Experiencing the ball's POV for ballistic sports

ABSTRACT

We place a small wireless camera inside an American football to capture the ball's point-of-view during flight to augment a spectator's experience of the game of football. To this end, we propose a robust video synthesis algorithm that leverages the unique constraints of fast spinning cameras to obtain a stabilized bird's eye point-of-view video clip. Our algorithm uses a coarse-to-fine image homography computation technique to progressively register images. We then optimize an energy function defined over pixel-wise color similarity and distance to image borders, to find optimal image seams to create panoramic composite images. Our results show that we can generate realistic videos from a camera spinning at speeds of up to 600 RPM.

References

1. Camera inside a football films view from air. Popular Mechanics, December 1938.
2. Y. Boykov and V. Kolmogorov. An experimental comparison of min-cut/max-flow algorithms for energy minimization in vision. Transactions on Pattern Analysis and Machine Intelligence, 26(9):1124 1137, 2004.
3. M. Brown and D. Lowe. Automatic panoramic image stitching using invariant features. International Journal of Computer Vision, 74(1):59 73, 2007.
4. R. Hartley and A. Zisserman. Multiple View Geometry in Computer Vision. Cambridge University Press, second edition, 2004.
5. J. Hedborg, E. Ringaby, P.-E. Forssén, and M. Felsberg. Structure and motion estimation from rolling shutter video. In Computer Vision Workshops (ICCV Workshops), 2011 IEEE International Conference on, pages 17 23, 2011.
6. K. Kitani, K. Horita, and H. Koike. Ballcam!: dynamic view synthesis from spinning cameras. In Adjunct proceedings of the 25th annual ACM symposium on User interface software and technology, pages 87 88, 2012.
7. T. Kuwa, Y. Watanabe, T. Komuro, and M. Ishikawa. Wide range image sensing using a thrown-up camera. In Multimedia and Expo (ICME), 2010 IEEE International Conference on, pages 878 883, 2010.
8. D. Lowe. Object recognition from local scale-invariant features. In International Conference on Computer Vision, volume 2, pages 1150 1157, 1999.
9. H. Mori, D. Sekiguchi, S. Kuwashima, M. Inami, and F. Matsuno. Motionsphere. In ACM SIGGRAPH 2005 Emerging technologies, page 15, 2005.
10. T. Ozawa, K. M. Kitani, and H. Koike. Human-centric panoramic imaging stitching. In Proceedings of the 3rd Augmented Human International Conference, page 20, 2012.
11. J. Pfeil, K. Hildebrand, C. Gremzow, B. Bickel, and M. Alexa. Throwable panoramic ball camera. In SIGGRAPH Asia 2011 Emerging Technologies, page 4, 2011.

Index Terms

• Computing methodologies

  • Computer graphics

    • Graphics systems and interfaces

      • Virtual reality

• Human-centered computing

  • Human computer interaction (HCI)

    • Interaction paradigms

      • Mixed / augmented reality

      • Virtual reality