Wikipedia

LAME

This article is about the computer program. For other uses, seeLame (disambiguation).

LAMEis a softwareencoderthat converts digital audio into theMP3 audio coding format.LAME is afree softwareproject that was first released in 1998 and has incorporated many improvements since then, including an improvedpsychoacousticmodel. The LAME encoder outperforms early encoders likeL3enc[3]and possibly the "gold standard encoder" MP3enc, both marketed by Fraunhofer.[4]

LAME
Developer(s)LAME Developers
Initial release1998;26 years ago(1998)
Stable release
3.100[1] / 13 October 2017;7 years ago(13 October 2017)
Repositorysourceforge.net/p/lame/svn/HEAD/tree/
Operating systemCross-platform
TypeCodec
LicenseGNU Lesser General Public License[2]
Websitelame.sourceforge.io

LAME was required by some programs released as free software in which LAME was linked for MP3 support. This avoided including LAME itself, which used patented techniques, and so required patent licenses in some countries. All relevant patents have since expired, and LAME is now bundled withAudacity.[5]

History

edit

The nameLAMEis arecursive acronymfor "LAME Ain't an MP3 Encoder".[6]

Around mid-1998, Mike Cheng created LAME 1.0 as a set of modifications against the 8Hz-MP3 encoder source code. After some quality concerns were raised by others, he decided to start again from scratch based on the dist10 MPEG reference software sources. His goal was only to speed up the dist10 sources, and leave its quality untouched. That branch (a patch against the reference sources) became Lame 2.0. The project quickly became a team project. Mike Cheng eventually left leadership and started working ontooLAME(an MP2 encoder).[7]

Mark Taylor then started pursuing increased quality in addition to better speed, and released version 3.0 featuring gpsycho, a newpsychoacoustic modelhe developed. A few key improvements since LAME 3.x, in chronological order:[7]

  • May 1999 (LAME 3.0): a new psychoacoustic model (GPSYCHO) is released.
  • June 1999 (LAME 3.11): The firstvariable bitrate(VBR) implementation is released. Soon after this, LAME also became able to target lower sampling frequencies from MPEG-2. (LAME 3.99 also supports the technologically simpleraverage bitrate(ABR), but it is unclear whether it was added before or with VBR.)
  • November 1999 (LAME 3.52): LAME switches from a GPL license to an LGPL license, which allows using it with closed-source applications.
  • May 2000 (LAME 3.81): the last pieces of the original ISO demonstration code are removed. LAME is not a patch anymore, but a full encoder.
  • December 2003 (LAME 3.94): substantial improvement to default settings, along with improved speed. LAME no longer requires users to enter complicated parameters to produce good results.
  • May 2007 (LAME 3.98): default variable bitrate encoding speed is vastly improved.
edit

Like all MP3 encoders, LAME implemented techniques covered bypatentsowned by theFraunhofer Societyand others. The developers of LAME did not license the technology described by these patents. Distributing compiled binaries of LAME, its libraries, or programs that derive from LAME in countries where those patents have been granted may have constitutedinfringement,but since 23 April 2017, all of these patents have expired.[8][9]

The LAME developers stated that, since their code was only released in source code form, it should only be considered as an educational description of an MP3 encoder, and thus did not infringe any patent in itself. They also advised users to obtain relevant patent licenses before including a compiled version of the encoder in a product.[10]Some software was released using this strategy: companies used the LAME library, but obtained patent licenses.

In the course of the 2005Sony BMG copy protection rootkit scandal,there were reports that theExtended Copy Protectionrootkitincluded on someSonycompact discshad portions of the LAME library without complying with the terms of theLGPL.[11][12][13]

See also

edit

References

edit
  1. ^"History".Archived fromthe originalon 15 October 2017.Retrieved15 October2017.
  2. ^"CVS Info for project lame".
  3. ^"Opus FAQ".This is what made it possible for modern MP3 encoders (e.g. LAME) to improve far beyond the original L3enc and dist10 reference implementations.
  4. ^"LAME MP3 Encoder:: Related Links".LAME Team.Retrieved19 March2013.
  5. ^Lendino, Jamie (27 September 2019),"Audacity Review",PC Magazine
  6. ^"LAME MP3 Encoder:: About".Lame.sourceforge.net.Retrieved17 March2012.
  7. ^ab"LAME Changelog".svn.code.sf.net.
  8. ^"mp3".Fraunhofer IIS.Retrieved2 May2017.
  9. ^"Alive and Kicking: MP3 software, patents and licenses (Fraunhofer Audio Blog)".Fraunhofer Audio Blog.Fraunhofer IIS. 18 May 2017.Retrieved19 May2017.The licensing program coming to an end is due to the fact that the last patent included in the program expired.The page's later caution about third-party implementation–specific patents is not about LAME's implementation.[citation needed]
  10. ^Taylor, Mark (June 2000)."LAME Technical FAQ".Archived fromthe originalon 8 February 2012.Retrieved21 February2008.
  11. ^"Sony BMG Software May Contain Open-Source Code".Fox News.Reuters. 21 November 2005.Retrieved26 November2011.
  12. ^"Is Sony in violation of the LGPL?".The-interweb. Archived fromthe originalon 24 January 2009.Retrieved17 March2012.
  13. ^"Sony's XCP DRM".Archived fromthe originalon 24 November 2005.
edit
Retrieved from "https://en.wikipedia.org/w/index.php?title=LAME&oldid=1256462843"