Streaming Media Metafiles

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autoplay="true"
controller="true" />

Where this starts to get interesting is with some of the other options you can add to the embed tag. Many of the available options are similar to the ones available in QuickTime’s HTML embed tag:

—autoplay=(true or false)
—controller=(true or false)
—href=(url to a web page you want to load when the user clicks on the movie)
—loop=(true, false, or palindrome)
—qtnext=(the movie that should play when this one finishes)

There are also a couple of options that are unique to QuickTime link (.QTL) files. The "fullscreen=(normal, double, half, current, or full)" option causes the QuickTime player to take over the screen and display the movie against a black background in a frame size specified by the parameter selected. Normal, double, and half are self-explanatory. The current value will play the movie at the size it was the last time it was saved. "full" will scale the video up to fill the screen as much as possible without clipping or changing the aspect ratio. The "quitwhendone=(true or false)" option causes the player to close automatically when the movie is finished. Use this last one with care. It may seem a nice touch to get the player out of the way and return the user directly to the web page. At the same time, you prevent them from easily playing it again.

Notably absent are the "starttime" and "endtime" options, a disappointing omission. A full list of the options and values supported in the .QTL file’s embed tag is available from Apple’s QuickTime Media Link Documentation.

Another way to look at the options you can use in a .QTL file is to use QuickTime Pro to create it. With your movie open in QuickTime Pro, choose Export->Movie to QuickTime Media Link. The Options button will open a dialog with all of the available options. This can be a good way to get a head start on a .QTL file that you can later tweak. When you save this file, what’s saved is a plain XML file that you can open and edit with any text editor.

Reference Movies
QuickTime also supports a binary reference movie format that can only be created with QuickTime Pro or other specialized authoring programs. The native format offers more capability than do the text-based formats, such as specifying alternate movies for users connecting at different bandwidths. The advantage of the text-based metafiles is that they are simple to create and manage with no special tools at all. Perhaps the greatest benefit comes from the ability to automate the authoring and delivery management process by generating metafiles with scripts.

SMIL
You can also use Synchronized Multimedia Integration Language (SMIL), an XML-based language, to create standardized metafiles. That’s beyond the scope of this article, but more information can be found at Apple’s Scriptable Applications page for QuickTime, www.apple.com/applescript/quicktime/.

As with all technical solutions, no one size fits all. The best way to sort out the different options for QuickTime delivery is to try a few. Then use the simplest one that meets your needs.

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