Definitions for "Image registration"
Alignment process by which two images of the same scene are positioned coincident with respect to each other so that corresponding elements of the same ground appear in the same position on the registered images.
Volumetric (manual) image registration procedures are described ([] Evans et al., 1991a). In the context of Pet/mri data analysis, the MRI volume from each subject is aligned with the corresponding PET volume. An orthogonal coordinate frame is then established based on the anterior commissure - posterior commissural (AC-PC) line as identified in the MRI volume ([] Evans et al., 1992). These anatomical frame coordinates are then used to apply a trilinear re-sampling of each matched pair of MRI and PET datasets into a standardized stereotactic coordinate system ([] Fox et al., 1985; [ 13] Talairach et al., 1988). A fully automatic method, based on multi-scale, three dimensional (3D) cross-correlation between features (image intensity and 3D gradient magnitude) of the volume to register and a target model volume (already in the target space) has also been developed in []. When this method fails, we resort to the manual method described previously.
The use of an image on a document (such as a square or a triangle), both contiguous and containable, as a registration point to help OCR for AnyDoc auto ID a document type.