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Fractional Motion Estimation

  • Youn-Long Steve Lin
  • Chao-Yang Kao
  • Huang-Chih Kuo
  • Jian-Wen Chen
Chapter

Abstract

Motion estimation in H.264/AVC supports quarter-pixel precision and is usually carried out in two phases: integer motion estimation (IME) and fractional motion estimation (FME). We have talked about IME in Chap.3. After IME finds an integer motion vector (IMV) for each of the 41 subblocks, FME performs motion search around the refinement center pointed to by IMV and further refines 41 IMVs into fractional MVs (FMVs) of quarter-pixel precision. FME interpolates half-pixels using a six-tap filter and then quarter-pixels a two-tap one. Nine positions are searched in both half refinement (one integer-pixel search center pointed to by IMV and 8 half-pixel positions) and then quarter refinement (1 half-pixel position and 8 quarter-pixel positions). The position with minimum residual error is chosen as the best match. FME can significantly improve the video quality (+0.3 to+0.5dB) and reduce bit-rate (20–37%) according to our experimental results. However, our profiling report shows that FME consumes more than 40% of the total encoding time. Therefore, an efficient hardware accelerator for FME is indispensable.

Keywords

Motion Estimation Video Quality Hardware Cost Reference Software Hardware Accelerator 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

References

  1. 10.
    Chen T-C, Huang Y-W, Chen L-G (2004) Fully utilized and reusable architecture for fractional motion estimation of H.264/AVC. In: Proceedings of IEEE international conference on acoustics, speech, and signal processing, Montreal, Canada, May 2004, pp 9–12Google Scholar
  2. 18.
    Yang C, Goto S, Ikenaga T (2006) High performance VLSI architecture of fractional motion estimation in H.264 for HDTV. In: Proceedings of IEEE international symposium on circuits and systems, Island of Kos, Greece, May 2006, pp 2605–2608Google Scholar
  3. 25.
    Kao C-Y, Kuo H-C, Lin Y-L (2006) High performance fractional motion estimation and mode decision for H.264/AVC. In: Proceedings of IEEE international conference on multimedia and expo, Toronto, Canada, July 2006, pp 1241–1244Google Scholar
  4. 28.
    Kao C-Y, Wu C-L, Lin Y-L (in press) A high performance three-engine architecture for H.264/AVC fractional motion estimation. IEEE Trans Very Large Scale Integr SystGoogle Scholar
  5. 34.
    Komerek T, Pirsch P (1989) Array architectures for block matching algorithms. IEEE Trans Circuits Syst Video Technol 36(10):1301–1308Google Scholar
  6. 35.
    Kuo T-Y, Lin Y-K, Chang T-S (2007) SIFME: a single iteration fractional-pel motion estimation algorithm and architecture for HDTV sized H.264 video coding. In: Proceedings of IEEE international conference on acoustics, speech, and signal processing, Hawaii, USA, April 2007, pp 1185–1188Google Scholar
  7. 63.
    Su C-L, Yang W-S, Chen Y-L, Li Y, Chen C-W, Guo J-I, Tseng S-Y (2006) Low complexity high quality fractional motion estimation algorithm and architecture design for H.264/AVC. In: Proceedings of IEEE Asia Pacific symposium on circuits and systems, Singapore, December 2006, pp 578–581Google Scholar
  8. 73.
    Wang Y-J, Cheng C-C, Chang T-S (2007) A fAST aLGORITHM AND iTS VLSI architecture for fractional motion estimation for H.264/MPEG-4 AVC video coding. IEEE Trans Circuits Syst Video Technol 17(5):578–583Google Scholar
  9. 77.
    Wu C-L, Kao C-Y, Lin YL (2008) A high performance three-engine architecture for H.264/AVC fractional motion estimation. In: Proceedings of IEEE international conference on multimedia and expo, Hanover, Germany, June 2008, pp 133–136Google Scholar

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Youn-Long Steve Lin
    • 1
  • Chao-Yang Kao
    • 1
  • Huang-Chih Kuo
    • 1
  • Jian-Wen Chen
    • 1
  1. 1.Dept. Computer ScienceNational Tsing Hua UniversityHsinChuTaiwan R.O.C.

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