Synchronized Multimedia In addition to basic audio and video content, RealVideo system allows you to create real-time on-demand multimedia presentations using the RMMerge tool (Windows or UNIX). These presentations can be as simple as a narrated slide show of your home page or as intricate as a multi-frame training program that the viewer controls. RealVideo System includes the ability to synchronize World Wide Web pages with audio. Thus the audio can be used as a "time line" to display new pages or frames in the Web browser or to update its content. This enables the creation of Internet slide shows, presentations, guided tours and site walk-throughs. A user can have full random access (fast forward and rewind), and the Web browser content is synchronized with the audio. RealVideo System stores the information for the synchronized events in a file with a .rm file extension. RealServer streams audio and event information to RealPlayer. The event information is streamed to RealPlayer, and in turn RealPlayer sends Web page information to the Web browser telling it to update the page's content. Another way to create a synchronized multi-media presentation is using RealPlayer Plug-in. However, since sending the Web browser to a new URL unloads RealPlayer Plug-in when the HTML page is unloaded, it is best to create separate frames for RealPlayer Controls and for the changing images. For more information about frames, refer to Frames: The Basics. Creating an Events File Using Synchronized Multimedia with Bandwidth Negotiation Frames: The Basics Synchronizing Frames and Audio and Video Creating an Events File Creating a synchronized multimedia event using the RMMerge tool is a three-step process: Use a text editor to create an input file specifying the display time for each URL, title, author or copyright event. Use the RMMerge tool to generate a binary file from the text input file by typing the following command: rmmerge -f rmevents.dll event.txt output.rm where: event is the text file created in step 1 output is the .rm file that contains these events Merge your new events .rm file with an audio or video file using the following command: rmmerge output.rm audio/videofile final.output.rm where: output is the .rm file created in the previous step. audio/video is the file resulting from the merge. Creating the Input File Begin by creating a list of the URLs, titles, authors, or copyrights that you want to be shown during your presentation and the times within RealAudio or RealVideo clip when they should be displayed. The syntax for each entry should follow the format (with a space between each part of the command): u starttime endtime EventURL i starttime endtime Title a starttime endtime Author c starttime endtime Copyright where: u stands for URL event; each line starts with the letter u i stands for title; each line starts with the letter i a stands for author; each line starts with the letter a c stands for copyright; each line starts with the letter c starttime is the time into the clip when the new event is shown. endtime is the time into the clip when that event ends. Event URL (generally beginning with "http:" or "file:") is the Internet address for that event (usually an HTML document). The time for starttime and endtime is: [[[days:]hours:]minutes:]seconds[.tenths] The lines of the input file must be in ascending order of start time. The end time should be at least one tenth of a second before the start time of the next event. The following example shows how an input file might look: u 00:00:10.0 00:00:59.9 http://www.real.com/ u 00:01:00.0 00:02:00.0 http://www.mysite.com/ page2/ This input file tells RealPlayer to send the Web browser to the RealNetworks home page ten seconds into the audio clip. One minute into the audio clip, the Web browser displays a page from "www.mysite.com". The input file may also contain comment lines beginning with the # symbol. These comment lines are ignored by the event creation tool and are a good way to document the date that the file was created and the type of information found on each page. Using Synchronized Multimedia with Bandwidth Negotiation When you deliver a Synchronized Multimedia presentation using Bandwidth Negotiation, you can choose to deliver the same event for all encoding formats, or you can choose to deliver different events for each encoding format. You can create a single synchronized multimedia presentation for multiple formats, or you can create a different multimedia presentation for each encoding format. If you are working with previously created content, you can continue to use the previous method to create presentations. For new content, refer to Synchronized Multimedia. For general information about Bandwidth Negotiation, refer to Bandwidth Negotiation. Frames: The Basics Some Web browsers support a feature which allows the browser window to be divided into multiple regions. Each region is called a frame and can display a separate URL such as a graphic or document. For an introduction to frames visit Netscape's Web site at: http://www.netscape.com If you are unfamiliar with frames the following two sites provide a good introduction: Understanding Frames http://www.netscape.com/navigate/understanding_frames.html Frames: An Introduction http://www.netscape.com/assist/net_sites/frames.html Frame Document A frame document describes the sub-HTML documents or frames that make up a window. The basic structure of a frame document is similar to that of a normal HTML document except that the FRAMESET tag replaces the BODY tag. Each frame is defined by the FRAME tag. In order to effectively use RealVideo, each FRAME tag needs the SRC and NAME attributes. The SRC points to the URL to be displayed in the frame. The NAME attribute assigns a name to the frame so that it can be targeted by links in other documents. The example below shows a simple frame document that would create two frames: <HTML> <FRAMESET ROWS="105,*"> <FRAME SRC="banner.html" NAME="banner"> <FRAME SRC="lyrics.html" NAME="Lyric"> </FRAMESET> </HTML> Synchronizing Frames and Audio and Video Frames and RealAudio and RealVideo content are synchronized in the same way that a regular Web page and RealAudio and RealVideo content are synchronized: a .rae file. The difference lies in the addition of the targeted frame name to the text file that is used to create the .rae file. The syntax for each entry should follow the format: u starttime endtime &&framename&&EventURL where: u stands for URL event (each line starts with the letter u) starttime is the time into the clip when the new event is shown. endtime is the time into the clip when that event ends, && is a delimiter. framename is the frame name as specified in your frame document Event URL (generally beginning with "http:" or "file:") is the URL for that event (usually an HTML document). The time format is: [[[days:]hours:]minutes:]seconds[.tenths] The lines of the input file must be in ascending order of start time. The end time should be at least one tenth of a second before the start time for the next event. The example below shows an .rae input file for a Web site that displays lyrics as a song plays. Each verse is displayed within a frame called Lyric. u 00:00:10.0 00:00:35.0 &&Lyric&& http://www.songs.com/ver1.html u 00:00:35.0 00:00:50.0 &&Lyric&& http://www.songs.com/ver2.html NoteYou cannot use frames within a presentation using RealPlayer. You can only use frames within a multimedia presentation using the Plug-in or ActiveX. More Information on Frames A complete discussion of frames is beyond the scope of this manual. For more information on frame attributes and syntax and on targeting windows consult the following Web pages: Frames -- Syntax http://www.netscape.com/assist/net_sites/frame_syntax.html Targeting Windows http://www.netscape.com/eng/mozilla/2.0/relnotes/demo/target.html

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