Journal of Broadcast Engineering (방송공학회논문지)

The Korean Institute of Broadcast and Media Engineers (한국방송∙미디어공학회)
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A Perceptual Rate Control Algorithm with S-JND Model for HEVC Encoder

S-JND 모델을 사용한 주관적인 율 제어 알고리즘 기반의 HEVC 부호화 방법

  • Kim, JaeRyun (Dept. of Computer Engineering, Kwangwoon University) ;
  • Ahn, Yong-Jo (Dept. of Computer Engineering, Kwangwoon University) ;
  • Lim, Woong (Dept. of Computer Engineering, Kwangwoon University) ;
  • Sim, Donggyu (Dept. of Computer Engineering, Kwangwoon University)
  • 김재련 (광운대학교 컴퓨터공학과) ;
  • 안용조 (광운대학교 컴퓨터공학과) ;
  • 임웅 (광운대학교 컴퓨터공학과) ;
  • 심동규 (광운대학교 컴퓨터공학과)
  • Received : 2016.08.04
  • Accepted : 2016.09.20
  • Published : 2016.11.30
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Abstract

This paper proposes the rate control algorithm based on the S-JND (Saliency-Just Noticeable Difference) model for considering perceptual visual quality. The proposed rate control algorithm employs the S-JND model to simultaneously reflect human visual sensitivity and human visual attention for considering characteristics of human visual system. During allocating bits for CTU (Coding Tree Unit) level in a rate control, the bit allocation model calculates the S-JND threshold of each CTU in a picture. The threshold of each CTU is used for adaptively allocating a proper number of bits; thus, the proposed bit allocation model can improve perceptual visual quality. For performance evaluation of the proposed algorithm, the proposed algorithm was implemented on HM 16.9 and tested for sequences in Class B and Class C under the CTC (Common Test Condition) RA (Random Access), Low-delay B and Low-delay P case. Experimental results show that the proposed method reduces the bit-rate of 2.3%, and improves BD-PSNR of 0.07dB and bit-rate accuracy of 0.06% on average. We achieved MOS improvement of 0.03 with the proposed method, compared with the conventional method based on DSCQS (Double Stimulus Continuous Quality Scale).

본 논문에서는 인지 화질을 고려하기 위해 S-JND 모델 기반의 율 제어 알고리즘을 제안한다. 제안하는 율 제어 알고리즘은 인간이 가지는 시각 시스템의 특징을 반영하기 위하여 시각적 민감도와 시각적 관심도를 동시에 반영할 수 있도록 제작된 S-JND (Saliency-Just Noticeable Difference) 모델을 사용한다. 율 제어 알고리즘을 통해 비트를 분배하는 과정에서 픽쳐 내에 존재하는 각 CTU (Coding Tree Unit)가 가지는 S-JND threshold를 구한다. 각 CTU의 threshold는 적응적으로 적절한 비트를 분배하는데 사용되고, 따라서 제안하는 비트 분배 모델은 인지 화질을 향상 시킬 수 있다. 제안하는 방법의 성능 검증을 위해서 제안하는 방법을 HM 16.9에 구현하였으며, CTC (Common Test Condition) RA (Random Access), Low-delay B와 Low-delay P의 경우에 Class B와 Class C 영상들에 대해 실험 하였다. 실험 결과, 제안하는 방법은 기존 율 제어 알고리즘 대비 평균 2.3%의 비트율이 감소했고 BD-PSNR은 약 0.07dB 향상이 있었으며 비트 정확도 또한 0.06% 정도 증가하였다. DSCQS (Double Stimulus Continuous Quality Scale) 방법으로 측정한 결과, 제안하는 방법은 기존 방법 대비 0.03 MOS (Mean Opinion Score) 향상을 보였다.

Keywords

References

  1. G. J. Sullivan, J. Ohm, W. J. Han and T. Wiegand, "Overview of the High Efficiency Video Coding (HEVC) standard," in Circuits and Systems for Video Technology, IEEE Transactions on, vol. 22, no. 12, pp. 1649-1668, Dec. 2012. https://doi.org/10.1109/TCSVT.2012.2221191
  2. H. H. Jo, E. K. Ryu, J. H. Nam, D. G. Sim, D. H. Kim and J. H. Song, "Parallel method for HEVC deblocking filter based on coding unit depth information," Journal of Broadcast Engineering, vol. 17, no. 5, pp. 742-755, Sep. 2012. https://doi.org/10.5909/JBE.2012.17.5.742
  3. Y. J. Ahn, T. J. Hwang, D. K. Lee, S. M. Kim, S. J. Oh and D. G. Sim, "Study of parallelization methods for real-time HEVC encoder implementation," Journal of Broadcast Engineering, vol. 18, no. 6, pp. 835-849, Nov. 2013. https://doi.org/10.5909/JBE.2013.18.6.835
  4. Y. J. Ahn and D. G. Sim, "Intra block copy analysis to improve coding efficiency for HEVC screen content coding," Journal of Broadcast Engineering, vol. 20, no. 1, pp. 57-67, Jan. 2015. https://doi.org/10.5909/JBE.2015.20.1.57
  5. Y. J. Ahn, S. J. Park and D. G. Sim, "Implementation and commercialization techniques of HEVC codec," The Journal of Korea Institute of Electronics Engineers, vol. 41, no. 19, pp. 89-97, Oct. 2014.
  6. D. G. Sim and H. H. Jo, "Understanding of HEVC standard and technology," HongRung Publishing Company, Korea, 2015.
  7. Q. Lin and G. Feng, "The bit allocation and RDO mode based rate control algorithm," 2010 International Conference on Anti-Counterfeiting Security and Identification in Communication (ASID), pp. 154-157, Jul. 2010.
  8. J. Kim, W. Lim, J. Y. Lim and D. G. Sim, "A perceptual rate control algorithm based on S-JND model," in Winter Conference on The Korean Institute of Communications and Information Sciences, Jan. 2016.
  9. W. Lim, H. Jo and D. Sim, "Perceptual coding based on JND model for High Efficiency Video Coding," in International Conference on 3 Dimensional Systems and Applications, Seoul, Korea, 2014.
  10. Guan-Lin Wu, Yu-Jie Fu, Sheng-Chieh Huang and Shao-Yi Chien, "Perceptual quality-regulable video coding system with region-based rate control scheme," IEEE Transactions on Image Processing, vol. 22, no. 6, Jun. 2013.
  11. X. Wang, L. Su, Q. Huang, C. Liu and L. Duan, "Motion based perceptual distortion and rate optimization for video coding," 2012 IEEE International Conference on Multimedia and Expo. (ICME), pp. 1061-1066, Jul. 2012.
  12. B. Li, H. Li, L. Li and J. Zhang, "Rate control by R-lambda model for HEVC," JCT-VC of ITU-T SG16 WP3 and ISO/IEC JTC1/SC29/WG11, JCTVC-K0103, Shanghai, China, Oct. 2012.
  13. G. J. Sullivan and R. Wiegand, "Rate-distortion optimization for video compression," IEEE Signal Processing Magazine, vol. 15, no. 6, pp. 74-90, Nov. 1998. https://doi.org/10.1109/79.733497
  14. W. Lim and D. G. Sim, "Coding unit-level multi-loop encoding method based on JND for perceptual coding," Journal of the Institute of Electronics and Information Engineers, vol. 52, no. 5, pp. 147-154, May. 2015. https://doi.org/10.5573/ieie.2015.52.5.147
  15. H. Choi, J. Nam, J. Yoo, D. Sim and I. V. Bajic, "Rate control based on unified RQ model for HEVC," JCT-VC of ITU-T SG16 WP3 and ISO/IEC JTC1/SC29/WG11, JCTVC-H0213, San Jose, CA, Jan. 2012.
  16. H. Choi, J. Yoo, J. Nam, D. Sim and I. V. Bajic, "Pixel-wise unified rate-quantization model for multi-level rate control," IEEE Journals & Magazines, vol. 7, no. 6, pp. 1112-1123, 2013.
  17. B. Lin, H. Li, L. Li and J. Zhang, "Lambda domain rate control algorithm for High Efficiency Video Coding," IEEE Transactions on Image Processing, vol. 23, no. 9, pp. 3841-3854, 2014. https://doi.org/10.1109/TIP.2014.2336550
  18. C. Chou and Y. Li, "A perceptually tuned subband image coder based on the measure of Just-Noticeable-Distortion profile," in Circuits and Systems for Video Technology, IEEE Transactions on, vol. 5, no. 6, pp. 467-476, Dec. 1995. https://doi.org/10.1109/76.475889
  19. Z. Wei and K. N. Ngan, "Spatio-temporal Just Noticeable Distortion profile for grey scale image/video in DCT domain," in IEEE Transactions on Circuits and Systems for Video Technology, vol. 19, no. 3, pp. 337-346, Mar. 2009. https://doi.org/10.1109/TCSVT.2009.2013518
  20. F. Bossen, "Common test conditions and software reference configurations," JCT-VC of ITU-T SG16 WP3 and ISO/IEC JTC1/SC29/WG11, JCT-VC H1100, San Jose, CA, Jan. 2012.
  21. G. Bjontegaard, "Calculation of average PSNR differences between RD-curves," ITU-T SG16/Q.6, VCEG-M33, Austin, TX, Apr. 2001.
  22. J. Kim, W. Lim and D. G. Sim, "Rate control encoding method of HEVC for improving perceptual visual quality," in Summer Conference on The Institute of Electronics and Information Engineers, June. 2016.
  23. ITU-R BT.500-11, "Methodology for the subjective assessment of the quality of television pictures," Jan. 2012.