| Real Audio/Video
There is no
server-side Real software installed
however you are still able to stream Real Audio/Video files
using HTTP Streaming.
HTTP streaming is an alternative approach to serving
RealAudio and RealVideo files on the Web without the added
management requirements and expense of server-side streaming
software. Although this techniques is not well-suited for
high-volume sites serving numerous simultaneous streams, many
smaller Web sites can benefit tremendously from this simple
and inexpensive approach.
Actually, it's better
than inexpensive, it's free.
That's because it relies
on HTTP (HyperText Transfer Protocol) which is already used by
all Web servers to store and transmit ordinary text and
graphics files on the Web. And from the producer's point of
view, there's no added effort because RealAudio and RealVideo
files prepared for use on an HTTP server are identical to
those used with a streaming media server.
There are some important
differences however, between the capabilities of HTTP and
specialized server software such as RealNetworks' RealSystem
Server 8.
For example, you can't
automatically detect the user's modem speed using HTTP.
Instead, files optimized for each of the various connection
speeds must be made available for users to select themselves.
Also, the HTTP-based approach does not allow for live
streaming audio or video presentations because complete files
must be stored on the Web server before they can be accessed.
Finally, HTTP does not make efficient use of server resources,
and as a result doesn't perform well under heavy server
loads.
But for sites serving no
more than a handful of simultaneous streams at any given time,
this is a great way to add streaming audio and video features
to your Web site without incurring extra costs.
Here are instructions
for preparing RealAudio or RealVideo files for use on the
Web.
- Copy your encoded files (files
with the .ra, .ram, .rm or .rpm extension) to your World
Wide Web server.
- Use a text editor (such as
Notepad or SimpleText) to create a metafile containing a URL
to your file. For example, the contents of your metafile
should be in the following form: http://hostname/path, where
hostname is the name of your World Wide Web server. For
example: www.real.com
- Save your metafile as a text
using a .ram file extension.
- In your HTML document, reference
the metafile in a hyperlink. For example:
<A
HREF="filename.ram">
<A
HREF="http://hostname/file.rm"> You can use relative or complete paths. If
you use complete paths, you must include both the hostname
and the complete path. For example:
<A
HREF="http://www.real.com/home/welcome.ram">
- When a user clicks on the link,
the streaming file(s) begin to download. The RealPlayer
begins playing after a few seconds; it does not need to wait
for the entire file to be downloaded.
With HTTP streaming and
the right encoding and optimization tools, any Web developer
has the ability to create and serve on-demand real-time audio
and video. |