Method and apparatus for assessing characteristics of liquids
A method to perform security screening at an airport on hand-carried baggage. The method includes requesting passengers with hand carried baggage to remove from the baggage a container that holds a liquid and perform an x-ray inspection on the hand carried baggage and on the container while the container remains outside the baggage. According to the method, the results of the x-ray inspection are used to determine if the baggage contains illegal objects and if the liquid is a security threat.
1. A system for determining a parameter of a liquid held in a container, said system comprising:
a) an input for receiving X-ray image data obtained by scanning the container holding the liquid with X-rays;
b) a computer based logic module for:
i) processing the X-ray image data to derive path length data, the path length data conveying an estimated length of a path followed by X-rays through the liquid held in the container;
ii) processing the X-ray image data in combination with the path length data to determine the parameter;
c) an output to release data conveying the parameter.
2. A system as defined in claim 1 , wherein the parameter is selected from the group consisting of a density, an X-ray attenuation coefficient and an effective atomic number.
3. A system as defined in claim 1 , wherein the system comprises an X-ray imaging apparatus including a conveyor belt on which the container holding the liquid to be scanned is placed and which transports the container holding the liquid through the X-ray imaging apparatus, said X-ray imaging apparatus generating said X-ray image data by scanning the container holding the liquid transported on the conveyor belt.
4. A system as defined in claim 3 , wherein the X-ray imaging apparatus that scans the container holding the liquid is a dual energy X-ray imaging apparatus.
5. A system as defined in claim 3 , wherein the container holding the liquid is scanned in a tray that is carried on the conveyor belt.
6. A system as defined in claim 1 , wherein the computer based logic module processes the X-ray image data to extract X-ray attenuation information and processes the X-ray attenuation information and the path length data to derive the parameter.
7. A system as defined in claim 6 , wherein the X-ray attenuation information includes X-ray attenuation information associated with a first X-ray energy level and X-ray attenuation information associated with a second X-ray energy level, where the first energy level is higher than the second energy level.
8. A system as defined in claim 5 , wherein the image data conveys a two dimensional image of the container.
9. A system as defined in claim 1 , wherein the computer based logic module processes the X-ray image data to extract X-ray attenuation information indicative of a degree of attenuation of X-rays by the liquid held in the container and processes the X-ray attenuation data and the path length data to derive the parameter.
10. A method for determining a parameter of a liquid held in a container, said method comprising:
a) receiving X-ray image data of the container holding the liquid, the X-ray image data being obtained by scanning the container holding the liquid with X-rays;
b) processing the X-ray image data with a computer to:
i) derive path length data at least in part based on the X-ray image data, the path length data conveying an estimated length of a path followed by X-rays through the liquid held in the container;
ii) processing the X-ray image data in combination with the path length data to determine the parameter;
c) releasing data conveying the parameter.
11. A method as defined in claim 10 , wherein the parameter is selected from the group consisting of a density, an X-ray attenuation coefficient and an effective atomic number.
12. A method as defined in claim 10 , wherein said X-ray image data is obtained by scanning the container holding the liquid while the container is transported on a conveyor belt of an X-ray imaging apparatus.
13. A method as defined in claim 12 , wherein the container holding the liquid is scanned in a tray that is carried on the conveyor belt.
14. A method as defined in claim 10 , wherein said X-ray image data is obtained by scanning the container holding the liquid with dual energy X-rays.
15. A method as defined in claim 10 , including processing the X-ray image data to extract X-ray attenuation information and processing the X-ray attenuation information and the path length data to derive the parameter.
16. A method as defined in claim 15 , wherein the X-ray attenuation information includes X-ray attenuation information associated with a first X-ray energy level and X-ray attenuation information associated with a second X-ray energy level, where the first energy level is higher than the second energy level.
17. A method as defined in claim 10 , including processing the X-ray image data to extract X-ray attenuation information indicative of a degree of attenuation of X-rays by the liquid held in the container and processing the X-ray attenuation data and the path length data to derive the parameter.
18. A computer readable storage medium for storing a program element suitable for execution by a computing apparatus, said computing apparatus comprising a memory unit and a processor operatively connected to said memory unit, said program element when executing on said processor implementing a method for determining a parameter of a liquid held in a container comprising:
a) receiving X-ray image data of the container holding the liquid, the X-ray image data being obtained by scanning the container holding the liquid with X-rays;
b) processing the X-ray image data with a computer to:
i) derive path length data at least in part based on the X-ray image data, the path length data conveying an estimated length of a path followed by X-rays through the liquid held in the container;
ii) processing the X-ray image data in combination with the path length data to determine the parameter;
c) releasing data conveying the parameter.
19. A system for determining a parameter of a liquid held in a container, said system comprising:
a) an input for receiving X-ray image data obtained by scanning the container holding the liquid with X-rays;
b) a computer based logic module for:
i) processing the X-ray image data to:
(1) derive X-ray attenuation data indicative of a degree at which X-rays are attenuated by the liquid held in the container;
(2) derive path length data, the path length data conveying an estimated length of a path followed by X-rays through the liquid held in the container;
ii) deriving the parameter at least in part on the basis of the X-ray attenuation data and the path length data;
c) an output to release data conveying the parameter.
20. A system as defined in claim 19 , wherein the parameter is selected from the group consisting of a density, an X-ray attenuation coefficient and an effective atomic number.
21. A system as defined in claim 19 , wherein the system comprises an X-ray imaging apparatus including a conveyor belt on which the container holding a liquid to be scanned is placed and which transports the container holding the liquid through the X-ray imaging apparatus, said X-ray imaging apparatus generating said X-ray image data by scanning the container holding the liquid transported on the conveyor belt.
22. A system as defined in claim 21 , wherein the X-ray imaging apparatus that scans the container holding the liquid is a dual energy X-ray imaging apparatus.
23. A system as defined in claim 21 , wherein the container holding the liquid is scanned in a tray that is carried on the conveyor belt.
24. A system as defined in claim 19 , wherein the X-ray attenuation data conveys X-ray attenuation information associated with a first X-ray energy level and X-ray attenuation information associated with a second X-ray energy level, where the first energy level is higher than the second energy level.
25. A system as defined in claim 19 , wherein the X-ray image data conveys a two dimensional image of the container.
26. A method for determining a parameter of a liquid held in a container, said method comprising:
a) receiving X-ray image data of the container holding the liquid, the X-ray image data being obtained by scanning the container holding the liquid with X-rays;
b) processing the X-ray image data with a computer to:
i) derive X-ray attenuation data, the X-ray attenuation data being indicative of a degree at which X-rays are attenuated by the liquid held in the container;
ii) derive path length data, the path length data conveying an estimated length of a path followed by X-rays through the liquid held in the container;
c) process the X-ray attenuation data and the path length data with the computer to derive the parameter;
d) releasing data conveying the parameter from an output of the computer.
27. A method as defined in claim 26 , wherein the parameter is selected from the group consisting of a density, an X-ray attenuation coefficient and an effective atomic number.
28. A method as defined in claim 26 , wherein said X-ray image data is obtained by scanning the container holding the liquid while the container is transported on a conveyor belt of an X-ray imaging apparatus.
29. A method as defined in claim 28 , wherein the container holding the liquid is scanned in a tray that is carried on the conveyor belt.
30. A method as defined in claim 26 , wherein said X-ray image data is obtained by scanning the container holding the liquid with dual energy X-rays.
31. A method as defined in claim 26 , wherein the X-ray attenuation data conveys X-ray attenuation information associated with a first X-ray energy level and X-ray attenuation information associated with a second X-ray energy level, where the first energy level is higher than the second energy level.
32. A method as defined in claim 26 , wherein the X-ray image data conveys a two dimensional image of the container.