방송공학회논문지 (Journal of Broadcast Engineering)

  • 제28권1호
  • /
  • Pages.100-108
  • /
  • 2023
  • /
  • 1226-7953(pISSN)
  • /
  • 2287-9137(eISSN)
한국방송∙미디어공학회 (The Korean Institute of Broadcast and Media Engineers)
권호 표지
DOI QR코드

DOI QR Code

곱셈 연산을 고려한 고속 역변환 방법

Fast Inverse Transform Considering Multiplications

  • Hyeonju Song (Department of Computer Engineering, Sejong University) ;
  • Yung-Lyul Lee (Department of Computer Engineering, Sejong University)
  • 투고 : 2022.10.26
  • 심사 : 2022.12.09
  • 발행 : 2023.01.30
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

하이브리드 블록 기반 비디오 압축에서 변환 부호화는 공간 영역의 잔차 신호를 주파수 영역으로 변환하여 낮은 주파수 대역에 에너지를 집중시켜 이후 엔트로피 코딩 과정에서 높은 압축률을 달성할 수 있게 한다. 최신 비디오 압축 표준인 VVC(Versatile Video Coding)는 DCT-2(Discrete Cosine Transform type 2), DST-7(Discrete Sine Transform type 7), DCT-8(Discrete Cosine Transform type 8)를 사용하여 주변환을 수행한다. 본 논문에서는 DCT-2, DST-7, DCT-8이 모두 선형 변환임을 고려하여, 선형 변환의 선형성을 이용하여 역변환 시 곱셈 연산량을 줄이는 역변환 방법을 제안한다. 제안하는 역변환 방법은 VVC의 참조 소프트웨어인 VVC Test Model-8.2 (VTM-8.2) 대비 비트율의 증가 없이 부호화 시간과 복호화 시간이 AI(All Intra)에서 평균 26%, 15%, RA(Randon Access)에서 평균 4%, 10% 감소하였다.

In hybrid block-based video coding, transform coding converts spatial domain residual signals into frequency domain data and concentrates energy in a low frequency band to achieve a high compression efficiency in entropy coding. The state-of-the-art video coding standard, VVC(Versatile Video Coding), uses DCT-2(Discrete Cosine Transform type 2), DST-7(Discrete Sine Transform type 7), and DCT-8(Discrete Cosine Transform type 8) for primary transform. In this paper, considering that DCT-2, DST-7, and DCT-8 are all linear transformations, we propose an inverse transform that reduces the number of multiplications in the inverse transform by using the linearity of the linear transform. The proposed inverse transform method reduced encoding time and decoding time by an average 26%, 15% in AI and 4%, 10% in RA without the increase of bitrate compared to VTM-8.2.

키워드

과제정보

본 논문은 (과제명: 5G 연계 초고실감 미디어를 위한 VVC (Vesatile Video Codec) 디코더 IP 개발, 과제고유번호: 1415172976, 과제번호: 20010342) 산업통상자원부에서 지원한 과제로 일부 수행되었다.

참고문헌

  1. B. Bross, J. Chen, S. Liu and Y. -K. Wang, "Versatile Video Coding (Draft 10)", JVET-S2001, Jul.2020
  2. G. J. Sullivan, J. -R. Ohm, W. -J. Han and T. Wiegand, "Overview of the High Efficiency Video Coding (HEVC) Standard," IEEE Transactions on Circuits and Systems for Video Technology, Vol.22, No.12, pp.1649-1668, Dec. 2012 doi: https://doi.org/10.1109/TCSVT.2012.2221191.
  3. Y. -W. Huang et al., "Block Partitioning Structure in the VVC Standard," IEEE Transactions on Circuits and Systems for Video Technology, Vol.31, No.10, pp.3818-3833, Oct. 2021 doi: https://doi.org/10.1109/TCSVT.2021.3088134
  4. J. Pfaff et al., "Intra Prediction and Mode Coding in VVC," IEEE Transactions on Circuits and Systems for Video Technology, Vol.31, No.10, pp.3834-3847, Oct. 2021. doi: https://doi.org/10.1109/TCSVT.2021.3072430
  5. H. Yang et al., "Subblock-Based Motion Derivation and Inter Prediction Refinement in the Versatile Video Coding Standard," IEEE Transactions on Circuits and Systems for Video Technology, Vol.31, No.10, pp. 3862-3877, Oct. 2021. doi: https://doi.org/10.1109/TCSVT.2021.3100744
  6. M. Koo, M. Salehifar, J. Lim and S. -H. Kim, "Low Frequency Non-Separable Transform (LFNST)," 2019 Picture Coding Symposium (PCS), Ningbo, China, pp.1-5, 2019. doi: https://doi.org/10.1109/PCS48520.2019.8954507
  7. M. Karczewicz et al., "VVC In-Loop Filters," IEEE Transactions on Circuits and Systems for Video Technology, Vol.31, No.10, pp.3907-3925, Oct. 2021. doi: https://doi.org/10.1109/TCSVT.2021.3072297
  8. N. Ahmed, T. Natarajan and K. R. Rao, "Discrete Cosine Transform," IEEE Transactions on Computers, Vol.C-23, No.1, pp.90-93, Jan. 1974. doi: https://doi.org/10.1109/T-C.1974.223784
  9. M. Budagavi, A. Fuldseth, G. Bjontegaard, V. Sze and M. Sadafale, "Core Transform Design in the High Efficiency Video Coding (HEVC) Standard," IEEE Journal of Selected Topics in Signal Processing. Vol.7, No.6, pp.1029-1041, Dec. 2013. doi: https://doi.org/10.1109/JSTSP.2013.2270429
  10. X. Zhao et al., "Transform Coding in the VVC Standard," IEEE Transactions on Circuits and Systems for Video Technology, Vol.31, No.10, pp.3878-3890, Oct. 2021. doi: https://doi.org/10.1109/TCSVT.2021.3087706
  11. Z. Zhang et al., "Fast DST-VII/DCT-VIII With Dual Implementation Support for Versatile Video Coding," IEEE Transactions on Circuits and Systems for Video Technology, Vol.31, No.1, pp.355-371, Jan. 2021. doi: https://doi.org/10.1109/TCSVT.2020.2977118
  12. Versatile Video Coding Test Model(VTM) 8.2 https://vcgit.hhi.fraunhofer.de/jvet/VVCSoftware_VTM/-/tree/VTM-8.2
  13. Bossen, F. Boyce, J. Suehring, K. Li, X. Seregin, V, "JVET Common Test Conditions and Software Reference Configurations for SDR Video", JVET-T2010, October 2020.