Academia.eduAcademia.edu

Outline

MPEG-2 Motion Estimation using a PC Cluster

International Journal of Computers and Applications

Abstract

Motion estimation is the most computing-intensive component of the MPEG-2 encoding process. It refers to the action of searching for the closest prediction of a certain image block. The more accurate the prediction, the better the achieved compression and quality are. The optimal solution is guaranteed by performing an exhaustive search for all possible predictions for a certain block. The motion estimation component is characterized by a polynomial time, and is responsible for about 90% of the encoding time. In this article the search time is reduced by parallelizing the block matching search algorithm, used in addition to the partial distance method to prevent useless but time-expensive calculations. Partial distance and pixel spiral summation order are used to reduce the time spent on error summation. Experimental results show that significant improvements in performance can be made. The encoding time using a 128 × 128 window is reduced from 14 sec/frame, in the sequential case, to 3.2 sec/frame, about five times faster, using six Pentium 450 MHz in parallel.

References (21)

  1. ISO/IEC 13818-2, Information technology-Generic coding of moving pictures and associated audio-Part 2, video, 1995.
  2. K.R. Rao & Z.S. Bojkovic, Packet video communications over ATM networks (Upper Saddle River, NJ: Prentice Hall, 2000).
  3. N. Ahmed, T. Natarajan, & K.R. Rao, Discrete cosine trans- form, IEEE Trans. Computers, C-23, January 1974, 90-93.
  4. R.C. Gonzales & R.E. Woods, Digital image processing (Reading, MA: Addison Wesley, 1992).
  5. D.M. Barbosa, J.P. Kitajima, & W. Meira Jr., Parallelizing MPEG video encoding using multiprocessors, Proc. XII Brazilian Symp. on Computer Graphics and Image Processing, Campinas, Brazil, 1999, 215-222.
  6. M.K. Steliaros, G.R. Martin, & R.A. Packwood, Parallelization of block matching motion estimation algorithms, Research Rep. RR-320, Department of Computer Science, University of Warwick, Coventry, UK, January 1997.
  7. S.M. Akramullah, I. Ahmad, & M.L. Liou, Performance of software-based MPEG-2 video encoder on parallel and dis- tributed systems, IEEE Trans. on Circuits and Systems for Video Technology, 7 (4), 1997, 687-695.
  8. F. Dufaux & F. Moscheni, Motion estimation techniques for digital TV: A review and a new contribution, IEEE Proc., 83 (6), 1995, 858-876.
  9. Y.S. Chen, Y.P. Hung, & C.S. Fuh, Fast block-matching algorithm based on the winner-update strategy, IEEE Trans. on Image Processing, 10 (8), 2001, 1212-1222.
  10. A. Chimienti, C. Ferraris, & D. Pau, A complexity-bounded motion estimation algorithm, IEEE Trans. on Image Processing, 11 (4), 2002, 387-392.
  11. V.G. Moshnyaga, A new computationally adaptive formulation of block-matching motion estimation, IEEE Trans. on Circuits and Systems for Video Technology, 11 (1), 2001, 118-124.
  12. Y.K. Lai, A memory-efficient motion estimator for three step search block-matching algorithm, IEEE Trans. on Consumer Electronics, 47 (3), 2001, 644-651.
  13. H. Gharavi & H.R. Alikhani, Pel-recursive motion estimation algorithm, Electronic Letters, 37 (21), 2001, 1285-1286.
  14. R. Srinivasan & K.R. Rao, Predictive coding based on efficient motion estimation, IEEE Trans. on Communications, COM- 33 (8), 1985, 888-896.
  15. T. Koga, K. Ilnuma, A. Hirano, I. Iijima, & T. Isshiguro, Motion compensated interframe coding for video conferencing, Proc. Nat. Telecommunications Conf., Vol. 4, New York, 1981, G.5.3.1-5.
  16. M. Ghanbari, The cross-search algorithm for motion estimation, IEEE Trans. on Communications, 38 (7), 1990, 950-953.
  17. B. Liu & A. Zaccarin, New fast algorithms for the estimation of block motion vectors, IEEE Trans. Circuits Syst. Video Technologies, 3 (2), 1993, 148-157.
  18. C.D. Bei & R.M. Gray, An improvement of the minimum distortion encoding algorithm for vector quantization, IEEE Trans. on Communications, COM-33, October 1985, 1132- 1133.
  19. A. Gersho & R.M. Gray, Vector quantization and signal com- pression (Boston, MA: Kluwer, 1992).
  20. A.L. Beguelin, J.J. Dongarra, G.A. Geist, W.C. Jiang, R.J. Manchek, B.K. Moore, & V.S. Sunderam, PVM: Parallel Virtual Machine-A user's guide and tutorial for networked parallel computing (Cambridge, MA: MITPress, 1994).
  21. MPEG Software Simulation Group, http://www.mpeg.org/ MSSG.