[Accessibleweb] Test requested: Closed-captioned web videos

Terry Thompson tft at u.washington.edu
Mon Jun 7 10:05:59 PDT 2004


I see you're presenting this Thursday on captioning videos, so I thought
I'd better hurry up and reply to the latter part of your original post
re. captioning for Flash.

If you're just interested in finding out what I think could be the best
current solution, skip to the section of my post titled "Alternative
Solution #2", near the bottom.

For those of you who are interested in all the boring technical details
that led me to Alternative Solution #2, please read on...

I've done quite a bit of work exploring this with Web Services at
Western Washington University, where they have a series of help desk
videos they were wanting to caption. Like you, they created their
videos using Camtasia.

As you mentioned, Camtasia has the ability to produce videos in many
formats. The format of choice for Western was .SWF, as they found this
yielded the best quality in the smallest file size. They also were
hoping to deploy it using an embedded Flash player, since Macromedia
claims the Flash player is installed on over 90% of desktops, and
Western's own traffic logs confirmed that over 90% of visitors to its
home page had Flash installed. The Flash Player is also more universally
cross-platform than any other media player.

Before committing to the Flash Player, however, there were (and still
are) two accessibility issues that need to be addressed: There must be a
way to synchronize the closed captions with the video; and the movie
controller must be keyboard operable. Here's what I've learned about

* Captions in Flash *

Magpie is able to read an .SWF file and interact with it using its
QuickTime player. So it's pretty easy to do the actual captioning work.
The difficulty is in producing a final caption product that Flash can

The only solution I could find a few months ago was this Magpie
captioner extension available for Flash:

This extension is able to read a *.magpie file and display its content
as captions on the Flash "stage". The *.magpie file is an xml file
created by Magpie as its "project file". For all other media players,
the final step in creating captions with Magpie is to export the
*.magpie file to the appropriate standard-compliant format for your
video (SMIL for Real and QuickTime; SAMI for Windows media). However,
all the necessary caption content and time synch data is also available
in the *.magpie file, which is what the Flash caption extension

This extension, however, was developed by a lone programmer and has
several bugs, the most significant of which is its inability to synch
the captions with a movie controller. So, if your video includes a
controller, it simply does not work - users can pause the video, but the
caption track will keep right on playing.

Read on for a possible solution!

* Flash Movie Controller Keyboard Operability*

When you produce a Flash video using Camtasia, Camtasia attaches its own
movie controller (play and pause buttons, slider, etc.) As far as I
could tell, this controller is not keyboard operable - you must be a
mouse user in order to operate it. This same controller can be freely
downloaded as a Flash Component:

If somebody is good with ActionScript, I think they could tweak this
controller to make it keyboard operable. However, they would also need
to script it so that it interacts with the caption track. The folks at
Western thought they could do this, and have played around with it a
bit, but so far haven't come up with a working solution. I and they
still think it's do-able, but it may be easier to just create a new
accessible controller from scratch.

Alternative Solution #1 (QuickTime):

The QuickTime Player can play an .SWF file. It has a keyboard operable
controller, and is capable of displaying SMIL captions. So, if your only
reason for using .SWF is "high quality in a small file", this is a good
solution. It does, however, require that users have the QuickTime player
installed, so it doesn't reach the high percentage of computers that
Flash does. Western is using this approach for now, as an interim
solution until we can find an accessible solution using the Flash

Alternative Solution #2 (HiCaption?)

HiSoftware has a product called Hi-Caption SE for Macromedia Flash MX,
which comes with its own Flash viewer component. This product has a
price tag, in contrast to Magpie, which is free. However, it's only
$99.99, not much as software goes...

I haven't had a chance to look at this yet, but if it lives up to its
marketing claims, it sounds like it may be the best solution.

Here's info from the developer:

And here's a white paper from Macromedia on how to use it (in PDF):


>-----Original Message-----

>From: accessibleweb-bounces at mailman.u.washington.edu

>[mailto:accessibleweb-bounces at mailman.u.washington.edu] On

>Behalf Of Harry Love

>Sent: Friday, May 28, 2004 11:53 AM

>To: accessibleweb at u.washington.edu

>Subject: Re: [Accessibleweb] Test requested: Closed-captioned

>web videos



>Thank you to everyone who tested the videos and to those who

>wrote to me

>with suggestions; all of the feedback was excellent. We will begin

>exploring the issues discussed and implementing some changes

>in the way

>we record and produce these videos. Our hope is that everyone will

>benefit from these design decisions: "universal design," as Terry

>mentioned in one of his comments.


>Thanks to Mailman, all of these suggestions are also archived

>on the Web

>as well (see the link in the email footer).


>*A note to anyone thinking about using Camtasia*

>Camtasia has the ability to produce videos in many formats, including

>AVI, QuickTime, Flash, and RealPlayer. We went with

>RealPlayer because

>the file size output was optimal compared with the other options, and

>the video clarity was ideal. The downside is that Camtasia's

>codec for

>RealPlayer is only available on the Windows platform. In this regard,

>Flash would be our next best choice, as it also produces small files,

>has good video quality, and is available on Windows, Mac, and Linux.

>Our goal is platform- and browser-independence.


>However, I have not found a tool--aside from the Flash authoring

>software itself--that allows for the creation of standards-based

>synchronized media captions in Flash. MAGPie creates captions in SMIL

>format, a W3C recommendation. After the timing is sorted out, updates

>to captions can be made with any text editor, such as Notepad.

> And, as

>SMIL is an open standard, any media player developer may implement the

>SMIL specifications. The same cannot be said with any certainty for

>proprietary media formats.


>If you have created accessible captions in Flash, or have

>worked with a

>tool that does, please let me know.





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