Efficient High-Speed Intra Mode Prediction based on Statistical Probability

통계적 확률 기반의 효율적인 고속 화면 내 모드 예측 방법

  • Lim, Woong (Dept. of Computer Engineering, Kwangwoon University) ;
  • Nam, Jung-Hak (Dept. of Computer Engineering, Kwangwoon University) ;
  • Jung, Kwang-Soo (Dept. of Computer Engineering, Kwangwoon University) ;
  • Sim, Dong-Gyu (Dept. of Computer Engineering, Kwangwoon University)
  • 임웅 (광운대학교 컴퓨터공학부) ;
  • 남정학 (광운대학교 컴퓨터공학부) ;
  • 정광수 (광운대학교 컴퓨터공학부) ;
  • 심동규 (광운대학교 컴퓨터공학과)
  • Received : 2010.01.21
  • Published : 2010.05.25

Abstract

The H.264/AVC has been designed to use 9 directional intra prediction modes for removing spatial redundancy. It also employs high correlation between neighbouring block modes in sending mode information. For indication of the mode, smaller bits are assigned for higher probable modes and are compressed by predicting the mode with minimum value between two prediction modes of neighboring two blocks. In this paper, we calculated the statistical probability of prediction modes of the current block to exploit the correlation among the modes of neighboring two blocks with several test video sequences. Then, we made the probable prediction table that lists 5 most probable candidate modes for all possible combinatorial modes of upper and left blocks. By using this probability table, one of 5 higher probable candidate modes is selected based on RD-optimization to reduce computational complexity and determines the most probable mode for each cases for improving compression performance. The compression performance of the proposed algorithm is around 1.1%~1.50%, compared with JM14.2 and we achieved 18.46%~36.03% improvement in decoding speed.

H.264/AVC는 공간적 중복성을 제거하기 위하여 9개의 화면 내 예측모드를 사용하도록 설계되었다. 또한, 모드 정보의 전송을 위하여 이웃한 블록의 모드간의 높은 상관도를 사용한다. 모드를 표현할 때, 더 높은 확률을 가진 모드에 더 적은 비트가 할당되며, 이웃한 두 개 블록의 예측모드 간에 최소값을 취하여 예측함으로써 압축된다. 본 논문에서는, 몇 개의 테스트 비디오 시퀀스를 사용하여 왼쪽과 위쪽의 이웃한 두 블록의 모드에 따라서 발생하는 현재 블록의 예측모드에 대한 통계적 확률을 구하였다. 다음으로 왼쪽과 위쪽의 이웃한 두 블록의 예측모드의 모든 조합에 대하여 현재 블록에서 결정될 확률이 가장 높은 5개 모드를 후보 예측모드로 하여 테이블로 구성한다. 이 확률 테이블을 사용하여, 선택된 5개의 후보 모드들만 율-왜곡 최적화를 수행함으로써 부호화 과정을 고속화하고, 각각의 경우에서 가장 높은 발생 확률을 갖는 모드를 most probable mode로 사용하여 모드 정보를 줄임으로써 부호화 성능을 높이는 방법을 제안한다. 제안한 알고리즘의 부호화 성능은 5개 후보 모드의 발생확률의 합이 90%, 85%, 80%이상인 경우에 대하여 JM14.2 대비 각각 1.17%, 1.50%, 1.19% 향상되었으며 부호화 속도는 18.46%, 27.97%, 36.03% 향상되었다.

Keywords

References

  1. Thomas Wiegand, Gary J. Sullivan, Gisle Bjontegaard, and Ajay Luthra, "Overview of the H.264/AVC video coding standard," IEEE trans.on Circuits and Systems for Video Technology,vol. 13, no.7, pp. 560-576, July 2003.
  2. ITU-T Recommendation H.264 & ISO/IEC 14496-10 (MPEG-4) AVC, "Advanced Video Coding for Generic Audiovisual Services," (version 1: 2003, version 2: 2004) version 3: 2005.
  3. Gary J. Sullivan, "The H.264/MPEG4 Advanced Video Coding Standard and its Applications," IEEE Communications Magazine, pp. 134-143, August, 2006.
  4. Iain E.G. Richardson, "H.264 and MPEG-4 video compression for next-generation multimedia" Wiley, pp.177-184, 2003.
  5. ISO/IEC, Generic Coding of Moving Pictures and Associated Audio-Part 2: Video, ISO/IEC 13818-2, 2000.
  6. Arundhati Tamhankar and K. R. Rao, An Overview of H.264/MPEG-4 part 10, 4th EURASIP Conference on Video/Image Processing and Multimedia Communications, vol. 1, pp. 1-51, June 2003.
  7. A Puri, X Chen, A Luthra, "Video coding using the H.264/MPEG-4 AVC compression standard," Signal Processing: Image Communication 19 (2004) pp.793-849, 2004. https://doi.org/10.1016/j.image.2004.06.003
  8. Lain E. G. Richardson, H.264 and MPEG-4 Video Compression, John Wiley & Sons Ltd, pp. 187-198, 2003.
  9. G. Sullivan, T. Wiegand, "Rate-distortion optimization for video compression," IEEE Signal Proc. Magazine, pp. 74-90, November, 1998.
  10. Jun Sung Park, and Hyo Jung Song, "Selective Intra Prediction Mode Decision for H.264/AVC Encoders," World Academy of Science, Engineering and Technology, Volume 13, pp.51-55, Helsinki, Finland, January, 2006.
  11. Takeshi Tsukuba, Isao Nagayoshi, Tsuyoshi Hanamura, Hideyoshi Tominaga, "H.264 Fast Intra-prediction Mode Decision Based on Frequency Characteristic," Proc. of EUSIPCO 2005, Antalya, Turkey, pp. 61-66, September, 2005.
  12. Abderrahmane Elyousfi, Ahmed Tamtaoui, EL Houssine Bouyakhf, "Fast Mode Decision Algorithm for Intra prediction in H.264/AVC Video Coding," IJCSNS-International Journal of Computer Science and Network Security , VOL.7 No.1, pp. 356-364, January 2007.
  13. A. Elyousfi, A. Tamtaoui, and E. Bouyakhf, "A New Fast Intra Prediction Mode Decision Algorithm for H.264/AVC Encoders," Volume 27, pp. 1-7, March, 2007 Amsterdam, The Netherlands
  14. Gisle Bjontegaard, Calculation of average PSNR differences between RD-curves, ITU-T Q.6/SG16 VCEG, VCEG-M33, Texas, USA, April 2001.