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	<id>https://arolstar52-zhtest.hf.space/index.php?action=history&amp;feed=atom&amp;title=Theora</id>
	<title>Theora - 版本历史</title>
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		<title>imported&gt;Ottokang：​更新版本</title>
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		<updated>2026-03-07T00:54:30Z</updated>

		<summary type="html">&lt;p&gt;更新版本&lt;/p&gt;
&lt;p&gt;&lt;b&gt;新页面&lt;/b&gt;&lt;/p&gt;&lt;div&gt;{{noteTA&lt;br /&gt;
|G1=IT&lt;br /&gt;
|1=zh-hant:智慧財產;zh-hans:知识财产;&lt;br /&gt;
}}&lt;br /&gt;
&lt;br /&gt;
{{Infobox file format&lt;br /&gt;
| name                   = Theora&lt;br /&gt;
| logo                   = Theora logo 2007.svg&lt;br /&gt;
| extension              = &amp;lt;code&amp;gt;.ogv, .ogg&amp;lt;/code&amp;gt;&lt;br /&gt;
| mime                   = &amp;lt;code&amp;gt;video/ogg&amp;lt;/code&amp;gt;&lt;br /&gt;
| owner                  = [[Xiph.Org基金會]]&lt;br /&gt;
| released               = {{start date|df=yes|2004|06|01}}&amp;lt;ref name= &amp;quot;theora-freeze&amp;quot;&amp;gt;{{cite mailing list | url = http://lists.xiph.org/pipermail/theora-dev/2004-June/001112.html | title = Theora I bitstream freeze | mailinglist = theora-dev | date = 1 June 2004 | last = Giles | first = Ralph | accessdate = 25 September 2009 | archive-date = 2011-09-27 | archive-url = https://web.archive.org/web/20110927161643/http://lists.xiph.org/pipermail/theora-dev/2004-June/001112.html | dead-url = no }}&amp;lt;/ref&amp;gt;&lt;br /&gt;
| type code              =&lt;br /&gt;
| genre                  = [[影像編碼]]&lt;br /&gt;
| container for          =&lt;br /&gt;
| contained by           = [[Ogg]]、[[Matroska]]&lt;br /&gt;
| extended from          = [[VP3]]&lt;br /&gt;
| extended to            =&lt;br /&gt;
| free                   = 是&amp;lt;ref&amp;gt;{{cite web|url=http://www.fsf.org/campaigns/playogg/en/|title=PlayOgg! - FSF - Free Software Foundation|accessdate=2013-10-01|date=2010-03-17|archive-date=2017-06-18|archive-url=https://web.archive.org/web/20170618131607/http://www.fsf.org/campaigns/playogg/en|dead-url=yes}}&amp;lt;/ref&amp;gt;&lt;br /&gt;
| standard               = [http://www.theora.org/doc/Theora.pdf Theora規格]&lt;br /&gt;
}}&lt;br /&gt;
&lt;br /&gt;
{{Infobox software&lt;br /&gt;
| name = libtheora&lt;br /&gt;
| logo = &lt;br /&gt;
| screenshot = &lt;br /&gt;
| caption = &lt;br /&gt;
| collapsible = &lt;br /&gt;
| author = &lt;br /&gt;
| developer = [[Xiph.Org基金會]]&lt;br /&gt;
| released = {{start date|df=yes|2008|11|03}} (1.0)&lt;br /&gt;
| discontinued = &lt;br /&gt;
| latest_release_version = 1.2.0&lt;br /&gt;
| latest_release_date = {{Start date and age|df=yes|2025|03|29}}&amp;lt;ref&amp;gt;{{cite web | url = https://www.xiph.org/press/2025/theora-release-1.2/ | title = Theora 1.2.0 release |access-date=29 March 2025 | publisher =Xiph.Org Foundation}}&amp;lt;/ref&amp;gt;&lt;br /&gt;
| latest_preview_version = &lt;br /&gt;
| latest_preview_date = &lt;br /&gt;
| frequently updated = &lt;br /&gt;
| programming language = [[C語言]]&lt;br /&gt;
| operating_system = [[Unix-like]]（包含[[Linux|GNU/Linux]]、[[Mac OS X]]），[[Microsoft Windows|Windows]]&lt;br /&gt;
| operating_system_desc = &lt;br /&gt;
| platform = &lt;br /&gt;
| size = &lt;br /&gt;
| language = &lt;br /&gt;
| status = 停滯&lt;br /&gt;
| genre = [[影像編碼]]&lt;br /&gt;
| license = [[BSD licenses|3-clause BSD]]&lt;br /&gt;
| website = [http://theora.org/ theora.org]&lt;br /&gt;
}}&lt;br /&gt;
&lt;br /&gt;
&amp;#039;&amp;#039;&amp;#039;Theora&amp;#039;&amp;#039;&amp;#039;是一個免權利金、開放格式的[[破壞性資料壓縮|有損]][[影像壓縮]]技術，由[[Xiph.Org基金會]]開發，該基金會還開發了著名的聲音編碼技術[[Vorbis]]，以及多媒體容器檔案格式[[Ogg]]。&amp;#039;&amp;#039;&amp;#039;libtheora&amp;#039;&amp;#039;&amp;#039;則是Xiph.Org基金會針對Theora格式的實作&amp;lt;ref name=&amp;quot;libtheora-xiph&amp;quot;&amp;gt;{{cite web | last= | first= | author=Xiph.Org基金會 | authorlink= | title=libtheora Documentation 1.1.0 | url=http://theora.org/doc/libtheora-1.1/ | format= | accessdate=25 September 2009 | date= | publisher=Xiph.Org基金會 | archive-date=2018-06-24 | archive-url=https://web.archive.org/web/20180624130203/https://www.theora.org/doc/libtheora-1.1/ | dead-url=no }}&amp;lt;/ref&amp;gt;&amp;lt;ref name=&amp;quot;libtheora-ohloh&amp;quot;&amp;gt;{{cite web | last= | first= | author=ohloh | authorlink= | title=libtheora | url=http://www.ohloh.net/p/libtheora | format= | accessdate=25 September 2009 | date= | publisher=ohloh | archive-date=2010-10-10 | archive-url=https://web.archive.org/web/20101010075905/http://www.ohloh.net/p/libtheora | dead-url=no }}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
Theora是由[[On2 Technologies]]公司專屬的[[VP3]]編碼器，經過開放原始碼後衍生而來，目標是達成比[[MPEG-4|MPEG-4 Part 2]]更好的編碼效率。Theora的命名來自於一個電視節目Max Headroom中的角色：Theora Jones&amp;lt;ref&amp;gt;{{cite website| publisher = Xiph.Org基金會| title = Theora FAQ| url = http://theora.org/faq/#15| accessdate = 2009-08-06| archive-date = 2018-06-24| archive-url = https://web.archive.org/web/20180624130008/https://www.theora.org/faq/#15| dead-url = no}}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
== 發展歷史 ==&lt;br /&gt;
=== 開發緣起 ===&lt;br /&gt;
Theora的前身是由On2 Technologies所開發的專屬影像編碼格式&amp;#039;&amp;#039;On2 TrueMotion VP3&amp;#039;&amp;#039;，VP3.1在2000年5月推出，三個月後推出的VP3.2則成為了Theora的基礎&amp;lt;ref&amp;gt;{{cite press release&lt;br /&gt;
 |url         = http://www.on2.com/index.php?id=486&amp;amp;news_id=401&lt;br /&gt;
 |title       = On2 Introduces TrueMotion VP3.2&lt;br /&gt;
 |publisher   = On2&lt;br /&gt;
 |date        = 16 August 2000&lt;br /&gt;
 |accessdate  = 11 August 2009&lt;br /&gt;
 |deadurl     = yes&lt;br /&gt;
 |archiveurl  = https://web.archive.org/web/20071203062255/http://www.on2.com/index.php?id=486&amp;amp;news_id=401&lt;br /&gt;
 |archivedate = 2007年12月3日&lt;br /&gt;
}}&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;{{cite |url=http://www.on2.com/index.php?id=486&amp;amp;news_id=401 |title=On2 Introduces TrueMotion VP3.2（archived website） |author=On2 |date=2000-08-16 |accessdate=2010-08-23 |deadurl=yes |archiveurl=https://web.archive.org/web/20071203062255/http://www.on2.com/index.php?id=486&amp;amp;news_id=401 |archivedate=2007-12-03 }}&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;{{cite press release&lt;br /&gt;
 |url         = http://www.on2.com/index.php?id=486&amp;amp;news_id=407&lt;br /&gt;
 |title       = On2.com Launches Next Generation of Revolutionary Broadband Video Technology&lt;br /&gt;
 |publisher   = On2&lt;br /&gt;
 |date        = 17 May 2000&lt;br /&gt;
 |accessdate  = 11 August 2009&lt;br /&gt;
 |deadurl     = yes&lt;br /&gt;
 |archiveurl  = https://web.archive.org/web/20071203064537/http://www.on2.com/index.php?id=486&amp;amp;news_id=407&lt;br /&gt;
 |archivedate = 2007年12月3日&lt;br /&gt;
}}&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;{{cite |url=http://www.on2.com/index.php?id=486&amp;amp;news_id=407 |title=On2.com Launches Next Generation of Revolutionary Broadband Video Technology（archived website） |author=On2 |date=17 May 2000 |accessdate=2010-08-23 |deadurl=yes |archiveurl=https://web.archive.org/web/20071203064537/http://www.on2.com/index.php?id=486&amp;amp;news_id=407 |archivedate=2007-12-03 }}&amp;lt;/ref&amp;gt;。2001年8月，On2 Technologies宣佈將會釋出一個VP3.2的開放原始碼版本，同年9月在網站www.vp3.com上面釋出VP 3.2的原始碼以及演算法&amp;lt;ref name=&amp;quot;vp32license-archive&amp;quot;&amp;gt;{{cite&lt;br /&gt;
 |title       = VP3.2 Public License 0.1&lt;br /&gt;
 |year        = 2001&lt;br /&gt;
 |author      = On2 Technologies&lt;br /&gt;
 |publisher   = Archive.org&lt;br /&gt;
 |url         = http://vp3.com/license/vp32_opensource_license_9-6-01.txt&lt;br /&gt;
 |accessdate  = 22 September 2009&lt;br /&gt;
 |deadurl     = yes&lt;br /&gt;
 |archiveurl  = https://web.archive.org/web/20011026032511/http://vp3.com/license/vp32_opensource_license_9-6-01.txt&lt;br /&gt;
 |archivedate = 2001年10月26日&lt;br /&gt;
}}&amp;lt;/ref&amp;gt;&amp;lt;ref name=&amp;quot;vp32license-01&amp;quot;&amp;gt;{{cite&lt;br /&gt;
| title = VP3.2 Public License 0.1&lt;br /&gt;
| year = 2001&lt;br /&gt;
| author = On2 Technologies&lt;br /&gt;
| publisher = Xiph.Org基金會&lt;br /&gt;
| url = http://trac.xiph.org/browser/branches/vp32/vp32/VP32_license.txt&lt;br /&gt;
| accessdate = 10 February 2008&lt;br /&gt;
| archive-url = https://web.archive.org/web/20160404101159/https://trac.xiph.org/browser/branches/vp32/vp32/VP32_license.txt&lt;br /&gt;
| archive-date = 2016-04-04&lt;br /&gt;
| dead-url = yes&lt;br /&gt;
}}&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;StreamingMedia.com（2001-09-07）[http://www.streamingmedia.com/article.asp?id=7871 On2 Offers Up VP3.2 Source Code] {{Wayback|url=http://www.streamingmedia.com/article.asp?id=7871 |date=20070814141742 }}, Retrieved on 2009-08-16&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;On2（2001-09-07）[http://www.on2.com/index.php?id=486&amp;amp;news_id=364 On2 Technologies Makes Video Compression Technology Available to Open-Source Community] {{Wayback|url=http://www.on2.com/index.php?id=486&amp;amp;news_id=364 |date=20071207021659 }}, Retrieved on 2009-08-16&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;{{cite |url=http://www.on2.com/index.php?id=486&amp;amp;news_id=364 |title=On2 Technologies Makes Video Compression Technology Available to Open-Source Community（archived website） |author=On2 |date=2001-09-07 |accessdate=2010-08-23 |deadurl=yes |archiveurl=https://web.archive.org/web/20071207021659/http://www.on2.com/index.php?id=486&amp;amp;news_id=364 |archivedate=2007-12-07 }}&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;Linux.com（2001-09-06）[http://www.linux.com/archive/feature/16482 On2 Technologies Open-Sources VP3 video compression code], Retrieved on 2009-08-16&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
=== 轉變為自由軟體 ===&lt;br /&gt;
2002年3月，On2將VP3原始碼的許可認證更改為[[LGPL]]&amp;lt;ref&amp;gt;The Free Library（2002-03-28）[http://www.thefreelibrary.com/On2+Alters+Licensing+Terms+for+VP3%3b+Company+Responds+to+Open+Source...-a084233138 On2 Alters Licensing Terms for VP3; Company Responds to Open Source Community Demands.] {{Wayback|url=http://www.thefreelibrary.com/On2+Alters+Licensing+Terms+for+VP3%3b+Company+Responds+to+Open+Source...-a084233138 |date=20101204092727 }}, Retrieved on 2009-08-16&amp;lt;/ref&amp;gt;；同年6月，On2將VP3以BSD-like的許可認證方式捐贈給Xiph.Org基金會&amp;lt;ref&amp;gt;On2（2002-06-24）[http://www.on2.com/index.php?id=486&amp;amp;news_id=313 VP3 Combines with Vorbis to Create First Open-Source Multimedia Platform] {{Wayback|url=http://www.on2.com/index.php?id=486&amp;amp;news_id=313 |date=20071203061350 }}, Retrieved on 2009-08-16&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;{{cite |url=http://www.on2.com/index.php?id=486&amp;amp;news_id=313 |title=VP3 Combines with Vorbis to Create First Open-Source Multimedia Platform（archived website） |author=On2 |date=2002-06-24 |accessdate=2010-08-23 |deadurl=yes |archiveurl=https://web.archive.org/web/20071203061350/http://www.on2.com/index.php?id=486&amp;amp;news_id=313 |archivedate=2007-12-03 }}&amp;lt;/ref&amp;gt;&amp;lt;ref name=&amp;quot;linux-com-ogg&amp;quot;&amp;gt;Linux.com（2002-06-23）[http://www.linux.com/archive/articles/23630?tid=6 Ogg Vorbis, VP3 combining forces to create Open Source multimedia package], Retrieved on 2009-08-16&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;InternetNews.com（2002-06-24）[http://www.internetnews.com/bus-news/article.php/1370341 On2 Throws More Open-Source at MPEG-4] {{Wayback|url=http://www.internetnews.com/bus-news/article.php/1370341 |date=20110604093151 }}, Retrieved on 2009-08-16&amp;lt;/ref&amp;gt;，並且放棄VP3包含的智慧財產，允使任何人將VP3編碼作更動、衍生&amp;lt;ref name=&amp;quot;theora-license&amp;quot;&amp;gt;Xiph.org [http://svn.xiph.org/trunk/theora/LICENSE libtheora license (Subversion - Trunk)] {{Wayback|url=http://svn.xiph.org/trunk/theora/LICENSE |date=20100207211310 }}, Retrieved on 2009-08-16&amp;lt;/ref&amp;gt;&amp;lt;ref name=&amp;quot;vp32-license&amp;quot;&amp;gt;Xiph.org [http://svn.xiph.org/trunk/vp32/LICENSE VP32 codec license (Subversion - Trunk)] {{Wayback|url=http://svn.xiph.org/trunk/vp32/LICENSE |date=20091003043553 }}, Retrieved on 2009-08-16&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
2002年8月，On2宣佈和Xiph.Org基金會達成-{zh-hant:協議; zh-hans:协议}-，將會以VP3編碼器為基礎，製作一個新的影音編碼格式：Theora。On2認可Theora為VP3的後繼者，在2002年10月3日，On2和Xiph.Org基金會共同完成了Theora的實作：libtheora的最初版本，2003年6月9日，完成了Alpha 2版本&amp;lt;ref name=&amp;quot;libtheora-alpha2&amp;quot;&amp;gt;{{cite mailing list | url = http://lists.xiph.org/pipermail/theora-dev/2003-June/000623.html | title = libtheora alpha 2 release | mailinglist = theora-dev | date = 9 June 2003 | last = Giles | first = Ralph | authorlink =  | accessdate = 26 September 2009 | archive-date = 2011-09-27 | archive-url = https://web.archive.org/web/20110927161649/http://lists.xiph.org/pipermail/theora-dev/2003-June/000623.html | dead-url = no }}&amp;lt;/ref&amp;gt;；2004年3月20日推出了Alpha 3版本&amp;lt;ref name=&amp;quot;libtheora-alpha3&amp;quot;&amp;gt;{{cite mailing list | url = http://lists.xiph.org/pipermail/theora-dev/2004-March/000950.html | title = libtheora alpha 3 release | mailinglist = theora-dev | date = 19 March 2004 | last = Giles | first = Ralph | authorlink =  | accessdate = 26 September 2009 | archive-date = 2011-09-27 | archive-url = https://web.archive.org/web/20110927161741/http://lists.xiph.org/pipermail/theora-dev/2004-March/000950.html | dead-url = no }}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
在VP3開放原始碼時，並沒有針對VP3的位元流格式做規範，2003年，Mike Melanson建立了一個不完整的VP3位元流描述，而後在Theora的規範中採用了部份VP3的位元流描述。&amp;lt;ref name=&amp;quot;theoraspec&amp;quot; /&amp;gt;&amp;lt;ref name=&amp;quot;vp3-bitstream&amp;quot;&amp;gt;{{cite&lt;br /&gt;
 |title       = VP3 Bitstream Format and Decoding Process&lt;br /&gt;
 |date        = 8 December 2004&lt;br /&gt;
 |author      = Mike Melanson（mike at multimedia.cx）&lt;br /&gt;
 |publisher   = Multimedia.cx&lt;br /&gt;
 |url         = http://www.multimedia.cx/vp3-format.txt&lt;br /&gt;
 |accessdate  = 27 September 2009&lt;br /&gt;
 |deadurl     = yes&lt;br /&gt;
 |archiveurl  = https://archive.today/20130106025121/http://www.multimedia.cx/vp3-format.txt&lt;br /&gt;
 |archivedate = 2013年1月6日&lt;br /&gt;
}}&amp;lt;/ref&amp;gt;&lt;br /&gt;
&lt;br /&gt;
Theora的繼任者為[[Daala]]&amp;lt;ref&amp;gt;{{cite news|url=http://www.tomshardware.com/news/ietf-standardizes-netvc-daala-codec,28821.html |author=Lucian Armasu |publisher=Tom&amp;#039;s Hardware |title=IETF Begins Standardization Process For Next-Generation &amp;#039;NETVC&amp;#039; Video Codec (Daala) |date=2015-03-25 |accessdate=2015-08-05}}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
=== Theora I規格 ===&lt;br /&gt;
[[File:I-15bis.ogg|thumb|320px|維基百科上使用Theora影像的範例：一台[[伊-15戰鬥機]]雙翼滑翔機正在表演特技飛行。]]&lt;br /&gt;
&lt;br /&gt;
Theora I位元流格式最終在2004年6月libtheora 1.0alpha3版本釋出後確立&amp;lt;ref name=&amp;quot;theora-freeze&amp;quot;/&amp;gt;，之後只要用libtheora編碼的影像都能夠正確無誤的播放&amp;lt;ref name=&amp;quot;theora-freeze&amp;quot; /&amp;gt;&amp;lt;ref name=&amp;quot;theora-news&amp;quot;&amp;gt;{{cite | title = Theora.org : news | date = 24 September 2009 | author = Xiph.Org基金會 | publisher = Xiph.Org基金會 | url = http://theora.org/news/ | accessdate = 25 September 2009 | archive-date = 2010-10-10 | archive-url = https://web.archive.org/web/20101010214814/http://theora.org/news/ | dead-url = yes }}&amp;lt;/ref&amp;gt;，最終&amp;#039;&amp;#039;Theora I規格&amp;#039;&amp;#039;在2004年正式推出&amp;lt;ref name=&amp;quot;theoraspec-2004&amp;quot;&amp;gt;{{Cite web | last= | first= | author=Xiph.Org基金會 | authorlink= | title=Theora I Specification, Xiph.org基金會, September 17, 2004 | url=http://www.theora.org/doc/Theora_I_spec.pdf | format=PDF | accessdate=26 September 2009 | date=17 September 2004 | publisher=Archive.org | postscript=&amp;lt;!--None--&amp;gt; | deadurl=yes | archiveurl=https://web.archive.org/web/20040928224506/http://www.theora.org/doc/Theora_I_spec.pdf | archivedate=2004年9月28日 }}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
Theora影像的實作libtheora花了數年的時間在測試版狀態，最終正式版1.0版本在2008年11月釋出&amp;lt;ref&amp;gt;{{cite mailing list | url = &lt;br /&gt;
 | title = Theora 1.0 final release! | mailinglist = theora-dev | date = 3 November 2008 | last = Giles |first = Ralph |authorlink= |accessdate=4 November 2008}}&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;{{cite press release&lt;br /&gt;
| title = The Xiph.Org基金會announces the release of Theora 1.0&lt;br /&gt;
| publisher = Xiph.Org基金會&lt;br /&gt;
| date = 3 November 2008&lt;br /&gt;
| url = http://www.xiph.org/press/2008/theora-release-1.0/&lt;br /&gt;
| accessdate = 6 August 2009&lt;br /&gt;
| archive-date = 2009-02-17&lt;br /&gt;
| archive-url = https://web.archive.org/web/20090217223620/http://xiph.org/press/2008/theora-release-1.0/&lt;br /&gt;
| dead-url = no&lt;br /&gt;
}}&amp;lt;/ref&amp;gt;，隨後針對libtheora 1.0版本的作改進的1.1版（代號&amp;#039;&amp;#039;&amp;quot;Thusnelda&amp;quot;&amp;#039;&amp;#039;）也在在2009年11月釋出&amp;lt;ref&amp;gt;{{cite mailing list | url = http://lists.xiph.org/pipermail/theora-dev/2009-September/003985.html | title = libtheora 1.1（Thusnelda）stable release | mailinglist = theora-dev | date = 24 September 2009 | last = Giles | first = Ralph | authorlink =  | accessdate = 24 September 2009 | archive-date = 2010-05-13 | archive-url = https://web.archive.org/web/20100513194452/http://lists.xiph.org/pipermail/theora-dev/2009-September/003985.html | dead-url = no }}&amp;lt;/ref&amp;gt;，1.1版本帶來了許多新特性和改進，像是位元率控制以及[[二次{{}}編碼]]。下個版本的 libtheora 也正在開發中，代號為&amp;#039;&amp;#039;Ptalarbvorm&amp;#039;&amp;#039;&amp;lt;ref name=&amp;quot;ptalarbvorm&amp;quot;&amp;gt;{{Cite web | last =  | first =  | author = Monty | authorlink =  | title = Theora: Ptalarbvorm project update 20100518 | url = http://people.xiph.org/~xiphmont/demo/theora/demo9.html | accessdate = 1 July 2010 | date = 18 May 2010 | publisher =  | postscript = &amp;lt;!--None--&amp;gt; | archive-url = https://web.archive.org/web/20100521172638/http://people.xiph.org/~xiphmont/demo/theora/demo9.html | archive-date = 2010-05-21 | dead-url = yes }}&amp;lt;/ref&amp;gt;，不過目前Theora的程式碼已經近3年沒有重大更新，開發呈現停滯狀態&amp;lt;ref&amp;gt;{{Cite web |url=https://github.com/aptana/studio3/pull/211 |title=存档副本 |accessdate=2014-06-30 |archive-date=2019-02-18 |archive-url=https://web.archive.org/web/20190218044120/https://github.com/aptana/studio3/pull/211 |dead-url=no }}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
隨著Theora逐漸成熟，使用Theora編碼的軟體也逐漸增加，例如維基百科就以Theora作為影片的編碼格式。Theora也曾經被確認為HTML5影像編碼的標準格式，但是在一些爭論之後被撤銷&amp;lt;ref&amp;gt;{{cite web | last = McLean | first = Prince | title = Ogg Theora, H.264 and the HTML 5 Browser Squabble | publisher = RoughlyDrafted Magazine | date = 6 July 2009 | url = http://www.roughlydrafted.com/2009/07/06/ogg-theora-h-264-and-the-html-5-browser-squabble/ | accessdate =2010-02-14| archive-url = https://web.archive.org/web/20101203202243/http://www.roughlydrafted.com/2009/07/06/ogg-theora-h-264-and-the-html-5-browser-squabble/ | archive-date = 2010-12-03 | dead-url = yes }}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
== 技術細節 ==&lt;br /&gt;
Theora是一個[[可變位元速率|變動位元率]]、以[[DCT]]為基礎的影像壓縮格式。和多數的影像編碼格式一樣，Theora使用了[[色度抽樣]]、block based motion compensation和8×8 DCT block，也支援[[intra-coded frames（I-frames）|視訊壓縮圖像類型]]和[[forward predictive frames（P-frames）|視訊壓縮圖像類型]]，但是不支援使用在[[H.264]]和[[VC-1]]的[[視訊壓縮圖像類型|bi-predictive frames（B-frame）]]，Theora也不支援[[隔行掃描]]、可变帧率，或8位以上原色色深。&amp;lt;ref name=&amp;quot;theoraspec&amp;quot;&amp;gt;{{cite website&lt;br /&gt;
| title = Theora Specification&lt;br /&gt;
| year = 2007&lt;br /&gt;
| publisher = Xiph.Org基金會&lt;br /&gt;
| url = http://theora.org/doc/Theora.pdf&lt;br /&gt;
| accessdate = 2009-09-07&lt;br /&gt;
| archive-date = 2012-02-20&lt;br /&gt;
| archive-url = https://www.webcitation.org/65arXwqO2?url=http://theora.org/doc/Theora.pdf&lt;br /&gt;
| dead-url = no&lt;br /&gt;
}}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
Theora的影像流可以儲存在任何的容器檔案格式中，最常用的是和聲音編碼[[Vorbis]]一起儲存在[[Ogg]]檔案格式中，這種方式可以提供完全開放、免權利金的多媒體檔案。此外Theora影像也可以儲存在[[Matroska]]檔案中&amp;lt;ref&amp;gt;{{cite web | publisher = Matroska | title = Matroska Codec Specs | url = http://www.matroska.org/technical/specs/codecid/index.html | accessdate = 2009-08-06 | archive-date = 2009-08-31 | archive-url = https://web.archive.org/web/20090831164352/http://www.matroska.org/technical/specs/codecid/index.html | dead-url = no }}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
== 影像表現 ==&lt;br /&gt;
&lt;br /&gt;
=== 編碼表現 ===&lt;br /&gt;
早期的VP3&amp;lt;ref&amp;gt;{{cite web | publisher = Doom9 | title = MPEG-4 Codec shoot-out 2002 - 1st installment | year = 2002 | url = http://www.doom9.org/codec-comparisons.htm | accessdate = 19 December 2007 | deadurl = yes | archiveurl = https://web.archive.org/web/20080223010804/http://www.doom9.org/codec-comparisons.htm | archivedate = 2008年2月23日 }}&amp;lt;/ref&amp;gt;和Theora&amp;lt;ref&amp;gt;{{cite | publisher = Doom9 | title = Codec shoot-out 2005 - Qualification | year = 2005 | url = http://www.doom9.org/codecs-quali-105-3.htm | accessdate = 19 December 2007 | deadurl = yes | archiveurl = https://web.archive.org/web/20071231133347/http://www.doom9.org/codecs-quali-105-3.htm | archivedate = 2007年12月31日 }}&amp;lt;/ref&amp;gt;&lt;br /&gt;
&amp;lt;ref&amp;gt;{{cite web | publisher = OSNews | first = Eugenia | last = Loli-Queru | title = Theora vs. h.264 | date = 12 December 2007 | url = http://www.osnews.com/story/19019/Theora-vs-h.264/ | accessdate = 1 April 2008 | archive-date = 2009-02-17 | archive-url = https://web.archive.org/web/20090217222748/http://osnews.com/story/19019/Theora-vs-h.264 | dead-url = no }}&amp;lt;/ref&amp;gt;&lt;br /&gt;
&amp;lt;ref&amp;gt;{{cite web | last = Halbach, Till | title = Dirac and Theora vs. H.264 and Motion JPEG2000 | date = March 2009 | url = http://etill.net/projects/dirac_theora_evaluation/ | accessdate = 22 April 2008 | deadurl = yes | archiveurl = https://archive.today/20120707194336/http://etill.net/projects/dirac_theora_evaluation/ | archivedate = 2012年7月7日 }}&amp;lt;/ref&amp;gt;編碼器在編碼結果上明顯不如同時期的其他編碼器。Google公司的員工Chris DiBona也在2009年宣稱Theora的編碼品質不佳&amp;lt;ref&amp;gt;{{cite mailing list | last = DiBona | first = Chris | title = H.264-in-&amp;lt;video&amp;gt; vs plugin APIs | mailinglist = whatwg | date = 13 June 2009 | url = http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2009-June/020380.html | accessdate = 10 August 2009 | archive-date = 2011-04-27 | archive-url = https://web.archive.org/web/20110427134540/http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2009-June/020380.html | dead-url = no }}&amp;lt;/ref&amp;gt;，為了回應這個論點，Xiph基金會的開發者用Theora 1.1版本的編碼器和[[YouTube]]上的[[H.264]]以及[[H.263|H.263+]]編碼器做比較，結果發現Theora的編碼畫質可以比擬H.264，且更勝於H.263+&amp;lt;ref&amp;gt;{{cite web | last = Maxwell | first = Greg | title = YouTube / Ogg/Theora comparison | publisher = Xiph.Org基金會 | date = 13 June 2009 | url = http://people.xiph.org/~greg/video/ytcompare/comparison.html | accessdate = 10 August 2009 | archive-url = https://web.archive.org/web/20090709062345/http://people.xiph.org//~greg//video//ytcompare//comparison.html | archive-date = 2009-07-09 | dead-url = yes }}&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;{{cite web | last = Maik | first = Merten | title = Another online-video comparison | publisher = Xiph.Org基金會 | date = 15 June 2009 | url = http://people.xiph.org/~maikmerten/youtube/ | accessdate = 10 August 2009 | archive-url = https://web.archive.org/web/20090709062338/http://people.xiph.org//~maikmerten//youtube// | archive-date = 2009-07-09 | dead-url = yes }}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
=== 播放表現 ===&lt;br /&gt;
針對Theora的硬體解碼器，目前有開放原始碼的[[VHDL]]程式正在開發中&amp;lt;ref&amp;gt;{{cite web | url = http://svn.xiph.org/trunk/theora-fpga/ | publisher = Xiph.Org基金會 | title = Xiph Subversion repository: trunk/theora-fpga | accessdate = 2009-08-10 | archive-date = 2009-07-31 | archive-url = https://web.archive.org/web/20090731190443/http://svn.xiph.org/trunk/theora-fpga/ | dead-url = no }}&amp;lt;/ref&amp;gt;。而2006年開始也有針對[[Nios II]]以及[[LEON]]處理器做為解碼器的開發計畫&amp;lt;ref&amp;gt;{{cite web | url = http://wiki.xiph.org/Theora_Hardware | title = XiphWiki: Theora Hardware | accessdate = 10 August 2009 | publisher = Xiph.Org基金會 | archive-date = 2009-09-17 | archive-url = https://web.archive.org/web/20090917120819/http://wiki.xiph.org/Theora_Hardware | dead-url = no }}&amp;lt;/ref&amp;gt;，不過目前並沒有任何可以針對Theora影像做硬體解碼的產品出現在市面上。&lt;br /&gt;
&lt;br /&gt;
== 播放 ==&lt;br /&gt;
&lt;br /&gt;
=== 瀏覽器原生支援 ===&lt;br /&gt;
* [[Firefox|Mozilla Firefox]]在3.5之後的版本&amp;lt;ref name=&amp;quot;gecko191&amp;quot;&amp;gt;{{cite  | title = Firefox3.5/Features  | date = 18 March 2009  | author = MozillaWiki  | publisher = MozillaWiki  | url = https://wiki.mozilla.org/Firefox3.5/Features  | accessdate = 11 October 2009  | archive-date = 2010-07-06  | archive-url = https://web.archive.org/web/20100706104327/https://wiki.mozilla.org/Firefox3.5/Features  | dead-url = no  }}&amp;lt;/ref&amp;gt;&amp;lt;ref name=&amp;quot;firefox35&amp;quot;&amp;gt;{{cite  | title = Mozilla Firefox 3.5 Release Notes  | date = 30 June 2009  | author = Mozilla Corporation  | publisher = Mozilla Corporation  | url = http://www.mozilla.com/en-US/firefox/3.5/releasenotes/  | accessdate = 11 October 2009  | archive-date = 2010-11-30  | archive-url = https://web.archive.org/web/20101130202934/http://www.mozilla.com/en-US/firefox/3.5/releasenotes/  | dead-url = yes  }}&amp;lt;/ref&amp;gt;包括了[[Firefox Mobile]]（Fennec）&amp;lt;ref name=&amp;quot;firefox_mobile&amp;quot;&amp;gt;{{cite | title = Firefox Mobile Features | date = 9 February 2010 | author = Mozilla Corporation | publisher = Mozilla Corporation | url = http://www.mozilla.com/en-US/mobile/features/#cutting-edge | accessdate = 9 February 2010 | archive-date = 2010-12-01 | archive-url = https://web.archive.org/web/20101201024634/http://www.mozilla.com/en-US/mobile/features/#cutting-edge | dead-url = no }}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
* [[Google Chrome]]在3.0.182.2之後的版本&amp;lt;ref name=&amp;quot;chrome3&amp;quot;&amp;gt;{{cite | title = Google Chrome to support HTML 5 video | date = 28 May 2009 | author =  | publisher = SoftSailor | url = http://www.softsailor.com/news/3787-3787.html | accessdate = 11 October 2009 | deadurl = yes | archiveurl = https://web.archive.org/web/20091003194653/http://www.softsailor.com/news/3787-3787.html | archivedate = 2009年10月3日 }}&amp;lt;/ref&amp;gt;&amp;lt;ref name=&amp;quot;chrome3-video-cnet&amp;quot;&amp;gt;{{cite  | title = Google Chrome gets HTML video support  | date = 28 May 2009  | author = Stephen Shankland  | publisher = cnet news  | url = http://news.cnet.com/8301-17939_109-10250958-2.html  | accessdate = 11 October 2009  | archive-date = 2011-07-19  | archive-url = https://web.archive.org/web/20110719142947/http://news.cnet.com/8301-17939_109-10250958-2.html  | dead-url = no  }}&amp;lt;/ref&amp;gt; ，自2009年7月起也包括[[Chromium]]&amp;lt;ref name=&amp;quot;chromium&amp;quot;&amp;gt;{{cite | title = Issue 16657:  Ensure FFmpeg binaries end up in snapshots on all platforms | date = 14 July 2009 | author =  | publisher = google chromium issues list | url = http://code.google.com/p/chromium/issues/detail?id=16657 | accessdate =2010-02-06| archive-date = 2012-11-04 | archive-url = https://web.archive.org/web/20121104222015/http://code.google.com/p/chromium/issues/detail?id=16657 | dead-url = no }}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
* [[SeaMonkey]]在2.0之後的版本&amp;lt;ref name=&amp;quot;seamonkey2&amp;quot;&amp;gt;{{cite  | title = What&amp;#039;s New in SeaMonkey 2.0 Beta 2  | date = 16 September 2009  | author = Robert Kaiser  | publisher = seamonkey-project.org  | url = http://www.seamonkey-project.org/releases/seamonkey2.0b2/changes  | accessdate = 11 October 2009  | archive-date = 2010-06-26  | archive-url = https://web.archive.org/web/20100626224538/http://www.seamonkey-project.org/releases/seamonkey2.0b2/changes  | dead-url = no  }}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
* [[Konqueror]]在4.4.2之後的版本&amp;lt;ref name=&amp;quot;konqueror&amp;quot;&amp;gt;{{cite |title=Bugreport: Wish for audio/video element support in Konqueror |date=13 May 2007 |url=https://bugs.kde.org/show_bug.cgi?id=145380 |accessdate=2 December 2009 |deadurl=yes |archiveurl=https://archive.today/20121228020255/https://bugs.kde.org/show_bug.cgi?id=145380 |archivedate=2012年12月28日 }}&amp;lt;/ref&amp;gt;&amp;lt;ref name=&amp;quot;konqueror44&amp;quot;&amp;gt;{{cite |title=Plans for Konqueror 4.4 |date=26 November 2009 |url=http://forum.kde.org/viewtopic.php?f=18&amp;amp;t=83851 |accessdate=2 December 2009 |archive-date=2011-07-17 |archive-url=https://web.archive.org/web/20110717175111/http://forum.kde.org/viewtopic.php?f=18&amp;amp;t=83851 |dead-url=no }}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
* [[Opera (瀏覽器)|Opera]]在10.50之後的版本&amp;lt;ref&amp;gt;{{cite web |url=http://my.opera.com/core/blog/2009/12/31/re-introducing-video |title=(re-)Introducing &amp;lt;video&amp;gt; - Official blog for Core developers at Opera |author=Philip Jägenstedt |publisher=Opera |date=2009-12-31 |accessdate=2010-01-02 |archiveurl=https://web.archive.org/web/20100104205648/http://my.opera.com/core/blog/2009/12/31/re-introducing-video |archivedate=2010-01-04 |deadurl=yes }}&amp;lt;/ref&amp;gt;&amp;lt;ref&amp;gt;{{cite web |url=http://my.opera.com/desktopteam/blog/happy-new-year |title=Happy New Year! - Official blog for Core developers at Opera |author=Arjan van Leeuwen |publisher=Opera |date=2009-12-31 |accessdate=2010-01-02 |archiveurl=https://web.archive.org/web/20100104201911/http://my.opera.com/desktopteam/blog/happy-new-year |archivedate=2010-01-04 |deadurl=yes }}&amp;lt;/ref&amp;gt;，在Opera 9.5的實驗版本中也有支援&amp;lt;ref name=&amp;quot;opera&amp;quot;&amp;gt;{{cite | title = Experimental Opera-video build with native Ogg Theora support | date = 25 April 2007 | author =  | publisher = Opera | url = http://my.opera.com/ResearchWizard/blog/experimental-opera-video-build-with-native-ogg-theora-support | accessdate = 11 October 2009 | archive-date = 2007-12-02 | archive-url = https://web.archive.org/web/20071202032052/http://my.opera.com/ResearchWizard/blog/experimental-opera-video-build-with-native-ogg-theora-support | dead-url = yes }}&amp;lt;/ref&amp;gt;&amp;lt;ref name=&amp;quot;opera-dev&amp;quot;&amp;gt;{{cite | title = A call for video on the web - Opera &amp;lt;video&amp;gt; release on Labs | date = 7 November 2007 | author =  | publisher = Opera | url = http://dev.opera.com/articles/view/a-call-for-video-on-the-web-opera-vid/ | accessdate = 11 October 2009 | archive-date = 2010-10-22 | archive-url = https://web.archive.org/web/20101022140811/http://dev.opera.com/articles/view/a-call-for-video-on-the-web-opera-vid/ | dead-url = no }}&amp;lt;/ref&amp;gt;。&lt;br /&gt;
&lt;br /&gt;
=== 瀏覽器外掛程式（Plug-in）===&lt;br /&gt;
可以透過下列的[[外掛程式]]讓瀏覽器播放Theora影像&lt;br /&gt;
&lt;br /&gt;
* [[Annodex]]的外掛程式（透過[http://wiki.xiph.org/index.php/OggPlay OggPlay]{{Wayback|url=http://wiki.xiph.org/index.php/OggPlay |date=20090228201554 }}）&lt;br /&gt;
* [[Cortado (software)|Cortado]]，一個以[[Java|Java語言]]開發的播放器應用程式（applet）&lt;br /&gt;
* [[VLC media player|VLC媒體播放器]]針對IE以及Firefox的瀏覽器外掛程式&lt;br /&gt;
&lt;br /&gt;
=== 支援的應用程式 ===&lt;br /&gt;
&lt;br /&gt;
* [[FFmpeg]]（有自己的实现）&lt;br /&gt;
* [[Helix project|Helix Player]]&lt;br /&gt;
* [[Miro Media Player]]（舊名Democracy Player）&lt;br /&gt;
* [[MPlayer]]以及其前端程式&lt;br /&gt;
* [[Songbird]]、[[Totem]]、[[Moovida]]和所有以[[GStreamer]]為基礎的播放器&lt;br /&gt;
* [[VLC media player|VLC]]（原生支援）&lt;br /&gt;
* [[xine]]和以libxine為基礎的播放器，像是[[Kaffeine]]&lt;br /&gt;
* [[Dragon Player]]和所有以[[Phonon (KDE)|Phonon]]為基礎的播放器&lt;br /&gt;
&lt;br /&gt;
== 參見 ==&lt;br /&gt;
* [[Ogg]]&lt;br /&gt;
* [[WebM]]&lt;br /&gt;
&lt;br /&gt;
== 参考资料 ==&lt;br /&gt;
{{refs|2}}&lt;br /&gt;
{{多媒體壓縮格式}}&lt;br /&gt;
{{Compression Software Implementations}}&lt;br /&gt;
&lt;br /&gt;
[[Category:使用BSD許可證的軟體]]&lt;br /&gt;
[[Category:视频编解码器]]&lt;/div&gt;</summary>
		<author><name>imported&gt;Ottokang</name></author>
	</entry>
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