Claims
- 1. A method for non-rigid image registration using distance functions, the method comprising:
receiving a plurality of pixels defining a source shape and a target shape into an n-dimensional image space; and computing a distance map responsive to the shape by calculating a minimum distance from each point in the image space to a closest portion of the shape and defining a higher-dimensional n+1 information space for shape registration.
- 2. A method as defined in claim 1, further comprising:
cloning the shape within the image space; and computing a distance map responsive to the cloned shape by calculating a minimum distance from each point in the image space to a closest portion of the cloned shape.
- 3. A method as defined in claim 2, further comprising performing a global registration that is invariant to rotation, translation and scale, by minimizing an energy cost function in the information space.
- 4. A method as defined in claim 3 wherein the energy function is optimized to recover global registration parameters for the source shape.
- 5. A method as defined in claim 3, further comprising minimizing the energy cost function using a gradient-descent method.
- 6. A method as defined in claim 5, further comprising estimating local deformations from the global registration to optimize the fit of a source shape to the target shape.
- 7. A method as defined in claim 3 wherein the energy function is responsive to local deformations.
- 8. A method as defined in claim 7 wherein the global transformation and the local deformations are combined using a local deformation file.
- 9. A method as defined in claim 8 wherein the local deformation file meets a regular and smooth regularity constraint.
- 10. A method as defined in claim 9, further comprising minimizing the energy cost function using a gradient-descent method.
- 11. A method as defined in claim 5, further comprising registering the source shape to a shape model.
- 12. A method as defined in 11 wherein a global-to-local registration is optimized in accordance with the local quality of the model.
- 13. A method as defined in claim 12, further comprising minimizing a stochastic cost function in accordance with the quality of the model.
- 14. A method as defined in claim 13, further comprising minimizing the energy cost function using a gradient-descent method.
- 15. A method for non-rigid image registration using distance functions, the method comprising:
receiving a source shape and a target shape; creating an augmented registration space comprising a plurality of target shape clones coherently positioned in an information space; integrating at least one global linear registration model with local deformations to assess the source shape; optimizing a functional defined on a parameter or feature space, the functional quantifying the similarity between the source shape and at least one target shape in terms of distance functions; and registering the source shape by seeking mutual correspondences between the source shape, the target shape and the target shape clones.
- 16. A method as defined in claim 15 wherein optimizing comprises selecting a mathematical framework by finding an optimum of at least one functional to quantify the similarity between the source shape and at least one target shape.
- 17. A method as defined in claim 16 wherein the mathematical framework is defined by at least one of variational and stochastic principles.
- 18. A method as defined in claim 15 wherein optimizing comprises the use of a gradient-descent method within the mathematical framework.
- 19. A method as defined in claim 15 wherein the image space is greater than a two-dimensional image plane.
- 20. A method as defined in claim 15 wherein the source shape comprises uncertainties, the method further comprising:
considering a linear parametric model and a pixel-wise deformation field resulting in a non-rigid registration paradigm; and recovering both of the linear parametric model and a pixel-wise deformation field simultaneously through a gradient-descent method.
- 21. An apparatus for non-rigid image registration using distance functions, the apparatus comprising:
a receiving unit for receiving a source shape and a target shape; a cloning unit in signal communication with the optimizing unit for creating an augmented registration space comprising a plurality of target shape clones coherently positioned in the information space; an integrating unit in signal communication with the receiving unit for integrating at least one global linear registration model with local deformations to assess the source shape; an optimizing unit in signal communication with the integrating unit for optimizing a functional defined on a parameter or feature space, the functional quantifying the similarity between the source shape and at least one target shape in terms of distance functions; and a registration unit in signal communication with the tracking unit for registering the source shape by seeking mutual correspondences between the source shape, the target shape and the target shape clones.
- 22. A system for non-rigid image registration using distance functions, the system comprising:
receiving means for receiving a source shape and a target shape; cloning means in signal communication with the optimizing means for creating an augmented registration space comprising a plurality of target shape clones coherently positioned in the information space; integrating means in signal communication with the receiving means for integrating at least one global linear registration model with local deformations to assess the source shape; optimizing means in signal communication with the integrating means for optimizing a functional defined on a parameter or feature space, the functional quantifying the similarity between the source shape and at least one target shape in terms of distance functions; and registration means in signal communication with the tracking means for registering the source shape by seeking mutual correspondences between the source shape, the target shape and the target shape clones.
- 23. A program storage device readable by machine, tangibly embodying a program of instructions executable by the machine to perform program steps for non-rigid image registration using distance functions, the program steps comprising:
receiving a source shape and a target shape; creating an augmented registration space comprising a plurality of target shape clones coherently positioned in the information space; integrating at least one global linear registration model with local deformations to assess the source shape; optimizing a functional defined on a parameter or feature space, the functional quantifying the similarity between the source shape and at least one target shape in terms of distance functions; and registering the source shape by seeking mutual correspondences between the source shape, the target shape and the target shape clones.
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application Serial No. 60/353,371 (Attorney Docket No. 2002P01 771 US), filed Feb. 1, 2002 and entitled “Matching Distance Functions: A Shape-to-Area Variational Approach for Global-to-Local Registration”, which is incorporated herein by reference in its entirety.
Provisional Applications (1)
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Number |
Date |
Country |
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60353371 |
Feb 2002 |
US |