3 MPEG-2 / MPEG-4 Audio
Advanced Audio Coding (AAC) is a standardized, lossy compression and encoding scheme for digital audio. It is specified both as Part 7 of the MPEG-2 standard, and Part 3 of the MPEG-4 standard. As such, it can be referred to as MPEG-2 Part 7 and MPEG-4 Part 3 depending on its implementation. However it is most often referred to as MPEG-4 AAC, or AAC for short .
MPEG-2 and MPEG-4 Audio (AAC) patents are licensed by Via Licensing Corporation. Please visit http://www.vialicensing.com for more information. Various patents from different companies or institutions are covered by these licenses but still others do claim to have relevant patents that are needed (e.g. Thomson states that it has relevant patents that are not included ). Via offers any company to submit their patent that covers a relevant part of a technology for an evaluation. If the patent meets the requirements it can be added to the patent pool at no further costs for the licensees. It is
No licenses or payments are required to be able to stream or distribute content in AAC format. This reason alone makes AAC a much more attractive format to distribute content than MP3, particularly for streaming content (such as Internet radio).
However, a patent license is needed by manufacturers or developers of end user encoder and/or decoder products. Under this category fall, according to Via licensing, all end-user products, when sold directly or through distribution to end users. Licensee's products that are not end user products are not covered by the license and would require that the party incorporating such a component or implementation into its end user product obtain its own license.
3.1 MPEG-2 AAC License
The royalties for a license of the MPEG-2 AAC pool are related to the number of units per year and decoder/encoder channels. A channel refers to an audio output channel. For example stereo is a two-channel implementation (left and right), while a surround sound system might have five or more audio channels. Special licensing prices for cellular phones, PC software are also available upon request. Table 3-1 shows an excerpt of standard royalties for MPEG-2 AAC.
Table 3-1. MPEG-2 AAC license royalties excerpt
3.2 MPEG-4 AAC License
The royalties for a license of the MPEG-4 AAC pool are, just like the MPEG-2 version, related to the number of units per year and decoder/encoder channels. Table 3-2 shows an excerpt of standard royalties for MPEG-4 AAC. For special licensing prices that apply for cellular phones or PC software please contact Via licensing.
Table 3-2. MPEG-4 AAC license royalties excerpt
 Information about various video/audio formats: http://www.wikipedia.org
 MP3 licensing from Thomson: http://www.mp3licensing.com
 Atmel as MP3 licensee: http://www.mp3licensing.com/licensees/index.asp
 MPEG-2 MPEG-4 Audio (AAC) licensing: http://www.vialicensing.com
 Windows Media licensing:
 Windows Media licensing fees and royalties: http://www.microsoft.com/windows/windowsmedia/licensing/licensing.aspx
 Atmel contact email: firstname.lastname@example.org
 Sisvel (Audio MPEG) MP3 licensing: http://www.audiompeg.com