CT scanner calibration
A system and method can determine one or more CT scanner calibration parameters from a plurality of calibration object projections in a plurality of radiographs.
1. A method of determining CT calibration settings, the method comprising:
receiving a plurality of radiographs from a CT scanner, each of the plurality of radiographs comprising a plurality of calibration object projections; and
determining one or more CT scanner calibration parameters from a plurality of calibration object projections in the plurality of radiographs prior to CT reconstruction.
2. The method of claim 1 , wherein the calibration object projections are projections of spherical calibration objects arranged in a calibration object holder.
3. The method of claim 1 , wherein the CT scanner is a cone beam scanner.
4. The method of claim 1 , wherein the one or more CT scanner calibration parameters comprise one or more from the group consisting of a projected horizontal axis shift, a projected rotational axis inclination angle, a vertical shift, detector distance, and axis of rotation distance.
5. The method of claim 1 , wherein determining one or more CT scanner calibration parameters comprises determining a first projection position of each of the plurality of calibration objects in a first projection of the plurality of radiographs.
6. The method of claim 5 , wherein determining the first projection position comprises determining a histogram of pixel values in the first projection.
7. The method of claim 1 , further comprising tracking the plurality of calibration objects in the plurality of radiographs.
8. The method of claim 1 , further comprising determining a rotation direction from the plurality of radiographs.
9. The method of claim 1 , further comprising pre-processing the plurality of radiographs.
10. A system for determining CT calibration settings, comprising:
a processor; and
a non-transitory computer-readable storage medium comprising instructions executable by the processor to perform steps comprising:
receiving a plurality of radiographs from a CT scanner, each of the plurality of radiographs comprising a plurality of calibration object projections; and
determining one or more CT scanner calibration parameters from a plurality of calibration object projections in the plurality of radiographs prior to CT reconstruction.
11. The system of claim 10 , wherein the calibration object projections are projections of spherical calibration objects arranged in a calibration object holder.
12. The system of claim 11 , further comprising tracking the plurality of calibration objects in the plurality of radiographs.
13. The system of claim 10 , wherein the CT scanner is a cone beam scanner.
14. The system of claim 10 , wherein the one or more CT scanner calibration parameters from the projective transformation comprise one or more from the group consisting of a projected horizontal axis shift, a projected rotational axis inclination angle, a vertical shift, detector distance, and axis of rotation distance.
15. The system of claim 10 , wherein determining one or more CT scanner calibration parameters comprises determining a first projection position of each of the plurality of calibration objects in a first projection of the plurality of radiographs.
16. The system of claim 15 , wherein determining the first projection position comprises determining a histogram of pixel values in the first projection.
17. The system of claim 10 , further comprising tracking the plurality of calibration objects in the plurality of radiographs.
18. The system of claim 10 , further comprising determining a rotation direction from the plurality of radiographs.
19. The system of claim 10 , further comprising pre-processing the plurality of radiographs.
20. A non-transitory computer readable medium storing executable computer program instructions to determine CT calibration settings, the computer program instructions comprising instructions for:
receiving a plurality of radiographs from a CT scanner, each of the plurality of radiographs comprising a plurality of calibration object projections; and
determining one or more CT scanner calibration parameters from a plurality of calibration object projections in the plurality of radiographs prior to CT reconstruction.