A New Fast Motion Search Algorithm Using Motion Characteristics

움직임 특성을 이용한 새로운 고속 움직임 예측 방법

  • Published : 2003.03.01

Abstract

Recently we need a faster and more accurate motion vector search algorithm for ASIC(Application Specific IC) or small systems. Block motion estimation using Full Search(FS) algorithm provides the best visual quality and PSNR, but it requires intensive computations. The previously proposed fast algorithms reduced the number of computations by limiting the number of searching locations. This is accomplished at the expense of less accuracy of motion estimation and gives rise to an appreciably higher SAD(Sum of Absolute Difference) for motion compensated images. In this paper we exploit the spatial correlation of motion vectors and present a fast motion estimation scheme which uses the predicted motion vector(PMV). The PMV scheme is more clear and simpler than the previously proposed algorithms which also use adjacent motion vectors. Simulation results with standard video sequences show that the PMV scheme is faster and more accurate than other algorithms such as Nearest-Neighbors Search(NNS) algorithm.

최근 들어 ASIC(Application Specific IC)이나 소형 시스템에서 사용할 수 있는 더 빠르고 정확한 움직임 벡터 예측방법이 요구되고 있다. 전역탐색(Full Search: FS) 방법은 탐색영역의 모든 화소들을 탐색하여 움직임 벡터를 예측하는 방법으로 화질과 PSNR은 좋지만 반면에 많은 계산량이 요구된다. 기존의 고속 알고리즘들은 탐색 회수를 제한함으로써 계산량을 줄였기 때문에 움직임 벡터 예측의 정확도가 낮고, 움직임 보상시 SAD(Sum of Absolute Difference) 값이 높아지는 것을 감수해야한다. 본 논문에서는 영상에서의 현재 블록과 주변 블록과의 공간적인 상관도를 고려하여 예측된 움직임 벡터 (Predicted Motion Vector: PMV)를 이용하는 고속 움직임 탐색 방법을 제안한다. PMV 방법은 주변 블록의 움직임 벡터를 이용한 기존 방법들 보다 명확하고 간결하게 탐색을 수행할 수 있다. PMV 방법이 대표적인 기존 방법인 Nearest-Neighbors Search(NNS) 방법보다 속도 및 정확도 면에서 성능이 양호함을 대표적인 실험 시퀀스를 통하여 보였다.

Keywords

References

  1. A.M. Tekalp, Digital Video Processing, Prentice Hall, 1995
  2. ISO/IEC JTC1/SC29/WG11, Generic coding of moving pictures and associated audio, Part 2:Video, IS 11172-2, March 1995
  3. ISO/IEC JTC1/SC29/WG11, Generic coding of moving pictures and associated audio, Part 2:Video, IS 13818-2, March 1995
  4. ISO/IEC JTC1/SC29/WG11, Generic coding of moving pictures and associated audio, Part 2:Visual, IS 14496-2, Nov 1998
  5. ITU-T, 'Video Coding for Low Bitrate Communication', Draft Recommendation H.263, July, 1995
  6. ITU-T, 'Video Coding for Low Bitrate Communication', Draft Recommendation H.263+, Jan., 1998
  7. ITU-T, 'Video Coding for Low Bitrate Communication', Draft Recommendation H.26L, July, 2001
  8. T. Koga, K. Iinuma, A. Hirano, Y. Iijima, T. Ishiguro, 'Motion-compensated interframe coding for video conferencing', Proc. NTC81, New Orleans, LA, pp. C9.6.1-C9.6.5, Nov. 1981
  9. J. R. Jain, A. K. Jain, 'Displacement measurement and its application in interframe image coding', IEEE Trans. Commun., Vol. COM-29, pp. 1799-1808, Dec. 1981 https://doi.org/10.1109/TCOM.1981.1094950
  10. A. Puri, H. M. Hang. and D.L. Schilling, 'An efficient block matching algorithm for motion compensated coding', Intl. Conf. Acoust., Speech, and Signal Process, pp. 1063-1066, Dallas, TX, April. 1987
  11. M. Ghanbari, 'The cross-search algorithm for motion estimation', IEEE Trans. Commun, Vol.38, No.7, pp. 950-953, July 1990 https://doi.org/10.1109/26.57512
  12. R.Li, B.Zeng, and M. L. Liou, 'A New Three-step Search Algorithm for Block Motion Estimation', IEEE. Trans. on Circuits Syst. Video Tech, Vol. 4, pp. 438-442, Oct.1994 https://doi.org/10.1109/76.313138
  13. L. M. Po and W. C. Ma, 'A novel four-step search algorithm for fast block motion estimation', IEEE. Trans. on Circuits Syst. Video Tech, Vol. 6, No. 3, pp. 313-317, Jun. 1996 https://doi.org/10.1109/76.499840
  14. J. B. Xu, L. M. Po, C. K. Cheung, 'A new prediction model search algorithm for fast block motion estimation', Proc. ICIP, pp. 610-613, 1997 https://doi.org/10.1109/ICIP.1997.632195
  15. M. Gallant, G. Cote, and F. Kossentini, 'An Efficient Computation-Constrained Block-Based Motion Estimation Algorithm for Low Bit Rate Video Coding', IEEE Tr. on Image Processing, Vol. 8, No. 12, December 1999 https://doi.org/10.1109/83.806627
  16. G. Slavenburg et al., 'TriMedia, TM1300 Preliminary Data Book,' Philips Electronics North America Corporation, TriMedia Product Group, 811 E. Arques Avenue, Sunnyvale, CA, 1999
  17. 'Equator Hardware Reference MAP-CA DSP Datasheet', Equator Technologies, Inc., and Hitachi, Ltd., 2001
  18. Zhou Wang and Alan C.Bovik, 'A universal image quality index,' IEEE Signal Processing Letters, vol. 9, no. 3, pp. 81-84, MARCH 2002 https://doi.org/10.1109/97.995823
  19. IEEE Signal Processing Letters v.9 no.3 A universal image quality index Zhou Wang;Alan C.Bovik