1. A system for generating calibration information usable for wafer inspection, the system comprising: a displacement analysis module, configured to: (a) calculate a displacement for each target out of multiple targets selected in multiple scanned frames which are included in a scanned area of the wafer, the calculating based on a correlation of: (i) an image associated with the respective target which was obtained during a scanning of the wafer, and (ii) design data corresponding to the image; and (b) determining a displacement for each of the multiple scanned frames, the determining based on the displacements calculated for multiple targets in the respective scanned frame; and a subsequent processing module, configured to generate: (a) calibration information including the displacements determined for the multiple scanned frames, and (b) a target database that includes target image and location information of each target of a group of database targets, the group including multiple targets in each of the multiple scanned frames.