An efficient low-bit rate CELP speech coding algorithm

  • Authors

    • A Satyanarayana Murthy
    • A Harika
    • Ch Nikhita
    https://doi.org/10.14419/ijet.v7i3.29.19318
  • Linear Prediction, Code-Exited Linear Prediction, Speech Coding, Bit-Rate.

  • Voice communication is one of the easiest and natural methods of communication between human beings. In recent times it became popular because of mobile communications. It contains information as well as personal information such as age, identity, emotions etc. The requirement for efficient coding method is still a research topic for noise environment. Speech coding technique reduces the bandwidth requirements and storage space for speech data. Efficient coding method helps to reduce the bit rate and at the same time keep the speech quality and intelligibility at reasonable rate. Many speech coders have been developed to compress effectively and to ensure optimized performance to the human ear. Service providers of mobile phone communications are looking for low bit rate coders to allocate more number of users in limited bandwidth. In this paper a mixed coding method i.e. Code Exited Linear Prediction (CELP) is implemented on noise free speech signals using MATLAB. With this more exact modeling of spectral zeros is possible compared to the linear predictive coding (LPC). Subjective tests indicated that the coder at 16kbps and 9.6kbps achieves a significant improvement in performance over LPC coder under the same coding framework and bit allocation.

     

     

  • References

    1. [1] Ian Mcloughlin, Applied speech and Audio Processing, Cambridge University Press.

      [2] B.S. Ttal and Suzanne and L.Hanauer, “Speech Analysis and Synthesis by Linear Prediction of the Speech waveâ€, Bell Laboratories, New Jersey, 1971.

      [3] Manfred R. Schroeder and Bishu S. Atal, “Code-exited linear prediction: High quality speech at low bit rates, AT&B Bell Laboratories, New Jercy.

      [4] Klaus Fell Baum, Jorg Pichter, “Human speech production based on linear predictive vocoder, April, 1999.

      [5] Digital Processing of Speech Signal by L.R.Rabiner and R.W. Schafer, Printice Hall, 1978.

      [6] Florian Keiler, Daniel Arfib and Udo Zolzer, “Efficient Linear Prediction for Digital Audio Effects†Germany.

      [7] Jani Nurminen, Victor Papa, “A Parametric Approach for Voice Conversionâ€, Nokia Research Centre, Finland.

      [8] Hwai-Tsuhu and Hss-Tsungwu, “A glottal- exited linear prediction model for low-bit – rate speech codingâ€.

      [9] Rhutuja Jage, Savitha Upadhya, “CELP and MELP speech coding techniquesâ€, International conference on wireless communications, signal processing and networking (WISPNET), 23-25, March 2016, Chennai, India.

      [10] Theory Dutoit and Ferran Marquees, Applied Signal Processing. A Matlab based proof of concepts.

      [11] Mahmoud A osman, Hussein M. Magboub Nasser, SA Alfandi, “Speech compression by LPC and Wavletâ€, 2nd International Conference in computer engineering and technology†(ICCET), 16-18, April 2010, Chengdu, China.

      [12] Takehir, Moriya, “Progress in LPC-based frequency domain audio codingâ€, Communication Laboratoriesâ€, NTT, Atsugi, Japan, April 2016

      [13] Kassim, Gunawan, “Development of low bit rate speech coder based on vector quantization and compressive sendingâ€, Journal of Applied Sciences, vol. 13, 49-59, 2013.

  • Downloads

  • How to Cite

    Satyanarayana Murthy, A., Harika, A., & Nikhita, C. (2018). An efficient low-bit rate CELP speech coding algorithm. International Journal of Engineering & Technology, 7(3.29), 586-590. https://doi.org/10.14419/ijet.v7i3.29.19318