[:en]Linear video coding is a joint source-channel coding approach to the problem of video delivery through unreliable channels.

The scenario consists in a single source sending the video to several receivers. For example, we could consider a remotely-controled vehicle sending the video to multiple antennas (base stations) for improved resiliency; or to the more classical video distribution service to mobile users.

Classical systems are based on digital video compression (e.g., H.264 or HEVC) on a suitable protocol stack at transport and network levels. However this implies that the coding choices (compression rate, channel coding rate) are decided a priori and could misfit with the actual channel conditions. For example, some user may suffer from digital cliff while other may have a very good channel and yet not taking fully benefit of it since the design choices are based on more pessimistic hypotheses.

LVC solve this problem by using a fully linear coding system. A suitable transform is applied to the video signal, such to concentrate the information in a few coefficients. Then the relevant coefficients are sent using a very dense modulation (or, in principle, by analogical modulation of OFDM carriers). Since the full system is linear, users with good channel will have good quality of the received video. Users with worse channel still will receive some information.

As for its very simple nature, LVC needs many improvement to be fully competitive with the latest video compression and transmission systems. Therefore, it is not surprising that a large amount of research has been lately devoted to this area.

We mention in the following some of the recent papers on this issue.

Our contributions to the field consist in power allocation techniques that optimize the quality of the received signal; and dimensionalty reduction tools which increase the bandwidth of the transmission system.

Our publications

[Cagnazzo2015] M. Cagnazzo, M. Kieffer. « Shannon-Kotelnikov Mappings for Softcast-based Joint Source-Channel Video Coding ». In IEEE International Conference on Image Processing, vol. 1, pp. 1-4, September 2015. Québec City, Canada.
[Zheng2016] S. Zheng, M. Antonini, M. Cagnazzo, L. Guerrieri, M. Kieffer, I. Nemoianu, R. Samy, B. Zhang. « Softcast with per-carrier Power-Constrained Channel ». In IEEE International Conference on Image Processing, vol. 1, pp. 1-4, September 2016. Phoenix, AZ, USA.
[Zheng2018] S. Zheng, M. Cagnazzo, M. Kieffer. « Precoding matrix design in linear video coding ». IEEE International Conference on Acoustics, Speech and Signal Processing, April 2018.
[Zheng2019a] S. Zheng, M. Cagnazzo, M. Kieffer. « Channel Impulsive Noise Mitigation for Linear Video Coding Schemes ». In IEEE International Conference on Acoustics, Speech and Signal Processing, vol. 1, pp. 2347-2351, May 2019. Brighton, UK.
[Zheng2019b] S. Zheng, M. Cagnazzo, M. Kieffer. « Optimal and Suboptimal Channel Precoding and Decoding Matrices for Linear Video Coding ». In Elsevier Signal Processing: Image Communication, vol. 1, no. 6, pp. 1-12, June 2019.
[Zheng2019c] S. Zheng, M. Cagnazzo, M. Kieffer. « Channel Impulsive Noise Mitigation for Linear Video Coding Schemes ». In IEEE Transactions on Circuits and Systems for Video Technology,  Sept 2019.

References

[Cagnazzo2015] M. Cagnazzo, M. Kieffer. « Shannon-Kotelnikov Mappings for Softcast-based Joint Source-Channel Video Coding ». In IEEE International Conference on Image Processing, vol. 1, pp. 1-4, September 2015. Québec City, Canada.
[Cui2013] H. Cui, Z. Song, Z. Yang, C. Luo, R. Xiong, and F. Wu, « Cactus: a hybrid digital-analog wireless video communication system, » in 16th ACM International Conference on Modeling, Analysis and Simulation of Wireless and Mobile Systems (MSWiM), Barcelona, Spain, November 3-8, 2013, 2013, pp. 273–278.
[Cui2014] H. Cui, C. Luo, C. W. Chen, and F. Wu, « Robust uncoded video transmission over wireless fast fading channel, » in IEEE Conference on Computer Communications (INFOCOM), Toronto, Canada, April 27 – May 2, 2014, pp. 73–81.
[Cui2015] H. Cui, R. Xiong, C. Luo, Z. Song, and F. Wu, « Denoising and resource allocation in uncoded video transmission, » IEEE Journal of Selected Topics in Signal Processing, vol. 9, no. 1, pp. 102–112, 2015.
[Fan2011] Fan, X., Wu, F., & Zhao, D. (2011, December). D-cast: DSC based soft mobile video broadcast. In Proceedings of the 10th International Conference on Mobile and Ubiquitous Multimedia (pp. 226-235). ACM.
[Fan2012] Xiaopeng Fan, Ruiqin Xiong, Feng Wu, and Debin Zhao. Wavecast: Wavelet based wireless video broadcast using lossy transmission. In Visual Communications and Image Processing (VCIP), 2012 IEEE, pages 1-6. IEEE, 2012.
[Fan2012a] X. Fan, F. Wu, D. Zhao, C. O. Au, and W. Gao, « Disributed soft video broadcast (DCast) with explicit motion, » in Proceedings of Data Compression Conference, 2012, pp. 199–208.
[Fan2012b] X. Fan, R. Xiong, F. Wu, and D. Zhao, « Wavecast: Wavelet based wireless video broadcast using lossy transmission, » in IEEE Visual Communications and Image Processing (VCIP), 2012, pp. 1–6.
[Fan2013] Xiaopeng Fan, Feng Wu, Debin Zhao, and Oscar C Au. Distributed wireless visual communication with power distortion optimization. IEEE Transactions on Circuits and Systems for Video Technology, 23(6):1040-1053, 2013
[Fan2015] X. Fan, R. Xiong, D. Zhao and F. Wu, « Layered Soft Video Broadcast for Heterogeneous Receivers, » in IEEE Transactions on Circuits and Systems for Video Technology, vol. 25, no. 11, pp. 1801-1814, Nov. 2015.
[Fujihashi2018] T. Fujihashi, T. Koike-Akino, T. Watanabe, and P. V. Orlik, “High-Quality Soft Video Delivery With GMRF-Based Overhead Reduction,” IEEE Transactions on Multimedia, vol. 20, no. 2, pp. 473–483, Feb. 2018.
[He2015] D. He, C. Luo, C. Lan, F.Wu, and W. Zeng, « Structure-preserving hybrid digital-analog video delivery in wireless networks, » IEEE Transactions on Multimedia, vol. 17, no. 9, pp. 1658–1670, Sept 2015.
[Jakubczak 2010] S. Jakubczak and D. Katabi, « Softcast: one-size-fits-all wireless video, » in Proceedings of the ACM SIGCOMM 2010 conference, ser. SIGCOMM ’10.New York, NY, USA: ACM, pp. 449-450, 2010.
[Jakubczak2011] S. Jakubczak and D. Katabi, “A cross-layer design for scalable mobile video,” in Proc. international conference on Mobile computing and networking (MobiCom ’11), New York, NY, USA, 2011, pp. 289–300.
[Kong2015] X. Kong and H. Lu, « Joint power allocation for hybrid digital-analog transmission in relay networks, » Global Communications Conference (GLOBECOM), Dec 2015.
[Li2016] Y. Li, Y. Liu, Y. Wang, and Z. Li, “Visual information exploited hybrid digital-analog scheme for wireless video multicast,” in Visual Communications and Image Processing (VCIP), 2016, 2016, pp. 1–4.
[Liang2017a] F. Liang, C. Luo, R. Xiong, W. Zeng, and F. Wu, “Superimposed Modulation for Soft Video Delivery with Hidden Resources,” IEEE Transactions on Circuits and Systems for Video Technology, vol. PP, no. 99, pp. 1–1, doi: 10.1109/TCSVT.2017.2703605.
[Liang2018] Liang, F., Luo, C., Xiong, R., Zeng, W., & Wu, F. Hybrid Digital-Analog Video Delivery with Shannon-Kotel’nikov Mappings. IEEE Transactions on Multimedia (2018)
[Liu2012] X. Liu, W. Hu, Q. Pu, F. Wu, and Y. Zhang, « ParCast: soft video delivery in mimo-ofdm wlans, » in Proceedings of Internation Conference on Mobile Computing and Networking, 2012, pp. 233–244.
[Liu2014] X. Liu, W. Hu, C. Luo, Q. Pu, F. Wu, and Y. Zhang, « ParCast+:Parallel video unicast in MIMO-OFDM wlans, » IEEE Transactions on Multimedia, vol. 16, no. 7, pp. 2038–2051, 2014.
[Song2014a] Z. Song, R. Xiong, X. Fan, S. Ma, and W. Gao, « Transform domain energy modeling of natural images for wireless SoftCast optimization, » in IEEE International Symposium on Circuits and Systems (ISCAS), Melbourne, Australia, June 2014, pp. 1114–1117.
[Song2014b] Z. Song, R. Xiong, S. Ma, X. Fan, and W. Gao, « Layered image/video SoftCast with hybrid digital analog transmission for robust wireless visual communication, » in IEEE International Conference on Multimedia and Expo (ICME), Chengdu, China, Jul. 2014.
[Trioux2018] A. Trioux, F.-X. Coudoux, P. Corlay, M. Gharbi , “A Comparative Preprocessing Study for SoftCast Video Transmission,” in IEEE 9th International Symposium on Signal, Image, Video and Communications (ISIVC) 2018.
[Trioux2019]Anthony Trioux, François-Xavier Coudoux, Patrick Corlay, Mohamed Gharbi: A Reduced Complexity/Side Information Preprocessing Method for High Quality Softcast-Based Video Delivery. EUVIP 2019: 205-210
[Trioux2020] Anthony Trioux, François-Xavier Coudoux, Patrick Corlay, Mohamed Gharbi: Temporal information based GoP adaptation for linear video delivery schemes. Signal Process. Image Commun. 82: 115734 (2020)
[Wu2014] F. Wu, X. Peng, and J. Xu, « LineCast: Line-based distributed coding and transmission for broadcasting satellite images, » IEEE Transactions on Image Processing, vol. 23, no. 3, pp. 1015–1027, 2014.
[Xiong2013a] R. Xiong, F. Wu, J. Xu, an d W. Gao, « Performance analysis of transform in uncoded wireless visual communication, » in IEEE International Symposium on Circuits and Systems (ISCAS), Beijing, China, May 2013, pp. 1159–1162.
[Xiong2013b] R. Xiong, F. Wu, X. Fan, C. Luo, S. Ma, and W. Gao, « Power-distortion optimization for wireless image/video SoftCast by transform coefficients energy modeling with adaptive chunk division, » in IEEE Visual Communications and Image Processing (VCIP), 2013, pp. 1–6.
[Xiong2014] R. Xiong, J. Zhang, F. Wu, and W. Gao, « High quality image reconstruction via non-local collaborative estimation for wireless image/video SoftCast, » IEEE International Conference on Image Processing (ICIP), pp. 2542–2546, Oct 2014.
[Xiong2016] R. Xiong, F. Wu, J. Xu, X. Fan, C. Luo, and W. Gao, « Analysis of decorrelation transform gain for uncoded wireless image and video communication, » IEEE Transactions on Image Processing, vol. 25, no. 4, pp. 1820–1833, April 2016.
[Xiong2017] R. Xiong, J. Zhang, F. Wu, J. Xu, and W. Gao, « Power distortion optimization for uncoded linear transformed transmission of images and videos, » IEEE Transactions on Image Processing, vol. 26, no. 1, pp. 222–236, 2017.
[Yu2014] L. Yu, H. Li, and W. Li, « Wireless scalable video coding using a hybrid digital-analog scheme, » IEEE Transactions on Circuits and Systems for Video Technology, vol. 24, no. 2, pp. 331–345, Feb 2014.
[Yun2015] S. Yun, D. Kim, X. Lu, and L. Qiu, « Optimized layered integrated video encoding, » IEEE Conference on Computer Communications (INFOCOM), pp. 19–27, April 2015
[Zhao2017] J. Zhao, R. Xiong, C. Luo, F. Wu, and W. Gao, “Wireless image and video soft transmission via perception-inspired power distortion optimization,” in 2017 IEEE Visual Communications and Image Processing (VCIP), 2017, pp. 1–4.
[Zheng2016] S. Zheng, M. Antonini, M. Cagnazzo, L. Guerrieri, M. Kieffer, I. Nemoianu, R. Samy, B. Zhang. « Softcast with per-carrier Power-Constrained Channel ». In IEEE International Conference on Image Processing, vol. 1, pp. 1-4, September 2016. Phoenix, AZ, USA.
[Zheng2018] S. Zheng, M. Cagnazzo, M. Kieffer. « Precoding matrix design in linear video coding ». IEEE International Conference on Acoustics, Speech and Signal Processing, April 2018.
[Zheng2019a] S. Zheng, M. Cagnazzo, M. Kieffer. « Channel Impulsive Noise Mitigation for Linear Video Coding Schemes ». In IEEE International Conference on Acoustics, Speech and Signal Processing, vol. 1, pp. 2347-2351, May 2019. Brighton, UK.
[Zheng2019b] S. Zheng, M. Cagnazzo, M. Kieffer. « Optimal and Suboptimal Channel Precoding and Decoding Matrices for Linear Video Coding ». In Elsevier Signal Processing: Image Communication, vol. 1, no. 6, pp. 1-12, June 2019.
[Zheng2019c] S. Zheng, M. Cagnazzo, M. Kieffer. « Channel Impulsive Noise Mitigation for Linear Video Coding Schemes ». In IEEE Transactions on Circuits and Systems for Video Technology,  Sept 2019[:]