What is an adaptive multi-life (AMR)?
Adaptive Multi-Rate (AMR) is used in speech coding and involves compression of audio data. Sound data compression allows more storage on voice files. ".amt" is a popular extension of the file name for AMR. Many mobile phones use AMR for speech storage.
AMR is particularly associated with a global mobile communication system (GSM). GSM, a system switched by a circuit, came in Europe at the age of 80 and is used in many European countries. Several cellular companies in the United States and other non -European countries also use GSM technology.
speech coding uses a codec of circuit speech or voice codec that digitally transforms speech. Music can be coded and decoded into a voice codec, but the quality of the music produced is usually quite bad. Speech or voice codec is specially made to analyze human language rather than offering quality sound in other sound forms such as music.
AMR used in cellular technology is said to provide the highest qualityITU Speery for remote mobile phone communication at the lowest possible cost. AMR is considered a very adaptable language code for many different radio channels. AMR can adapt by providing additional bits that help to correct errors when the channel conditions are bad, while still providing only a minimum amount of bits during good channel conditions. This quality means that AMR has multiple bits for speech coding than other speech codecs.
AMR is not the first voice codec used for GSM, but fourth. Improved code full of rates (EFR) and two other codecs of speech differ from AMR because they cannot adjust their speed produced. It is said that AMR offers the best quality of the voice of four codecs of speech. Mobile phone manufacturers continue to develop AMR Codec technology by striving for the most natural voice quality. These manufacturers often perform consumption tests for testThe brightest voice transmission on mobile phones.
Voice activity detection (VAD), generating noise of comfort (CNG) and discontinuous transmission (DTX) are some important features of AMR. VAD distinguishes speech from silence and helps processing speech and defects in AMR helps to improve speech coding quality. CNG is a low -level background static added intentionally to minimize some negative effects of silence, such as sudden swings at sound levels from voice to silence. DTX technology controls the transmitter switch during wireless conversations so that batteries or amplifiers are not unnecessarily used during quiet periods when there is no speech.