Rotation state estimation apparatus, method thereof, and program

A spin state estimation device comprising a processor executing a computer-executable instructions that cause the spin state estimation device to perform operations comprising:

• iteratively updating, based on varying w, an estimated spin state of a spinning object as output by comparing a target estimation image at a time point t+w·u and an object image at the time point t+w·u to dynamically select a combination of a hypothesis of spin state of a plurality of hypotheses of spin state and the w of a plurality of w,
• wherein an absolute value of the w is an integer of 1 or more,
• the u represents a unit time,
• the target estimation image at the time point t+w·u represents an image of the spinning object at the time point t+w·u estimated based on a captured image of the spinning object at a time point t from an input video in time-series according to the hypothesis of spin state of the plurality of hypotheses of spin state,
• the object image at the time point t+w·u represents another captured image of the spinning object obtained from the input video, and
• the dynamically selecting the combination of the hypothesis of spin state at the time point t+w·u and the w of the plurality of w is based on maximizing a likelihood of matching the target estimation image at the time point t+w·u and the object image at the time point t+w·u among target estimation images according to respective hypotheses of the plurality of hypotheses and respective w of the plurality of w, and the iteratively updating operation thereby enables estimating the spin state of the spinning object with accuracy over time.