Vector sum excited linear prediction
- Vector sum excited linear prediction
Vector sum excited linear prediction (VSELP) is a speech coding method used in the IS-54 standard. This codec was used in early TDMA cell phones in the United States. It was also used in the first version of RealAudio for audio over the Internet. The IS-54 VSELP standard was published by the Telecommunications Industry Association in 1989.
IS-54 VSELP specifies an encoding of each 20 ms of speech into 159-bit frames, thus achieving a raw data rate of 7.95 kbit/s. In an actual TDMA cell phone, the vocoder output is packaged with error correction and signaling information, resulting in an over-the-air data rate of 16.2 kbit/s. For internet audio, each 159-bit frame is stored in 20 bytes, leaving 1 bit unused. The resulting file thus has a data rate of exactly 8 kbit/s.
A major drawback of VSELP is its limited ability to encode non-speech sounds, so that it performs poorly when encoding speech in the presence of background noise. For this reason, use of VSELP has been gradually phased out in favor of newer codecs.
VSELP is also the encoding method used in some early Motorola Type II trunking systems. It was phased out in favor of the newer IMBE method.
External links
* [http://www.tiaonline.org/ Telecommunications Industry Association web site]
References
* Ira A. Gerson and Mark A. Jasiuk, "Vector Sum Excited Linear Prediction (VSELP)," IEEE Workshop on Speech Coding for Telecommunications, September 1989, pp. 66–68
* Ira A. Gerson and Mark A. Jasiuk, "Vector sum excited linear prediction (VSELP) speech coding at 8 kbps," Proceedings of the 1990 IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP-90), April 1990, pp. 461-464
Wikimedia Foundation.
2010.
Look at other dictionaries:
Code-excited linear prediction — (CELP) is a speech coding algorithm originally proposed by M.R. Schroeder and B.S. Atal in 1985. At the time, it provided significantly better quality than existing low bit rate algorithms, such as residual excited linear prediction and linear… … Wikipedia
VSELF — Vector Sum Excited Linear Prediction … Acronyms
VSELF — Vector Sum Excited Linear Prediction … Acronyms von A bis Z
List of codecs — The following is a list of codecs. Audio codecs Non compression formats * Audio Interchange File Format (AIFF, container format) * Resource Interchange File Format (RIFF, container format) * WAV – Microsoft WAVE format (format supports… … Wikipedia
Audioformat — Ein Audioformat ist ein Datenformat, das den Aufbau einer Audiodatei oder eines Audiodatenstromes beschreibt. Inhaltsverzeichnis 1 Allgemein 2 Datenreduktion oder Datenkompression 3 Liste gängiger Audioformate … Deutsch Wikipedia
Digital AMPS — IS 54 and IS 136 are second generation (2G) mobile phone systems, known as Digital AMPS (D AMPS). It was once prevalent throughout the Americas, particularly in the United States and Canada. D AMPS is considered end of life, and existing networks … Wikipedia
Digital AMPS — Esta página o sección está siendo traducida del idioma inglés a partir del artículo Digital AMPS, razón por la cual puede haber lagunas de contenidos, errores sintácticos o escritos sin traducir. Puedes colaborar con Wikipedia continuando… … Wikipedia Español
линейное предсказание с возбуждением векторной суммой — — [Л.Г.Суменко. Англо русский словарь по информационным технологиям. М.: ГП ЦНИИС, 2003.] Тематики информационные технологии в целом EN vector sum excited linear predictionVSELP … Справочник технического переводчика
линейное предсказание с возбуждением по векторной сумме — Речевой кодер, реализованный компанией Motorola в 1994 г. на основе метода “анализ через синтез”. Входной сигнал нарезается на сегменты по 160 выборок (20 мс) и для каждой из них определяются параметры сигнала возбуждения. Такой… … Справочник технического переводчика
линейное предсказание с инициацией векторной суммой — (МСЭ R F.757 3). [http://www.iks media.ru/glossary/index.html?glossid=2400324] Тематики электросвязь, основные понятия EN vector sum excited linear predictionVSELP … Справочник технического переводчика
