Lossy compression is designed to reduce significantly the amount of data required to represent the audio recording and still sound like a faithful reproduction of the original uncompressed audio. Sampling frequency 8 kHz/13-bit (160 samples for 20 ms frames), filtered to 200-3400 Hz. It is a common audio format for consumer audio streaming or storage and a de facto standard of digital audio compression for the transfer and playback of music on most digital audio players.ĪMR speech codec consists of a multi-rate narrowband speech codec that encodes narrowband (200-3400 Hz) signals at variable bit rates ranging from 4.75 to 12.2 kbit/s with toll quality speech starting at 7.4 kbit/s. MPEG-1 or MPEG-2 Audio Layer III, more commonly referred to as MP3, is an audio coding format for digital audio that uses lossy data compression. AMR was adopted as the standard speech codec by 3GPP in October 1999 and is now widely used in GSM and UMTS.
The Adaptive Multi-Rate (AMR or AMR-NB or GSM-AMR) audio codec is an audio compression format optimized for speech coding.
