This week’s DLTJ Thursday Threads has just two pointers. First, a new volunteer web service to report problems with websites, which may be useful for not only our own sites but for the sites our patrons visit. Second, a nine-minute video that illustrates the reuse of themes and ideas in motion pictures across time.

If you find these threads interesting and useful, you might want to add the Thursday Threads RSS Feed to your feed reader or subscribe to e-mail delivery using the form to the right. If you would like a more raw and immediate version of these types of stories, watch my FriendFeed stream (or subscribe to its feed in your feed reader). Comments and tips, as always, are welcome.

Addressing Accessibility, from Fix the Web

Web accessibility is not improving very quickly despite the efforts of many experts. The scale of the problem is huge and there is a need for culture change amongst web developers and website owners.

Our solution is to make it super easy for disabled and older people to report problems with websites. Volunteers do the work of contacting the website owners and signposting them to support. In doing this work, volunteers will understand more about e-accessibility for themselves, as well as giving crucial information to website owners. Everybody wins!

Details of how the process works are explained for the different roles (volunteering and issue reporter) and in the FAQs.

You can get involved in three different ways:

1. Report issues you are having with websites.
2. Volunteer to help liaise with website owners.
3. Support the development of the project: contact the coordinator.

This project intersects with libraries in two ways. First, we must make sure our websites are available to all populations — including users browsing the web with alternate (large screen, color neutral, and/or audio-driven) browsers. (If this intersection is of interest to you, then check out the 1-hour webinar from Infopeople on an ADA Update: Revised Regulations for Disability Accommodations for the Public.) The second place it might intersect with libraries is assisting patrons browsing the web. Although reporting a site won’t fix it for that patron, if it is a common site for your patrons then reporting the issue will engage a group of volunteers that can help site owners fix the accessibility problems.

Everything is a Remix Part 2

An exploration of the remix techniques involved in producing films. Part Two of a four-part series.

Where did George Lucas get ideas for Star Wars? Watch this 9 minute video that shows side-by-side comparisons of Star Wars with movies that the creator of this video says were Lucas’ sources. The creator also describes other examples of ideas and images are drawn through film. This video is the second part (and latest available) of an eventual four-part series. [Via Ron Murray]

The text was modified to remove a link to http://www.fixtheweb.net/more-about-being-volunteer on June 9th, 2011.

This week Amazon takes center stage of DLTJ Thursday Threads with a report of their new Kindle Singles program for medium-form digital content and a screen-reader-aware version of the Kindle reader application for PCs. After that is a look at how scholarly discourse is changing — radically! — with the availability and use of near-real-time feedback loops. And we close out with a peek at shaky ground in the world of ISBN identifiers.

As a sidenote to last week’s comment about this blog migrating to Amazon’s service…there are still a few hiccups. For instance, last week’s edition of DLTJ Thursday Threads wasn’t published via the RSS feed until late in the day and it wasn’t until Friday that the e-mail subscribers received it. I think those issues are ironed out now, but if you notice any other problems please let me know.

Kindle Singles — Compelling Ideas Expressed at Their Natural Length — Now Available in the Kindle Store

Before the advent of digital reading, writers often had to choose between making their work short enough for a magazine article or long enough to deliver the “heft” required for book marketing and distribution. Three months ago, Amazon made a call to serious writers, thinkers, scientists, business leaders, historians, politicians and publishers to join Kindle in making a new kind of content available to readers—Kindle Singles. Typically between 5,000 and 30,000 words, each Kindle Single is intended to allow a single killer idea — well researched, well argued and well illustrated — to be expressed at its natural length. Today, Amazon is introducing the first set of Kindle Singles to the Kindle Store. …

The new Kindle Singles section of the Kindle Store is now available at www.amazon.com/kindlesingles. Available to both Kindle device and app users, and priced between $0.99 and $4.99, the first set of Kindle Singles include original reporting, essays, memoirs and fiction. Amazon plans to frequently launch many more Kindle Singles over time.

Is there room for commercial content between “short enough for a magazine article” and a full-fledged book? Amazon seems to think so with this announcement of the Kindle Singles program. Among the first are three works from TEDTalk speakers priced at $2.99 each. The content is only available in digital form and only in the proprietary Kindle format. This may be a problem for a library trying to acquire this content for its collection (although this is just a subset of the more general issue of acquiring content saddled in proprietary formats with restrictive digital rights management). What makes this problem more acute, though, is that Amazon is seeking high quality content for the Kindle Singles channel (“Singles will be a highly curated group of content they feel is valuable to their readers” according to the Kindle Expert website). That might make the content more desirable by patrons and more likely to be considered preservation-worthy. (You can read about one author’s perspective on publishing in the Kindle Singles program.)

Kindle for PC with Accessibility Plugin

Kindle for PC with Accessibility Plugin is a free application for your Windows PC. It provides the following accessibility features:

• Text-to-speech reading with adjustable voice settings
• Voice-guided menu navigation
• Large font sizes
• High contrast reading mode
• Keyboard navigation
• Accessible shortcuts

Because this software is an assistive technology, there are no restrictions on text-to-speech reading. In order to use the text-to-speech feature, an external screen reader program must be installed and running on the Windows PC. Tested screen readers include: JAWS and NVDA. An external screen reader is used to read aloud menus and navigation items, while book text is read by a built-in text-to-speech engine.

Although I’m hard pressed to find the formal announcement, a version of the Kindle for PC with Accessibility Plugin was made available earlier this month. The National Federation of the Blind has a review of the software with some constructive criticism that hopefully Amazon will take to heart. What is interesting is that one can use a screen reading program such as the commercial Jaws for Windows or the open source NonVisual Desktop Access (NVDA) to have the text of the book read aloud “regardless of a publisher’s [text-to-speech] … choice.” If you are serving a population of users with a sight impairment, this may be an option to look at to expand the universe of accessible materials to everything available in the Kindle store.

Peer review: Trial by Twitter

For many researchers, the pace and tone of this online review can be intimidating — and can sometimes feel like an attack. How are authors supposed to respond to critiques coming from all directions? Should they even respond at all? Or should they confine their replies to the conventional, more deliberative realm of conferences and journals? “The speed of communication is ahead of the sheer time needed to think and get in the lab and work,” said Felisa Wolfe-Simon, a postdoctoral fellow at the NASA Astrobiology Institute in Mountain View, California, and the lead author on the arsenic paper. Aptly enough, she circulated that comment as a tweet on Twitter, which is used by many scientists to call attention to longer articles and blog posts.

To bring some order to this chaos, it looks as though a new set of cultural norms will be needed, along with an online infrastructure to support them. The idea of open, online peer review is hardly new. Since Internet usage began to swell in the 1990s, enthusiasts have been arguing that online commenting could and should replace the traditional process of pre-publication peer review that journals carry out to decide whether a paper is worth publishing.

This article in Nature News points out the problem when commentary on scientific studies moves at Twitter speed. The old mechanisms of published peer-reviewed articles followed by commentary in later issue of the same journal in the form of published letters is being challenged by the internet world of blogs and tweets. As the author says, a new form of cultural norms is required as well as mechanisms to track the discourse. [Via Eric Schmell]

eBook Identifier Confusion Shakes Book Industry

Last Thursday, I was fortunate to be at a presentation of the Book Industry Study Group (BISG) about identification of eBooks. BISG hired Michael Cairns, the principal of Information Media Partners, to do a study of the use, issues and practice surrounding assignment of ISBNs in the US book industry. Think of him as a structural engineer hired to inspect the damage to the supply chain’s supporting infrastructure after an earthquake. Cairns conducted 55 separate interviews with a total of 75 industry experts from all facets of the industry. (I was interviewed for my expertise in the use of ISBN in library linking systems).

• BISG eBook ISBN Study Findings Released Michael Cairns’ blog
• Summary of BISG Presentation From BISG, PDF 730 KB

Cairns (@personanondata on Twitter) is an industry veteran- he’s held senior executive positions at Bowker and other companies. His presentation was clear and direct, and he quickly went to the heart of the matter. He found very little support for the policy set forth by the 2005 revision of the ISBN standard regarding when to assign a new ISBN to an ebook.

Eric Hellman writes about his views of the dysfunction surrounding ISBN assignments for ebooks. “What problems?” you might ask — Eric writes has an example of how Barnes and Noble was enhancing some ebooks for their Nook platform. By itself, this activity wouldn’t result in assigning a new ISBN. But because publishers are now exerting more control over setting the prices of ebooks (the so-called “agency model“) the existence of these Nook-enhanced versions needs to cross back-and-forth between the publisher’s and retailer’s electronic systems. The only commonly agreed upon identifier? The ISBN. And this proliferation of ISBN assignments is making trouble for library’s efforts to effectively identify material — which is to say nothing about what it is doing to our efforts to shoehorn these distinctions between various works into the MARC format used by our catalogs. Is that a separate record for that manifestation with a different ISBN?

In preparation for the last webinar of the three-part series “Using RDA: Moving into the Metadata Future“, I’m reading again Karen Coyle‘s “Library Data in a Modern Context” — the first chapter ofUnderstanding the Semantic Web: Bibliographic Data and Metadata. Right at the start she has a clear and useful definition of this thing we call “metadata.”

The most common definition of metadata is “data about data.” This short, catchy definition is worthy of a successful advertising campaign. Unfortunately, it doesn’t really help us understand metadata, and is actually somewhat incorrect. A more useful definition is decidedly less snappy, but can help us understand the helpful role that metadata can play in facilitating information access. In fact, a functional definition gives us a viable roadmap for our own studies of metadata utility and quality.

So here it goes—metadata is constructed, constructive, and actionable:

• Constructed: Metadata is not found in nature. It is entirely an invention; it is an artificiality.
• Constructive: Metadata is constructed for some purpose, some activity, to solve some problem. The proliferation of metadata formats that seem similar on the surface is often evidence of different definitions of needs or of different contexts. We may dream of a universal set of metadata for some set of things, like biological entities, printed books, or a calendar of events, but are likely to be disappointed in practice.
• Actionable: The point of metadata is to be useful in some way. This means that it is important that one can act on the metadata in a way that satisfies some needs.¹

A little further on Karen focuses on the actionablity of metadata. I have a heightened awareness of the need for other-than-visual access to information based on the last few months of activity with my previous employer, so I reread this section with “new eyes” (so to speak):

…today’s metadata must be in a form that can be processed by computers, and the sense that it is “actionable” really needs to be interpreted as being “actionable by electronic machines.” Even when the final goal is to display the data to humans in an understandable form, the data will undergo some machine processing on the way to its destination on a screen [or] in printed form or when read aloud by a screen reader.

I added that last part. The transformation of the meaning of the metadata into a visual form is but one possible sensory input across the human-computer divide. It is important to also design interfaces that bring meaning to data by supplying labels to values in alternate ways. For the MARC 300 field, it is the difference between “ix, 74 p. : ill. ; 23 cm” and “9 pages of introductory material followed by 74 numbered pages. Includes illustrations. 23 centimeters high.” If the only way to transmit this information was auditory, which one of these would you like spoken to you? Is it: “eye-ex, seventy four pee. ill. twenty three cem”?

Now let’s try to engineer that backwards. Is the auditory version easier to do with:

300    |aix, 74 p. :|bill. ;|c23 cm

or something like this made-up, MODS-like markup:

<physicaldescription>
  <extent>
    <pagination>
       <pages type="introductory">9</pages>
       <pages type="numbered">74</pages>
    </pagination>
    <illustration />
    <height unit="cm">23</height>
  </extent>
</physicaldescription>

With the second, we can produce something like the first — or even the abbreviated display version. But it is considerably more difficult to create the auditory version from the first, particularly with the wide variation of punctuation encoding ISBD offers. It just isn’t machine actionable, which makes it difficult to transform, reuse, and translate that data in another context.

I’m reminded too of this recent quote from Jonathan Rochkind: “Of course, our legacy environment is even worse, with the ‘data model’ being supplied by an unholy combination of ISBD … and MARC….” It would be good to stop doing our data entry in the language of the computer (e.g. MARC). Based on the chat from the first webinar in the series, we wouldn’t expect catalogers to type out the XML fragment above. There should be computer-assisted workflows to capture the data and store it with all the required semantics. That XML would be used for machine-to-machine communication and transformation into the output desired by the user — be it a short-hand visual display or an auditory reading of information.

Footnotes

1. Coyle, Karen. “Library Data in a Modern Context.” Library Technology Reports 46.1 (2010): 5-13.

My place of work is looking to acquire educational videos in a digital form with an eye towards long-term preservation. At this point we receive a physical form (preferably DVD, but sometimes VHS) and digitize it to a very lossy access format (RealMedia, in this case). With this change, we would get a preservation-worthy digital copy from the producer/distributor and forego the physical version.

There is quite a lot written on preserving video, but I wanted to distill the requirements down into statements that vendors could reasonably provide today. I think these are pretty sound requirements, but I’m looking for feedback. In particular, I’m not quite sure how to handle the transfer of closed caption text from the publisher/distributor; suggestions are welcome.

[Jester's note: I just realized that an earlier version of this posting went out to the net about two hours before this "final" version. Sorry about publishing the work-in-progress early; I must have hit the wrong button in the new version of WordPress...]

File Formats

Guidance on the preservation of digital video should, by necessity, change over time. [...] The MPEG-2 and MPEG-4 formats are better suited to high-quality digital video. MPEG-2 is better known for its use as a format for DVD-Video, which encourages confidence when considering the likelihood that the format will be readable in the long-term. The format has an average transfer rate of 2-5 megabits per second, but there may be disk space restraints and the software tools necessary to convert and store this format are costly. MPEG-4 has a lower transfer rate of 1-2 megabits per second and is intended for streaming video. Other codecs, such as QuickTime, Windows Media, Real Video and Open DIVX, are useful for specific purposes, but not suitable for preservation. ¹

The Library of Congress Sustainability of Digital Formats site has an entry for MPEG-2 (also known as H.262) and an entry for MPEG-4 (more completely, MPEG-4 file format version #2) that give the nitty-gritty details for the file formats.

The preservation master copies we want to store has a frame size of 720 pixels by 480 pixels. (That size is for NTSC format videos, common in USA, Canada and Japan. Master copies of PAL-format videos, common in Australia, New Zealand, the United Kingdom and most of Europe, is 720 x 576.) This is the standard resolution used in MPEG-2-compressed commercially distributed DVD movies.² These frame sizes are appropriate for analog video signals. (“As defined by ITU-R Recommendation BT.601, more commonly know by the abbreviations Rec. 601 or BT.601 or its former name, CCIR 601. [It is] a standard published by the CCIR (now ITU-R) for encoding interlaced analogue video signals in digital form.”³ ) The audio is 48KHz stereo at 224 kb/s or better.

Captioning Text

To make matters more complicated, a whole set of different schemes are used for DVDs. (On VHS recordings, closed caption text was encoded in one of the non-visible lines that make up the video signal. Since the DVD format only included visible lines, other schemes were required.) The most popular seems to be the Scenarist Closed Caption (SCC) format. This is a binary file that exists on the DVD along side the video files.

Resources Consulted

The text was modified to update a link from http://ahds.ac.uk/ to http://www.ahds.ac.uk/ on January 28th, 2011.

The text was modified to update a link from http://ahds.ac.uk/preservation/ahds-preservation-documents.htm to http://www.ahds.ac.uk/preservation/ahds-preservation-documents.htm on January 28th, 2011.

The text was modified to update a link from http://ahds.ac.uk/preservation/video-preservation-handbook.pdf to http://www.ahds.ac.uk/preservation/video-preservation-handbook.pdf on January 28th, 2011.

The text was modified to update a link from http://ahds.ac.uk/preservation/video-preservation-handbook.pdf to http://www.ahds.ac.uk/preservation/video-preservation-handbook.pdf on January 28th, 2011.

The text was modified to update a link from http://ncam.wgbh.org/publications/adm/guideline_h.html to http://ncam.wgbh.org/invent_build/web_multimedia/accessible-digital-media-guide/guideline-h-multimedia on January 28th, 2011.

Footnotes

1. Knight, G., & McHugh, J. (2005). Preservation Handbook: Moving Image. p. 3.
2. Audio/Video Capture and Management (2002).
3. “Rec. 601″ (2008).

A few months back I referred to a project that used video to present information about accessibility needs in the classroom. That article was about how difficult it is to create markup for embedded video that is universally accessible and valid HTML. Late last month the larger project that used that work was released. Called the Faculty & Administrator Modules in Higher Education, or FAME, it is a professional development tool for use in higher education with information on how college faculty, administrators, disability service providers, and students can work individually and collaboratively to improve the accommodations, teaching-learning process, and overall campus environment for students with disabilities. The content on the website is broken up into five modules:

• Rights and responsibilities of faculty, students, and disability service providers in the accommodations and instructional process;
• Universal Design for Learning (UDL) approach to instruction;
• Web accessibility and assistive technology;
• College writing challenges and effective teaching practices; and
• Assessment of the campus climate towards students with disabilities.

Each module contains a video introduction, practitioner-oriented commentary, interactive case studies, and references to other material. One can even download the FAME content to be personalized and mounted on an institution’s own site. (OhioLINK has offered to host the streaming video content for FAME even if an institution downloads and personalizes the content, and we can also make the video files available to institutions in Quicktime, Windows Media, and Real Media formats to mount on their own servers as well.)

I invite you to take a look at the site. It was a pleasure to work with the project team to bring the work of the researchers, writers, editors and technologists to bring the project to this stage. The FAME Project came about through training grant awarded to The Ohio State University from the Office of Post-Secondary Education, U.S. Department of Education (P333A020033-03). The FAME Project Director was Dr. Margo Izzo at The Ohio State University.

The text was modified to update a link from http://www.oln.org/ILT/ada/Fame/rr/f1_1_1.html to http://fame.oln.org//rr/f1_1_1.html on December 31st, 2010.

The text was modified to update a link from http://www.oln.org/ILT/ada/Fame/udl/f2_11_145.html to http://fame.oln.org/udl/f2_11_145.html on December 31st, 2010.

The text was modified to update a link from http://www.oln.org/ILT/ada/Fame/web/f3_13_150.html to http://fame.oln.org/web/f3_13_150.html on December 31st, 2010.

The text was modified to update a link from http://www.oln.org/ILT/ada/Fame/cw/f4_14_151.html to http://fame.oln.org/cw/f4_14_151.html on December 31st, 2010.

The text was modified to update a link from http://www.oln.org/ILT/ada/Fame/ca/f5_15_152.html to http://fame.oln.org/ca/f5_15_152.html on December 31st, 2010.

The text was modified to update a link from http://www.oln.org/ILT/ada/Fame/help_5.html to http://fame.oln.org/help_5.html on December 31st, 2010.

The text was modified to update a link from http://nisonger.osu.edu/izzo.htm to http://nisonger.osu.edu/bios/izzo.htm on January 20th, 2011.

The text was modified to update a link from http://nisonger.osu.edu/bios/izzo.htm to http://replay.web.archive.org/20080705040726/http://nisonger.osu.edu/bios/izzo.htm on May 17th, 2011.

With the release of Microsoft’s Windows Media Player version 11, the Microsoft Media Server (MMS) protocol is officially no longer supported. (Except, of course, for the confusing/amusing footnote on that page that says ‘mms://’ URIs are “highly recommended” as a protocol rollover URL — only Microsoft can at the same time make something deprecated and highly recommended.) As Ryan Eby noted earlier this year, those generating ASX files for Windows Media Player need to adjust their scripts.

Last year I published an entry called Embedded Web Video in a Standards-Compliant, Accessible, and Successful Way on how to embed (without using the non-standard <EMBED> tag) video on an HTML page. It has been one of the most widely read articles on DLTJ.org, and so I wanted to publish an updated version of the script from that article to take into account this new wrinkle from Microsoft. The change is at line #41 below:

#!/usr/bin/perl -w
# Copyright (C) 2006-2007 OhioLINK
#
# This file is part of the OhioLINK Digital Resource Commons (DRC) Project.
#
# The OhioLINK DRC is free software; you can redistribute it and/or
# modify it under the terms of the Affero General Public License as
# published by Affero, Inc. -- either version 1 of the License, or
# (at your option) any later version.
#
# The OhioLINK DRC Project is distributed in the hope that it will be
# useful, but WITHOUT ANY WARRANTY -- without even the implied warranty
# of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# Affero General Public License for more details.
#
# You should have received a copy of the Affero General Public
# License in the LICENSE.txt file that comes with the DRC project;
# if not, write to DRC Development Team, OhioLINK, 2455 North Star Rd,
# Suite 300, Columbus, OH 43221, USA.
 
if (!$ENV{PATH_INFO}) {
  print "Location: http://no-path-info-given/\\r\\n\\r\\n";
} else {
  ($format,$id) = $ENV{PATH_INFO} =~ q#^/+(.*?)/(.*)$#;
 
  if ($format =~ /Quicktime/i) {
    print "Location: http://video.ohiolink.edu/blah/Quicktime/$id\\r\\n\\r\\n";
  } elsif ($format =~ /Real/i) {
    print "Location: http://video.ohiolink.edu:8080/ramgen/blah/Real/$id\\r\\n\\r\\n";
  } elsif ($format =~ /Windows/i) {
    ($winType,$winFile) = $id =~ q#^(.*?)/(.*)$#;
    if ($winType =~ /asx/i) {
      $winFile =~ s/\\..*$//;
      print >> "EoMarkup";
Content-type: video/x-ms-asf
 
<asx version="3.0">
<copyright>(c) 2005 - xxx</copyright>
<entry>
<ref href="mms://video.ohiolink.edu/blah/Windows/$winFile.wmv?SAMI=http://rave.ohiolink.edu/dmc/blah/windows/smi/$winFile.smi">
<ref href="http://video.ohiolink.edu/blah/Windows/$winFile.wmv?SAMI=http://rave.ohiolink.edu/dmc/blah/windows/smi/$winFile.smi"/>
<copyright>(c) 2005 - xxx</copyright>
</ref></entry>
</asx>
EoMarkup
    } elsif ($winType =~ /wmv/i) {
      print "Location: mms://video.ohiolink.edu/blah/Windows/$winFile\\r\\n\\r\\n";
    } elsif ($winType =~ /smi/i) {
      use LWP::UserAgent;
      $ua = LWP::UserAgent->new;
      $ua->agent("$0-lwp/0.1 " . $ua->agent);
      $req = HTTP::Request->new(GET => "http://video.ohiolink.edu:8080/blah/Windows/$winFile");
      # send request
      $res = $ua->request($req);
      # check the outcome
      if ($res->is_success) {
        print "Content-type: application/smil\\r\\n\\r\\n";
        print $res->decoded_content;
      } else {
        print "Location: http://error-from-remote-server/$winType/$winFile/".$res->code."/".$res->message."\\r\\n\\r\\n";
      }
    } else {
      print "Location: http://invalid-Windows-format-given/$winType/$winFile\\r\\n\\r\\n";
    }
  } else {
    print "Location: http://invalid-format-given/$format/$id\\r\\n\\r\\n";
  }
}

Thanks to Neil Bennett at the University of Southern Maine for contacting OhioLINK about the problem, providing some very helpful diagnostics, and pointing us to the URL to the protocol table mentioned above. It is also worth noting that the A List Apart website posted a new article about sane ways of embedding Flash content that builds upon the same work in the original ‘Embedded Web Video…’ article. It might be time to update some of the techniques used in the original article, but that’ll need to wait for another time.

The text was modified to remove a link to http://blog.ryaneby.com/archives/windows-media-player-11-and-mms/ on January 19th, 2011.

The word “Successful” in the title, when juxtaposed with “Standards-Compliant” and “Accessible,” should be big, bold and flashing (except that the flashing style would then go against web accessibility best practice). The goal is to embed a video clip into a web page that validates as “XHTML4.01 Transitional”, includes a Closed Captioning text track to be displayed in the web page, and could be viewed in one of three flavors: Windows Media, QuickTime, and Real. And the content being presented is about using accessible technologies in the classroom, so it had to be “right.” This task was much harder than I thought, and I’ll offer much harder than it should have been. Piecing together sources too numerous to mention, I managed to make it happen … with just a few caveats. Here, documented for all time, or at least until dltj.org goes away or the next major browser/streaming-client revision (which ever comes first) is how it can be done.

The Content

Windows/

.wmv (the video) and .smi (the closed caption text track)

Real/

.rm (the video), .rt (the closed caption text track) and .smi (the container that pulls the first two together)

Quicktime/

.mov (the video)

Now right out of the gate we’re fudging things a little bit. For whatever reason the team developing the content decided to punt when it came to the text track in Quicktime. I don’t know if there was an insurmountable barrier or some other reason, but the practical upshot is that the Quicktime version of the video includes the text track an “open caption” encoded right into the video stream. That makes Quicktime, from my perspective, very easy to deal with.

Those with a keen eye will notice that both the Windows Media and the Real Media version have a .smi file. This is true, but they are not identical. Windows media wants to use a .asx file as its container object and only uses the .smi for the text stream. The Real Media version has the text stream in .rt files. Could these be combined? Perhaps, but I’ve got real-world problems to solve and this is what I was given. In any case, I don’t think it makes the end result any easier or harder than it would be otherwise.

Serving Up the Content

For the purposes of this project, these RAVE URLs were defined as this (the http protocol prefix is omitted so over-anxious RSS readers will not attempt to turn them into hyperlinks; “blah” is a placeholder for the project name; and [id] represents the identifier for the video segment):

rave.ohiolink.edu/dmc/blah/quicktime/[id]

Redirects to the location of the Quicktime file (a hinted .mov file, so it starts playing in the browser right away)

rave.ohiolink.edu/dmc/blah/real/[id]

Redirects to the location of the .smi container file via the mms protocol through the Helix streaming server

rave.ohiolink.edu/dmc/blah/windows/wmv/[id]

Redirects to the location of the wmv video file via the mms protocol through the Helix streaming server

rave.ohiolink.edu/dmc/blah/windows/smi/[id]

Pulls the .smi file off of the streaming server and sends it back to the browser with the appropriate MIME type

rave.ohiolink.edu/dmc/blah/windows/asx/[id]

Dynamically creates a .asx container that pulls together the windows/smi and the windows/wmv files

Here are the first of the tricky bits. First, it seems like Windows Media Player can’t cope with a 302 redirect message in response to its request for a .smi file. “Can’t cope” can be restated as “ignores”; it doesn’t throw an error, it just plays the file as if there was no closed captioning text. To get around this, the RAVE script has a bit of PERL where it asks like a web client to pull the .smi file off of the video server and send it back out to the media player.

Second — again for those with eagle eyes — is the dynamic generation of an .asx file. As it turns out, one can relate a .smi text-track file with a .wmv video file by including it as a SAMI parameter on the URL. By far the best practice for doing this seems to be to relate the .smi and the .wmv files in a .asx container file. So we create one on-the-fly. The PERL code looks like this:

#!/usr/bin/perl -w
# Copyright (C) 2006 OhioLINK
#
# This file is part of the OhioLINK Digital Resource Commons (DRC) Project.
#
# The OhioLINK DRC is free software; you can redistribute it and/or
# modify it under the terms of the Affero General Public License as
# published by Affero, Inc. -- either version 1 of the License, or
# (at your option) any later version.
#
# The OhioLINK DRC Project is distributed in the hope that it will be
# useful, but WITHOUT ANY WARRANTY -- without even the implied warranty
# of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# Affero General Public License for more details.
#
# You should have received a copy of the Affero General Public
# License in the LICENSE.txt file that comes with the DRC project;
# if not, write to DRC Development Team, OhioLINK, 2455 North Star Rd, 
# Suite 300, Columbus, OH 43221, USA.
 
if (!$ENV{PATH_INFO}) {
  print "Location: http://no-path-info-given/\r\n\r\n";
} else {
  ($format,$id) = $ENV{PATH_INFO} =~ q#^/+(.*?)/(.*)$#;
 
  if ($format =~ /Quicktime/i) {
    print "Location: http://video.ohiolink.edu/blah/Quicktime/$id\r\n\r\n";
  } elsif ($format =~ /Real/i) {
    print "Location: http://video.ohiolink.edu:8080/ramgen/blah/Real/$id\r\n\r\n"; 
  } elsif ($format =~ /Windows/i) {
    ($winType,$winFile) = $id =~ q#^(.*?)/(.*)$#;
    if ($winType =~ /asx/i) {
      $winFile =~ s/\..*$//;
      print >> "EoMarkup";
Content-type: video/x-ms-asf
 
<asx version="3.0">
<copyright>(c) 2005 - xxx</copyright>
<entry>
<ref href="mms://video.ohiolink.edu/blah/Windows/$winFile.wmv?SAMI=http://rave.ohiolink.edu/dmc/blah/windows/smi/$winFile.smi">
<copyright>(c) 2005 - xxx</copyright>
</ref></entry>
</asx> 
EoMarkup
    } elsif ($winType =~ /wmv/i) {
      print "Location: mms://video.ohiolink.edu/blah/Windows/$winFile\r\n\r\n";
    } elsif ($winType =~ /smi/i) {
      use LWP::UserAgent;
      $ua = LWP::UserAgent->new;
      $ua->agent("$0-lwp/0.1 " . $ua->agent);
      $req = HTTP::Request->new(GET => "http://video.ohiolink.edu:8080/blah/Windows/$winFile");
      # send request
      $res = $ua->request($req);
      # check the outcome
      if ($res->is_success) {
        print "Content-type: application/smil\r\n\r\n";
        print $res->decoded_content;
      } else {
        print "Location: http://error-from-remote-server/$winType/$winFile/".$res->code."/".$res->message."\r\n\r\n";
      }
    } else {
      print "Location: http://invalid-Windows-format-given/$winType/$winFile\r\n\r\n";
    }
  } else {
    print "Location: http://invalid-format-given/$format/$id\r\n\r\n";
  }
}

The first part of the script parses the PATH_INFO variable — everything left over from the blah script name — and if what is requested is the Real Media or the Quicktime version of the video it sends the redirect back to the client (in the form of the “Location:” header with Apache HTTP daemon handling the 302 response code). If what is requested is the Windows variety, it further parses the PATH_INFO piece for the file type and acts according to that: for wmv, it redirects; for asx, it generates the .asx file; and for .smi, it pulls the content off the video server and returns it to the client.

The Markup

Also note that many of the recommendations out there start off with something like “if you have media to show, don’t embed it into your web page; but if you must, here is one way to do it.” The reason for this is pretty simple, if not obvious after a little thought: folks using alternate browsing/computing techniques (e.g. keyboard only for limited mobility, auditory only for sight impaired, visual only for the hearing impaired, etc.) lose much of their ability to control the flow of information because it is tied up in the functionally-limited browser rather than the native media player. These same recommendations go on to say that if you do embed the media into the web page, provide a link for the user to access it using the native media player.

So based on the URLs to the media objects described above, this is what the HTML markup looks like:

Quicktime

<object classid="clsid:02BF25D5-8C17-4B23-BC80-D3488ABDDC6B" codebase="http://www.apple.com/qtactivex/qtplugin.cab" width="320" height="380">
  <param name="src" value="http://rave.ohiolink.edu/dmc/blah/quicktime/[id].mov" />
  <param name="controller" value="true" />
  <param name="autoplay" value="true" />
  <!--[if !IE]>-->
    </object><object type="video/quicktime" data="http://rave.ohiolink.edu/dmc/blah/quicktime/[id].mov" width="320" height="380">
     <param name="autoplay" value="true" />
     <param name="controller" value="true" />
    </object>
   <!--<![endif]-->
 
&lt;br /&gt;
<a href="http://rave.ohiolink.edu/dmc/blah/quicktime/[id].mov" title="View in Native Player">View Video with External Player</a>

Windows Media

<object classid="clsid:6bf52a52-394a-11d3-b153-00c04f79faa6" type="application/x-oleobject" width="320" height="304" id="Player1">
  <param name="url" value="http://rave.ohiolink.edu/dmc/blah/windows/asx/[id].asx" />
  <param name="src" value="http://rave.ohiolink.edu/dmc/blah/windows/asx/[id].asx" />
  <param name="autostart" value="true" />
  <param name="showcontrols" value="true" />
  <param name="uimode" value="mini" />
  <param name="captioningID" value="CapText" />
  <param name="SAMIFileName" value="http://rave.ohiolink.edu/dmc/blah/windows/smi/scott.smi" />
    <!--[if !IE]>-->
     </object><object type="video/x-ms-wmv" data="http://rave.ohiolink.edu/dmc/blah/windows/asx/[id].asx" width="320" height="304" id="Player2">
     <param name="src" value="http://rave.ohiolink.edu/dmc/blah/windows/asx/[id].asx" />
     <param name="autostart" value="true" />
     <param name="showcontrols" value="true" />
     <param name="uimode" value="mini" />
     <param name="captioningID" value="CapText" />
     <param name="SAMIFileName" value="http://rave.ohiolink.edu/dmc/blah/Windows/smi/[id].smi" />
    </object>
   <!--!<[endif]-->
 
&lt;br /&gt;
<a href="http://rave.ohiolink.edu/dmc/blah/windows/asx/[id].asx" title="View in Native Player">View Video with External Player (including captions)</a>

Real Media

<script language="JavaScript" type="text/javascript">
  AC_RunRealContent( 
	"id", "player",  
	"width", "320",  
	"height", "280",  
	"CONTROLS", "imagewindow",  
	"CONSOLE", "radio",  
	"AUTOSTART", "TRUE",  
	"type", "audio/x-pn-realaudio-plugin",  
	"SRC", "http://rave.ohiolink.edu/dmc/blah/real/[id].smi"
  );
  window.document.write('&lt;br /&gt;');
  AC_RunRealContent( 
	"id", "controls",  
	"width", "320",  
	"height", "36",  
	"CONTROLS", "ControlPanel",  
	"CONSOLE", "radio", 
	"type", "audio/x-pn-realaudio-plugin",  
	"SRC", "http://rave.ohiolink.edu/dmc/blah/real/[id].smi"
  );
</script>
&lt;br /&gt;
<a href="http://rave.ohiolink.edu/dmc/fame/Real/scott.smi" title="View with Native Player">View Video with External Player (including captions)</a>

Conclusion

1. It seems to work for me and the machines I test with; your mileage may vary.
2. If you know of a better way to do it, please let me know!

Resources Consulted

• “Bye Bye Embed” by Elizabeth Castro on A List Apart
• “Web Captioning” in the Web Accessibility In Mind project