Virtual Camera Friendly Optical Tracking

Patent metadata

Field	Value
Publication number	US-2023162378-A1
Application number	US-202017915048-A
Country	US
Kind code	A1
Filing date	May 21, 2020
Priority date	May 21, 2020
Publication date	May 25, 2023
Grant date	—

Abstract

A method for player and ball tracking post processing is described herein. The method includes optically tracking a trajectory of a player and ball and determining at least one affinity player for the currently tracked player. Additionally, the method includes completing the optical trajectory for the currently tracked player based on an estimated trajectory from the affinity player and stabilizing ball tracking during game break. The method further includes calculating virtual camera movement.

First claim

1 . A method for player and ball tracking post processing, the method comprising:
optically tracking a trajectory of a player and a ball; determining at least one affinity player for the currently tracked player; completing the optical trajectory for the currently tracked player based on an estimated trajectory from the affinity player; stabilizing ball tracking during game break; and calculating virtual camera movement.

2 . The method of claim 1 , wherein the affinity player is from the opposing team.

3 . The method of claim 1 , further including selecting a plurality of affinity players, wherein a mean location of the affinity players is used to derive the location of the current player.

4 . The method of claim 1 , wherein the affinity player location is used to determine the missing trajectory of the current player until the current player is recovered in normal optical tracking.

5 . The method of claim 1 , wherein refining the trajectory includes using a quadratic Bezier curve to smooth the trajectory.

6 . The method of claim 1 , wherein stabilizing the ball tracking includes determining a game break and stabilizing the ball trajectory during the game break.

7 . The method of claim 1 , wherein stabilizing the ball tracking includes fixing the virtual camera to reset for a new play.

8 . The method of claim 1 , wherein the virtual camera focus area is calculated by determining a 3D region of interest such that the temporal association is found by determining a bounding box including the first player in multiple frames of a same camera view of the captured field of view.

9 . The method of claim 1 , further including:
constructing a virtual camera within a three-dimensional volumetric representation of the captured field of view, and progressing through the three-dimensional volumetric representation according to the generated trajectory.

10 . A system for trajectory generation based on player tracking, the system comprising:
an optical trajectory receiver to receive an optical trajectory of a player and a ball; an affinity tracker to determine at least one affinity player for the currently tracked player; a trajectory refiner to complete the optical trajectory for the currently tracked player based on an estimated trajectory from the affinity player; a trajectory stabilizer to stabilize ball tracking during game break; and a virtual camera calculator to calculate virtual camera movement.

11 . The system of claim 10 , wherein the affinity player is from the opposing team.

12 . The system of claim 10 , wherein a plurality of affinity players is selected, and wherein a mean location of the affinity players is used to derive the location of the current player.

13 . The system of claim 10 , wherein the affinity player location is used to determine the missing trajectory of the current player until the current player is recovered in normal optical tracking.

14 . The system of claim 10 , wherein refining the trajectory includes using a quadratic Bezier curve to smooth the trajectory.

15 . The system of claim 10 , wherein the ball tracking is stabilized by determining a game break and stabilizing the ball trajectory during the game break.

16 . The system of claim 10 , wherein the ball tracking is stabilized by the virtual camera being fixed to reset for a new play.

17 . The system of claim 10 , wherein the virtual camera focus area is calculated by determining a 3D region of interest such that the temporal association is found by determining a bounding box including the first player in multiple frames of a same camera view of the captured field of view.

18 . The system of claim 10 , wherein a virtual camera is stabilized within a three-dimensional volumetric representation of the captured field of view, and wherein the virtual camera is moved through the three-dimensional volumetric representation according to the generated trajectory.

19 . At least one non-transitory computer-readable medium comprising instructions, which when executed, cause a processor to:
optically track a trajectory of a player and a ball; determine at least one affinity player for the currently tracked player; complete the optical trajectory for the currently tracked player based on an estimated trajectory from the affinity player; stabilize ball tracking during game break; and calculate virtual camera movement.

20 . The computer readable medium of claim 19 , wherein the affinity player is from the opposing team.

21 . The computer readable medium of claim 19 , wherein the instructions cause the processor to select a plurality of affinity players, wherein a mean location of the affinity players is used to derive the location of the current player.

22 . The computer readable medium of claim 19 , wherein the affinity player location is used to determine the missing trajectory of the current player until the current player is recovered in normal optical tracking.

23 . The computer readable medium of claim 19 , wherein the trajectory is refined using a quadratic Bezier curve to smooth the trajectory.

24 . The computer readable medium of claim 19 , wherein the ball tracking is stabilized by determining a game break and stabilizing the ball trajectory during the game break.

25 . The computer readable medium of claim 19 , wherein the ball tracking is stabilized by fixing the virtual camera to reset for a new play.

Assignees

• Intel Corp

Inventors

• Ling Chen
• Li Wenlong
• Li Qiang
• Lin Haihua
• Tong Xiaofeng

Classifications

• G06T7/292 Primary

  Multi-camera tracking · CPC title

• G06V20/42

  of sport video content · CPC title

• G06T2207/30224

  Ball; Puck · CPC title

• G06V10/62 Primary

  relating to a temporal dimension, e.g. time-based feature extraction; Pattern tracking · CPC title

• G06T2207/30241

  Trajectory · CPC title