TRUE SPACE TRACKING OF AXISYMMETRIC OBJECT FLIGHT USING DIAMETER MEASUREMENT

摘要

Methods and apparatus for determining a trajectory of a axisymmetric object in 3-D physical space using a digital camera which records 2-D image data are described. In particular, based upon i) a characteristic length of the axisymmetric object, ii) a physical position of the camera determined from sensors associated with the camera (e.g., accelerometers) and iii) captured 2-D digital images from the camera including a time at which each image is generated relative to one another, a position, a velocity vector and an acceleration vector can be determined in three dimensional physical space for axisymmetric object objects as a function of time. In one embodiment, the method and apparatus can be applied to determine the trajectories of objects in games which utilize axisymmetric object objects, such as basketball, baseball, bowling, golf, soccer, rugby or football.

主权项

1. A non-transitory computer readable medium for storing a computer program used by a computing device, the computer program executed by the computing device to generate a three dimensional (3-D) trajectory of an axisymmetric object from two dimensional (2-D) digital image data, the computer readable medium comprising:
computer code for receiving a sequence of 2-D digital images from a digital camera associated with the computing device; computer code for receiving orientation data which is used to determine or to specify an orientation of a lens of the digital camera in 3-D physical space, said lens configured to receive light used to generate the 2-D digital images; computer code for transforming pixel data in each of the 2-D digital images based upon the determined orientation of the lens; computer code for identifying a 2-D representation of an axisymmetric object captured in the transformed pixel data associated with each of the 2-D digital images; computer code for determining pixel coordinates of the 2-D representation of the axisymmetric object in each of the 2-D digital images; computer code for determining a characteristic length of the 2-D representation of the axisymmetric object measured in pixels in each of the 2-D digital images wherein the characteristic length of the 2-D representation varies within the sequence of the 2-D digital images; computer code for determining a distance to the identified 2-D representation of the axisymmetric object from the lens based upon the characteristic length in the pixels, said distance measured in units associated with 3-D physical space; and computer code for determining 3-D coordinates of the axisymmetric object as a function of time in the 3-D physical space based upon the determined distance and the pixel coordinates of the 2-D representation of the axisymmetric object captured in the transformed pixel data associated with each of the 2-D digital images.