Patent ID: 6775405
Filing Date: 2004-08-10
Classification: G06K,G06T

Abstract:
A method for registering a first volumetric image and a second volumetric image, each image comprising a three-dimensional array of gray scale voxel values, and each image having a marginal probability density function (pdf) of voxel values, the method comprising:(a) determining one or more prior joint voxel value probability density functions for the first and second images to provide a corresponding one or more prior pdf estimates including at least one prior unlikely pdf estimate selected from a group consisting of: a uniform distribution, and an unlikely pdf estimate that is proportional to the marginal pdf of one of the first and second images; (b) selecting a first transform defining a geometric relationship of the second image relative to the first image; (c) calculating a measure of the cross-entropy for the geometric relationship using the one or more prior pdf estimates; (d) selecting a different transform defining a geometric relationship of the second image relative to the first image; and (e) iteratively repeating steps (c) and (d) until an optimal transform is calculated, the optimal transform corresponding to a geometric relationship providing an optimized measure of the cross-entropy.