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Book chapter

  • B. Geiser, S. Ragot, and H. Taddei "Embedded Speech Coding: From G.711 to G.729.1," Chapter 8 in Advances in Digital Speech Transmission (R. Martin, U. Heute, C. Antweiler, eds.), Wiley, Jan. 2008, pp. 201-248

Journal articles

  1. S. Ragot, B. Kovesi, A. Le Guyader, "Noise Feedback Coding Revisited: Refurbished Legacy Codecs and New Coding Models (invited paper)," ZTE Communications, Special issue on Emerging Technologies for Multimedia Coding, Analysis and Transmission, vol. 10, no. 2, pp. 37-47, June 2012
  2. B. Geiser, P. Jax, P. Vary, H. Taddei, S. Schandl, M. Gartner, C. Guillaumé, and S. Ragot, "Time Domain Bandwidth Extension for Hierarchical Speech and Audio Coding in ITU-T Rec. G.729.1," IEEE Transactions on Speech, Audio and Language Processing, vol. 15, no. 8, pp. 2496-2509, Nov. 2007
  3. S. Ragot, M. Xie, and R. Lefebvre, "Near-Ellipsoidal Voronoi Coding," IEEE Transactions on Information Theory, vol. 49, no. 3, pp. 1815-1820, Jul. 2003
  4. S. Ragot, J.-P. Adoul, and R. Lefebvre, "Hexacode-based quantization of the Gaussian source at 1/2 bit per sample," IEEE Transactions on Communications, vol. 49, no. 12, pp. 2056-2058, Dec. 2001

Conference articles

  1. T. Muller, S. Ragot, Q. Lemesle, P. Philippe, P. Scalart, "Optimized quantization of latent space in neural audio coding (in French)," Proc. GRETSI 2023, Aug./Sept. 2023
  2. S. Ragot, A. Vasilache, "Spherical vector quantization for spatial direction coding," Proc. ICASSP, June 2023
  3. M. Yaoumi, P. Mahé, S. Ragot, "Audio coding by an autoencoder representation of the spectogram (in French)," Proc. GRETSI, Nancy, Sept. 2022
  4. S. Ragot, M. Yaoumi, "On the Quantization of the Uniform Source on the n-Sphere (n=1, 2, 3)," 5th conference on Geometric Science of Information, Paris, July 2021
  5. P. Mahé, S. Ragot, S. Marchand, J. Daniel, "Ambisonic Coding with Spatial Image Correction," Proc. EUSIPCO, Amsterdam, Sept. 2020
  6. V. Lemaire, F. Boitier, J. Pesic, A. Bondu, S. Ragot, F. Clérot, "Proactive Fiber Break Detection Based on Quaternion Time Series and Automatic Variable Selection from Relational Data," Proc. AALTD, Sept. 2019
  7. P. Mahé, S. Ragot, S. Marchand, "First-order ambisonic coding with quaternion-based interpolation of PCA rotation matrices," Proc. EAA Spatial Audio Signal Processing Symposium, Paris, France, Sept. 2019, pp. 7-12
  8. P. Mahé, S. Ragot, S. Marchand, "First-Order Ambisonic Coding with PCA Matrixing and Quaternion-Based Interpolation," Proc. DAFx, Birmingham, UK, Sept. 2019
  9. N. Majed, S. Ragot, L. Gros, X. Lagrange, A. Blanc, "Application-Layer Redundancy for the EVS Codec," Proc. EUSIPCO, Rome, Italy, Sept. 2018, pp. 2090-2094
  10. G. Mittag, S. Möller, V. Barriac, S. Ragot, "Quantifying Quality Degradation of the EVS Super-Wideband Speech Codec," Proc. IEEE QoMEX, Sardinia, Italy, May-June 2018
  11. N. Majed, S. Ragot, X. Lagrange, A. Blanc, J. Dufour, G. Grao, "Experimental evaluation of WebRTC voice quality in LTE coverage tests," Proc. IEEE QoMEX, Erfurt, Germany, May-June 2017
  12. N. Majed, S. Ragot, X. Lagrange, A. Blanc, "Delay and quality metrics in Voice over LTE (VoLTE) networks: an end-terminal perspective," Proc. IEEE ICNC, San Francisco, USA, Jan. 2017
  13. N. Souviraa-Labastie, S. Ragot, "On the applicability of the SBC codec to support super-wideband speech in Bluetooth handsfree communications," Proc. IEEE MMSP, Montreal, Canada, Sept. 2016
  14. M. Kaniewska, S. Ragot, Z. Liu, L. Miao, X. Zhang, J. Gibbs, V. Eksler, "Enhanced AMR-WB Bandwidth Extension in 3GPP EVS Codec," Proc. GlobalSIP, Orlando, Florida, Dec. 2015
  15. M. Dietz, M. Multrus, V. Eksler, V. Malenovsky, E. Norvell, H. Pobloth, L. Miao, Z. Wang, L. Laaksonen, A. Vasilache, Y. Kamamoto, K. Kikuiri, S. Ragot, J. Faure, H. Ehara, V. Rajendran, V. Atti, H. Sung, E. Oh, H. Yuan, "Overview of the EVS codec architecture," Proc. ICASSP, Brisbane, Australia, May 2015
  16. S. Bruhn, H. Pobloth, M. Schnell, B. Grill, J. Gibbs, L. Miao, K. Järvinen, L. Laaksonen, N. Harada, N. Naka, S. Ragot, S. Proust, T. Sanda, I. Varga, C. Greer, M. Jelinek, M. Xie, P. Usai "Standardization of the new 3GPP EVS codec," Proc. ICASSP, Brisbane, Australia, May 2015
  17. D. Virette, Y. Lang, L. Miao, W. Wu, B. Kövesi, C. Lamblin, S. Ragot, "G.722 Annex D and G.711.1 Annex F - New ITU-T stereo codecs," Proc. ICASSP, Vancouver, Canada, May 2013
  18. Lei Miao, Zexin Liu, Chen Hu, V. Eksler, S. Ragot, C. Lamblin, B. Kovesi, Jongmo Sung, M. Fukui, S. Sasaki, Y. Hiwasaki, "G.711.1 Annex D and G.722 Annex B - New ITU-T superwideband codecs," Proc. ICASSP, Prague, Czech Republic, May 2011
  19. B. Kovesi, S. Ragot, C. Lamblin, Lei Miao, Zexin Liu, Chen Hu, "Re-engineering ITU-T G.722: Low delay and complexity superwideband coding at 64 kbit/s with G.722 bitstream watermarking," Proc. ICASSP, Prague, Czech Republic, May 2011
  20. T.M.N. Hoang, S. Ragot,, B. Kövesi, P. Scalart, "Parametric stereo extension of ITU-T G.722 based on a new downmixing scheme," Proc. IEEE MMSP, St Malo, France, Oct. 2010
  21. T.M.N. Hoang, S. Ragot, M. Oger, and M. Antonini, "A new bitplane coder for scalable transform audio coding," Proc. ICASSP, Taipei, Taiwan, April 2009
  22. T.M.N. Hoang, S. Ragot, M. Oger, and M. Antonini, "Nouvelle méthode de codage par plans de bits pour les signaux de parole et audio," Proc. CORESA, Toulouse, France, March 2009 (in French)
  23. S. Bruhn, V. Grancharov, B. Kleijn, J. Klejsa, M. Li, H. Pobloth, S. Ragot, "The FlexCode Speech and Audio Coding Approach," 8th ITG Conference Speech Communication, Aachen, Germany, Oct. 2008
  24. Y. Hiwasaki, S. Sasaki, H. Ohmuro, T. Mori, J. Seong, M.S. Lee, B. Kovesi, S. Ragot, J.-L. Garcia, C. Marro, L. Miao, J. Xu, V. Malenovsky, J. Lapierre, R. Lefebvre, "G.711.1: a wideband extension to ITU-T G.711," EUSIPCO, Lausanne, Switzerland, Aug. 2008
  25. B. Kövesi, S. Ragot, M. Gartner, H. Taddei, "Pre-echo reduction in the ITU-T G.729.1 embedded coder," EUSIPCO, Lausanne, Switzerland, Aug. 2008
  26. T. Vaillancourt, M. Jelinek, A.E. Ertan, J. Stachurski, A. Ramo, L. Laaksonen, J. Gibbs, U. Mittal, S. Bruhn, V. Grancharov, M. Oshikiri, H. Ehara, D. Zhang, F. Ma, D. Virette, S. Ragot, "ITU-T EV-VBR: a robust 8-32 kbit/s scalable coder for error prone telecommunications channels," EUSIPCO, Lausanne, Switzerland, Aug. 2008
  27. B. Kövesi, S. Ragot, A. Le Guyader, "An 64-80-96 kbit/s Scalable Wideband Speech Coding Candidate for ITU-T G.711-WB Standardization," Proc. ICASSP, Las Vegas, Nevada, USA, March-April 2008
  28. B. Kövesi and S. Ragot, "A low complexity packet loss concealment algorithm for ITU-T G.722," Proc. ICASSP, Las Vegas, Nevada, USA, March-April 2008
  29. S.K. Jung, S. Ragot, C. Lamblin, and S. Proust, "An embedded variable bit-rate coder based on GSM EFR: EFR-EV," Proc. ICASSP, Las Vegas, Nevada, USA, March-April 2008
  30. T.M.N. Hoang, M. Oger, S. Ragot, and M. Antonini, "Embedded transform coding of audio signals by model-based bit plane coding," Proc. ICASSP, Las Vegas, Nevada, USA, March-April 2008
  31. M. Oger, S. Ragot, and M. Antonini, "Model-based deadzone optimization for stack-run audio coding with uniform scalar quantization," Proc. ICASSP, Las Vegas, Nevada, USA, March-April 2008
  32. S. Ragot, B. Kövesi, R. Trilling, D. Virette, N. Duc, D. Massaloux, S. Proust, B. Geiser, M. Gartner, S. Schandl, H. Taddei, Y. Gao, E. Shlomot, H. Ehara, K. Yoshida, T. Vaillancourt, R. Salami, M.S. Lee, D.Y. Kim, "ITU-T G.729.1: An 8-32 kbit/s scalable coder interoperable with G.729 for wideband telephony and Voice over IP," Proc. ICASSP, Honolulu, Hawaii, USA, April 2007
  33. D. Massaloux, R. Trilling, C. Lamblin, S. Ragot, E. Ehara, M.S. Lee, D.Y. Kim, and B. Bessette, "An 8-12 kbit/s embedded CELP coder interoperable with ITU-T G.729 coder: first stage of the new G.729.1 standard," Proc. ICASSP, Honolulu, Hawaii, USA, April 2007
  34. M. Oger, S. Ragot, and M. Antonini, "Transform audio coding with arithmetic-coded scalar quantization and model-based bit allocation," Proc. ICASSP, Honolulu, Hawaii, USA, April 2007
  35. M. Oger, S. Ragot, and M. Antonini, "Low-complexity wideband LSF quantization by predictive KLT coding and generalized Gaussian modeling," Proc. EUSIPCO, Florence, Italia, Sept. 2006
  36. M. Oger, J. Bensa, S. Ragot, and M. Antonini, "Stack-run audio coding", AES 120th convention, Paris, France, May 2006
  37. S. Ragot, B. Kövesi, D.Virette, R. Trilling, and D. Massaloux, "A 8-32 kbit/s scalable wideband speech and audio coding candidate for ITU-T G729EV standardization," Proc. ICASSP, Toulouse, France, May 2006
  38. M. Oger, S. Ragot, and M. Antonini, "Model-based coding of LPC parameters for speech compression," Proc. CORESA, Rennes, France, Nov. 2005 (in French)
  39. M. Oger, S. Ragot, and R. Lefebvre, "Companded Lattice VQ for Efficient Parametric LPC Quantization," Proc. EUSIPCO, Vienna, Austria, Sept. 2004
  40. M. Oger, S. Ragot, and R. Lefebvre, "Wideband LPC Spectrum Envelope Coding Based on Gaussian Mixture Models and Companded Lattice VQ," Proc. 22nd Biennial Symposium on Communications, Kingston, ON, Canada, June 2004
  41. S. Ragot, B. Bessette, and R. Lefebvre, "Low-Complexity Multi-Rate Lattice Vector Quantization with Application to Wideband TCX Speech Coding at 32 kbit/s," Proc. ICASSP, Montreal, Canada, May 2004
  42. S. Ragot, H. Lahdili, and R. Lefebvre, "Wideband LSF Quantization by Generalized Voronoi Codes," Proc. Eurospeech, Aalborg, Danemark, Sept. 3-7, 2001
  43. S. Ragot, M. Xie, and R. Lefebvre, "Near-Ellipsoidal Lattice Quantization by Generalized Voronoi Coding," Proc. Canadian Workshop on Information Theory, Vancouver, BC, Canada, June 3-6, 2001
  44. V.T. Ruoppila and S. Ragot, "Index assignment for predictive wideband LSF quantization," Proc. IEEE Workshop on Speech Coding, Delevan, Wisconsin, USA, Sept. 17-20, 2000
  45. L. Tancerel, S. Ragot, V.T. Ruoppila, and R. Lefebvre, "Combined Speech and Audio Coding by Discrimination," Proc. IEEE Workshop on Speech Coding, Delevan, Wisconsin, USA, Sept. 17-20, 2000
  46. L. Tancerel, S. Ragot, and R. Lefebvre, "Speech/music discrimination for Universal Audio Coding," Proc. 20th Biennal Symposium on Communications, Queen's University, Kingston, Canada, May 28-31, 2000
  47. S. Ragot, R. Lefebvre, R. Salami, and J.-P. Adoul, "Stochastic-algebraic wideband LSF quantization," Proc. ICASSP, Istanbul, Turkey, June 5-9, 2000
  48. S. Ragot, J.-P. Adoul, R. Lefebvre, and R. Salami, "Low complexity LSF quantization for wideband speech coding," Proc. IEEE Workshop on Speech Coding, Haikko Manor, Porvoo, Finland, June 20-23, 1999
  49. S. Ragot, R. Salami, and R. Lefebvre, "Design of Test Sequences for G.729 Annex E," Proc. IEEE Workshop on Speech Coding, Haikko Manor, Porvoo, Finland, June 20-23, 1999

Theses

Granted Patents

  • Method and Device for Multirate Scalable Lattice Vector Quantization, US7106228
  • Methods and Devices for audio compression based on Acelp/Tcx coding and multi-rate lattice vector quantization, CA2457988
  • Hierarchical Encoding/Decoding Device, EP1905010
  • Method for Switching Rate– and Bandwidth–Scalable Audio Decoding Rate, EP1907812