USER INTERFACE FOR USE IN SECURITY SCREENING PROVIDING IMAGE ENHANCEMENT CAPABILITIES AND APPARATUS FOR IMPLEMENTING SAME

• US 20080240578A1
• Filed: 03/30/2007
• Published: 10/02/2008
• Est. Priority Date: 03/30/2007
• Status: Active Grant

• Current Assignee: Vanderlande APC Inc (Toyota Motor Corporation)
• Original Assignee: Optosecurity Inc. (Toyota Motor Corporation)
• Inventors: Gudmundson, Dan, Perron, Luc
• Granted Patent: US 8,494,210 B2
• Time in Patent Office: Days
• US Class Current: 382/218
• CPC Class Codes: G01V 5/271 using a network, e.g. a remote expert, accessing remote data or the like
• CPC Class Codes: G06V 10/255 Detecting or recognising potential candidate objects based on visual cues, e.g. shapes
• CPC Class Codes: G06V 20/52 Surveillance or monitoring of activities, e.g. for recognising suspicious objects recognising microscopic objects G06V20/69

Abstract

An apparatus, method and system for facilitating visual identification of a prohibited object in an image during security screening are provided. Data derived from an apparatus that scans the receptacle with penetrating radiation conveying an image of the contents of a receptacle is received. Information from an automated threat detection processor is also received and indicates an area of interest in the image potentially containing a prohibited object. The image is then processed to generate an enhanced image. In a first example, portions of the enhanced image outside the area of interest are visually de-emphasized. In a second example, features appearing inside the area of interest are visually emphasized. The enhanced image is then displayed on a display device. Optionally, thumbnail images associated with previously screened receptacles are displayed and a user is enabled to select one or more thumbnail images. An enhanced image corresponding to the selected thumbnail image is then displayed. In alternative implementations, an apparatus, method and system for use in screening a person for facilitating visual identification of a prohibited object thereon is provided.

Claims

1. A method for facilitating visual identification of a prohibited object in an image during security screening, said method comprising:

a. receiving data conveying an image of the contents of a receptacle derived from an apparatus that scans the receptacle with penetrating radiation;

b. receiving information from an automated threat detection processor indicating an area of interest in the image potentially containing a prohibited object;

c. processing the image to generate an enhanced image in which portions outside the area of interest are visually de-emphasized;

d. displaying the enhanced image on a display device.

2. A method as defined in claim 1, wherein processing the image includes modifying portions of the image outside the area of interest.

3. A method as defined in claim 1, wherein processing the image includes reducing contrasts between feature information appearing in portions of the image outside the area of interest and background information appearing in portions of the image outside the area of interest.

4. A method as defined in claim 1, wherein processing the image includes attenuating portions of the image outside the area of interest.

5. A method as defined in claim 1, wherein processing the image includes replacing portions of the image outside the area of interest with a pre-determined visual pattern.

6. A method as defined in claim 1, wherein processing the image includes overlaying portions of the image outside the area of interest with a pre-determined visual pattern.

7. A method as defined in claim 1, wherein the image includes color information, wherein processing the image includes modifying color information associated to features of the image appearing outside the area of interest.

8. A method as defined in claim 7, wherein processing the image includes converting portions of the image outside the area of interest into grayscale.

9. A method as defined in claim 1, wherein processing the image includes reducing a resolution associated to portions of the image outside the area of interest.

10. A method as defined in claim 1, said method further comprising modifying portions of areas surrounding the area of interest to generate the enhanced image.

11. A method as defined in claim 10, wherein modifying portions of areas surrounding the area of interest includes applying a blurring function to portions of areas surrounding the area of interest.

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

a. receiving information from an automated threat detection processor indicating a plurality of areas of interest in the image potentially containing respective prohibited objects;

b. processing the image to generate the enhanced image in which portions outside the areas of interest are visually de-emphasized.

13. A method as defined in claim 1, wherein said method comprises shrinking portions of the image outside the area of interest such that at least some features of the enhanced image located inside the area of interest appear on a larger scale than features in portions of the enhanced image located outside the area of interest.

14. A method as defined in claim 2, wherein portions of the enhanced image inside the area of interest are visually emphasized.

15. A method as defined in claim 14, wherein processing the image includes modifying portions of the image inside the area of interest to derive the enhanced image.

16. A method as defined in claim 14, wherein processing the image includes increasing contrasts between feature information appearing in portions of the image inside the area of interest and background information appearing in portions of the image inside the area of interest.

17. A method as defined in claim 14, wherein processing the image includes overlaying portions of the image inside the area of interest with a pre-determined visual pattern.

18. A method as defined in claim 14, wherein processing the image includes modifying color information associated to features of the image appearing inside the area of interest.

19. A method as defined in claim 15, wherein said method comprises enlarging a portion of the image inside the area of interest such that at least some features of the enhanced image located inside the area of interest appear on a larger scale than features in portions of the enhanced image located outside the area of interest.

20. A method as defined in claim 1, said method comprising providing a user control allowing a user to select either one of the image conveyed by the data received and the enhanced image to be displayed on the display device.

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

a. providing a user control allowing a user to select a level of enhancement from a set of possible levels of enhancement;

b. processing the image to generate the enhanced image such that portions outside the area of interest in the enhanced image are visually de-emphasized at least in part based on the selected level of enhancement.

22. A method as defined in claim 14, said method comprising:

a. providing a user control allowing a user to select a level of enhancement from a set of possible levels of enhancement;

b. processing the image to generate the enhanced image such that portions inside the area of interest in the enhanced image are visually emphasized at least in part based on the selected level of enhancement.

23. A method as defined in claim 22, wherein said user control is a first user control and the selected level of enhancement is a first selected level of enhancement, said method comprising:

a. providing a second user control allowing a user to select a second level of enhancement from a set of possible levels of enhancement;

b. processing the image to generate the enhanced image such that portions inside the area of interest in the enhanced image are visually emphasized at least in part based on the selected second level of enhancement.

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

a. providing a user control allowing a user to select a level of enlargement from a set of possible levels of enlargement;

b. processing the image to generate the enhanced image such that portions inside the area of interest are enlarged at least in part based on the selected level of enlargement such that features of the portion of the enhanced image inside the area of interest appear on a larger scale than features in portions of the enhanced image outside the area of interest.

25. An apparatus for implementing a user interface module for facilitating visual identification of a prohibited object in an image during security screening, said apparatus comprising:

a. a first input for receiving data conveying an image of the contents of a receptacle derived from an apparatus that scans the receptacle with penetrating radiation;

b. a second input for receiving information from an automated threat detection processor indicating an area of interest in the image potentially containing a prohibited object;

c. a processing unit in communication with the first input and the second input, said processing unit being operative for implementing the user interface module, said user interface module being adapted for;

i. processing the image to generate an enhanced image in which portions outside the area of interest are visually de-emphasized;

ii. displaying the enhanced image on a display module.

26. An apparatus as defined in claim 25, wherein said user interface module is operative for modifying portions of the image outside the area of interest during processing of the image to generate the enhanced image.

27. An apparatus as defined in claim 25, wherein processing the image includes reducing contrasts between feature information appearing in portions of the image outside the area of interest and background information appearing in portions of the image outside the area of interest.

28. An apparatus as defined in claim 25, wherein processing the image includes attenuating portions of the image outside the area of interest.

29. An apparatus as defined in claim 25, wherein processing the image includes replacing portions of the image outside the area of interest with a pre-determined visual pattern.

30. An apparatus as defined in claim 25, wherein processing the image includes overlaying portions of the image outside the area of interest with a pre-determined visual pattern.

31. An apparatus as defined in claim 25, wherein the image includes color information, wherein processing the image includes modifying color information associated to features of the image appearing outside the area of interest.

32. An apparatus as defined in claim 31, wherein processing the image includes converting portions of the image outside the area of interest into grayscale.

33. An apparatus as defined in claim 25, wherein processing the image includes reducing a resolution associated to portions of the image outside the area of interest.

34. An apparatus as defined in claim 25, wherein said user interface module is adapted for modifying portions of areas surrounding the area of interest to generate the enhanced image.

35. An apparatus as defined in claim 34, wherein modifying portions of areas surrounding the area of interest includes applying a blurring function to portions of areas surrounding the area of interest.

36. An apparatus as defined in claim 25, wherein processing the image includes shrinking portions of the image outside the area of interest such that at least some features of the enhanced image located inside the area of interest appear on a larger scale than features in portions of the enhanced image located outside the area of interest.

37. An apparatus as defined in claim 26, wherein portions of the enhanced image inside the area of interest are visually emphasized.

38. An apparatus as defined in claim 37, wherein processing the image includes modifying portions of the image inside the area of interest to derive the enhanced image.

39. An apparatus as defined in claim 37, wherein processing the image includes increasing contrasts between feature information appearing in portions of the image inside the area of interest and background information appearing in portions of the image inside the area of interest.

40. An apparatus as defined in claim 37, wherein processing the image includes overlaying portions of the image inside the area of interest with a pre-determined visual pattern.

41. An apparatus as defined in claim 37, wherein processing the image includes modifying color information associated to features of the image appearing inside the area of interest.

42. An apparatus as defined in claim 38, wherein said user interface module is adapted for enlarging a portion of the image inside the area of interest such that features located in the portion of the enhanced image inside the area of interest appear on a larger scale than features located in portions of the enhanced image outside the area of interest.

43. An apparatus as defined in claim 25, wherein said user interface module is adapted for displaying a user control allowing a user to select either one of the image conveyed by the data received and the enhanced image to be displayed on the display device.

44. An apparatus as defined in claim 25, wherein said user interface module is adapted for:

a. displaying a user control allowing a user to select a level of enhancement from a set of possible levels of enhancement;

b. processing the image to generate the enhanced image such that portions outside the area of interest in the enhanced image are visually de-emphasized at least in part based on the selected level of enhancement.

45. An apparatus as defined in claim 25, wherein said user interface module is adapted for:

a. displaying a user control allowing a user to select a level of enhancement from a set of possible levels of enhancement;

b. processing the image to generate the enhanced image such that portions inside the area of interest in the enhanced image are visually emphasized at least in part based on the selected level of enhancement.

46. An apparatus as defined in claim 44, wherein said user control is a first user control and the selected level of enhancement is a first selected level of enhancement, said user interface module being further adapted for:

a. displaying a second user control allowing a user to select a second level of enhancement from a set of possible levels of enhancement;

b. processing the image to generate the enhanced image such that portions inside the area of interest in the enhanced image are visually emphasized at least in part based on the selected second level of enhancement.

47. An apparatus as defined in claim 25, wherein said user interface module is adapted for:

a. displaying a user control allowing a user to select a level of enlargement from a set of possible levels of enlargement;

b. processing the image to generate the enhanced image such that portions inside the area of interest are enlarged at least in part based on the selected level of enlargement such that features of the portion of the enhanced image inside the area of interest appear on a larger scale than features in portions of the enhanced image outside the area of interest.

48. A computer readable storage medium storing a program element suitable for execution by a CPU, said program element implementing a graphical user interface module for facilitating visual identification of a prohibited object in the image during security screening, said graphical user interface module being adapted for:

a. receiving data conveying an image of the contents of a receptacle derived from an apparatus that scans the receptacle with penetrating radiation;

b. receiving information from an automated threat detection processor indicating an area of interest in the image potentially containing a prohibited object;

c. processing the image to generate an enhanced image in which portions outside the area of interest are visually de-emphasized;

d. displaying the enhanced image on a display device.

49. A system for detecting the presence of one or more prohibited objects in a receptacle, comprising:

a. an image generation apparatus suitable for scanning a receptacle with penetrating radiation to generate data conveying an image of contents of the receptacle;

b. an automated threat detection processor in communication with said image generation apparatus, said automated threat detection processor being adapted for processing the image to identify an area of interest in the image potentially containing a prohibited object;

c. a display module;

d. an apparatus in communication with said image generation apparatus, said automated threat detection processor and said display module, said apparatus implementing a user interface module for facilitating visual identification of a prohibited object in an image during security screening, said apparatus comprising;

i. a first input for receiving the data conveying the image of the contents of the receptacle;

ii. a second input for receiving information indicating the area of interest in the image;

iii. a processing unit in communication with the first input and the second input, said processing unit being operative for implementing the user interface module, said user interface module being adapted for;

1. processing the image to generate an enhanced image in which portions outside the area of interest are visually de-emphasized;

2. displaying the enhanced image on said display module.

50. A client-server system for implementing a graphical user interface module for facilitating visual identification of a prohibited object in an image during security screening, said client-server system comprising a client system and a server system, said client system and said server system operative to exchange messages over a data network, said server system storing a program element for execution by a CPU, said program element comprising:

a. first program element component executed on said server system for receiving;

i. data conveying an image of the contents of a receptacle derived from an apparatus that scans the receptacle with penetrating radiation; and

ii. information from an automated threat detection processor indicating an area of interest in the image potentially containing a prohibited object;

b. a second program element component executed on said server system for processing the image to generate an enhanced image in which portions outside the area of interest are visually de-emphasized;

c. a third program element component executed on said server system for sending messages to said client system for causing said client system to display the enhanced image on a display device.

51. A client-server system as defined in claim 50, wherein the data network is the Internet.

52. An apparatus for implementing a user interface module for facilitating visual identification of a prohibited object in an image during security screening, said apparatus comprising:

a. means for receiving data conveying an image of the contents of a receptacle derived from an apparatus that scans the receptacle with penetrating radiation;

b. means for receiving information from an automated threat detection processor indicating an area of interest in the image potentially containing a prohibited object;

c. means for processing the image to generate an enhanced image in which portions outside the area of interest are visually de-emphasized;

d. means for releasing a display signal, the display signal being suitable for causing a display device to display the enhanced image.

53. A method for facilitating visual identification of a prohibited object in an image during security screening, said method comprising:

a. receiving data conveying an image of the contents of a receptacle derived from an apparatus that scans the receptacle with penetrating radiation;

b. receiving information from an automated threat detection processor indicating an area of interest in the image potentially containing a prohibited object;

c. processing the image to generate an enhanced image in which features appearing inside the area of interest are visually emphasized;

d. displaying the enhanced image on a display device.

54. A method as defined in claim 53, wherein processing the image includes increasing contrasts between features appearing in portions of the image inside the area of interest and background information appearing in portions of the image inside the area of interest.

55. A method as defined in claim 53, wherein processing the image includes modifying color information associated to features of the image appearing inside the area of interest.

56. A method as defined in claim 53, wherein said method comprises enlarging a portion of the image inside the area of interest such that at least some features of the enhanced image located inside the area of interest appear on a larger scale than features in portions of the enhanced image located outside the area of interest.

57. A method as defined in claim 53, said method comprising providing a user control allowing a user to select either one of the image conveyed by the data received and the enhanced image to be displayed on the display device.

58. A method as defined in claim 53, said method comprising:

a. providing a user control allowing a user to select a level of enhancement from a set of possible levels of enhancement;

b. processing the image to generate the enhanced image such that portions inside the area of interest in the enhanced image are visually emphasized at least in part based on the selected level of enhancement.

59. A method as defined in claim 53, said method comprising:

a. providing a user control allowing a user to select a level of enlargement from a set of possible levels of enlargement;

b. processing the image to generate the enhanced image such that portions inside the area of interest are enlarged at least in part based on the selected level of enlargement such that features of the portion of the enhanced image inside the area of interest appear on a larger scale than features in portions of the enhanced image outside the area of interest.

60. A method as defined in claim 59, wherein said user control allows the user to select the level of enlargement from the set of possible levels of enlargement by using an input device selected from the set consisting of a mouse, keyboard, pointing device, speech recognition unit and touch sensitive screen.

61. A method as defined in claim 53, wherein processing the image includes modifying portions of the image outside the area of interest.

62. A method as defined in claim 61, wherein processing the image includes attenuating portions of the image outside the area of interest.

63. An apparatus for implementing a user interface module for facilitating visual identification of a prohibited object in an image during security screening, said apparatus comprising:

a. a first input for receiving data conveying an image of the contents of a receptacle derived from an apparatus that scans the receptacle with penetrating radiation;

b. a second input for receiving information from an automated threat detection processor indicating an area of interest in the image potentially containing a prohibited object;

c. a processing unit in communication with the first input and the second input, said processing unit being operative for implementing the user interface module, said user interface module being adapted for;

i. processing the image to generate an enhanced image in which features appearing inside the area of interest are visually emphasized;

ii. displaying the enhanced image on a display module.

64. An apparatus as defined in claim 63, wherein processing the image includes increasing contrasts between features appearing in portions of the image inside the area of interest and background information appearing in portions of the image inside the area of interest.

65. An apparatus as defined in claim 63, wherein processing the image includes modifying color information associated to features of the image appearing inside the area of interest.

66. An apparatus as defined in claim 63, wherein processing the image includes enlarging a portion of the image inside the area of interest such that at least some features of the enhanced image located inside the area of interest appear on a larger scale than features in portions of the enhanced image located outside the area of interest.

67. An apparatus as defined in claim 63, said user interface module being adapted for displaying a user control allowing a user to select either one of the image conveyed by the data received and the enhanced image to be displayed on the display device.

68. An apparatus as defined in claim 63, said user interface module being adapted for:

a. displaying a user control allowing a user to select a level of enhancement from a set of possible levels of enhancement;

b. processing the image to generate the enhanced image such that portions inside the area of interest in the enhanced image are visually emphasized at least in part based on the selected level of enhancement.

69. An apparatus as defined in claim 63, wherein said user interface module being adapted for:

a. displaying a user control allowing a user to select a level of enlargement from a set of possible levels of enlargement;

b. processing the image to generate the enhanced image such that portions inside the area of interest are enlarged at least in part based on the selected level of enlargement such that features of the portion of the enhanced image inside the area of interest appear on a larger scale than features in portions of the enhanced image outside the area of interest.

70. An apparatus as defined in claim 69, wherein said user control allows the user to select the level of enlargement from the set of possible levels of enlargement by using an input device selected from the set consisting of a mouse, keyboard, pointing device, speech recognition unit and touch sensitive screen.

71. An apparatus as defined in claim 63, wherein processing the image includes modifying portions of the image outside the area of interest.

72. An apparatus as defined in claim 63, wherein processing the image includes attenuating portions of the image outside the area of interest.

73. A computer readable storage medium storing a program element suitable for execution by a CPU, said program element implementing a graphical user interface module for facilitating visual identification of a prohibited object in the image during security screening, said graphical user interface module being adapted for:

a. receiving data conveying an image of the contents of a receptacle derived from an apparatus that scans the receptacle with penetrating radiation;

b. receiving information from an automated threat detection processor indicating an area of interest in the image potentially containing a prohibited object;

c. processing the image to generate an enhanced image in which features appearing inside the area of interest are visually emphasized;

d. displaying the enhanced image on a display device.

74. A method for facilitating visual identification of prohibited objects in images associated with previously screened receptacles, said method comprising:

a. providing a plurality of records associated to respective previously screened receptacles, each record including;

i. an image of the contents of a receptacle derived from an apparatus that scans the receptacle with penetrating radiation;

ii. information derived from an automated threat detection processor and indicating an area of interest in the image potentially containing a prohibited object;

b. displaying on a displaying device a first viewing space conveying a set of thumbnail images, each thumbnail image in said set of thumbnail images being derived from a record in the plurality of records;

c. enabling a user to select at least one thumbnail image in the set of thumbnail images;

d. displaying on the display device a second viewing space conveying an enhanced image derived from a certain record in the plurality of records corresponding to the selected at least one thumbnail image.

75. A method as defined in claim 74, wherein said the user is enabled to select the at least one thumbnail image by using an input device selected from the set consisting of a mouse, keyboard, pointing device, speech recognition unit and touch sensitive screen.

76. A method as defined in claim 74, said method including displaying a user control for enabling the user to display different sets of thumbnail images in the first viewing space.

77. A method as defined in claim 74, wherein said user control is a scrolling control.

78. A method as defined in claim 74, wherein at least some records in said plurality of record include a level of risk data element conveying a perceived threat level associated to a respective previously screened receptacle.

79. A method as defined in claim 74, wherein at least some records in said plurality of record include a time stamp data element, wherein each thumbnail image in said set of thumbnail images conveys information derived from an associated time stamp data element.

80. A method as defined in claim 74, wherein said method comprises processing an image in the certain record at least in part based on information in the certain record indicating a certain area of interest to derive the enhanced image.

81. A method as defined in claim 80, wherein portions of the enhanced image inside the certain area of interest are visually emphasized.

82. A method as defined in claim 80, wherein portions of the enhanced image outside the certain area of interest are visually de-emphasized.

83. A method as defined in claim 74, wherein the enhanced image is an enhanced previous image, said method further comprising:

a. receiving data conveying a current image of the contents of a currently screened receptacle derived from an apparatus that scans the currently screened receptacle with penetrating radiation;

b. receiving information from an automated threat detection processor indicating an area of interest in the current image potentially containing a prohibited object;

c. processing the current image to generate an enhanced current image in which portions outside the area of interest are visually de-emphasized;

d. enabling the user to select between the enhanced previous image and the enhanced current image;

e. displaying the selected on of the enhanced current image and the enhanced previous image on a display module.

84. An apparatus for implementing a user interface module for facilitating visual identification of a prohibited object in an image during security screening, said apparatus comprising:

a. a memory suitable for storing a plurality of records associated to respective previously screened receptacles, each record including;

i. an image of the contents of a receptacle derived from an apparatus that scans the receptacle with penetrating radiation;

ii. information derived from an automated threat detection processor and indicating an area of interest in the image potentially containing a prohibited object;

b. a processing unit in communication with said memory unit, said processing unit implementing the user interface module, said user interface module being adapted for;

i. displaying on a displaying device a first viewing space conveying a set of thumbnail images, each thumbnail image in said set of thumbnail images being derived from a record in the plurality of records;

ii. enabling a user to select at least one thumbnail image in the set of thumbnail images;

iii. displaying on the display device a second viewing space conveying an enhanced image derived from a certain record in the plurality of records corresponding to the selected at least one thumbnail image.

85. An apparatus as defined in claim 84, wherein said user interface module enables the user to select the at least one thumbnail image by using an input device selected from the set consisting of a mouse, keyboard, pointing device, speech recognition unit and touch sensitive screen.

86. An apparatus as defined in claim 84, said user interface module is operative for displaying a user control for enabling the user to display different sets of thumbnail images in the first viewing space.

87. An apparatus as defined in claim 84, wherein said user control is a scrolling control.

88. An apparatus as defined in claim 84, wherein at least some records in said plurality of record include a level of risk data element conveying a perceived threat level associated to a respective previously screened receptacle, wherein each thumbnail image in said set of thumbnail images conveys information derived from an associated level of risk data element.

89. An apparatus as defined in claim 84, wherein at least some records in said plurality of record include a time stamp data element, wherein each thumbnail image in said set of thumbnail images conveys information derived from an associated time stamp data element.

90. An apparatus as defined in claim 84, wherein said user interface module is operative for processing an image in the certain record at least in part based on information in the certain record indicating a certain area of interest to derive the enhanced image.

91. An apparatus as defined in claim 90, wherein portions of the enhanced image inside the certain area of interest are visually emphasized.

92. An apparatus as defined in claim 90, wherein portions of the enhanced image outside the certain area of interest are visually de-emphasized.

93. An apparatus as defined in claim 84, wherein the enhanced image is an enhanced previous image, said user interface module being further operative for:

a. receiving data conveying a current image of the contents of a currently screened receptacle derived from an apparatus that scans the currently screened receptacle with penetrating radiation;

b. receiving information from an automated threat detection processor indicating an area of interest in the current image potentially containing a prohibited object;

c. processing the current image to generate an enhanced current image in which portions outside the area of interest are visually de-emphasized;

d. enabling the user to select between the enhanced previous image and the enhanced current image;

e. displaying the selected on of the enhanced current image and the enhanced previous image on a display module.

94. A computer readable storage medium storing a program element suitable for execution by a CPU, said program element implementing a graphical user interface module for facilitating visual identification of a prohibited object in the image during security screening, said graphical user interface module being adapted for:

a. providing a plurality of records associated to respective previously screened receptacles, each record including;

i. an image of the contents of a receptacle derived from an apparatus that scans the receptacle with penetrating radiation;

ii. information derived from an automated threat detection processor and indicating an area of interest in the image potentially containing a prohibited object;

b. displaying on a displaying device a first viewing space conveying a set of thumbnail images, each thumbnail image in said set of thumbnail images being derived from a record in the plurality of records;

c. enabling a user to select at least one thumbnail image in the set of thumbnail images;

d. displaying on the display device a second viewing space conveying an enhanced image derived from a certain record in the plurality of records corresponding to the selected at least one thumbnail image.

95. A method for displaying information associated to a receptacle for use in detecting the presence of a threat in the receptacle during security screening, said method comprising:

a. receiving data conveying an image of the contents of a receptacle derived from an apparatus that scans the receptacle with penetrating radiation;

b. receiving data conveying a level confidence that a threat has been detected in the receptacle;

c. deriving a perceived level of threat associated with the receptacle at least in part based on the level confidence;

d. displaying a screening image derived at least in part based on the data conveying the image of the contents of a receptacle;

e. displaying concurrently with the screening image a threat probability scale, the threat probability scale conveying a perceived level of threat associated with the receptacle in graphical format.