Position analysis device and method, and camera system

A position analysis device for measuring a target position in a subject based on a captured image of the subject by a camera, the position analysis device comprising:

• an input interface that acquires the captured image obtained by the camera;
• a processor that calculates coordinate transformation from a first coordinate system to a second coordinate system with respect to the target position in the acquired captured image, the first coordinate system providing measure in the captured image, the second coordinate system providing measure in the subject;
• and
• a memory that stores a correction model to generate a correction amount of a position in the second coordinate system, wherein
• the processor corrects a transformed position from the target position, based on the correction model including a plurality of weight functions corresponding to a plurality of reference positions, the transformed position being a position obtained by the coordinate transformation on the target position in the first coordinate system to the second coordinate system, the weight functions each producing a larger weighting in the correction amount as the transformed position is closer to a corresponding reference position, the reference positions being different from each other in the second coordinate system.