Patent ID: 11908214
Assignee: NEC CORPORATION
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 1:
2. The object management system according to claim 1, further comprising
a third memory that calculates, for each of a plurality of reference images in which a reference circle is captured from various capturing directions, a feature amount of a reference ellipse corresponding to the reference circle in the reference image, and a distance between a center point of the reference ellipse and a point in the reference image corresponding to a center of the reference circle, and stores the feature amount of the reference ellipse and the distance in association with each other in advance, wherein
the processor is further configured to execute the instructions to
acquire, from the third memory, the distance corresponding to the feature amount of the reference ellipse that matches a feature amount of the first ellipse, and calculate a projective transformation coefficient for projective transformation by using coordinate values of a square before and after the projective transformation, the square having vertexes that are four points in total including two intersection points between a straight line and the first ellipse, the straight line running through a point away from a center of the first ellipse by the distance in a depth direction of a short axis of the first ellipse in parallel with a long axis of the first ellipse, and both end points of the short axis of the first ellipse.