Captioning with a SMIL :-)

One of the many uses of SMIL is to add text captions to video or audio content. At this time, Real provides the best documentation and support for the use of SMIL for text captions, using its XML-based RealText format. The major problem here is finding the documentation on Reals indecipherable and annoying website!

Overview- captioning using SMIL is fairly simple. First, you set your regions up with SMIL for your video/audio and text to play in. You then create a RealText file (.rt) that will play in the text region. The new RealOne player will also support plain text (.txt) files as well, but RealText gives you lots of control over what happens with the text.

You then have a decision to make about your text window. RealText allows several methods of text presentation and timing. The easiest to use is scrolling text.

Scrolling text example

You can also use scrolling or paging text with multiple windows, in multiple languages.

Two-window captioning

However, this can get old really quickly. Another method is to use "paging" text, where text is synchronized to the video in a series of static pages.

"paging" text example except this scrolls as well :-( students....grr.....

Paging text is harder to setup initially, but I think it works better for longer presentations. Using scrolling text is difficult, because the scrollrate can fall out of sync with the audio over time. You also need a reasonably sized window to use scrolling text.

Here are some direct links, that will hopefully work for a little while. Always pay attention to dates when using Reals sites, they are poorly organized and contain lots of older material. I have also found it very useful to search Reals sites using Google.

Current information on SMIL 2.0 implementation- If your not familiar with how SMIL works in the RealOne player, this can help.

RealSystem iQ Production Guide- contains the latest information on the RealText implementation.

Workshop Files- we will use these files in our workshop today.

"We're Texas" encoded in RealVideo 9 at 768K, 640X480, 30fps. Here's a captioned version by one of my students.

Video Transcript from Diane, converted to text-only.

Other versions of the "We're Texas" video.

269K320X240fps15.rm is a standard encode I do for Texas Legacy work, RealVideo 8.

48K240X180fps10.rm is a standard modem encode I do for Texas Legacy work, RealVideo 8.

32Kaud.rm is a standard audio-only encode I do for Texas Legacy work, RealAudio 8.

ISMAProfile0.rm is the Internet Streaming Media Alliance specification.

ISMAProfile1.rm is the Internet Streaming Media Alliance specification for Profile 1.