During the years 1999 and 2000, the Telecommunication Industry Association (TIA) and the 3 Generation Partnership Project 2 (3GPP2), managed a competition and a selection process for a new speech coding standard for CDMA applications. The new speech coding standard, which is coined Selectable Mode Vocoder (SMV), will become a service option in CDMA systems such as IS-95 and cdma2000, providing ...

Considerable research attention has been directed towards speech and audio coding algorithms capable of producing high quality coded speech and audio, however few of these use signal representations which account for temporal as well as spectral detail. This paper presents a new technique for 16 kHz wideband speech and audio coding, whereby analysis and synthesis are performed using a linear ph...

This paper describes a hybrid sub-band speech coding scheme based on sinusoidal coding and CELP. Purely voiced speech is encoded using sinusoidal coding techniques and phase information is selectively transmitted. For mixed and unvoiced speech, the lower band is processed by sinusoidal coding algorithms while the upper band is encoded using CELP. To accommodate the extra bandwidth required by t...

In medium to low bit rate speech codecs the speech signal is represented by a set of parameters. The most important concept is presently Code Excited Linear Predictive (CELP) coding. A speech segment of typically 10 to 20ms is described in terms of prediction coefficients, gain factors and excitation vectors. Due to the high compression rates (0.5-1.5 bits per speech sample) the parameters are ...

This thesis deals with developing improved techniques for speech coding based on the recent developments in sparse signal representation. In particular, this work is motivated by the need to address some of the limitations of the wellknown linear prediction (LP) model currently applied in many modern speech coders. In the first part of the thesis, we provide an overview of Sparse Linear Predict...

Prototype waveform interpolation is one of the most e cient compression techniques for coding the speech signal at bit rates below 4 kb/s. Most of the PWI coders employ prototype waveforms of the linear predictive residual signal for coding purpose. In the latest PWI systems, decomposition methods are used to separate the voiced and unvoiced components of the prototype waveforms prior to coding...

This study aimed to investigate the speech perception and subjective preference of unilaterally deafened cochlear implant users for two different speech coding strategies. Thirteen subjects who received a cochlear implant were provided with 2 maps that differed in the speech coding strategy, FS4 or FS4-p (MED-EL). Subjects were requested to alternate between the two maps daily for two weeks and...

Problem statement: The flexible bit-rate speech coder plays an important role in the modern speech communication. The MP-CELP speech coder which is a candidate of the MPEG4 natural speech coder supports a flexible and wide bit-rate range. However, a fine scalability had not been included. To support finer scalability of the coding rate, it had been studied in this study. Approach: In this study...

Speech coding has been major issue within the space of digital speech process. It unfeasible to access unlimited bandwidth of a channel when we tend to send a signal across it that results in code and compress speech signals. Speech compression is needed within the areas of long distance communication, high-quality speech storage, and message coding. For instance in digital cellular technology ...

Problem statement: The studies on Thai expressive speech or emotional speech have been conducted for years. Most of them are expected to analysis the characteristics of Thai expressive speech. However, the conclusive reviews on these studies have not been conducted for further study on the speech technology or application of Thai expressive speech. Approach: The review of research on Thai expre...