What is the different between the AAC and GSM/AMR?
Advanced Audio Coding (AAC) is an audio compression standard that has evolved from MPEG2 – Layer 3 (MP3). AAC improves upon MP3 by using better filtering methods, noise shaping and quantization resolution to produce higher quality audio files at lower bit rates. AAC is designed for use within digital broadcasting systems. With its ability to support sample rates from 8-128 KHz, it is the future of audio in multimedia. GSM/AMR is an audio standard widely used for audio in GPRS and W-CDMA networks. The Global System for Mobile (GSM) Adaptive Multi-Rate (AMR) voice coder is defined in the ETSI GSM 06.90 specification. The Adaptive Multi Rate (AMR) speech codec is the default speech codec for GSM 2+ and WCDMA third generation wireless systems. GSM-AMR is based on Algebraic CELP (ACELP) and operates at eight bit rates ranging from 4.75 Kbps to 12.2 Kbps. It is developed to preserve high speech quality under a wide range of transmission conditions. The AMR codec is designed with a voice acti
