Streaming Real Media
Virginia Commonwealth University supports the use of streaming Real Audio (.ra) and Real Media (.rm) files. This page describes what you need to do to make your Real Audio/Media available to a web browser.
How it works
The following diagram shows that there are three files involved in displaying a streaming media file: an HTML Page stored on a web server (e.g. www.vcu.edu), a RAM page stored on a web server, and the Real Audio/Media file (.ra or .rm) stored on the Video Server. The web browser displays a web (HTML) page, which contains a link to a special Real Media Metafile (RAM file) (explained below). The RAM file contains the links to the .ra or .rm file.
Step 1: Transfer the Media Files to the Video Server
First you need to upload your Real Audio/Media file (.ra or .rm) to the video server (video.vcu.edu) using SSH (Secure Shell) software. You can obtain the SSH software for Windows 95/98/2000/NT for free. To learn how to transfer files to the server see the SSH Instructions. Please note that the video server does not act as a web server and a web server account is needed to link to your video files.
Step 2a: Create a link to the video using a mount point
If you are streaming a media clip through Blackboard you must use this
method.
To easily stream Real Media you can use a feature of the server called "ramgen."
This is a simple url that points to your file.
http://video.vcu.edu/ramgen/accountid/filename
For example, if Joe User had an account of the video server of 'juser' and had ftp'd a Real Media file called 'chapter1.rm' to the video server, then the link to the streaming video file would be:
http://video.vcu.edu/ramgen/juser/chapter1.rm
Step 2b: Create the RAM file
This method will not work in Blackboard; please refer to Step 2a.
For more control over the streamed media you can use a .ram file. The .ram file is what
enables the file to be streamed from the website as opposed to having your
computer try to download the whole thing. The .ram file only contains the
address of your .ra or .rm file which directs the real player to stream from
that address. The RAM file is a simple text file that links
the HTML Page to the Real Media file.
Use Notepad to create this file and save it with the appropriate extension. If the .txt extension does not dissapper then you can rename the file when you upload it using your FTP program. To edit this file you should right-click the file and slect "open with" then select notepad.
It usually contains three lines of data:
rtsp://video.vcu.edu/accountid/filename --stop-- pnm://video.vcu.edu/accountid/filename
For example, if Joe User had an account of the video server of 'juser' and had ftp'd a Real Media file called 'chapter1.rm' to the video server, then his RAM file would be
rtsp://video.vcu.edu/juser/chapter1.rm --stop-- pnm://video.vcu.edu/juser/chapter1.rm
As you can see, there are two links to the same file. RealSystem G2 uses the RTSP protocol for streaming files. RealSystem 5.0 and all other pre-G2 players uses the PNM protocol for streaming files. The former improves the streaming process by delivering higher quality audio and video to audiences and by providing content creators with greater flexibility.
Hence, a RealSystem G2 player uses the RTSP protocol to stream the file. A pre-G2 RealSystem player will ignore the RTSP line and use the PNM protocol to stream the file.
Step 3: Create the link to the RAM file
Linking to a RAM file is virtually the same as linking to any other file or web site.
<a href="fileURL">Link Name</a>
For example, if the RAM file is called 'chp1.ram' and is in the same directory as the HTML page, then the link would be
<a href="chp1.ram">View Chapter 1 Video</a>
Embedding Real Player into a webpage
You can include a movie or an audio file in your web page. This makes the movie play when the page loads. The Real Player program does not come up on the screen. The code neccessary to embed a windows movie is:
Click here for the text file with the code.
Click here for an example of an embedded movie: Embedded real Player
