Putting Video on the Web - A Practical Guide to Video and Audio Compression - page 419

The example .asx file is set up for playing a Windows Media video clip. It could be
stored with a .wmv extension. The .wax files are almost identical except that their file ref-
erences are to .wma files containing audio.
The benefit of having almost identical .asx , .wvx , and .wax files is that each kind
of metafile can be associated with a different helper application or plug-in.

26.9 Real Networks

The metafiles for Real Networks are rather simpler. They are just a list of URLs for the
media to be played. In this example some progressive downloads via http files are
invoked. A Synchronized Multimedia Integration Language (SMIL, pronounced “smile”)
presentation is streamed and some local files are played. Then the metafile stops. The
media item at the end of the metafile after the stop won't be played.
The listing below shows a Real Networks metafile.

http://www.contactright.com/media/video1.rm
http://www.bbc.co.uk/media/video2.rm
http://www.contactright.com/media/sample1.smil
rtsp://server.real.com:554/sample.smil
file://mymedia/video1.rm
file://mymedia/video2.rm
file://mymedia/sample1.smil
—stop—
pnm:// server.real.com:7070/sample.rm

26.10 QuickTime

QuickTime uses a reference movie, which has the same file extension as a normal movie.
The nature of the file is not apparent until the file is opened, at which time it turns out to
refer to other files. This is an integral feature of QuickTime movies: they can refer to video
content in other external movie containers.
To make reference movies you will need to download the MakeRefMovie tool from
the Apple QuickTime web site. With this you will be able to compile the binary QuickTime
ref movies that you'll refer to from the web pages.

Apple QuickTime: http://www.apple.com/quicktime/