Webcasting for the Masses
Encoders for LSSPs
Table 2 provides a list of classes of encoding tools and categories. How do you choose between them? Most LSSPs simply broadcast the file or files that you send them with no transcoding. This means that in addition to being compatible with your AV inputs, your encoding tool has to be able to produce the required files in the required formats.
For example, while Multicast Media doesn’t dynamically switch streams during a broadcast, the service does query the player for its current bandwidth before starting playback and send the most appropriate stream to that client. For this reason, when producing for Multicast Media, you might want to encode and upload three different files to the server, perhaps at 700Kbps, 500Kbps, and 300Kbps. If you’re working with an LSSP, the easiest way to supply the necessary compatible streams is to purchase or lease an encoder from the LSSP.
When choosing your own encoder, software solutions such as Adobe Flash Player or Adobe Flash Media Live Encoder typically work well for a single stream but not for multiple streams. The exception is Kulabyte’s excellent XStream live encoder, which can produce up to four simultaneous streams on a sufficiently fast computer. The advantage of using software such as XStream is that you can load it on a notebook computer for portability. You can read my review of the Kulabyte software at www.streaming media.com/article.asp?id=11337.
If you’re producing webcasts from multiple locations, you should also consider portable encoders such as those from Digital Rapids, VBrick, and ViewCast. I’ve worked with the Niagara system (you can see a tutorial that I created at www.streamingmedia.com/tutorials), which offers remote configurability, so an IT person back at the office can help resolve issues encountered in the field. You can also preconfigure the device for one-touch operation in the field, so your webcasting team can plug in the AV source cables and the Ethernet connection and then press the Stream button to start the webcast.
I would guess that the other devices offer similar high-level functionality, but you should check to be sure. The bottom line is that if you’ll be webcasting from multiple locations, you should buy a portable system. In contrast, if you’ll be webcasting from the same location consistently, you can build your own encoding station more affordably using PC cards from ViewCast or Winnov.
The NewTek TriCaster, which is essentially a multicamera switcher with titling and effects, offers a more comprehensive solution. You can produce your event on the TriCaster, send one output to the IMAG presentation system, and send another output out the Ethernet cable to your streaming service provider. The TriCaster can be a great value for event services folks who contract to provide AV and projection and also want to handle webcasting.
Though it’s unlikely that many producers using LSSPs will need a rack-mounted system, I’ve included a product list for general H.264 and iPhone production in the table. I have little experience working with encoders in this class, so I asked MLB’s Joe Inzerillo—who’s charged with broadcasting 2,430 regular season games, plus preseason and postseason—for some tips.
This is Inlet HD’s popular Spinnaker encoder.For Inzerillo’s work with MLB webcasting, reliability is critical. Before choosing Inlet HD’s Spinnaker encoder, he held a "bake off" between multiple vendors, running them for a 5-hour pregame/game/postgame period and analyzing factors such as dropped frames.
While an occasional dropped frame may not be a huge deal on an iPod, an increasing number of his customers are watching the 720p streaming feed on widescreen television sets, and dropped frames are very noticeable encoding artifacts. He recommends that if you can’t get a system in for simulated testing, ask the vendor to put you in touch with clients whose applications and run times are similar to yours.
Inzerillo also noted a significant disparity in the breadth and depth of H.264-related controls made available by each encoding tool. This is significant because he uses different encoding parameters depending upon factors such as whether it’s a day or night game. In addition, his organization provides services to other networks during baseball’s offseason, and encoding parameters that work well for the center field camera in baseball may be totally inappropriate for the side-to-side action in soccer or basketball.
Beyond these considerations, make sure that any encoder you choose can be controlled remotely, preferably with multiple encoding stations viewable from a remote monitoring station at one time. Also look for features such as scheduling, automated failover, and alert notifications.
Though the iPhone encoder market will no doubt grow, the only two vendors shipping products that I could find were Envivio and Inlet HD.
That’s the live video-only market. Now let’s look at the rich media communications market.
Companies and Suppliers Mentioned