List+of+Audio+Formats

MPEG-1 Audo Layer 3
Known to most as the MP3 file. MP3s can contain up to 2 channels of sound. They can be encoded at different bitrates: 64 kbps, 128 kbps, 192 kbps, and a variety of others from 32 to 320. Higher bitrates mean larger file sizes and better quality audio, although the ratio of audio quality to bitrate is not linear. (128 kbs sounds more than twice as good as 64 kbs, but 256 kbs doesn’t sound twice as good as 128 kbs.) Furthermore, the MP3 format allows for variable bitrate encoding, which means that some parts of the encoded stream are compressed more than others. For example, silence between notes can be encoded at a very low bitrate, then the bitrate can spike up a moment later when multiple instruments start playing a complex chord. MP3s can also be encoded with a constant bitrate, which, unsurprisingly, is called constant bitrate encoding.

Advanced Audio Coding
known as “AAC.” Standardized in 1997, gained prominence when Apple chose it as their default format for the iTunes Store. Originally, all AAC files “bought” from the iTunes Store were encrypted with Apple’s proprietary DRM scheme, called FairPlay. Many songs in the iTunes Store are now available as unprotected AAC files, which Apple calls “iTunes Plus” because it sounds so much better than calling everything else “iTunes Minus.” AAC was designed to provide better sound quality than MP3 at the same bitrate, and it can encode audio at any bitrate. (MP3 is limited to a fixed number of bitrates, with an upper bound of 320 kbs.) AAC can encode up to 48 channels of sound, although in practice no one does that. The AAC format also differs from MP3 in defining multiple profiles, in much the same way as H.264, and for the same reasons. The “low-complexity” profile is designed to be playable in real-time on devices with limited CPU power, while higher profiles offer better sound quality at the same bitrate at the expense of slower encoding and decoding.

known as “WMA.” As you might guess from the name, Windows Media Audio was developed by Microsoft. The acronym “WMA” has historically referred to many different things: a lossless audio codec (“WMA Lossless”), a speech-optimized codec (“WMA Voice”), and several different audio codecs (“WMA 1″, “WMA 2″, “WMA 7″, “WMA 8″, “WMA 9″, and “WMA Pro”). It is also (incorrectly) used to refer to the Advanced Systems Format, because WMA-encoded audio streams are usually embedded in an ASF container. Roughly speaking, the audio codecs (WMA 1-9) compete with MP3 and low-complexity AAC; WMA Lossless competes with Apple Lossless and FLAC; WMA Pro competes with high-complexity AAC, Vorbis, AC-3, and DTS. All the different codecs under the “WMA” brand are playable with Windows Media Player, which comes pre-installed on desktops and laptops running Microsoft Windows XP and Vista. WMA 1-9 support up to 2 channels of sound; WMA Pro supports up to 8 channels of sound.
 * Windows Media Audio **

known to many as “Ogg Vorbis,” Technically, “Ogg” is a container format, and Vorbis audio streams can be embedded in other containers. Vorbis audio streams are usually embedded in an Ogg container, but they can also be embedded in an MP4 or MKV container (or, with some hacking, [|i]n AVI). There are open source Vorbis encoders and decoders, including Oggconvert(encoder),ffmpeg(decoder), aotuv (encoder), and libvorbis (decoder). There are also QuickTime components for Mac OS X and DirectShow filters for Windows. Libvorbis supports an arbitrary number of sound channels.
 * Vorbis **

** Dobly Digital **
known as “AC-3.” AC-3 was developed by Dobly Laboratories. AC-3 is most well-known for being a mandatory format in the DVD standard; all DVD players must be able to decode AC-3 audio streams. It is also mandatory for Blu-Ray players, and many digital TV broadcasts send AC-3 audio streams as well. AC-3 supports up to 6 channels of soundand bitrates of up to 640 kbps, although its most popular application — audio on DVDs — is officially limited to 448 kbps. (Blu-Ray discs may use the maximum 640 kbps.) There are open source encoders and decoders for AC-3, including liba52 (decoding), AC3Filter (decoding), and Aften (encoding). ffmpeg has a compile-time option to include liba52, which will allow all ffmpeg-based players and plugin chains (like GStreamer) to play AC-3 audio streams. AC-3 is rarely seen in standalone audio files; it is designed to be embedded in a video container. Other than DVDs and Blu-Ray discs (which use a video container format I haven’t talked about yet), you can embed AC-3 audio streams in MKV, AVI, and — just standardized earlier this year —in MP4 Files.

…a.k.a. “DTS.” As you might guess from the name, DTS is designed for real-life movie theaters. Like WMA, “DTS” is a brand name for a family of different audio formats. The “core” DTS format supports up to six channels; later extensions like DTS-HD supportup to eight channels. There is also DTS HD Audio Master, a lossless variant by the same company. Core DTS is designed for high bitrates (up to 1536 kbps, which is virtually indistinguishable from being there in the first place). DTS-HD Master Audio bitrates can go even higher. Core DTS was not originally part of the DVD specification, so early DVD players did not support it. Most recent DVD players support natively decoding core DTS audio or passing the audio stream through to an external speaker system which decodes it, but relatively few DVDs include a DTS stream due to size constraints. Core DTS is a mandatory part of the Blu-Ray specification, and many Blu-Ray discs include a DTS audio track — sometimes the exact same stream that was originally played in the movie theater.
 * Digital Theater System**

Source: A gentle introduction to video encoding by Mark Pilgrim