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Re: Accessible podcasts

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From: Greg Kraus
Date: Mar 22, 2006 11:50AM

On Mar 21, 2006, at 2:42 PM, Sandra Andrews wrote:
> The presenter replied that since video podcasts are essentially
> quicktime files, we could do closed captioning via Final Cut Pro.
> Video podcasts include powerpoints and static images that can be
> synched to the audio.

Video Podcasts on the Video iPod are files that QuickTime can play, but
they are not capable of supporting a text track which is what is
usually used for captioning. You could combine the captioning on top
of the video, but it could not be accessed as a text track would with a
QuickTime movie. It would simply be text imposed on top of a picture.

In terms of the size of the image, the iPod plays video back at 320
pixels by 240 pixels, but you can actually make your video podcast
larger. I have made ones at 480 pixels by 360 pixels. (The actual
upper limit I believe is around 553 pixels by 415 pixels at a 4:3
screen dimension.) The iPod will just downsize your video during
playback. However, video podcasts (or vodcasts) do not have to be
viewed on an iPod. If a person viewed the podcast in iTunes or in
QuickTime, they could see it at the larger resolution.

On Mar 21, 2006, at 2:58 PM, Patrick H. Lauke wrote:
> Or you could look at using SMIL to combine the video file with a
> separate caption file
>
> http://www.splintered.co.uk/experiments/66/
> http://www.splintered.co.uk/experiments/79/

Patrick's implementation might lead to some promising results. You
could encode your video and audio into an MPEG-4 file and use a SMIL
file to synchronize it with a QuickTime text track. For the accessible
version of your podcast your provide a link to the SMIL file. For the
non-accessible, Video iPod friendly version you simply provide a link
to the MPEG-4 file. You could just make 2 different RSS feeds, or have
two entries in a single RSS feed - one for the accessible SMIL version,
and one for just the MPEG-4 file. I haven't tested this yet, but
probably will be shortly.

> Has anyone tried this solution? If so, report, please, and I can make
> an appointment with our lab to try it out!

We are actually about to begin beta testing a new product we are
developing that will convert Microsoft PowerPoint presentations into
video podcasts, QuickTime movies, and/or accessible websites with audio
narration and transcripts.

Hope this helps.

Greg Kraus
--
LecShare, Inc.
P.O. Box 1119
Clayton, NC 27528
919.934.3810 (voice)
919.882.1275 (fax)
http://www.lecshare.com



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