What is a Ram file?

A Ram file is a text file with the extension .ram (.rpm for playback in a Web page). When a browser receives this file, it launches RealOne Player as a helper application. RealOne Player then requests the clips listed in the Ram file. RealSystem Server can launch RealOne Player without using a Ram file by automatically creating a ram file via Ramgen. In some cases, however, you may need to write a Ram file:

• Streaming from a RealServer not set up to use Ramgen.
• Hosting a RealSystem presentation on a Web server.
• Playing back clips that reside on the user's local computer.
• Opening a clip in a specific RealOne Player mode, such as full-screen.

1. Open any editor or word processor that can save files as plain text. On the top line, enter the full URL of the SMIL file or the media clip. You may need to verify URLs with your RealServer or Web server administrator. As shown below, URLs vary with the playback context.
   
   
   
   • RealServer Streaming

     The following example links to a SMIL file on a RealServer that does not use Ramgen:

     rtsp://realserver.example.com/media/sample1.smil

     To deliver a few clips (but not SMIL files) in sequence, list the URLs in their playback order:

     rtsp://realserver.example.com/media/video1.rm
     rtsp://realserver.example.com/media/video2.rm
     rtsp://realserver.example.com/media/video3.rm
     
     

   • Web Server Playback

     For Web server playback, you specify HTTP and the Web server name, along with the SMIL file or media clip:

     http://www.example.com/media/video1.rm

     To deliver a few clips (but not SMIL files) in sequence, list the URLs in their playback order:

     http://www.example.com/media/video1.rm
     http://www.example.com/media/video2.rm
     http://www.example.com/media/video3.rm

   • Local Playback

     For local playback of clips residing on the user's computer, start the URL with file:// and list clips in their locations relative to the Ram file. For example, the following specifies a clip that resides one level below the Ram file in the media directory:

     file://media/video1.rm

     To deliver a few clips (but not SMIL files) in sequence, list the URLs in their playback order:

     file://media/video1.rm
     file://media/video2.rm
     file://media/video3.rm
     

   
   

2. For a presentation played back from RealServer, you can support earlier versions of RealPlayer (such as RealPlayer 4 or 5) just as Ramgen does with the altplay option. To do this, add the marker --stop-- after the RTSP URL. Then specify the URL for the older clip just as it appeared in your previous Ram file. Here's an example:
   
   rtsp://realserver.example.com:554/media/sample.smil
   --stop--
   pnm://realserver.example.com:7070/media/old_sample.rm

   The second URL specifies the older RealSystem protocol with pnm:// and designates RealServer's PNA port. When RealPlayer connects, it chooses the URL based on its favored protocol. For this reason, you cannot list two URLS that both use the same protocol, whether rtsp://, pnm://, or http://.

    

3. Save the Ram file as plain text with a .ram extension (played in RealOne Player) or a .rpm extension (played in the Web browser).

    

4. Move your Ram file to RealServer or your Web server. Even if all your media clips are on RealServer, you can place the Ram file on your Web server. When the browser receives a Ram file, it turns it over to RealOne Player, which uses the URLs in the file to request clips. Hence the Ram file and the media clips do not need to reside on the same computer.

    

5. For .ram files, link your Web page to the Ram file with an HTML hyperlink such as this:
   
   <a href="http://www.example.com/media/sample.ram">click for video</a>

   For .rpm files, incorporate the link URL in the <EMBED> or <OBJECT> tag. If the Ram file is on RealServer, the URL must not use the ramgen parameter.

Through the Ram file, you can control how RealOne Player initially displays a clip or SMIL presentation. You can play a clip back at double its normal size, for example, or open RealOne Player in its compact mode. To set the starting mode, add one of the following to the end of the Ram file URL:

This example opens a SMIL presentation at full screen:

rtsp://realserver.example.com/media/sample1.smil?screensize="full"

The next example opens a RealVideo clip at double its normal size:

rtsp://realserver.example.com/media/video1.rm?screensize="double"

To include two options, use a question mark before the first option, then separate the second option with an ampersand ("&"). This example opens a RealVideo clip at double size and sets RealOne Player to its compact mode:

rtsp://realserver.example.com/media/video1.rm?screensize="double"& mode="compact"

Guidelines for Setting a Starting Clip Size

If you plan to use double or full-screen mode when launching a clip or presentation, be sure to follow these guidelines:

• Do not use screensize="full" with mode="compact".

   

• RealOne Player may not offer full-screen mode on all operating systems. This mode is generally available on Windows computers with DirectX technology. If RealOne Player for a certain operating system does not offer full-screen mode, it plays the presentation at its normal size.

   

• If RealOne Player offers full-screen mode but has not yet played a clip full-screen, it may first perform a test of this playback mode.

   

• The double and full-size modes work best for high-speed clips. They are not recommended for presentations delivered through modems.

   

• Always test playback when using double and full-size modes to ensure that the visual quality is acceptable. Some types of clips may not scale well.

   

• In full-screen mode, the user can control RealOne Player through a context menu available by right-clicking (on Windows) or holding down the mouse button (on Macintosh).

   

• With RealPlayer 7 and higher, you can launch new windows in double and full-screen modes, too.

You can add a comment to a Ram file by using a pound sign ("#") as the first character on a line. The following example shows two lines commented out of a Ram file:

# Two videos and a SMIL presentation
# streamed from RealServer.
rtsp://realserver.example.com/media/video1.rm
rtsp://realserver.example.com/media/video2.rm
rtsp://realserver.example.com/media/sample2.smil

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