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With the approach of WCAG 2.0 and the continued rise of user generated content, it seems that there is still a lack of appropriate treatment for video. The technology for achieving WCAG-happy video exists and takes only a little effort to get a big return in added semantic value.

Screencasts are all the rage on the internet at the moment. They improve understanding of difficult or unfamiliar concepts. We use them here in our showreel. If you want to make a WCAG-happy screencast, here’s what you’ll need:

1. JW FLV player
2. YouTube account
3. Cam studio
4. Simple video editor
5. XML editor

1. Make a video

Use Cam Studio and a microphone to capture your screencast presentation. Speak clearly and explain what you’re doing with lots of useful detail. Be aware that your commentary could become the only source of information in some scenarios about your screencast demonstration and it will form the basis for your semantic value.

Following capture place your raw film into an editor like Quicktime or Windows Movie Maker, edit to taste, normalise the audio and save out in a small but high quality format. I use 320 x 240 pixels with very little compression.

2. Make captions

Timed Text (TT) Authoring Format 1.0 is the W3C Standard for making timed text captions for streaming media. It’s an XML file that looks familiar and stores each caption, its starting time, its end time and any support information like visual styling. Here’s and example of TT XML () from our web site. Use it as a template.

Study your video in an editor like Quicktime, transcribe your commentary line by line and add important information essential to understanding the message. This can then be added to the TT XML along with start and end times.

3. Upload to YouTube

Done this before? If not, sign up to YouTube, create your channel and upload your processed video. Use the upload process to add appropriate semantic information to your video entry. It all takes a few minutes to cook but when done you’ll have a FLV URL and some quality semantic data associated with it hosted by someone else who can pay the streaming costs.

4. Embed FLV player

Add an instance of JW FLV player to your own web page in your domain using SWFobject. Set the “file” parameter of the JW FLV player to your YouTube FLV URL and set the “captions” parameter to the path of your locally hosted TT XML. A full list of all variables is available for the FLV player.

Finally you should see a YouTube branded video appear on your web site with your hosted timed captions. There are no streaming bandwidth costs to your server and you’ll get free statistics from YouTube with semantic promotion through your own YouTube channel.

But importantly you’ll have made an effort to meet some basic accessibility requirements. WCAG-happy video is easier than you think and the semantic benefits are increased infinitely when compared with just video alone. A picture is not worth 1000 words unless it can be found.

What’s your approach?

I have my favourite tools like Cam Studio and the JW player but what do you use? Let us know.

Tags: accessiblity, Cam studio, favourite tools, screencast, semantic, streaming media, WCAG, XML, youtube

This entry was posted on Wednesday, May 28th, 2008 at 7:50 pm and is filed under Semantics, Video. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.