Multimedia Plug-in Content Standards (Flash, Shockwave etc.) v1.14

1. When should plug-in content be used?

1.1. Plug-ins to extend the experience

1.1.1. Multimedia plug-in content SHOULD only be used to extend the user experience of sites on bbc.co.uk, to raise their overall appeal, or to promote the brand.

1.1.2. If a user does not have the correct plug-in to access the enhanced content, or cannot easily access the content because they are using assistive technologies (such as screen readers) or Betsie to view the site, this should not detract from the user accessing the core content of the website.

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2. Approved plug-in formats and when to use each one

2.1. Approved formats

2.1.1. You MUST only use the following formats:

2.1.1.1. Flash

2.1.1.1.1. Any projects proposing to use streamed Flash Video MUST gain prior permission from the Editor, NM Standards & Guidelines – see section 3.6.

2.1.1.2. Shockwave

2.1.1.3. Java

2.1.1.4. iPIX, QuickTime VR

2.1.1.5. PDFs MAY be used in cases where print integrity is essential and when content needs to be in a downloadable format.

2.1.1.6. Approved AV formats (such as Real and Windows Media) can be found in the AV Streaming Standards.

2.1.2. If you need to use any other plug-in formats, you MUST contact the Editor, NM Standards & Guidelines with a business case for the use of that format to gain an exception.

2.2. How to choose the format

2.2.1. You SHOULD choose the format to achieve the broadest audience reach. Hence:

2.2.1.1. Flash MUST NOT be used if you can reasonably achieve the same results with animated GIFs, Cascading Style Sheets and/or DHTML.

2.2.1.2. Flash SHOULD NOT be used until you have assessed the trade-off between the user possibly not having the correct version of the plug-in (or the plug-in at all), the size and complexity of what the content is to achieve, and its respective costs.

2.2.1.3. Flash video MUST NOT be used if you can reasonably achieve the same interactive functionality with Real or Windows video in combination with DHTML.

2.2.1.4. Director MUST NOT be used if you can provide the functionality/experience that your application/prototype requires using Flash. Director MAY be used if you need to make use of Director's high-level programming language features or an existing Director plug-in/Xtra.

2.2.1.5. You MUST NOT publish content for any plug-ins while they remain in Alpha or Beta release status.

2.3. Development of Flash content

2.3.1. If developing content in Flash, you MUST comply with the Flash Accessibility Standards.

2.3.2. You MUST choose the plug-in version that is developed for according to a balance of:

2.3.2.1. functionality/cost of production vs. penetration rate

2.3.2.1.1. Penetration rate can be assessed from Macromedia's figures at http://www.macromedia.com/software/player_census/flashplayer/
version_penetration.html or IF&L's figures at http://technet.wc.bbc.co.uk/stats/cs/ [ internal BBC doc – gain access via your Technical Account Manager].

2.3.2.1.2. The aims of each project and target audience should determine the plug-in version selected. In general:

2.3.2.1.2.1. Flash files SHOULD be created in v5, v6, v7 or v8 formats as these versions are included in most browsers and platforms and provide additional developmental benefits in each iteration.

2.3.2.1.2.2. Within this range of Flash revisions, you MUST consider the following:

• Flash v4 format SHOULD NOT be used unless the target audience is understood to be using that specific plug-in (v4 content contains deprecated ActionScript that may not always work in the latest versions of the Flash plug-in).
• Flash v7 and upwards MUST make best use of all the accessibility functionality introduced in those versions, UNLESS you have produced and linked to alternative versions (see Section 3.1) For details, see: Macromedia/Accessibility and Macromedia Flash MX 2004 or Best Practice for Accessible Flash Design.
• Flash v8 format will exclude Linux users (as at time of writing there is no Flash 8 player available for that platform).

2.3.2.2. Functionality/cost of production of Flash content

Some projects may require functionality which is seemingly only available in a later version of the Flash plug-in, but before settling on a version you should first determine if producing a similarly-performing .flv in a lower player version is technically feasible within time constraints.

2.3.2.3. Reach/stability of Flash player

Reach/stability of the Flash player can be discovered in the following ways:

2.3.2.3.1. Target Audience for content

Whether or not the specific main target audience for your site is likely to have that version of the Flash player - based on our best Flash player penetration statistics gathered from that audience (e.g. education, kids).

2.3.2.3.2. Current bbc.co.uk Audience

Whether or not our current audience is likely to have that version of the Flash player - also considering whether or not the player is included with the browsers our audience currently use (see Macromedia's distribution partners link).

2.3.2.3.3. Potential bbc.co.uk Audience

Whether or not our potential audience is likely to have that version of the Flash player - based on our own records (IE-only link) [ internal BBC doc – gain access via your Technical Account Manager], and data from Macromedia's penetration of plug-in versions at Macromedia/Flash Player Version Penetration (choose the regional stats closest to your target audience).

2.4. Development of PDF content

2.4.1. If developing PDF content, you MUST comply with the PDF Accessibility Standards.

2.5. Development of Shockwave content

2.5.1. If developing content in Director, you MUST take full advantage of accessibility features where available.

2.5.2. For more on Director accessibility, see: http://www.macromedia.com/macromedia/accessibility/features/director/

2.6. Development of Java content

The development of Java-based content SHOULD be carefully assessed with respect to the Total Cost of Ownership and usability issues. It has behaved inconsistently within browsers in the past (especially in pre-OS X Mac browsers), and may present security pop-ups to certain users. Traditional uses of the technology (i.e. the creation of news tickers) can be achieved in JavaScript or Flash, and these SHOULD be used due to their lower user system/security requirements.

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3. General considerations for use of plug-in content

3.1. The following standards and guidelines apply to all approved multimedia plug-in formats.

3.1.1. Provide an alternative to plug-in content

3.1.1.1. For core content presented using a plugin, you MUST provide alternative content, for non-core content you SHOULD provide alternative content, where technically feasible. This helps those users without the plug-in or who find plug-in content difficult to browse using assistive technologies (such as screen readers).

3.1.1.2. Alternatives to multimedia content MUST convey equivalent content or learning outcomes as the multimedia content as far as is viable.

3.1.1.3. Alternative content may include:

3.1.1.3.1. A similar looking, but less-dynamic flat HTML presentation, using static or animated GIFs and/or DHTML content, for those without Flash

3.1.1.3.2. A worksheet or quiz to convey the same content or learning outcome in a text form, for screen reader users (see, for example, the quizzes at bbc.co.uk/schools/scienceclips/)

3.1.1.3.3. If you are not going to provide an alternative version you MUST provide informative alt-text descriptors for all multimedia content (see Textual Equivalents Standards)

3.1.1.3.4. For core content where alternative content is available there MUST be a HTML link to allow the user to switch between the versions.

3.1.2. Alternative Sites

3.1.2.1. In cases where a site uses plug-in content to deliver the core content of the site and alternative content cannot be adequately provided by detection scripts, an HTML version of the site SHOULD be created.

3.1.2.2. The HTML version of the site MUST be maintained in synchronisation with the multimedia-enhanced site. A common way of doing this is to keep the content of the site in XML and produce Flash and non-Flash versions from this content whenever it is updated.

3.2. Embedding plug-in content into pages

3.2.1. Embedding Flash content

3.2.1.1. If you are embedding Flash content into a page you MUST use the BBC JavaScript Tools Plugins Module [ internal BBC doc – gain access via your Technical Account Manager]

3.2.1.2. Macromedia's own Express Install method MAY be used in conjunction with this (especially if your Flash content is to be published for version 6,0,65 and upward.

3.2.2. Embedding other plug-in content

3.2.2.1. Shockwave and AV content SHOULD be embedded using standard scripts. See, for example, the embed tools available from Embedding Multimedia (on Intracat) [ internal BBC doc – gain access via your Technical Account Manager].

3.2.3. Broadband Real and Windows Media content MUST be embedded using the Media Selector or the Media Wrapper (see Media Wrapper/Selector article on Intracat ).

3.2.4. PDF content MUST be linked to with an indication that the link is to an Adobe Acrobat document and not a standard web page, so not to confuse users if/when the Acrobat application menu appears within the browser window.

3.3. Tell the user how to get the plug-in player

3.3.1. All pages using plug-in content MUST display a link to the plug-in's BBC WebWise page, where one is available, to provide instructions and links on how to download the free player. You MUST NOT link directly to the plug-in download.

3.3.2. You can find a list of the relevant links on WebWise.

3.3.3. Pages whose target audience is children or their parents, should use the WebWise pages which have been specially created to be understood by children at: http://www.bbc.co.uk/cbbc/help/downloads.shtml.

3.3.4. Pages written in a language other than English should display a link to the plug-in help page written in that language.

3.3.5. It should be noted that the Express Install method of Flash plug-in upgrade can potentially get round previous problems of user player upgrade (involving firewalls, etc).

3.4. Download size, optimising and pre-loaders

3.4.1. Web pages which include embedded plug-in content MUST comply with the requirements of the Download Standards.

3.4.2. Accordingly, all Flash/Shockwave applications MUST be optimised for download speed. You can find an evolving library of hints and tips for optimising plug-in content, and details of how to submit your own contributions, at BBC Hints and Tips for Optimising Download Size of a Page [ internal BBC doc – gain access via your Technical Account Manager].

3.4.3. All plug-in content over an initial 70kB MUST provide feedback to users showing how much content a user has yet to download or what percentage of the total content has been loaded, to indicate how long they might expect to wait for the content to complete loading.

3.4.4. You SHOULD stream the loading of Flash content in the background while users are interacting with earlier content to minimise perceived loading time. For example, level two of a game could load in the background while the user is playing level one.

3.5. Testing of plug-in content

3.5.1. Functionality testing (against different versions of the Flash player)

3.5.1.1. All plug-in content MUST be tested (detect script and flash functionality) against:

3.5.1.2. The latest minor version of the Flash player you're developing for, on all supported platforms and browsers.

3.5.1.3. See the Browser Support Standards for a list of supported browsers.

3.5.1.4. You MUST also test your content against minor versions of the v4, 5, 6, 7 and 8 Flash players (on different platforms) which have identified problems with particular functionalities that your content uses (see The Adobe Flash release notes).

3.5.1.5. For testing purposes, Adobe provides a host of uninstallers and test Flash plug-ins, available from Macromedia/Flash TechNote/Archived Macromedia Flash Players available for testing purposes and Macromedia/Flash TechNote/Archived Macromedia Flash Player minor versions available for testing.

3.5.1.6. If your content identifies a bug in a particular minor version of the Flash player, you MUST fix it with a workaround or configure the content's detect script to redirect users to the alternative content when they have the player in question.

3.5.2. Security testing

3.5.2.1. All plug-in content MUST be secure as well as functional. (Developers MUST NOT pull in any text or any other data from sites external to the BBC unless authorised by the Editor, NM Standards & Guidelines and the BBC Information Security Officer. Additionally, plug-in applications MUST adhere to the Application Development Standards.

3.5.3. Performance testing

3.5.3.1. All plug-in content MUST be optimised to ensure a good user experience, and especially for screen reader users whose computers may crash if overloaded by an inefficient Flash animation.

3.5.3.2. It should be noted that pre-Flash 8, Flash content habitually played slower on Mac platforms than Windows (this is a known issue). If you need to ensure uniform performance on the Mac then Flash 8 should be carefully considered, but weighted-against the probable lower Flash Player penetration rate (when compared to the number with Flash 4/5/6/7-capable players).

3.6. Standards for use of Flash Video

3.6.1. Please refer to the AV Standards for further requirements for the use of Flash video.

3.6.2. Flash Video MUST NOT be used unless the video is part of other interactive Flash content, within a larger web page which involves interactivity (preferably with the video content itself), or where the video is to be under or overlaid with other Flash or HTML content.

3.6.3. You MUST NOT serve broadband video content to non-U.K. IP addresses. These can be detected for using the GeoIP Apache module (http://braeburn.tv.bbc.co.uk/confluence/display/Infra/GeoIpUsage [ internal BBC doc – gain access via your Technical Account Manager]).

3.6.4. You MUST contact the New Media Technical Architect to discuss infrastructure support for any Flash Video files before uploading the files. You will need to provide the following information:

• The download size of the Flash Video files
• How long they are to be live on bbc.co.uk servers
• Estimated number of requests and concurrent requests to download the Flash Video files

3.6.5. If a single .flv file exceeds 500kB, or the range of .flv files on your site exceeds 1GB, then they MUST be hosted on downloads.bbc.co.uk.

3.6.6. Flash 8 offers significant video file size benefits that should be considered if your overall Flash content is video-heavy. However, weigh this against the lower percentage of users with that version of the player.

3.6.7. Flash Video delivery

3.6.7.1. You MAY make use of downloaded or progressively downloaded Flash Video, but you MUST NOT use Flash Video Streaming (as it is not currently supported by the bbc.co.uk technical infrastructure).

3.6.7.2. If you feel you have a good business case for a project involving Flash Video Streaming you MUST contact the chair of the Streaming Strategy Group before proceeding with the project.

3.6.8. Flash Video format

3.6.8.1. If your project uses Flash v7 or higher, you SHOULD use .flv format, as it uses a more efficient codec than .swf. .flv files can be progressively downloaded in Flash v7 and above.

3.6.8.2. For any video clips of longer than 120 seconds, you MUST use .flv format (to prevent audio-synch problems). Hence all .swf video clips MUST be less than 120 seconds long.

3.6.8.3. For more information, see Macromedia/Flash Article/Flash Learner's Guide: Delivery Options for Flash Video.

3.6.9. Frame rates, clip length of progressively-downloaded .flv video

3.6.9.1. Whereas for Real and Windows Media video we have specific standards for frame rates and window size, the editorial propositions for using Flash are so varied that you MAY choose whatever video duration and window size you wish to use, according to your editorial proposition. The only limitations are those set by the file size of the resulting Flash Video file and bitrate.

3.6.9.2. Frame rates MUST adhere to the Flicker guidelines.

3.6.10. File size of Flash Video

3.6.10.1. You MUST ensure that the file size of your video file is as small as you can make it while satisfying the editorial requirements. This will decrease the length of time the user will need to wait before the video starts playing, and the amount of disk storage used by the clip on bbc.co.uk servers.

3.6.10.2. You SHOULD split downloaded video files (i.e. not streamed or progressively downloaded) into separate files, to counter these concerns. Wherever possible, you SHOULD also load the video files in the background while users are interacting with earlier content, to minimise perceived loading time.

3.6.10.3. If using Flash v7 or higher, you MAY use Progressive Download to let the video start playing earlier than it would for normal Download.

3.6.11. Bitrate of Flash Video

3.6.11.1. All Flash video MUST adhere to the guidelines set out by the Audio-Video Standards; 256kbps remains the maximum data rate. Setting higher bitrates will likely:

• impact on the buffering times a user experiences when viewing the content.
• increase the filesize of the .flv
• may lead users with older machines to experience difficulties in playing back the content (as higher bitrates require more processing power on an end-user's machine).

3.6.11.2. Permission for using higher-bitrate video MUST be sought from the Streaming Strategy Group.

3.6.11.3. If bitrate is likely to be of primary concern to the editorial proposition then Flash 8 video should be considered as it provides significant quality improvements over Flash 7-equivalent bitrates.

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4. Triggers for updates of this document

4.1. A Flash 8 version of Linux may be released around the time of this document being published, in which case this needs to be reviewed.

4.2. Revisions to the AV Standard require the group to revisit Section 4.

4.3. The stability of different plug-in versions included in this document will be reviewed by the NM Plug-Ins Working Group twice a year.

4.4. Future versions of these standards should include:

4.4.1. More specific info on performance testing - processor load etc.

4.4.2. More specific information about how to embed Flash on pages.

4.4.3. More detailed standards for the production of Shockwave, Java (v1.1 at present; should v2.0 be developed for?), IPIX/QuickTime VR (panoramas), and SMIL content.

4.4.4. Specific information on the production of screensavers and games.

4.4.5. More information on usability, accessibility of Flash files (MX 2004 onwards), and reuse of plug-in content (examples from current trial projects of making our Flash content accessible - e.g. Team Selector).

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5. Document history

Date	Version	Change	Author
15/11/2007	v1.14	Updated to refer to the new Flash Accessibility and PDF Accessibility standards	Jonathan Hassell
15/03/2006	v1.13	Changes by Technical Forum	Tred Magill
09/03/2006	v1.12	Changes made to source code requirements section (removed) and video bitrates. Minor wording amends.	Wayne McManus
28/02/2006	v1.11	Comments/amends approved and/or deleted. Format clean-up. Hyperlinks added where relevant.	Wayne McManus
21/02/2006	v1.10	Tech forum amends, source file recommendations, core content defined	Wayne McManus Plug-Ins WG
24/01/2006	v1.09	Tech forum amends, recommendations	Wayne McManus
15/11/2005	v1.08	Major revisions including recommendations on use of Flash 8	Plug-Ins WG Tred Magill
16/03/2005	v1.07	After amendments required by Tech Forum on 14/03/2005	Jonathan Hassell
10/03/2005	v1.06	Updates after email review comments from Working Group	Jonathan Hassell
04/03/2005	v1.05	Added in section on Flash Video (in yellow )	Jonathan Hassell
04/03/2005	v1.04	Added in screensavers and panoramas stuff from ch4 of Web Dev Guidelines (in blue )	Jonathan Hassell
03/12/2004	v1.03	Alterations required for approval by Tech Forum on 03/12/2004	Jonathan Hassell
30/11/2004	v1.02	Slight updates to proposed updates after Plug-Ins WG meeting on 29/11/2004 - allow v7, clarification of alternatives, note re Flash video, performance testing	Plug-Ins WG
19/11/2004	v1.01	Proposed updates after accessibility/v7 meeting with Macromedia	Jonathan Hassell
04/03/2004	v1.00	Standard renumbered as v1.00 on approval by Standards Exec	Jonathan Hassell
11/02/2004	v0.73	Another clarification in 3.6	Jonathan Hassell
05/02/2004	v0.72	One final change in wording in 3.1.1 for clarity	Jonathan Hassell
29/01/2004	v0.71	Updates required by Tech Forum for approval of the standard	Jonathan Hassell
26/01/2004	v0.70	Updated links to embed scripts	Jonathan Hassell
22/01/2004	v0.69	Revisions from Working Group emails - inclusion of QuickTime for panoramas	Jonathan Hassell
21/01/2004	v0.68	Revisions from Gemma Garmeson and Mat Hampson (regarding Real Media)	Jonathan Hassell
08/01/2004	v0.67	Link added to find minor versions of Flash players	Adam Rees, Jonathan Hassell
08/01/2004	v0.66	Required edits after meeting - URL of approved scripts area etc.	Jonathan Hassell
07/01/2004	v0.65	Edits from WG meeting on 07/01/2004 (still a few more rewords and highlighted info to do before presentation to Tech Forum)	Plug-Ins Working Group
22/12/2003	v0.64	Tidying removed info into a 2nd doc and web pages; minor re-edits; to be discussed in next group meeting	Jonathan Hassell
22/12/2003	v0.63	Additions and edits	Wayne McManus, Jonathan Hassell
02/12/2003	v0.62	Additions and edits; to be discussed in next group meeting.	Wayne McManus
13/08/2003	v0.61	Minor edits - corrected section numbering	Jonathan Hassel
12/08/2003	v0.6	JH edits of combined sections - now needs a discussion of many elements of this by the WG	Jonathan Hassell
06/08/2003	v0.5	More combining of the sections	Jonathan Hassell
05/08/2003	v0.4	Combining the sections	Jonathan Hassell
01/08/2003	v0.3	More edits by JH - now includes all useful info from Web Dev Guidelines	Jonathan Hassell
29/07/2003	v0.2	JH and WM checking against what's in the other documents...	Wayne McManus , Jonathan Hassell
03/06/2003	v0.1	Jonathan created doc from Wayne M's draft doc	Wayne McManus , Jonathan Hassell

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