SWF

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Adobe Flash (SWF)
Flash file Icon
Filename extension .swf
Internet media type application/x-shockwave-flash
Developed by FutureWave Software,
later taken over by Macromedia and
Adobe Systems
Type of format Vector graphic animation

The file format[1] SWF (stands for "Shockwave Flash" and not for "Small Web Format" as often wrongly assumed, [2] pronounced swiff[3]) a partially open repository for multimedia and especially for vector graphics, originated with FutureWave Software and has come under the control of Adobe. Intended to be small enough for publication on the web, SWF files can contain animations or applets of varying degrees of interactivity and function.

SWF currently functions as the dominant format for displaying "animated" vector graphics on the Web, far exceeding the use of the W3C open-standard SVG, which has met with problems over competing implementations.

SWF files can be generated from: SwishMax2 (8 levels) and also within Adobe Flash and Adobe Flex Builder, as well as through MXMLC, Adobe's command line application compiler which is part of the freely available Flex SDK. Open source compilers also exist such as Motion-Twin ActionScript 2 Compiler (MTASC).

Contents

[edit] History

FutureWave Software, a small company later acquired by Macromedia, originally defined the file format with one primary objective: to create small files for displaying entertaining animations.[4] The idea was to have a format which could be reused by a player running on any system and which would work with slower network connection.

Adobe acquired Macromedia in 2005.

On May 1, 2008, Adobe dropped its licensing restrictions on the SWF format specifications, as part of the Open Screen Project. However, Rob Savoye, a member of the Gnash development team, has pointed to some parts of the Flash format which remain closed.[5] On July 1, 2008, Adobe released code which allowed the Google and Yahoo search-engines to crawl and index SWF files.[6]

[edit] Description

Originally limited to presenting vector-based objects and images in a simple sequential manner, the format in its newer[when?] versions allows audio, video and many different possible forms of interaction with the end-user. Once created, SWF files can be played by the Adobe Flash Player, working either as a browser plugin or as a standalone player. SWF files can also be encapsulated with the player, creating a self-running SWF movie called a "projector".

Adobe makes available plugins to play SWF files in web browsers on many desktop operating systems, including Microsoft Windows, Apple Mac, and Linux on the x86 architecture. As of 2007 intensive development had taken place on Gnash, a free-software implementation of a SWF player. Another FOSS implementation is swfdec.

Based on an independent study conducted by Millward Brown, over 99% of Web users now have an SWF plugin installed, with around 90% having the latest version of the Flash Player.[7] Sony PlayStation Portable consoles can play limited SWF files in Sony's web browser, beginning with firmware version 2.71. Both the Nintendo Wii [8] and the Sony PS3 [9] consoles can run SWF files through their Internet browsers.

[edit] Licensing

Adobe makes available a partial specification of SWF. The document is missing "huge amounts" of information needed to completely implement SWF, omitting specifications for RTMP and Sorenson Spark.[10] Until May 1, 2008, implementing software that plays the format was disallowed by the specification's license.[11] On that date, as part of its Open Screen Project, Adobe dropped all such restrictions on the SWF and FLV formats.[12] However, the SWF specification was released under a very restrictive license:[13]

This manual may not be copied, photocopied, reproduced, translated, or converted to any electronic or machine-readable form in whole or in part without written approval from Adobe Systems Incorporated.

As a result, coordinating with developers of an SWF implementation is difficult because the document cannot be easily shared.

Implementing software which creates SWF files has always been permitted, on the condition that the resulting files render "error free in the latest publicly available version of Adobe Flash Player."[14]

GNU has started developing a free software SWF player called Gnash under the GNU General Public License (GPL). Another player is the GNU LGPL swfdec.

[edit] See also

[edit] References

  1. ^ Open Screen Project
  2. ^ [1], Author of the Flash 2 Manual
  3. ^ See the specification of SWFv9 in PDF at http://www.adobe.com/devnet/swf/
  4. ^ "The History of Flash: The Dawn of Web Animation". Adobe Systems. http://www.adobe.com/macromedia/events/john_gay/page04.html. Retrieved on 2008-01-21. 
  5. ^ Free Flash community reacts to Adobe Open Screen Project
  6. ^ Streamingmedia.com: Google and Yahoo Roll out Flash Search
  7. ^ "Flash Player Penetration: Flash content reaches over 98 percent of Internet viewers". Adobe Systems. http://www.adobe.com/software/player_census/flashplayer/. Retrieved on 2008-01-21. 
  8. ^ "Wii Internet Channel". http://www.nintendo.com/wii/channels/internetchannel. 
  9. ^ Eric Lempel. "PS3 Firmware (v2.53) Update". Playstation.Blog. http://blog.us.playstation.com/2008/12/01/ps3-firmware-v253-update. Retrieved on 2009-03-12. 
  10. ^ "Free Flash community reacts to Adobe Open Screen Project". http://www.openmedianow.org/?q=node/21. Retrieved on 2008-11-29. 
  11. ^ "SWF and FLV File Format Specification License Agreement". Adobe Systems. 2007-06-27. http://www.adobe.com/licensing/developer/fileformat/license/. Retrieved on 2008-01-05. "You may not use the Specification in any way to create or develop a runtime, client, player, executable or other program that reads or renders SWF files." 
  12. ^ "Open Screen Project Press Release". Adobe Systems. 2008-05-01. http://www.adobe.com/aboutadobe/pressroom/pressreleases/200804/050108AdobeOSP.html. Retrieved on 2008-05-01. 
  13. ^ "SWF File Format Specification Version 10". http://www.adobe.com/devnet/swf/pdf/swf_file_format_spec_v10.pdf. Retrieved on 2008-11-29. 
  14. ^ "Adobe Player Licensing: Flash Player Developer SDKs". Adobe Systems. http://www.adobe.com/licensing/developer. Retrieved on 2008-01-21. 

[edit] External links

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