Patent ID: 9367917
Filing Date: 2016-06-14
CPC Classification: G06T

Claim Text:
1. A treatment planning apparatus comprising: at least one processor arranged to iteratively determine a co-registration transformation between a first image and a second image on the basis of a set of initial parameters which includes selecting a random distribution of sample pixels in one image to use for the determination; wherein the apparatus is arranged to: employ the at least one processor to determine a first co-registration transformation between the first image and the second image on the basis of a first set of initial parameters; employ the at least one processor to determine a plurality of additional co-registration transformations, each additional determination having an iterative starting point based on the first co-registration transformation, and using a set of initial parameters that differ from the first set of initial parameters; and measure the variation in at least the additional co-registration transformations so as to estimate an error in the first co-registration transformation, in which the set of initial parameters for at least one of the additional co-registration transformations differs from the first set of initial parameters at least in respect of: a candidate transformation which the iteration uses as its starting point; by a selection of the random distribution of sample pixels, and by using only a sub-region of at least one of the first image and the second image.