Main Research Areas:
  • Speech coding: Lossless wideband CELP coding, harmonic-plus-noise coding, quality enhancement of CELP-coded speech
  • Speech synthesis: H+N acoustic modelling, V/UV mixing, articulatory modelling, low-cost synthesizer architecture
  • Speech enhancement: Narrowband to wideband quality enhancement of telephone speech
  • Audio coding: perceptual coding, non-linear modelling, lossless multi-channel audio coding
  • Fast algorithms: computation of LSP, Voltera filter design, thin lattice filter design
  • Signal processor architecture: scalable architecture for speech processing
  • 3D Audio Sound Processing: HRTF and source localization

 
Current Research Projects
  1. Speech Morphism via Tracking of Speech Dynamics
  2. Lossless Audio Coding using Predictive Multitone N+N Model with Closed-Loop Optimized Entropy Coding
  3. Synthesis of High-Quality Speech Using Harmonic-plus-Noise Model
  4. Quality Enhancements of Coded Speech for Digital Cellular Communications
  5. Object-Based Coding of Natural and Man-Made Sounds

  6. Binaural Playback of 3D Spatial Audio Using Interpolative Head Related Transfer Function with Azimuth Feedback Control for Portable Applications

  7. Car Noise Suppression using Analysis-by-Synthesis Approach via Harmonic-plus-Noise Modelling

 
Sampled Publications
  1. C.-F. Chan, ˇ§Efficient Implementation of Perceptual Postfilter for CELP Coding of Speech,ˇ¨ IEE Electronics Letters, Vol. 38, No. 24, pp1604-1605, November 2002.
  2. C. F. Chan, "Efficient Implementation of Class of Isotropic Quadratic Filters Using Walsh-Hadamard Transform," IEE Electronics Letters, pp.1306-1308, Vol.35 No.16, 1999.
  3. Eric Y.M. Yu and C.F. Chan, "Variable Bit Rate Mbelp Speech Coding via V/UV Distribution Dependent Spectral Quantization," IEEE int. Conf. on Acoustics, Speech and Signal Processing, pp.1607-1610, Phoenix, USA 1999.
  4. Eric W.M. Yu and C. F. Chan, "A Variable-Rate Harmonic Speech Coder with Efficient Spectral Quantization," IEEE int. Symposium on Circuits and Systems, Vol. III, pp.114-117. Orlando, USA, May 1999.
  5. C. F. Chan and W. K. Hui, "Quality Enhancement of Narrowband CELP-Coded Speech Via Wideband Harmonic Re-Synthesis," IEEE int. Conf. on Acoustics, Speech and Signal Processing, pp.1187-1190, Germany, May 1997.
  6. C. F. Chan, "Combined Speech and Audio Coding using Non-Linear Adaptations," IEEE Workshop on Speech Coding, Pennsylvania, USA, Sept. 1997.
  7. C. F. Chan and Alexander Teng, "ASIC Implementation of a High-Quality Speech Coding Algorithm at 16 kbps," Int. Conf. on Signal Processing Applications & Technology, pp. 1644-1647. San Diego, USA, Sept. 1997.
  8. C. F. Chan, T. C. Pang and C. K. Chan, "Scaleable Speech Processor (SSP): An ASIC DSP for Low-End Consumer Products," Int. Conf. on Signal Processing Applications & Technology, pp.213-216, San Diego, USA, Sept. 1997.
  9. C. F. Chan and M. T. Chu, "Wideband Coding of Speech Using Neural Network Gain Adaptation," European Conference on Speech Communication and Technology, pp. 1507-1510, Greece, Sept. 1997.
  10. Eric W. M.  Yu and C. F. Chan, "Variable Rate MBELP Speech Coding V/UV Distribution Dependent Spectral Quantization," IEEE int. Conf. on Acoustics, Speech and Signal Processing, pp.1607-1610, Germany, May 1997.
  11. C. F. Chan and W.M.E. Yu, "Efficient Frequency-Domain Postfiltering for Multiband Excited Linear Predictive Coding of Speech," IEE Electronics Letters, pp.1061-1063, June 1996.
  12. C. F. Chan and W.M.E. Yu, "Improving Pitch Estimation for Efficient Multiband Excitation Coding of Speech," IEE Electronics Letters, pp.870-872, May 1996.
  13. C. F. Chan, "Fast Stochastics Codebook Search Through the Use of Odd-Symmetric Crosscorrelation Basis Vectors," IEEE int. Conf. on Acoustics, Speech and Signal Processing, pp.21-24, Detroit, USA, May, 1995..
  14. C. F. Chan and S. P. Chiu, "Efficient Codebook Search Procedure for Vector Sum Excited Linear Predictive Coding of Speech," IEE Electronics Letters, pp.1830-1831, October 1994.
  15. K. W. Law and C. F. Chan, "Split-Dimension Vector Quantization of PARCOR Coefficients for Low Bit Rate Speech Coding," IEEE Trans. on Speech and Audio Processing, pp.443-446, July 1994.
  16. K. W. Law, and C. F. Chan, "A Trellis In-Loop PARCOR Coefficients Quantizer for Speech Signals," IEE Proceeding in Communication, Speech, and Vision, Vol. 140, No. 5, pp.321-326, Oct. 1993.
  17. K. W. Law, W. F. Leung and C. F. Chan, "Reducing the Complexity and Storage of CELP Speech Coding Using Self-orthogonal Codebook," IEE Electronics Letters, Vol. 29, No. 10, pp.928-930, March 1993.
  18. C. F. Chan, and K. W. Law "A New Multi-Stage Scheme for Vector Quantisation of PARCOR Coefficients," IEE Electronics Letters, Vol. 28, No. 13, pp.1267-1268, June 1992.
  19. C. F. Chan, "A Dynamic Programming Algorithm for Linear Prediction Using Thinned Lattice Filter," IEE Electronics Letters, Vol. 28, No. 1, pp.91-92, Jan. 1992.
  20. C. F. Chan and K. W. Law, "In-Loop Quantization of Reflection Coefficients", IEE Electronics Letters, Vol. 27, No. 22, pp.2015-2016, Oct. 1991.
  21. C. F. Chan, "Computation of LSP Parameters from Reflection Coefficients," IEE Electronics Letters, Vol. 27, No. 19, pp.1773-1774, Sept. 1991.