Abstract: Automatic club recognition during a golf swing is provided. At least one processor receives a series of images of a golf club captured during a golf swing. At least one processor detects from the series of images one or more sticker labels placed on the golf club. At least one processor classifies a golf club type of the golf club based on recognizing a marker, e.g., a unique or particular marker, coded on the one or more sticker labels, the marker for representing a specific type of golf club.

Abstract: A calibration mark apparatus includes a support having at least one wall with at least one calibration pattern on the least one wall and at least one attachment portion extending from the least one wall. The attachment portion may be a flap extending from at least one wall for attaching the support to a surface or a net. The support may be a three-dimensional (3D) structure. The calibration mark apparatus may have walls that are foldable along a common edge into a single plane. The calibration mark apparatus may have a base connecting the walls including raised tab portions arranged to fit into slots in the flap. The flap may include openings for attaching multiple supports together by a rope that is arranged to feed through the openings. The calibration mark apparatus may include a bracket to mount the support to a surface or a net by clips.