Image processing method for motion estimation in a sequence of images, method of filtering noise, and medical imaging apparatus utilising these methods

摘要

The image processing method includes a stage for determination of a field of movement vectors of a temporal image on the basis of an algorithm for placing into correspondence image blocks. The method includes the following stages: - acquisition of a sequence of three successive temporal images, including an image to be processed (Jt) between an earlier 'causal' image (Jt-1) and a later 'anti-causal' image (Jt+1); - determination of a reference block (RBt) in the image to be processed and for a couple of blocks respectively localized in the causal and anti-causal images (CBt-1,CBt+1), the best corresponding to the reference block (RBt) according to a similar intensity criteria, and; - determination of a movement vector relative to the reference block on the basis of the localization of the blocks of this pair with respect to the localization of the reference block. The intensity similarity criteria is based on a linear, uniform, continuos movement hypothesis of the corresponding block in the causal image to the corresponding block in the anti-causal image, so as to select blocks corresponding symmetrically in relation to the reference block and to determine the symmetric movement vectors of the reference block towards each of the correspondent blocks. The system also includes a recursive time noise filter for an image sequence with movement compensation based on the vectors and an X ray device including the system.