Xvid

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Xvid

Xvid logo.svg
Basic data

developer Xvid
Current  version 1.3.7
(December 28, 2019)
operating system Windows , macOS , Linux
programming language C , assembly language
category MPEG-4 - video codec
License GNU General Public License, version 2
www.xvid.com

Xvid is a free implementation of the MPEG-4 - Video codecs originally on the OpenDivX - source -based. The underlying source code of OpenDivX came from the MPEG-4 reference implementation of the EU project MoMuSys . The Xvid project was started by several volunteer programmers after the OpenDivX source code was closed. The name of the project is an anagram of the name DivX . With the unencrypted source code published by OpenDivX, the programmers were given the opportunity to change and optimize the basic properties of the codec.

Due to patent problems, no official compiled versions of the source code are provided by the Xvid team. Commercial distribution of Xvid is possible as long as the GPL conditions are carefully observed. In some countries such as the USA or Japan , additional fees apply for the patents listed above.

From version 1.1.3 of June 29, 2007 the MPEG-4 Part 2: Visual Advanced Simple Profile is supported. This means that Xvid enables advanced simple profile features such as B-frames , quarter pixel motion compensation (QPel), global motion compensation (GMC) and custom quantizer matrices . The codec supports the H.263 standard, but so far not the more efficient H.264 / AVC standard (as of 2020).

history

In January 2001, founded DivXNetworks OpenDivX the project as part of Mayo , which is open source - Multimedia to house projects. OpenDivX was an open source MPEG-4 video codec that was written from the ground up; however, the code was placed under a limited license and only members of the DivX Advanced Research Center (DARC) had write access to CVS . In spring 2001, DARC member Sparky wrote an improved version of the encoder core, called encore2 , which was then removed from the CVS without warning. Sparky's statement was, "We (our superiors) decided we weren't ready to show it to the public just yet" (translated).

In July 2001, the developers began to complain about a lack of activity in the project since the last source code change was already months ago, improvements of program errors were ignored and the promised documentation had not appeared. Shortly thereafter, DARC released a beta version of their closed source and commercial DivX-4 codec, which was based on encore2 , with the declaration “What the community really wants is a Winamp , not a Linux ” (translated). Some accused DivXNetworks of just starting OpenDivX to collect other people's ideas and then use them in their DivX-4 codec; some were disappointed that code development had stagnated but wanted to keep working on it, while still others were angry at the way DivXNetworks is handling what is known as an open source project. After that, a fork was created by OpenDivX using the latest version of encore2 that was available for download before it was removed. Since then, all of the OpenDivX code has been replaced and Xvid has been released and developed under the GPL.

Sigma Designs Controversy

In July 2002, Sigma Designs released an MPEG-4 video codec called REALmagic MPEG-4 Video Codec . After a short time it was found out that it contained part of the Xvid code. Sigma Designs was notified and confirmed that a programmer had built REALmagic on top of Xvid - but also promised to replace the GPL code in order to avoid copyright infringement .

When Sigma Designs released the supposedly rewritten REALmagic codec, the Xvid developers decompiled it again and found that it still contained Xvid code; just rearranged in an attempt to disguise the origin. The Xvid developers then decided to suspend their work on Xvid and go public in order to force Sigma Designs to comply with the terms of the GPL. After Slashdot and The Inquirer reported on this, Sigma Designs agreed to open the source code for their REALmagic MPEG-4 video codec .

Encoder

When installing the Xvid package, an encoder is also installed, which enables files to be easily converted to the MPEG4 standard.

The programs VirtualDub , Avidemux , MEncoder or FFmpeg can be used to encode videos as Xvid .

See also

swell

  1. a b www.openhub.net .
  2. websvn.xvid.org . (accessed on September 24, 2017).
  3. http://lists.xiph.org/pipermail/vorbis/2001-August/004220.html
  4. http://slashdot.org/articles/02/08/22/193237.shtml?tid=117
  5. http://www.theinquirer.net/inquirer/news/1029663/xvid-asks-sigma-to-stop-copyright-breach

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