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Video Servers: Live From Your Network

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Our results indicate that VDOLive is at the head of this pack. It offers the flexibility and ease of configuration of stored video on demand and is better integrated with the Web than the other products, an important distinction for any intranet application. IP/TV stacked up well, delivering very good quality video to any number of clients without fear of flooding the network, a benefit of its multicasting approach. Unfortunately, the complexity of administering a multicast service, combined with the quirks of a brand-new product, limit IP/TV's overall utility. Enhanced CU-SeeMe was the weakest of the three, with marginal video quality and overly complex configuration and administration. Still, it is worth considering if you need desktop videoconferencing features to complement your "broadcasts."

VDOnet Corp. VDOLive 2.0

We used the VDO Capture tool to get our comparison clips in two modes, one version at 160x120 pixels at 15 fps, and another at 320x240 pixels and 20 fps. We used 8-KHz sampling, 16-bit mono, for audio since it is the only audio format VDOLive supports.

Then we edited and encoded video with VDO Clip. This tool lets you select the bandwidth you want to encode for--we encoded our comparison clips at the default (28 Kbps) and at the maximum (256 Kbps). Encoding time at the lower target bandwidth was significantly shorter and the resulting file was much smaller, but the video quality was so poor that it wasn't worth the effort. We also used VDO Clip to compress the source video with the Indeo codec so we could use the result to stream video from the IP/TV server, which does not include standalone capture, edi ting and compression tools.

Our comparison tests showed that 256 Kbps is just enough for passable video--but not enough for our larger, original video of 20 fps. We experienced choppy audio and video, and slower frame rates for both the football (6 fps to 10 fps) and talking-head clips (13 fps to 20 fps). Our best results were the 160 x120 clips that were originally captured at 15 fps; on these, video and audio played fairly smoothly and video streamed at close to the original 15 fps for both the talking-head and the action sequence.

The VDOLive installer automatically sets up the server process (VDOSrv) as a Windows NT service and creates a control panel for easy adjustment and viewing of VDOLive server options. The server also maintains a log file that is useful in debugging client/server connections and for monitoring usage. The control panel lets you view token file information, which dictates the limits of your server (maximum bandwidth or maximum number of concurrent streams, for example). You can purchase additional server capacity from VDOnet, which will send you an updated token file.

The VDOLive player can run both in standalone mode and as a Netscape Communications Corp. Netscape plug-in. It also has ActiveX support, should you be interested in Microsoft Corp.'s Internet Explorer 3.0. VDOLive Web integration edges out the other products in this review, but there is certainly room for improvement--finding and setting viewer options isn't as easy as with other viewers we've seen (Xing Technology Corp.'s StreamWorks, for example), and the plug-in isn't as flexible as some others we've tried (most notably, the Real Audio plug-in, which lets you tailor access to the player controls).