MPEG-4 SLS, or MPEG-4 Scalable to Lossless as per

ISO ISO is the most common abbreviation for the International Organization for Standardization. ISO or Iso may also refer to: Business and finance * Iso (supermarket), a chain of Danish supermarkets incorporated into the SuperBest chain in 2007 * Iso ...

IEC The International Electrotechnical Commission (IEC; in French: ''Commission électrotechnique internationale'') is an international standards organization that prepares and publishes international standards for all electrical, electronic and r ...

14496-3:2005/Amd 3:2006 (Scalable Lossless Coding), is an extension to the

MPEG-4 Part 3 MPEG-4 Part 3 or MPEG-4 Audio (formally ISO/IEC 14496-3) is the third part of the ISO/IEC MPEG-4 international standard developed by Moving Picture Experts Group. It specifies audio coding methods. The first version of ISO/IEC 14496-3 was publish ...

(

MPEG-4 MPEG-4 is a group of international standards for the compression of digital audio and visual data, multimedia systems, and file storage formats. It was originally introduced in late 1998 as a group of audio and video coding formats and related tec ...

Audio) standard to allow

lossless Lossless compression is a class of data compression that allows the original data to be perfectly reconstructed from the compressed data with no loss of information. Lossless compression is possible because most real-world data exhibits statistic ...

audio compression scalable to

lossy In information technology, lossy compression or irreversible compression is the class of data compression methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to reduce data size ...

MPEG-4 General Audio coding methods (e.g., variations of AAC). It was developed jointly by the Institute for Infocomm Research (I²R) and Fraunhofer, which commercializes its implementation of a limited subset of the standard under the name of HD-AAC. Standardization of the HD-AAC profile for MPEG-4 Audio is under development (as of September 2009). MPEG-4 SLS allows having both a

layer and a lossless correction layer similar to

Wavpack WavPack is a free and open-source lossless audio compression format and application implementing the format. It is unique in the way that it supports hybrid audio compression alongside normal compression which is similar to how FLAC works. I ...

Hybrid,

OptimFROG OptimFROG is a proprietary lossless audio data compression codec developed by Florin Ghido. OptimFROG is optimized for very high compression (small file sizes) at the expense of encoding and decoding speed, and consistently measures among the hi ...

DualStream and

DTS-HD Master Audio DTS-HD Master Audio (DTS-HD MA; known as DTS++ before 2004) is a multi-channel, lossless audio codec developed by DTS as an extension of the lossy DTS Coherent Acoustics codec (DTS CA; usually itself referred to as just DTS). Rather than being ...

, providing backwards compatibility to

MPEG The Moving Picture Experts Group (MPEG) is an alliance of working groups established jointly by International Organization for Standardization, ISO and International Electrotechnical Commission, IEC that sets standards for media coding, includ ...

AAC-compliant

bitstream A bitstream (or bit stream), also known as binary sequence, is a sequence of bits. A bytestream is a sequence of bytes. Typically, each byte is an 8-bit quantity, and so the term octet stream is sometimes used interchangeably. An octet may ...

s. MPEG-4 SLS can also work without a lossy layer (a.k.a. "SLS Non-Core"), in which case it will not be backwards compatible,

Lossy compression In information technology, lossy compression or irreversible compression is the class of data compression methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to reduce data size ...

of files is necessary for files that need to be streamed to the Internet or played in devices with limited storage. With

DRM DRM may refer to: Government, military and politics * Defense reform movement, U.S. campaign inspired by Col. John Boyd * Democratic Republic of Madagascar, a former socialist state (1975–1992) on Madagascar * Direction du renseignement milita ...

, ripping of the lossless data or playback on non

-enabled devices could be disabled. MPEG-4 SLS is not related in any way to

MPEG-4 ALS MPEG-4 Audio Lossless Coding, also known as MPEG-4 ALS, is an extension to the MPEG-4 Part 3 audio standard to allow lossless audio compression. The extension was finalized in December 2005 and published as ISO/IEC 14496-3:2005/Amd 2:2006 in 200 ...

(Audio Lossless Coding).

Background

Market demand for highly compressed,

audio compression technologies is slowly diminishing, as network and storage technologies continually improve their ability to deliver high-sampling-rate, high-resolution audio. New lossless audio coding technologies that need higher bandwidth and larger storage capacities may now be appropriate for many applications and have been gaining attention in recent years. In addressing this need,

issued a Call for Proposals (CfP) in October 2002 to solicit a technology that could address all these needs. The CfP requested proposals for a

and scalable technology that was backward compatible with the existing MPEG AAC

codec A codec is a device or computer program that encodes or decodes a data stream or signal. ''Codec'' is a portmanteau of coder/decoder. In electronic communications, an endec is a device that acts as both an encoder and a decoder on a signal or da ...

, and could operate efficiently at several different sampling rates and word length combinations. Institute for Infocomm Research
I2R
technologies were adopted for the scalable to lossless coding (14496-3/AMD5) architecture Reference Model 0. I2R offers a fully scalable to lossless audio coding solution. On top of the core AAC codec, a scalable extension layer increases the signal-to-noise ratio, reaching lossless quality at data rates comparable to those of current pure lossless audio codecs, that is, at average compression ratios of about 58%. The scalability of the extension makes this combination a coding solution for production environments, where the result is to be transmitted to several recipients through channels of differing

bandwidth Bandwidth commonly refers to: * Bandwidth (signal processing) or ''analog bandwidth'', ''frequency bandwidth'', or ''radio bandwidth'', a measure of the width of a frequency range * Bandwidth (computing), the rate of data transfer, bit rate or thr ...

. Furthermore, for private and professional use in music archives, this enables storing the original music data and transferring compressed copies (e.g. to portable devices) without transcoding.

Licensing

The Licensing Administrator for the MPEG-4 Audio

patent pool In patent law, a patent pool is a consortium of at least two companies agreeing to cross-license patents relating to a particular technology. The creation of a patent pool can save patentees and licensees time and money, and, in case of blocking ...

is Via Licensing Corporation. Licensors offering their SLS patents through the Via Licensing Corporation's licensing program include A*STAR Exploit Technologies Pte Ltd (Singapore), Fraunhofer IIS (Germany), and

Nippon Telegraph and Telephone , commonly known as NTT, is a Japanese telecommunications company headquartered in Tokyo, Japan. Ranked 55th in Fortune Global 500, ''Fortune'' Global 500, NTT is the fourth largest telecommunications company in the world in terms of revenue, as w ...

Corporation (Japan). The licensing fees varies - e.g. a licensee shall pay $0.098 to the Via Licensing Corporation for each copy of PC software decoder sold or supplied.

Releases

In 2011, Los Angeles based hip hop group People Under The Stairs released ''Highlighter'', the first commercial HD-AAC release taken directly from 24 to 48 session files, encoded and sold directly to fans via the websit
PL70.net
ref name="release info">

References

External links

International Organization for Standardization MPEG-4 SLS pageMPEG-4 SLS - MultimediaWikiA-Star press release
* ttps://archive.today/20081120230416/http://www.hd-aac.com/ HD-AAC.combr>Official MPEG web site
{{Compression formats MPEG-4 Open standards covered by patents

Background

Licensing

Releases

See also

References

External links