WebViewer

WebViewer is a desktop client application which permits the playback of certain enabled live video streams and video archives with synchronized sides and TabletPC ink annotations. It embeds Windows Media Player and contains a subset of Classroom Presenter functionality to display the audio, video and presentation.

ConferenceXP WebViewer was designed to support archives originating from ConferenceXP.

Downloads/Revision History

Installation notes

To install, simply verify that your system meets the requirements below, then run the installer (MSI file).

WebViewer Archives

Here are some sample archives containing CXP WebViewer presentation data:

Autumn 2006 CSEP 590a: http://www.cs.washington.edu/education/courses/csep590a/06au/lectures/
Spring 2006 CSEP 505: http://www.cs.washington.edu/education/courses/csep505/06sp/lectures/
Winter 2006 CSEP 590tu archives: http://www.cs.washington.edu/education/courses/csep590/06wi/lectures/

Troubleshooting and Known Bugs

A couple of problems have been reported with archive playback which seem to be the result of IE holding corrupt data in its cache. Some of us have seen a situation where clicking on WBV files in IE launches WebViewer, but fails to open the media. One user reported no ink playback. Another user was unable to jump to a slide using the table of contents. The workaround in all cases was to use IE Tools menu->Internet Options, and delete Temporary Internet Files.

During a live presentation, if a WebViewer user launches a stream after annotations or slide size changes have been made, the missed presentation data will never be available to the user.

If there is a lot of annotation data in a presentation, WebViewer can consume a lot of memory and CPU. If system resources are constrained, the rendering of ink will become delayed.

If the optional navigation buttons are enabled, clicking the forward jump too rapidly, especially in a streamed playback scenario, can cause the player to spuriously flip into stopped state.

Playing back from the local disk on a system with Windows Media Player v11, there is a minor problem with navigation using the table of contents. When you click on a table of contents item you may see the media positon jump to a position as much as 10 seconds earlier than expected. For now we recommend WMP 10.

To report bugs: First enable logdisplay and/or logfile in the WebViewer config file (see below), then reproduce the problem, and send the information to the address at the bottom of this page. Reporting of bugs is encouraged.

User Notes

Configuration Options

In the WebViewer application directory, there is an XML formatted text file named "WebViewere.exe.config" which may be used to influence aspects of WebViewer's operation. The following keys are observed at startup:

CXPWebViewer.logfile May be set to true or false. A true value causes a file "diagnostic_log.txt" to be created in the application directory. Into this file will be written details of WebViewer's operation.
CXPWebViewer.logdisplay May be set to true or false. A true value causes WebViewer's diagnostic messages to be displayed in a scrolling text box below the table of contents on the main form.
CXPWebViewer.BackgroundColor May be set to a string matching any of the colors recognized by the .Net Framework. Most common color names are recognized. If not set, "Wheat" is the default. This color will be used as the background color of the slide display.
CXPWebViewer.navbuttonsenabled. If set to true, this option will enable two additional forward and backward navigation buttons. The buttons cause the player to jump forward and backward by a fixed interval which can be customized (see next entry).
CXPWebViewer.jumpincrement. If navbuttonsenabled is set to true, this value will be interpreted as the number of seconds to jump when the buttons are clicked.

Supported Media

WebViewer may be used to play any media file supported by Windows Media Player version 9, however the value of using WebViewer is only realized if the media is accompanied by data representing presentation events such as slide transitions and annotations. There are three general scenarios using such data for which WebViewer provides slightly different levels of support:

Live Presentation. If WebViewer is used to view a live presentation, the data used to build the slide view will be embedded directly into the Windows Media stream. In this case the user does not have the ability to change position in the stream, and the Table of Contents will be blank and unused.
Archived Presentation without Preloaded Data. In this scenario, the Windows Media content has been archived and indexed, and the archive may contain Markers to support a Table of Contents, but the presentation data has not been made available for preloading by WebViewer. In this case the user may change position within the archive (by means of markers or slider), but presentation state may not be accurate after the position change operation.
Archived Presentation with Preloaded Data. This is the preferred way to prepare an archive for WebViewer. In this scenario, an ASX file (Windows Media Metadata) will be used to open media. The ASX file will refer WebViewer to presentation data for the archive, and this data will be loaded. If the user changes position within the archive, the preloaded data is used to restore accurate presentation state for the new position. In this scenario, any embedded presentation data will be ignored.

Custom File Type

Beginning with WebViewer 1.9.5, files ending with name extension WBV may be used to launch WebViewer and open media in a single operation. The WBV file is a simple XML format containing a href to Windows Media content. For Example:

Source

WebViewer Source 1.9.2.zip

WebViewer 1.0 Source.zip

Build Requirements:

Visual Studio .Net (2003 for 1.9.2)
Tablet PC SDK v. 1.5 or later
Windows Media Player v. 9

Archive Authoring

ConferenceXP implements a high quality interactive distributed classroom or distributed meeting by leveraging Internet2 or other high bandwidth, multicast-enabled network. Live streaming and archiving of ConferenceXP events can be accomplished with Windows Media Gateway. A more complete archiving system for ConferenceXP events is provided by the ConferenceXP Archvie Service. This service stores all event data in a SQL Server database. This data can then be post-processed using the CXP Archive Transcoder to produce AV and presentation data files for streaming and download.


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Introduction