Real-time implementation and evaluation of variable rate CELP coders
Luis A. Hernández Gómez, Francisco Javier Casajus-Quiros, Carmén García Mateo, Javier Ortega-García · 1991
The authors describe the main topics related to a real-time implementation of the Proposed Federal Standard 1016 (PFS-1016) 4800 bps CELP (code excited linear prediction) voice coder together with some alternatives to extend real-time CELP schemes over a wide range of bit rates (8000, 6500, and 2400 bps are considered). Several procedures are evaluated in order to select the options in PFS-1016 that provide the highest quality for an implementation based on a single AT&T DSP32C chip. From the basic CELP scheme, higher and lower bit rates are derived after evaluation of the efficiency obtained for the different elements in this speech coding algorithm.>