Advanced Audio Coding (AAC) is an audio compression technology initially introduced with MPEG-2. It’s also referred to as MPEG-2 Part 7 and is the technological successor to the well-known MP3 format, or MPEG-1/2 Layer-3. AAC supports up to 48 primary audio channels with sampling rates ranging from 8 kHz to 96 kHz. Additionally, it can handle 16 low-frequency effect channels, 16 channels for overdubs or multiple languages, and 16 separate data streams. The capabilities of MPEG-2 AAC have been further enhanced in its MPEG-4 AAC iteration.

AAC provides different encoding methods (also called Profiles in MPEG-2 or Object Types in MPEG-4), some versions are: MPEG-2 AAC Main, MPEG-2 AAC LC (Low Complexity), MPEG-2 AAC , SSR (Scalable Sampling Rate), MPEG-4 AAC Main, MPEG-4 AAC LC (Low Complexity), MPEG-4 AAC SSR (Scalable Sampling Rate), MPEG-4 AAC HE (High Efficiency), MPEG-4 AAC LD (Low Delay), MPEG-4 AAC LTP (Long Term Prediction)