Using command markers in streaming media files

Command markers add interactivity to media streamed over the Internet by inserting metadata into streaming media files. As your file plays, any number of other actions can be programmed to occur. These commands are a part of the Windows Media Audio, Windows Media Video, and RealMedia streaming formats. Most frequently, these actions add text or open a related Web site.

Command markers can also indicate when an instruction (function) occurs in a WAV file being used in a radio broadcast environment (Scott Studios data). The following two sections define the markers for both streaming media and Scott Studios files.

Notes:

While streaming, media files can be played on any hard drive, CD drive, or DVD drive. They require a special streaming media server (provided by your ISP) to stream properly across the Internet.

Windows Media Player 9 and later will ignore metadata commands unless the Run script commands when present check box is selected on the Security tab of the player's Preferences dialog. Be sure to instruct your audience to select this check box before playing your file.

Defining streaming media commands

In a streaming media file, command markers can be used to display headlines, show captions, link to Web sites, or any other function you define. Some command types are exclusive to either the Windows Media files or RealMedia files.

Command

Player type

Description

URL

Windows Media

Indicates when an instruction is sent to the user’s Internet browser to change the content being

 

and RealMedia

displayed. With this command, you enter the URL that appears at a specific time during the file’s

 

 

playback.

 

 

 

Text

Windows Media

Displays text in the captioning area in Windows Media Player located below the video display area.

 

 

You enter the text that appears during playback.

 

 

Note: To view captions during playback in Windows Media Player 9 or later, choose Captions

 

 

and Subtitles from the Windows Media Player Play menu, and then choose On if Available from

 

 

the submenu.

 

 

 

Title

RealMedia

Displays the entered text on the media player’s title bar.

 

 

Note: When rendering Windows Media files, title information is based on the settings in the

 

 

Summary window (View > Metadata > Summary Information) or the Index/Summary tab of

 

 

the Custom Template dialog. The summary information from the Summary window will be used if

 

 

information has been specified in both places.

 

 

To view this information during playback, choose Now Playing Options from the Windows Media

 

 

Player View menu and select the items you want to display.

 

 

 

Author

RealMedia

Displays the entered text (author’s name) when a user selects About This Presentation from the

 

 

RealPlayer shortcut menu.

 

 

Note: When rendering Windows Media files, title information is based on the settings in the

 

 

Summary window (View > Metadata > Summary Information) or the Index/Summary tab of

 

 

the Custom Template dialog. The summary information from the Summary window will be used if

 

 

information has been specified in both places.

 

 

To view this information during playback, choose Now Playing Options from the Windows Media

 

 

Player View menu and select the items you want to display.

 

 

 

Copyright

RealMedia

Displays the entered copyright information when a user selects About This Presentation from the

 

 

RealPlayer’s shortcut menu or Properties from the Windows Media Player shortcut menu.

 

 

Note: When rendering Windows Media files, title information is based on the settings in the

 

 

Summary window (View > Metadata > Summary Information) or the Index/Summary tab of

 

 

the Custom Template dialog. The summary information from the Summary window will be used if

 

 

information has been specified in both places.

 

 

To view this information during playback, choose Now Playing Options from the Windows Media

 

 

Player View menu and select the items you want to display.

 

 

 

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