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딥 러닝 기반의 이미지와 비디오 압축 기술 분석

A Technical Analysis on Deep Learning based Image and Video Compression

  • 조승현 (한국전자통신연구원 실감AV연구그룹) ;
  • 김연희 (한국전자통신연구원 실감AV연구그룹) ;
  • 임웅 (한국전자통신연구원 실감AV연구그룹) ;
  • 김휘용 (한국전자통신연구원 실감AV연구그룹) ;
  • 최진수 (한국전자통신연구원 실감AV연구그룹)
  • Cho, Seunghyun (Realistic AV Research Group, Electronics and Telecommunications Research Institute) ;
  • Kim, Younhee (Realistic AV Research Group, Electronics and Telecommunications Research Institute) ;
  • Lim, Woong (Realistic AV Research Group, Electronics and Telecommunications Research Institute) ;
  • Kim, Hui Yong (Realistic AV Research Group, Electronics and Telecommunications Research Institute) ;
  • Choi, Jin Soo (Realistic AV Research Group, Electronics and Telecommunications Research Institute)
  • 투고 : 2018.04.09
  • 심사 : 2018.04.13
  • 발행 : 2018.05.30

초록

본 논문에서는 최근 활발히 연구되고 있는 딥 러닝 기반의 이미지와 비디오 압축 기술에 대해 살펴본다. 딥 러닝 기반의 이미지 압축 기술은 심층 신경망에 압축 대상 이미지를 입력하고 반복적 또는 일괄적 방식으로 은닉 벡터를 추출하여 부호화한다. 이미지 압축 효율을 높이기 위해 심층 신경망은 복원 이미지의 화질은 높이면서 부호화된 은닉 벡터가 보다 적은 비트로 표현될 수 있도록 학습된다. 이러한 기술들은 특히 저 비트율에서 기존의 이미지 압축 기술에 비해 뛰어난 화질의 이미지를 생성할 수 있다. 한편, 딥 러닝 기반의 비디오 압축 기술은 압축 대상 비디오를 직접 입력하여 처리하기 보다는 기존 비디오 코덱의 압축 툴 성능을 개선하는 접근법을 취하고 있다. 본 논문에서 소개하는 심층 신경망 기술들은 최신 비디오 코덱의 인루프 필터를 대체하거나 추가적인 후처리 필터로 사용되어 복원 영상의 화질 개선을 통해 압축 효율을 향상시킨다. 마찬가지로, 화면 내 예측 및 부호화에 적용된 심층 신경망 기술들은 기존 화면 내 예측 툴과 함께 사용되어 예측 정확도를 높이거나 새로운 화면 내 부호화 과정을 추가함으로써 압축 효율을 향상 시킨다.

In this paper, we investigate image and video compression techniques based on deep learning which are actively studied recently. The deep learning based image compression technique inputs an image to be compressed in the deep neural network and extracts the latent vector recurrently or all at once and encodes it. In order to increase the image compression efficiency, the neural network is learned so that the encoded latent vector can be expressed with fewer bits while the quality of the reconstructed image is enhanced. These techniques can produce images of superior quality, especially at low bit rates compared to conventional image compression techniques. On the other hand, deep learning based video compression technology takes an approach to improve performance of the coding tools employed for existing video codecs rather than directly input and process the video to be compressed. The deep neural network technologies introduced in this paper replace the in-loop filter of the latest video codec or are used as an additional post-processing filter to improve the compression efficiency by improving the quality of the reconstructed image. Likewise, deep neural network techniques applied to intra prediction and encoding are used together with the existing intra prediction tool to improve the compression efficiency by increasing the prediction accuracy or adding a new intra coding process.

키워드

참고문헌

  1. J. Jiang, "Image compression with neural networks," Signal Processing: Image Communication Vol. 14, No.9, pp. 737-760, July 1999. https://doi.org/10.1016/S0923-5965(98)00041-1
  2. G. Toderici, S. M. O'Malley, S. J. Hwang, D. Vincent, D. Minnen, S. Baluja, M. Covell, and R. Sukthankar, "Variable rate image compression with recurrent neural networks," Proceeding of International Conference on Learning Representations, San Juan, Puerto Rico, May 2016.
  3. G. Toderici, D. Vincent, N. Johnston, S. J. Hwang, D. Minnen, J. Shor, and M. Covell, "Full Resolution Image Compression with Recurrent Neural Networks," Proceeding of IEEE Conference on Computer Vision and Pattern Recognition, Honolulu, USA, pp. 5435-5443, July 2017.
  4. N. Johnston, D. Vincent, D. Minnen, M. Covell, S. Singh, T. Chinen, S. J. Hwang, J. Shor, and G. Toderici, "Improved Lossy Image Compression with Priming and Spatially Adaptive Bit Rates for Recurrent Networks," https://arxiv.org/abs/1703.10114 (Submitted on Mar 29, 2017)
  5. L. Theis, W. Shi, A. Cunningham, and F. Huszar, "Lossy Image Compression with Compressive Autoencoders," Proceeding of International Conference on Learning Representations, Toulon, France, April 2017.
  6. O. Rippel and L. Bourdev, "Real-Time Adaptive Image Compression," Proceedings of the 34th International Conference on Machine Learning, Sydney, Australia, PMLR 70:2922-2930, Aug. 2017.
  7. WebP - A new image format for the Web, https://developers.google.com/speed/webp/BPG image format, http://bellard.org/bpg
  8. I. J. Goodfellow, J. Pouget-Abadie, M. Mirza, B. Xu, D. Warde-Farley, S. Ozair, A. Courville, and Y. Bengio, "Generative adversarial nets", Proceeding of Neural Information Processing Systems, Montreal, Canada, Dec. 2014.
  9. Z. Wang, A. C. Bovik, H. R. Sheikh, and E. P. Simoncelli, "Image quality assessment: from error visibility to structural similarity," IEEE Transactions on Image Processing, Vol. 13, No.4, pp. 600-612, April 2004. https://doi.org/10.1109/TIP.2003.819861
  10. ITU-T and ISO/IEC JTC 1, "High Efficiency video coding," ITU-T Recommendation H.265 and ISO/IEC 23008-2 (MPEG-H Part 2), Third edition: April 2015.
  11. J. Lainema, F. Bossen, W.-J. Han, J. Min, and K. Ugur, "Intra coding of the HEVC standard," IEEE Trans. on Circuits and Systems for Video Technology, vol. 22, no. 12, pp. 1792-1801, 2012. https://doi.org/10.1109/TCSVT.2012.2221525
  12. A. Norkin, G. Bjontegaard, A. Fuldseth, M. Narroschke, M. Ikeda, K. Andersson, M. Zhou, and G. V. der Auwera, "HEVC Deblocking Filter," IEEE Trans. on Circuits and Systems for Video Technology, vol. 22, no. 12, pp. 1746-1754, 2012. https://doi.org/10.1109/TCSVT.2012.2223053
  13. C.-M. Fu, E. Alshina, A. Alshin, Y.-W. Huang, C.-Y. Chen, and C.-Y. Tsai, C.-W. Hsu, S.-M. Lei, J.-H. Park, and W.-J. Han, "Sample Adaptive Offset in the HEVC Standard," IEEE Trans. on Circuits and Systems for Video Technology, vol. 22, no. 12, pp. 1755-1764, 2012. https://doi.org/10.1109/TCSVT.2012.2221529
  14. Y. Dai, D. Liu, and F. Wu, "A Convolutional Neural Network Approach for Post-Processing in HEVC Intra Coding," Proceeding of the 23rd International Conference on Multimedia Modeling, Reykjavik, Iceland, pp. 28-39, Jan. 2017.
  15. J. Kang, S. Kim, and K. M. Lee, "Multi-modal Multi-scale Convolutional Neural Network based In-loop Filter Design for Next Generation Video Codec," Proceeding of IEEE International Conference on Image Processing, Beijing, China, pp. 16-30, Sept. 2017.
  16. T. Wang, M. Chen, and H. Chao, "A Novel Deep Learning-Based Method of Improving Coding Efficiency from the Decoder-end for HEVC," Proceeding of Data Compression Conference, Snowbird, USA pp. 410-419, April 2017.
  17. L. Zhou, X. Song, J. Yao, L. Wang, and F. Chen, "Convolution Neural Network Filter (CNNF) for Intra Frame," JVET-I0022, Joint Video Exploration Team of ISO/IEC and ITU-T, Gwangju, Korea, Jan. 2018.
  18. C. Dong, Y. Deng, C. C. Loy, and X. Tan, "Compression Artifacts Reduction by a Deep Convolutional Network," Proceeding of IEEE International Conference on Computer Vision, Santiago, Chile, pp. 576-584, Dec. 2015.
  19. P. Svoboda, M.Hradis, D.Barina, and P.Zemcik, "Compression Artifacts Removal Using Convolutional Neural Networks," Journal of WSCG, Vol. 24, No.2, pp. 63-72, 2016.
  20. K. Zhang, W. Zuo, Y. Chen, D. Meng, and L. Zhang, "Beyond a Gaussian Denoiser: Residual Learning of Deep CNN for Image Denoising," IEEE Transactions on Image Processing, Vol. 26, No.7, pp. 3142-3155, 2017. https://doi.org/10.1109/TIP.2017.2662206
  21. J. Kim, J. K. Lee, and K. M. Lee, "Accurate image super-resolution using very deep convolutional networks," Proceeding of IEEE Conference on Computer Vision and Pattern Recognition, Las Vegas, USA, pp. 1646-1654, June 2016.
  22. JEM7.0, https://jvet.hhi.fraunhofer.de/svn/svn_HMJEMSoftware/branches/HM-16.6-JEM-7.0-dev/.
  23. J. Li, B. Li, J. Xu, and R. Xiong, "Intra Prediction Using Fully Connected Network for Video Coding," Proceeding of IEEE International Conference on Image Processing, Beijing, China, pp. 1-5, Sept. 2017.
  24. S. Cho, J. Lee, W. Lim, Y. Kim, J. Seok, H. Y. Kim, and J. Choi, "HEVC Intra Prediction through Convolutional Neural Network," 30th Workshop on Image Processing and Image Understanding, Jeju, Korea, Feb. 2018.
  25. Y. Li, D. Liu, H. Li, L. Li, F. Wu, H. Zhang, and H. Yang, "Convolutional Neural Network-Based Block Up-sampling for Intra Frame Coding," IEEE Transactions on Circuits and Systems for Video Technology, (Early Access), July 2017.
  26. C. Dong, C. C. Loy, K. He, and X. Tang, "Learning a deep convolutional network for image super-resolution," in European Conference on Computer Vision, pp. 184-199, Springer, 2014.