Overview

The DivX® media format is widely recognized by consumers, software developers, hardware manufacturers, content providers and other commercial entities as the standard for high-quality digital video.

Video enthusiasts worldwide have already created billions of DivX videos using various software applications that integrate DivX technology and many more are consuming that content on a range of different platforms.

For our partners, adding DivX support is a key differentiator that attracts consumers to their products. Licensing DivX software:

  • Ensures interoperability with the valuable ecosystem of DivX products
  • Makes it easy for users to create or play high-quality digital video
  • Enables DivX video support across a range of platforms

Learn more about software integration, volume licensing orcontent production licensing, and contact us for more information.

 

http://www.divx.com/en/partner/software-licensing

DivX

From Wikipedia, the free encyclopedia

This article is about the video codec. See DivX, Inc. for the company behind the codec. For the failed videodisc format, see DIVX.

Series of articles on DivX

Divx logo.svg

DivX

DivX, Inc.

Dr. DivX

DivX Plus HD

Stage6

DivX is a brand name of products created by DivX, Inc. (formerly DivXNetworks, Inc.), including the DivX Codec which has become popular due to its ability to compress lengthy video segments into small sizes while maintaining relatively high visual quality.

There are two DivX codecs; the regular MPEG-4 Part 2 DivX codec and the H.264/MPEG-4 AVC DivX Plus HD codec. It is one of several codecs commonly associated with "ripping", whereby audio and video multimedia are transferred to a hard disk andtranscoded.

Contents

[hide]

[edit]History

The "DivX" brand is distinct from "DIVX" (Digital Video Express), an unrelated attempt by the now defunct U.S. retailer Circuit City to develop a video rental system requiring special discs and players.[1] The winking emoticon in the early "DivX ;-)" codec name was a tongue-in-cheek reference to the failed DIVX system. The DivX company then adopted the name of the popular DivX ;-) codec (which was not created by them), dropped the smiley and released DivX 4.0, which was actually the first DivX version. (Note that DivX ;-) and DivX are separate products and are created by different people; the former is not an older version of the latter). The DivX name is its trademark.[2][3] It is pronounced DIV-ex.

[edit]Early works

DivX ;-) (not DivX) 3.11 Alpha and later 3.xx versions refers to a hacked version of the Microsoft MPEG-4 Version 3 video codec (not to be mistaken with MPEG-4 Part 3) from Windows Media Tools 4 codecs.[4][5] The video codec, which was actually not MPEG-4 compliant, was extracted around 1998 by French hacker Jerome Rota(also known as Gej) at Montpellier. The Microsoft codec originally required that the compressed output be put in an ASF file. It was altered to allow other containerssuch as Audio Video Interleave (AVI).[6] Rota hacked the Microsoft codec because newer versions of the Windows Media Player wouldn't play his video portfolio and résumé that were encoded with it. Instead of re-encoding his portfolio, Rota and German hacker Max Morice decided to reverse engineer the codec, which "took about a week".[7]

[edit]Later works

In early 2000, Jordan Greenhall recruited Rota to form a company (originally called DivXNetworks, Inc., renamed to DivX, Inc. in 2005) to develop an MPEG-4 codec, from scratch, that would still be backward-compatible with the Microsoft MPEG-4 Version 3 format. This effort resulted first in the release of the "OpenDivX" codec and source code on 15 January 2001. OpenDivX was hosted as an open-source project on the Project Mayo web site hosted at projectmayo.com[8] (the name comes from "mayonnaise", because, according to Rota, DivX and mayonnaise are both "French and very hard to make."[7]). The company's internal developers and some external developers worked jointly on OpenDivX for the next several months, but the project eventually stagnated.

In early 2001, DivX employee "Sparky" wrote a new and improved version of the codec's encoding algorithm known as "encore2". This code was included in the OpenDivX public source repository for a brief time, but then was abruptly removed. The explanation from DivX at the time was that "the community really wants a Winamp, not a Linux." It was at this point that the project forked. That summer, Rota left the French Riviera and moved to San Diego "with nothing but a pack of cigarettes"[9] where he and Greenhall founded what would eventually become DivX, Inc.[7]

DivX took the encore2 code and developed it into DivX 4.0, initially released in July 2001. Other developers who had participated in OpenDivX took encore2 and started a new project—Xvid—that started with the same encoding core. DivX, Inc. has since continued to develop the DivX codec, releasing DivX 5.0 in March 2002. By the release of version 5.2.1 on 8 September 2004, the DivX codec was substantially feature-complete.[10][dead link] Changes since then have tended to focus on speed, and encouraging wider hardware player support, while the company has also focused its time on the formats and next generation codecs.

[edit]DivX formats

[edit]DivX Media Format (DMF)
DivX Media Format

DivX media container icon

Filename extension
.divx

Type code
DIVX

Developed by
DivX, Inc.

Type of format
media container

Container for
MPEG-4 Part 2–compliant video

Extended from
AVI

DivX 6 expanded the scope of DivX from including just a codec and a player by adding an optional media container formatcalled "DivX Media Format" ("DMF")[11] (with a .divx extension) that includes support for the following DVD-Video and VOBcontainer like features. This media container format is used for the MPEG-4 Part 2 codec.

  • DivX Media Format (DMF) features:
    • Interactive video menus
    • Multiple subtitles (XSUB)
    • Multiple audio tracks
    • Multiple video streams (for special features like bonus/extra content, just like on DVD-Video movies)
    • Chapter points
    • Other metadata (XTAG)
    • Multiple format
    • Partial backwards compatibility with AVI

This new "DivX Media Format" also came with a "DivX Ultra Certified" profile, and all "Ultra" certified players must support all "DivX Media Format" features. While video encoded with the DivX codec is an MPEG-4 video stream, the DivX Media Format is analogous to media container formats such as Apple's QuickTime. In much the same way that media formats such as DVD specify MPEG-2 video as a part of their specification, the DivX Media Format specifies MPEG-4-compatible video as a part of its specification. However, despite the use of the ".divx" extension, this format is an extension to the AVI file format. The methods of including multiple audio and even subtitle tracks involve storing the data in RIFF headers and other such AVI hacks which have been known for quite a while, such that even VirtualDubMod supports them. DivX, Inc. did this on purpose to keep at least partial backwards compatibility with AVI, so that players that do not support the new features available to the .divx container format (like interactive menus, chapter points and XSUB subtitles) can at least play that primary video stream (usually the main movie if the DMF file contains multiple video streams like special features like bonus materials). Of course, the DivX codec and tools like Dr. DivX still support the traditional method of creating standard AVI files.

[edit]DivX Plus HD

Main article: DivX Plus HD

DivX Plus HD is a marketing name for a file type using the standard Matroska media container format (.mkv), rather than the proprietary DivX Media Format. DivX Plus HD files contain an H.264 video bitstream, AAC surround sound audio, and a number of XML-based attachments defining chapters, subtitles and meta data.[12] This media container format is used for the H.264/MPEG-4 AVC codec.

[edit]DivX profiles

Gnome globe current event.svg

This article is outdated. Please update this article to reflect recent events or newly available information. Please see thetalk page for more information. (October 2010)

DivX has defined profiles which are subsets of MPEG-4/AVI and H.264/Matroska standards. Because the grouping is a specific subset of what is in the standards, there are certification processes for each of the profiles that device manufacturers must follow. Hence all DivX certified devices bearing a DivX logo will adhere to one of the profiles outlined in the table below as would any tools that support the DivX profiles.[13][14]

Profiles

Mobile
Mobile Theater
Home Theater
HD 720p
HD 1080p
+HD 1080p

DivX Codec (MPEG-4 Part 2)
5,6
5,6
3,4,5,6
5,6
3,4,5,6
n/a

DivX H.264 Codec (MPEG-4 Part 10)
n/a
n/a
n/a
n/a
n/a
1.x

File Extension(s)
.avi, .divx
.avi, .divx
.avi, .divx
.avi, .divx
.avi, .divx
.mkv

Max. resolution (px×px×Hz)
320x240×30
640x480×30
720×480×30, 720×576×25
1280×720×30
3/4:

720×480×30, 720×576×25

5/6:

1920×1080×30, 1280×720×60

1920×1080×30,

1280×720×60

Max VBV bitrate (bit/s)
600000
4854000
4854000
9708400
20000000
VCL: 20000000,

NAL: 24000000

Min. VBV buffer size (KiB)
80
384
384
768
2097
VCL: 3200, NAL: 3840

Macroblocks (per second)
9000
40500
40500
108000
3/4: 40500

5/6: 244800

244800

Subtitles
optional
optional
8×XSUB[15]
8×XSUB
8×XSUB,XSUB+
8×SRT[16],SSA[17]

Audio
1×MP3
1×MP3
8×MP3,MP2,AC3
8×MP3,AC3
8×MP3,MP2,AC3
8×MP3,AC3,AAC

[edit]DivX Video on Demand

DivX Video on Demand (DivX VOD) is DivX's version of digital rights management (DRM), which allows content owners to control distribution in an effort to thwart piracy. DivX, Inc. has received format approval from major Hollywood studios including Sony, Paramount and Lionsgate, which has allowed content retailers to sell protected videos that will play on current and previous generations of DivX certified devices.[18]

[edit]DivX software

The DivX codec, DivX Plus Software for Windows and DivX 7 for Mac are available as free downloads at the DivX website.

On the 6 January 2009, DivX 7 was released, which added H.264 video, AAC audio and Matroska container support, surpassing the restrictions of the previous formats.[19]

[edit]DivX Plus Software for Windows

On the 16 March 2010, DivX Plus Software (version 8) for Windows was released, which introduced the DivX Plus Codec Pack and DivX to Go integration in the DivX Plus Player.[20]

[edit]DivX Plus Player
DivX Plus Player

DivX Plus Player interface

Developer(s)
DivX, Inc.

Stable release
8.0.1 / 4 June 2010; 8 months ago

Operating system
Microsoft Windows

Type
Media player

License
Freeware

Website
http://www.divx.com/software/divx-plus/player

DivX Plus Player (version 8) is a standalone media player.[21] This player is a successor to DivX Player(versions 6 and 7) and Playa (version 5), made by the Project Mayo team that later became DivX, Inc.[citation needed]

DivX Plus Player also features DivX to Go as an additional panel on the right side of the interface with four buttons targeting consumer electronic devices. When a user drags a video file onto one of the icons, a transfer wizard is invoked, which walks the user through the steps needed to convert and transfer a video file that's compatible with their DivX Certified device, via USB or optical disc.

DivX Plus Player also features a media library as well as a set of Digital Rights Management features that help authorize purchased commercial contents for the consumer's computer and his DivX Certified devices.[21]

[edit]Supported formats

DivX Plus Player supports the following media formats:[21]

File formats
Video compression algorithms
Audio compression algorithms

— Native support —

Advanced Systems Format
.wmv, .asf
H.264
Advanced Audio Coding

Audio Video Interleave
.avi
MPEG-4 ASP
MPEG-1 Audio Layer 3

DivX Format
.divx
Windows Media Video
Windows Media Audio

Matroska
.mkv
Vorbis

MPEG-4 Part 14
.mp4

QuickTime Format
.mov

SubRip
.srt

SubStation Alpha
.ssa, .ass

— Extended support —

MPEG-1
.mpg, .mpe, .mpeg, .m1v
MPEG-1 Video
MPEG-1 Audio Layer I

MPEG-2
.vob, .ts, .m2v
MPEG-2 Video
MPEG-1 Audio Layer II

RMVB
.rmvb
RealVideo
RealAudio

M2TS
.m2ts, .mts
Dolby Digital(AC-3)

DTS

L-PCM

Legend

Has native support in DivX Plus

Requires external components installed

[edit]DivX Plus Converter
DivX Plus Converter

DivX Plus Converter interface

Developer(s)
DivX, Inc.

Stable release
8.0.1.49 / 4 June 2010; 8 months ago

Operating system
Microsoft Windows

Type
Video converter

License
Converter: Freeware
Converter Pro: Proprietarycommercial software

Website
http://www.divx.com/software/divx-plus/converter

The DivX Plus Converter (version 8) introduced a dramatically changed interface from its predecessor. The former had a small round interface that allowed for little more than selecting the type of output and displayed the number of videos in the queue. The DivX Plus Converter interface contains a large window that exposes each video that has been added in a row with drop-down options for quality, size, audio, subtitles and more. Another notable change is while both the previous and DivX Plus versions have 15-day trials, the DivX Plus Converter still allows users to create DivX Plus HD files for free after the trial is complete.[22]

DivX Plus Converter can convert AVI files (.avi), MP4 files (.mp4), QuickTime Video files (.mov), Windows Media Video files (.wmv), AVCHD video files (.mts and .m2ts) and RMVB files (.rmvb) to DivX Plus HD format (.mkv files). When a DivX Pro license is purchased, it can also convert video files to DivX Media Format (.divx files). In addition with the purchase of an "MPEG-2/DVD Plug-in", the input support range of DivX Plus Converter will be extended to support MPEG video, MPEG-2 video, DVD Video and Video CD.[22]

[edit]DivX Plus Codec Pack

This section does not cite any references or sources.
Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (April 2010)

The DivX Plus Codec Pack is an upgrade to the former DivX Community Codec, which enables system-wide playback of MPEG-4 ASP and H.264 video (DivX Plus files) via DirectShow and Media Foundation components. This pack includes a free H.264 decoder with optional DXVA hardware acceleration that can be activated in the control panel.

Customers that pay for DivX Pro can access additional features[which?] of the DivX codec in Video for Windows applications.

[edit]DivX Plus Web Player
DivX Plus Web Player

DivX Plus Web Player interface

Developer(s)
DivX, Inc.

Stable release
2.0.2 / 16 March 2010; 10 months ago

Operating system
Microsoft Windows / Mac OS X

Type
Media player

License
Freeware

Website
http://www.divx.com/software/divx-plus/web-player

DivX Plus Web Player (formerly known as DivX Web Player and DivX Browser Plug-In) is a web browser plug-in for playing embedded files hosted on a publisher's HTTP web server, and is capable of HD and surround sound playback inside major browsers[which?] for Windows and Mac OS.[23]

[edit]Features
  • Windows browser plug-in for Internet Explorer, Firefox and Chrome
  • Mac OS browser plug-in for Safari (32-bit) and Firefox
  • Plays embedded DivX/Xvid encoded .divx or .avi files with MP3 audio
  • Also plays embedded DivX Plus HD, or H.264 video with AAC audio in .mkv
  • Supports multiple audio tracks and muxed UTF-8 subtitles
  • Video file can be saved locally upon completing of full-length buffer
  • JavaScript interface for web developers: DivX Developer Portal
[edit]Beta 2.1 and DivX HiQ

On September 2, 2010, a public beta introduced the following features in the DivX Plus Web Player for Windows:[24]

  • DivX HiQ™ allows users to switch from a site's Flash player to the DivX Plus Web Player on video portals likeYouTube, DailyMotion, and others.[25]
  • Additional file format container support for H.264 video in MP4 or MOV.
  • HTML5 <video> tag support for embedding .divx, .avi, .mkv, .mp4 or .mov video.
  • Hardware accelerated video decoding of H.264 bitstreams via DXVA.
[edit]DivX 7 for Mac
[edit]DivX Player for Mac
DivX Player for Mac

DivX Player for Mac interface

Developer(s)
DivX, Inc.

Stable release
7.2.3 / 17 November 2009; 14 months ago

Operating system
Mac OS X

Type
Media player

License
Freeware

Website
http://www.divx.com/en/software/mac/

DivX Player for Mac, first introduced with DivX 6.5 on the 25 May 2006, is a standalone player that plays DivX encoded files and DivX Media Format features such as subtitles, multiple audio tracks, and DivX VOD content. The DivX Player for Mac also can play DivX Plus HD compatible files — namely .mkv files encoded with H.264 video and AAC audio. Unlike the DivX 7 and DivX Plus (version 8) Windows counterparts, DivX Player for Mac does not include a burn engine or a utility for moving videos to USB.

[edit]Features
  • Bundled playback of MPEG-4 ASP video with MP3 audio (.divx/.avi) and DivX Plus files (Matroska with H.264 video and AAC audio)
  • Mouse gestures to control video
  • Media manager via a video library window
  • Play any QuickTime supported file
  • Play video as desktop background
  • Manage certified DivX devices to enable playback of purchased/protected content
  • Playback of purchased/protected video content
[edit]DivX Converter for Mac

DivX Converter for Mac has remained virtually unchanged since DivX 6 for Mac, which is most apparent in its small and round interface and lack of ability to generate DivX Plus HD files.

[edit]DivX Plus Web Player for Mac

As of DivX Plus Web Player version 2.0.2, DivX Plus Web Player for Mac has feature parity with the DivX Plus Web Player for Windows.

[edit]Community applications
[edit]Dr. DivX OSS

Main article: Dr. DivX

Dr. DivX OSS 2 for Windows

Dr. DivX is an application created by DivX, Inc. that is capable of transcoding many video formats to DivX encoded video. The original closed source Dr. DivX terminated at version 1.06 for DivX 5.21, that was the last version of DivX capable of running under Windows 9x/Me. An open source version has been made, which supports DivX 6. Dr. DivX offers greatly expanded features over the free DivX Converter application, that was bundled with the codec from version 6 onwards.[26] Dr. Divx is not compatible with DivX Plus HD.

[edit]DivX H.264 encoder

DivX has released a command line interface (CLI) for the divx264 encoder used in the DivX Plus Converter as beta, free for non-commercial use.[27] Since it can only create raw H.264 streams a Matroska muxer must be used.

[edit]DivX AAC encoder

To complement the CLI divx264 encoder released on DivX Labs, DivX has also released a DivX AAC encoder CLI as a Windows beta binary.[27] Since it can only create raw AAC streams, a Matroska muxer must be used.

[edit]DivX MKV Mux

The DivXMKVMux is a free Windows CLI available through DivX Labs with documentation on the DivX Developer Portal; DivX describes the release as a reference mux to demonstrate DivX Plus MKV extensions like World Fonts and Smooth FF/RW.[28]

[edit]Hardware support

DivX, Inc. markets a certification program to consumer electronics and IC manufacturers for the purpose of guaranteed compatibility and playback of video files that fall within DivX profiles. Devices that have been DivX certified usually brandish one of the following marks:[29]

  • DivX Certified
  • DivX Certified for HD 720p and 1080p
  • DivX Certified for DivX Plus HD
  • DivX Connected
  • DivX Certified for DivX Ultra

DivX certified devices have included DVD players, car stereos, mobile phones, televisions, blu-ray players, and even alarm clocks.[30]

Aside from verifying proper decoding of files conforming to the DivX profiles the certification also confirms the device can play back DivX Video on Demand content, which includes Hollywood content that can be purchased from Internet retailers.[31]

[edit]Gaming system compatibility

The PlayStation 3button on the DivX to Go interface of the DivX Plus Player.

On 4 December 2007, native MPEG-4 ASP playback support was added to the Xbox 360,[32][dead link] allowing it to play video encoded with DivX and other MPEG-4 ASP codecs.[33]

On 17 December 2007, firmware upgrade 2.10 was released for the Sony PlayStation 3, which included official DivX Certification. Firmware version 2.50 (released on 15 October 2008) included support for the DivX Video on Demand (DivX VOD) service, and firmware version 2.60 (released on 20 January 2009) included official DivX Certification and updated Profile support to version 3.11.[34]

With introduction of DivX to Go in the DivX Plus Player for Windows, a PlayStation 3 icon is readily available on the interface, which will invoke a transfer wizard for freely converting and copying video files via USB or optical disc.[35] The output from DivX to Go's PlayStation 3 preset is also playable on the Xbox 360.

[edit]Competitors

The main competitors of DivX Inc. in the proprietary commercial software market are Microsoft corporation and Apple Inc. Microsoft develops Windows Media Videotechnology as well as Windows Media Player, a video and Windows Media Encoder, a video converter. Apple Inc. also develops QuickTime, a suite of encoding and playback software as well as multimedia framework.

Additionally, all software products that create (encode) MPEG-4–compatible digital video also compete with DivX. One of these products that can produce MPEG-4–compliant digital video is Xvid, a free and open source codec that offers comparable quality. Both DivX Codec and Xvid are compliant with MPEG-4 Part 2 (MPEG-4 ASP); however, the most commonly used DivX encoding profile (Home Theater)[36] does not employ the same MPEG-4 ASP features enabled in the most commonly used Xvid encoding profile (home).[37] In a series of subjective quality tests at Doom9.org between 2003 and 2005, the DivX encoder was beaten by the Xvid encoder every year.[38] Similar tests were not undertaken for newer versions.

Another notable product is libavcodec, a free software library that can create and play MPEG-4–compliant digital video. This library is now part of ffdshow, which can be used for playback with most Windows video players and video converters.

Note however, that unlike DivX Plus, neither Xvid nor ffdshow include a standalone video players or video converters; thus they are not directly usable by consumers.

See also: Comparison of video player software and Category:Video conversion software

[edit]See also

Related technologies
General Topics

http://en.wikipedia.org/wiki/DivX

 

위키백과, 우리 모두의 백과사전.

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이 문서는 위키백과의 편집 지침에 맞춰 다듬어야 합니다.
더 좋은 문서가 되도록 문서 수정을 도와주세요. 내용에 대한 의견이 있으시다면 토론 문서에서 나누어 주세요.

Xvid

최근 버전
1.2.2 / 2009년 5월 29일

운영 체제
크로스 플랫폼

종류
영상 코덱

라이선스
GNU 일반 공중 사용 허가서

웹사이트
Xvid(XviD) 공식 홈페이지

Xvid(이전 명칭은 XviD)는 MPEG-4 표준을 따르는 영상 코덱 라이브러리이다. Xvid는 b-프레임, 전체와 1/4 화소 움직임 보상, 루미 마스크, 격자 양자화와 같은 MPEG-4 진보된 단순 프로필 기능을 지원한다. H.263, MPEG과 커스텀 양자화 매트릭스 등도 지원한다.

Xvid는 DivX(Xvid는 DivX를 거꾸로 씀)의 첫 번째 경쟁 코덱이다. DivX는 상용 소프트웨어이지만, Xvid는 자유/오픈 소스 소프트웨어이고, 마이크로소프트 윈도맥 OS X만을 지원하는 DivX와는 대조적으로, Xvid는 다양한 플랫폼과 운영 체제에서 사용될 수 있다.

목차

[숨기기]

[편집]역사

2001년 1월에 DivX네트워크는 오픈소스 멀티미디어 프로젝트에 적합하게 의도된 프로젝트 마요의 일부인 “오픈DivX”를 설립하였다. 오픈Divx는 모무시스 참조 MPEG-4 인코더의 폭로된 하위 버전을 기반으로 만들어진 오픈소스 MPEG-4 영상 코덱이다. 그러나 소스코드는, 제한된 라이선스로 제공되어 DivX 고급 연구 센터(DARC)의 회원만 개발 계획 CVS에 접근해서 기록했다. 2001년 초에, DARC 회원 스파키(Sparky)는 인코어2라고 불리는 인코딩 코어의 향상된 버전을 활발하게 개발하였다. 이전에 몇 번씩 업데이트되었고, 4월에, 어떤 안내없이 CVS에서 제거되었다. 스파키는 “우리(우리의 사장)는 아직 공개할 준비가 안되었다고 결정하였다.”라고 변명하였다.

2001년 7월에, 개발자들은 개발 진행이 더디게 진행되는 것에 대하여 불평하기 시작하였다. 마지막 CVS 게시물는 수개월 동안 방치되고, 버그 수정은 무시되었으며, 보증된 코드는 기록되지 않았다. 얼마 뒤에, DARC는 인코어2 기반인, 클로즈소스 상용 DivX 4 코덱의 베타버전을 발표하였으며, “공동체가 원하는 것은 윈앰프이지, 리눅스가 아니다”라고 말했다. 대중은 DivX4의 용도가 수익 목적으로 판매하기 위해 오픈DivX로 시작한 DivX네트워크를 고소했으며, 어떤 사람은 코덱이 정체된 것에 실망하였고 개발 계획이 계속 작업되기를 원했다. 반면에 다른 사람은 DivX네트워크가 소위 오픈소스 프로젝트를 처리하는 방법에 대하여 분노했다.[출처 필요] 오픈DivX의 포크가 생긴 이후에 이 개발 계획은, 인코어2의 마지막 버전이 제거되기 이전에 내려받은 인코어2의 최신 버전을 사용하였다. 그때부터 모든 오픈DivX 코드는 대체되었고, Xvid는 GNU 일반 공중 사용 허가서로 발표하였다.

[편집]법적 문제

Xvid의 어떤 기능은 많은 나라(특히 미국일본)에서 소프트웨어 특허가 숨겨졌다고 여겨진다.[출처 필요] 이런 이유 때문에, Xvid 0.9.x 버전은 이런 특허가 집행되는 나라에서 라이선스를 얻지 못하였다. 1.0.x 발표에서, GNU 일반 공중 사용 허가서 버전 2 라이선스는 명백한 지리적 제한없이 사용된다. 그러나 Xvid의 관습법은 지역법에 따라 여전히 제한될 것이다.[1]

[편집]시그마 디자인 논쟁

2002년 7월, 시그마 디자인은 리얼매직 MPEG-4 영상 코덱이라고 불리는 MPEG-4 영상 코덱을 발표하였다. 오래전에 이 새로운 코덱을 테스트하던 사람은 Xvid 코덱의 상당한 부분을 포함하고 있음을 발견했다. 시그마 디자인은 프로그래머가 리얼매직을 Xvid기반임을 연락해서 확인됐지만, 저작권 침해를 피하기 위해 모든 일반 공중 사용 허가서 코드는 대체되었다. 시그마 디자인은 아마도 갱신된 리얼매직 코덱을 발표하자, Xvid 개발자는 즉시 역어셈블링하였고, 그것의 존재를 위장하기 위해서 단지 재배치하여, 여전히 Xvid 코드를 포함하고 있다고 결론내렸다. Xvid 개발자는 개발을 멈추기로 결정했고 시그마 디자인이 강제로 일반 공중 사용 허가서의 용어를 존중하기 위해 공개 활동을 하였다. 2002년 8월에 슬래시닷[2]인콰이어[3]에 기사가 공개된 이후에, 시그마 디자인은 소스 코드를 공개하는데 동의했다.[4]

[편집]Xvid 인코딩 파일 재생

특허를 염려하는 것이 첫 번째이기 때문에, 공식 Xvid 홈페이지는 Xvid 코덱의 실행파일 형태로 제공하지 않는다. 그러나 마이크로소프트 윈도 운영체체의 윈도용 비디오 코덱(다이렉트쇼 인코딩 전용 필터를 포함하는)은, 지원하는 웹사이트에서 내려받아 사용할 수 있다. 리눅스 사용자를 위해서, 많은 배포판은MPlayerVLC같은 미디어 재생기로 재생하기 위해 Xvid 코덱을 제공한다. 그러나, 모든 이런 재생기는 기본으로 FFmpeg MPEG-4 인코더를 사용하고 그러므로 Xvid 코덱 인코딩은 요구되지 않는다(또는 지원되지 않는다).

Xvid는 MPEG-4 진보된 단순 프로필(ASP) 압축을 사용하기 때문에, Xvid로 인코딩된 영상은 MPEG-4 ASP 영상이고, 그러므로 대부분의 모든 MPEG-4 ASP 디코더로 디코딩될 수 있다. 이것은 수많은 미디어 재생기를 포함하며, 특히 자유/오픈 소스 libavcodec 라이브러리의 기반인 것이 대부분이다.

Xvid로 인코딩된 파일은 CDDVD에 기록할 수 있다. 그리고 DivX와 호환되는 DVD 재생기에서 재생도 할 수 있다. 그러나 Xvid는 전역 움직임 보상의 실행을 위해서 3개의 감싸는 지점을 기술하기 때문에, 어떤 부분에서 가능한 더 많이 진보된 인코딩 기능은 재생기 호환성을 떨어뜨릴 수 있다. 어떤 문제는 Xvid의 MPEG-4 스트림을 인코딩하는 AutoGK와 같은 도구를 사용하는 기본 양자 매트릭스로 존재한다. 이것은 DivX 호환되는 DVD 재생기에서 불안정한 재생과 인공적인 영상을 발생시킨다.

미디어 재생기의 비교#영상 형식 지원 문서를 참고하십시오.

[편집]주석

  1. 메일 목록 토론 [1], [2], [3]을 보세요.
  2. Slashdot | Sigma Designs Accused of Copyright Infringement
  3. http://www.theinquirer.net/Default.aspx?article=5089
  4. Sigma Designs, Inc. | Digital Media Processing For Consumer Appliances

[편집]같이 보기

[편집]바깥 고리

vdeh

데이터 압축 구현

영상 코덱
(비교)

MPEG-4 ASP
3ivx · DivX · FFmpeg MPEG-4 · HDX4 · Xvid

H.264/MPEG-4 AVC
CoreAVC · HDX4 · QuickTime H.264 · x264

비손실
CorePNG · FFV1 · Huffyuv · Lagarith · MSU 비손실

기타
시네팩 · Dirac · Indeo · VP3 · VP7 · Pixlet · 스노우 · Tarkin · Theora · WMV

음성 코덱
(비교)

일반
ADPCM · ATRAC · 돌비 디지털 · Musepack · TwinVQ · Vorbis · WMA

발음/목소리
iLBC · IMBE · iSAC · QCELP · Speex

비손실
애플 무손실 · 돌비 트루HD · DTS-HD 마스터 오디오 · OptimFROG · FLAC · APE · TTA · WavPack · WMA 무손실

압축
(비교)

오픈 소스
7-Zip · Ark · File Roller · KGB · PeaZip · The Unarchiver

프리웨어
빵집 · 콩집 · 다집 · DGCA · FilZip · GCA · IZArc · TUGZip · Zipeg · ZipGenius · V3 Zip(개인무료) · 압축시대

상용
알집 · BOMArchiveHelper · MacBinary · 파워어카이버 · Squeez · StuffIt · WinAce · WinRAR · WinRK · WinZip · 술집

명령 줄
ARC · ARJ · JAR · bzip2 · compress · gzip · Info-ZIP · LHA · lzop · NABOB · PAQ · PKZIP · RAR · SBC · UPX

분류: 영상 코덱 | 자유 멀티미디어 코덱

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  • 이 문서는 2010년 10월 24일 (일) 11:19에 마지막으로 바뀌었습니다.

http://ko.wikipedia.org/wiki/Xvid

 

From Wikipedia, the free encyclopedia

Adaptive Multi-Rate (AMR)

Filename extension
.amr

Internet media type
audio/amr, audio/3gpp, audio/3gpp2

Initial release
23 June 1999[1][2]

Latest release
9.0.0 / 18 December 2009; 13 months ago

Type of format
Audio compression format, audio file format

The Adaptive Multi-Rate (AMR or AMR-NB) audio codec is a patented audio data compression scheme optimized forspeech coding. AMR was adopted as the standard speech codec by 3GPP in October 1998 and is now widely used in GSMand UMTS. It uses link adaptation to select from one of eight different bit rates based on link conditions.

AMR is also a file format for storing spoken audio using the AMR codec. Many modern mobile telephone handsets can store short audio recordings in the AMR format, and both free and proprietary programs exist (see Software support) to convert between this and other formats, although it should be remembered that AMR is a speech format and is unlikely to give ideal results for other audio. The common filename extension is .amr. There also exists another storage format for AMR that is suitable for applications with more advanced demands on the storage format, like random access or synchronization with video. This format is the 3GPP-specified 3GP container format based on ISO base media file format.[3]

Contents

[hide]

[edit]Usage

The frames contain 160 samples and are 20 milliseconds long.[1] AMR uses different techniques, such as ACELP, DTX, VAD and CNG. The usage of AMR requires optimized link adaptation that selects the best codec mode to meet the local radio channel and capacity requirements. If the radio conditions are bad, source coding is reduced and channel coding is increased. This improves the quality and robustness of the network connection while sacrificing some voice clarity. In the particular case of AMR this improvement is somewhere around S/N = 4-6 dB for usable communication. The new intelligent system allows the network operator to prioritize capacity or quality per base station.

There are a total of 14 modes of the AMR codec, 8 are available in a full rate channel (FR) and 6 on a half rate channel (HR).

Mode
Bitrate (kbit/s)
Channel
Compatible with

AMR_12.20
12.20
FR
ETSI GSM enhanced full rate

AMR_10.20
10.20
FR

AMR_7.95
7.95
FR/HR

AMR_7.40
7.40
FR/HR
TIA/EIA IS-641 TDMA enhanced full rate

AMR_6.70
6.70
FR/HR
ARIB 6.7 kbit/s enhanced full rate

AMR_5.90
5.90
FR/HR

AMR_5.15
5.15
FR/HR

AMR_4.75
4.75
FR/HR

AMR_SID
1.80
FR/HR

[edit]Features

  • Sampling frequency 8 kHz/13-bit (160 samples for 20 ms frames), filtered to 200–3400 Hz.
  • The AMR codec uses eight source codecs with bit-rates of 12.2, 10.2, 7.95, 7.40, 6.70, 5.90, 5.15 and 4.75 kbit/s.
  • Generates frame length of 95, 103, 118, 134, 148, 159, 204, or 244 bits for bit rates 4.75, 5.15, 5.90, 6.70, 7.40, 7.95, 10.2, or 12.2 kbit/s, respectively
  • AMR utilizes Discontinuous Transmission (DTX), with Voice Activity Detection (VAD) and Comfort Noise Generation (CNG) to reduce bandwidth usage during silence periods
  • Algorithmic delay is 20 ms per frame. For bit-rates of 12.2, there is no 'algorithm' look-ahead delay. For other rates, look-ahead delay is 5 ms. Note that there is 5 ms 'dummy' look-ahead delay, to allow seamless frame-wise mode switching with the rest of rates.
  • AMR is a hybrid speech coder which uses Algebraic Code Excited Linear Prediction (ACELP)
  • The complexity of the algorithm is rated at 5, using a relative scale where G.711 is 1 and G.729a is 15.
  • PSQM testing under ideal conditions yields Mean Opinion Scores of 4.14 for AMR (12.2 kbit/s), compared to 4.45 for G.711 (u-law)
  • PSQM testing under network stress yields Mean Opinion Scores of 3.79 for AMR (12.2 kbit/s), compared to 4.13 for G.711 (u-law)

[edit]Licensing and patent issues

AMR codecs incorporate several patents of Nokia Corporation, Telefonaktiebolaget L. M. Ericsson, VoiceAge Corporation and Nippon Telegraph and TelephoneCorporation.[4][5] VoiceAge Corporation is the License Administrator for the AMR and AMR-WB+ patent pools. VoiceAge also accepts submission of patents for determination of their possible essentiality to these standards.[6][7]

The initial fee for professional content creation tools and "real-time channel" products is $6,500. The minimum annual royalty shall be $10,000, excluding the initial fee in year 1 of the license agreement.[4][5]

AMR decoder in a category of personal computer products (e.g. media players) is licensed for free. The license fee for a sold encoder is $0.40. The minimum annual royalty will not apply to licensed products which fall under category of personal computer products and which contain only the free decoder.[4][5]

For more information about this, please refer to:

[edit]Software support

[edit]See also

[edit]References

  1. ^ a b 3GPP. "3GPP TS 26.090 - Mandatory Speech Codec speech processing functions; Adaptive Multi-Rate (AMR) speech codec; Transcoding functions". Retrieved 2010-07-21.
  2. ^ 3GPP. "3GPP TS 26.090 - Mandatory Speech Codec speech processing functions; Adaptive Multi-Rate (AMR) speech codec; Transcoding functions". Retrieved 2010-07-21.
  3. ^ RFC 4867 - RTP Payload Format and File Storage Format for the Adaptive Multi-Rate (AMR) and Adaptive Multi-Rate Wideband (AMR-WB) Audio Codecs Page 35
  4. ^ a b c VoiceAge Corporation (2007-10-14). "AMR Licensing Terms". VoiceAge Corporation. Retrieved 2009-09-12.
  5. ^ a b c VoiceAge Corporation (2007-06). "AMR Licensing Terms". VoiceAge Corporation. Retrieved 2009-09-12.
  6. ^ VoiceAge Corporation. "Licensing - Patent Calls". VoiceAge Corporation. Retrieved 2009-09-12.
  7. ^ VoiceAge Corporation (2007-10-14). "Licensing - Patent Calls". Archive.org. Archived from the original on 2007-10-14. Retrieved 2009-09-12.
  8. ^ 3GPP (2008-12-11) 3GPP TS 26.073 - AMR speech Codec, Retrieved 2009-09-08
  9. ^ Retrieved on 2010-02-28
  10. ^ FFmpeg General Documentation - AMR external library, Retrieved on 2009-07-08
  11. ^ Android AMR codecs, Retrieved on 2009-07-08

[edit]External links

[hide]v · d · eMultimedia compression and container formats

Video

ISO/IEC

MJPEG · Motion JPEG 2000 · MPEG-1 · MPEG-2 (Part 2) · MPEG-4 (Part 2/ASP · Part 10/AVC) · HEVC

ITU-T

H.120 · H.261 · H.262 · H.263 · H.264 · HEVC

Others

AVS · Bink · CineForm · Cinepak · Dirac · DV · Indeo · Microsoft Video 1 · OMS Video · Pixlet · RealVideo · RTVideo · SheerVideo · Smacker ·Sorenson Video & Sorenson Spark · Theora · VC-1 · VC-2 · VC-3 · VP3 · VP6 · VP7 · VP8 · WMV

Audio

ISO/IEC

MPEG-1 Layer III (MP3) · MPEG-1 Layer II (Multichannel) · MPEG-1 Layer I · AAC · HE-AAC · MPEG Surround · MPEG-4 ALS · MPEG-4 SLS ·MPEG-4 DST · MPEG-4 HVXC · MPEG-4 CELP

ITU-T

G.711 · G.718 · G.719 · G.722 · G.722.1 · G.722.2 · G.723 · G.723.1 · G.726 · G.728 · G.729 · G.729.1

Others

AC-3 · AMR · AMR-WB · AMR-WB+ · Apple Lossless · ATRAC · CELT · DRA · DTS · EVRC · EVRC-B · FLAC · GSM-HR · GSM-FR · GSM-EFR · iLBC ·iSAC · Monkey's Audio · TTA (True Audio) · MT9 · A-law · μ-law · Musepack · Nellymoser · OptimFROG · OSQ · QCELP · RealAudio · RTAudio ·SD2 · SHN · SILK · Siren · SMV · Speex · SVOPC · TwinVQ · VMR-WB · Vorbis · WavPack · WMA

Image

ISO/IEC/ITU-T

JPEG · JPEG 2000 · JPEG XR · lossless JPEG · JBIG · JBIG2 · PNG

Others

APNG · BMP · DjVu · EXR · GIF · ICER · ILBM · MNG · PCX · PGF · TGA · QTVR · TIFF · WBMP · WebP

Containers

ISO/IEC

MPEG-PS · MPEG-TS · ISO base media file format · MPEG-4 Part 14 · Motion JPEG 2000 · MPEG-21 Part 9

ITU-T

H.222.0 · T.802

Others

3GP and 3G2 · AMV · ASF · AIFF · AVI · AU · Bink · DivX Media Format · DPX · EVO · Flash Video · GXF · M2TS · Matroska · MXF · Ogg ·QuickTime File Format · RealMedia · REDCODE RAW · RIFF · Smacker · MOD and TOD · VOB · WAV · WebM

See Compression methods for methods and Compression software implementations for codecs

Categories: Speech codecs

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  • This page was last modified on 6 February 2011 at 19:38.

http://en.wikipedia.org/wiki/Adaptive_Multi-Rate_audio_codec

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