Mobile File Format, aac-lc

3GP is a simplified version of the MPEG-4 Part 14 (MP4) container format, designed to decrease storage and bandwidth requirements in order to accommodate mobile phones. It stores video streams as MPEG-4 Part 2 or H.263 or MPEG-4 Part 10 (AVC/H.264), and audio streams as AMR-NB, AMR-WB, AMR-WB+ or AAC-LC. A 3GP file is always big-endian, storing and transferring the most significant bytes first. It also contains descriptions of image sizes and bitrate. There are two different standards for this format:

3GPP (for GSM Based Phones, may have filename extension .3gp)
3GPP2 (for CDMA Based Phones, may have filename extension .3g2)

AAC LC

Overview

MPEG-2/MPEG-4 Low Complexity Audio Codec (AAC-LC) is the simplest and most widely used and supported AAC profile. Despite its low computational complexity, AAC LC provides good sound quality at as low as 64 Kbps bitrate. Codec supports various sampling rates and bitrates. These features have made AAC LC codec a perfect solution for a wide range of application.

Features

Fully compliant to the ISO MPEG-2/MPEG-4 Low Complexity codec standard
Low CPU usage and memory footprint
Sampling rates from 8 to 96 kHz (compared to 48 kHz for MP3)
Bit rates from 8 Kbps to 256 Kbps;
Support for mono and stereo channels
TI C6xx version is XDAIS compliant (including parent/child support for paging tables)
Code is reentrant, supports multithreading and dynamic memory allocation

Benefits

Highly optimized code ideal for resource constrained applications
Easy integration and fast time to market
Allows to save several hours of SoC battery life