a computing apparatus for assessing a threat status of a liquid product under inspection at a security checkpoint, the liquid product being comprised of a bottle holding a liquid, wherein the bottle is at least partially filled with liquid, said computing apparatus comprising:

a) a memory unit;

b) a processor operatively connected to said memory unit, said program element when executing on said processor being operative for implementing a method comprising;

i) receiving X-ray image data associated with the liquid product, the X-ray image data being derived by performing an X-ray scan of the liquid product using an X-ray imaging apparatus and conveying attenuation information resulting from interaction of X-rays with the liquid product;

ii) simulating a response of a reference liquid product to X-rays to generate simulated X-ray image data;

iii) processing the simulated X-ray image data and the received X-ray image data to determine the threat status of the liquid product;

iv) releasing information conveying the determined threat status of the liquid product.

18. ) An apparatus for assessing a threat status of a liquid product under inspection at a security checkpoint, the liquid product being comprised of a bottle holding a liquid, wherein the bottle is at least partially filled with liquid, said apparatus comprising an input, a processing unit and an output, said apparatus comprising:

i) an input for receiving X-ray image data associated with the liquid product, the X-ray image data being derived by performing an X-ray scan of the liquid product using an X-ray imaging apparatus and conveying attenuation information resulting from interaction of X-rays with the liquid product;

ii) a processor in communication with said input, said processor being programmed for;

(1) simulating a response of a reference liquid product to X-rays to generate simulated X-ray image data;

(2) processing the simulated X-ray image data and the received X-ray image data to determine the threat status of the liquid product;

iii) an output for releasing information conveying the determined threat status of the liquid product.

19. ) A system suitable for assessing a threat status of a liquid product under inspection at a security checkpoint, the liquid product being comprised of a bottle holding a liquid, wherein the bottle is at least partially filled with liquid, said system comprising:

a) an inspection device for performing an X-ray inspection on the liquid product using penetrating radiation to generate X-ray image data associated with the liquid product under inspection;

b) an apparatus as defined in claim 18 for assessing the threat status of the liquid product;

c) a display screen in communication with the output of said apparatus for visually conveying to an operator the assessed threat status of the liquid product based on information released by the apparatus.

20. ) A system as defined in claim 19, wherein the inspection device is a multi-view X-ray machine.

21. ) A system as defined in claim 19, wherein the inspection device is a single-view X-ray machine.

22. ) (canceled)

23. ) A method for deriving a characteristic of a product using X-rays, the method comprising:

a) receiving X-ray image data associated with the product, the X-ray image data being derived by performing an X-ray scan of the product using an X-ray imaging apparatus and conveying attenuation information resulting from interaction of X-rays with the product;

b) simulating a response of a reference product to X-rays to generate simulated X-ray image data;

c) processing the simulated X-ray image data and the received X-ray image data to derive the characteristic of the product;

d) releasing information conveying the derived characteristic of the product.

24. ) A method as defined in claim 23, where the characteristic is selected from the set consisting of material density, type of material, threat status, linear attenuation coefficient and effective atomic number (Z_eff number).

25. ) A method as defined in claim 23, said method comprising:

a) deriving a virtual model of the reference product; and

b) using the virtual model of the reference product in simulating the response of the reference product to X-rays to generate the simulated X-ray image data.

26. ) A method as defined in claim 25, wherein deriving the virtual model of the reference product comprises:

a) generating a set of candidate virtual models;

b) selecting at least one virtual model from the set of candidate virtual models at least in part by simulating responses to X-rays of the candidate virtual models in said set of candidate virtual models.

27. ) A method as defined in claim 26, wherein the candidate virtual models are generated at least in part by:

a) processing the X-ray image data associated with the product under inspection to derive geometric information associated with the product;

b) using the derived geometric information associated with the product to generate the set of candidate virtual models.

28. ) A method as defined in claim 26, wherein the set of candidate virtual models includes candidate virtual models associated to different substances from a set of reference substances.

29. ) A method as defined in claim 26, wherein selecting at least one virtual model from the set of candidate virtual models comprises:

a) simulating responses to X-rays of the candidate virtual models in said set of candidate virtual models to obtain simulated X-ray data;

b) effecting a comparison between the simulated X-ray data and the X-ray data associated to the product under inspection;

c) selecting the at least one virtual model from the set of candidate virtual models as the virtual model of the reference product at least in part based on the comparison between the simulated X-ray data and the X-ray data associated to the product under inspection.

30. ) A method as defined in claim 23, wherein the X-ray image data associated with the product is obtained using a multi-view X-ray machine, said X-ray image data conveying a first X-ray image of the product taken by subjecting the product to X-rays in a first orientation and a second X-ray image of the product taken by subjecting the product to X-rays in a second orientation.

31. ) A method as defined in claim 30, wherein said method comprises:

a) deriving a virtual model of the reference product based at least in part on the first X-ray image and the second X-ray image;

b) using the virtual model of the reference product in simulating responses of the reference product to X-rays in the first orientation to generate simulated X-ray image data.

32. ) A computer readable storage medium storing a program element suitable for execution by a computing apparatus for deriving a characteristic of a product based in part on an X-ray image of the product, said computing apparatus comprising:

a) a memory unit;

b) a processor operatively connected to said memory unit, said program element when executing on said processor being operative for;

i) receiving X-ray image data associated with the product, the X-ray image data being derived by performing an X-ray scan of the product using an X-ray imaging apparatus and conveying attenuation information resulting from interaction of X-rays with the product;

ii) simulating a response of a reference product to X-rays to generate simulated X-ray image data;

iii) processing the simulated X-ray image data and the received X-ray image data to derive the characteristic of the product;

iv) releasing information conveying the derived characteristic of the product.

v).

33. ) (canceled)

34. ) (canceled)

35. ) (canceled)

36. ) (canceled)

37. ) An apparatus for simulating a response of a reference product to X-rays, said apparatus comprising a processor for processing characterization data associated with a reference product to generate simulated X-ray image data associated with the reference product by modelling interactions between X-rays and the reference product.

38. ) An apparatus as defined in claim 37, wherein the characterization data conveys:

i) shape information associated with the reference product; and

ii) material type information associated with the reference product.

39. ) An apparatus as defined in claim 38, wherein the characterization data conveys positioning information for positioning the reference product relative to a source of X-rays.

40. ) (canceled)

41. ) (canceled)

42. ) An apparatus for simulating a response of a reference product to X-rays, said apparatus comprising:

a) a simulation engine for processing characterization data associated with the reference product to model interactions between X-rays and the reference product and generate simulated X-ray data, the characterization data conveying;

i) shape information associated with the reference product; and

ii) material type information associated with the reference product;

b) an output in communication with said simulation engine for releasing the simulated X-ray image data.

43. ) An apparatus as defined in claim 42, wherein said characterization data associated with the reference product further conveys positioning information for positioning the reference product relative to a source of X-rays.

44. ) An apparatus as defined in claim 42, wherein the characterization data associated with the reference product is derived at least in part based on geometric information associated with a real product.

45. ) An apparatus as defined in claim 42, wherein said apparatus comprises an input for receiving the characterization data associated with the reference product and wherein said simulation engine is in communication with said input.

46. ) An apparatus as defined in claim 44, wherein the characterization data associated with the reference product is derived from X-ray image data associated with the real product, said X-ray image data being derived by performing an X-ray scan of the real product using an X-ray imaging apparatus, said X-ray image data conveying attenuation information resulting from interaction of X-rays with the real product.

47. ) An apparatus as defined in claim 44, wherein said apparatus comprises a product characterisation module for:

a) processing X-ray image data associated to the real product to derive the geometric information associated with the real product;

b) derive the characterization data associated with the reference product based in part on the geometric information associated with the real product.

48. ) An apparatus as defined in claim 47, wherein said apparatus comprises an input for receiving the X-ray image data associated with the real product for processing by the product characterisation module, said X-ray image data being derived by performing an X-ray scan of the real product using an X-ray imaging apparatus, said X-ray image data conveying attenuation information resulting from interaction of X-rays with the real product.

49. ) A method for deriving a characteristic of a product, said method comprising:

a) processing characterization data associated with the product to generate simulated X-ray image data by modelling interactions between X-rays and the product;

b) processing the simulated X-ray image data to derive the characteristic of the product;

c) releasing data conveying the derived characteristic of the product.

50. ) A method as defined in claim 49, said method comprising receiving the characterization data associated with the product.

51. ) A method as defined in claim 49, wherein the characterization data conveys:

i) shape information associated with the product; and

ii) positioning information for positioning the product relative to a source of X-rays.

52. ) A method as defined in claim 49, wherein the characterization data is derived from X-ray image data associated with the product, the X-ray image data associated with the product being derived by performing an X-ray scan of the product using an X-ray imaging apparatus and conveying attenuation information resulting from interaction of X-rays with the product.

53. ) A method as defined in claim 52, wherein the characteristic of the product is derived at least in part by comparing the X-ray image data associated with the product to the simulated X-ray image data.

54. ) (canceled)