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Flash Video is a container file format used to deliver video over the Internet using Adobe Flash Player version 6 and newer. Flash Video content may also be embedded within SWF files. There are two different video file formats known as Flash Video: FLV and F4V. The audio and video data within FLV files are encoded in the same manner as they are within SWF files. The F4V file format is based on the ISO base media file format and is starting with Flash Player 9 update 3.〔 Both formats are supported in Adobe Flash Player and developed by Adobe Systems. FLV was originally developed by Macromedia. Flash Video is the ''de facto'' standard for web-based streaming video (over RTMP). Notable users of it include YouTube, Hulu, VEVO, Yahoo! Video, metacafe, Reuters.com, and many other news providers. Flash Video FLV files usually contain material encoded with codecs following the Sorenson Spark or VP6 video compression formats. The most recent public releases of Flash Player (collaboration between Adobe Systems and MainConcept) also support H.264 video and HE-AAC audio.〔(【引用サイトリンク】 publisher = MainConcept )〕 All of these compression formats are restricted by patents. Flash Video is viewable on most operating systems via the Adobe Flash Player and web browser plugin or one of several third-party programs. Apple's iOS devices do not support the Flash Player plugin and so require other delivery methods such as provided by the Adobe Flash Media Server.〔(Adobe Flash Media Server )〕 == History == Support for video in SWF file format was added in Flash Player 6, released in 2002. In 2003, Flash Player 7 added direct support for FLV file format. Because of restrictions in the FLV file format, Adobe Systems has created in 2007 new file formats listed below, based on the ISO base media file format (MPEG-4 Part 12). Flash Player does not check the extension of the file, but rather looks inside the file to detect which format it is.〔〔Kaourantin.net (31 October 2007) Tinic Uro (New File Extensions and MIME Types ), Retrieved on 2009-08-03〕 The new file formats are completely different from the older FLV file format. For example, F4V does not support Screen video, Sorenson Spark, VP6 video compression formats and ADPCM, Nellymoser audio compression formats.〔〔 Authors of Flash Player strongly encourage everyone to embrace the new standard file format F4V (ISO base media file format). There are functional limits with the FLV structure when streaming H.264 or AAC which could not be overcome without a redesign of the file format. This is one reason why Adobe Systems is moving away from the traditional FLV file structure.〔 Initial format since 2002 is ''Flash Video'', file suffix is ''.flv'' with a MIME derived Internet media type of ''video/x-flv''. Extended from 2007 to support the ''ISO base media file format'', Adobe branded file suffix is ''.f4v'' with the same MIME derived Internet media type of ''video/mp4'' as the Apple file suffix of ''.m4v'' and the general file suffix of ''.mp4''. Adobe branded file suffixes exist for ''.f4p'' which relates to media encrypted with their ''Adobe Access'' DRM scheme with ''.f4a'' and ''.f4b'' which relate respectively to ''.m4a'' and ''.m4b'' with the same MIME derived Internet media type of ''audio/mp4''. SWF files published for Flash Player 6 and later versions are able to exchange audio, video, and data over RTMP connections with the Adobe Flash Media Server. One way to feed data to Flash Media Server is from files in the FLV file format. Starting with SWF files created for Flash Player 7, Flash Player can play FLV file format directly (MIME type video/x-flv). Starting with SWF files created for Flash Player 9 Update 3, Flash Player can also play the new F4V file format.〔 Use of the H.264 and AAC compression formats in the FLV file format has some limitations and authors of Flash Player strongly encourage everyone to embrace the new standard F4V file format.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Flash Video」の詳細全文を読む スポンサード リンク
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