| [ Previous | [ 1] | [ 2] | [ 3] | [ 4] | [ 5] | [ 6] | [ 7] | [ 8] | [ 9] | [ 10] | [ 11] | [ 12] | [ 13] | [ 14] | [ 15] | [ 16] | [ 17] | [ 18] | [ 19] | [ 20] |
¡@
Hua-Tsung Chen, Hsuan-Sheng Chen, Ming-Ho Hsiao, Wen-Jiin Tsai and Suh-Yin Lee
Department of Computer Science and Information Engineering
National Chiao Tung University
Hsinchu, 300 Taiwan
Pitching contents play the key role in the resultant victory or defeat in a baseball
game. Utilizing the physical characteristic of ball motion, this paper presents a trajectory-
based framework for automatic ball tracking and pitching evaluation in broadcast
baseball videos. The task of ball detection and tracking in broadcast baseball videos is
very challenging because in video frames, the noises may cause many ball-like objects,
the ball size is small, and the ball may deform due to its high speed movement. To overcome
these challenges, we first define a set of filters to prune most non-ball objects but
retain the ball, even if it is deformed. In ball position prediction and trajectory extraction,
we analyze the 2D distribution of ball candidates and exploit the characteristic that the
ball trajectory presents in a near parabolic curve in video frames. Most of the non-qualified
trajectories are pruned, which greatly improves the computational efficiency. The
missed balls can also be recovered in the trajectory by applying the position prediction.
The experiments of ball tracking on the testing sequences of JPB, MLB and CPBL captured
from different TV channels show promising results. The ball tracking framework is
able to extract the ball trajectory, superimposed on the video, and in near real-time provide
visual enrichment before the next pitch coming up without specific cameras or
equipments set up in the stadiums. It can also be utilized in strategy analysis and intelligence
statistics for player training.
Received February 2, 2007; accepted July 13, 2007.
Communicated by K. Robert Lai, Yu-Chee Tseng and Shu-Yuan Chen.
*The research is partially supported by the National Science Council of Taiwan, R.O.C., under the grant No.
NSC 95-2221-E-009-076-MY3 and partially supported by Lee and MTI center for Networking Research at
National Chiao Tung University.