Patent attributes
Methods and devices for tracking an x-ray tube focal spot position are described. As successive images are captured by an image capturing system that includes the x-ray tube, the focal spot may change position. To track the change, one or more artificial targets may be arranged relative to the image capturing system such that an initial image is received that includes the artificial targets at a first position in the initial image. A gain map may be generated based on the initial image, and applied to a subsequent image received that also includes the artificial targets to generate a normalized subsequent image. A shift of the artificial targets from the first position in the initial image to a second position in the normalized subsequent image may be identified, where the shift corresponds to the focal spot's position change. Mathematical and/or physical adjustments may be made to correct for the change.