The Player's the Thing...But So Is The Codec, Format, and Protocol
At TV 2, Pedersen noted that the station had just launched Smooth Streaming, so hard evidence wasn’t yet available. From the initial comments he’s heard from viewers, however, he says, "It is finally possible for [users] to watch TV on their computers without having to deal with the word ‘buffering.’ I am absolutely positive that this will extend both viewing time and frequency." TV 2 broadcasts up to eight streams of its shows, from 320x180 at 300Kbps to 720p at 6Mbps.
Goldstein added that his network monitored "viewer engagement" of the show The Hills after implementing Flash’s Dynamic Streaming and found that those watching the higher-quality streams watched the program longer. Currently, for new shows shot in HD, MTV distributes seven encoding levels, ranging from 350Kbps to 1.8Mbps, though older SD-only shows were streamed using five levels.
As mentioned, multiple streams are also integral to MLB’s strategy, which involved up to 10 different streams ranging from 164Kbps to 3Mbps. Inzerillo says one of the most popular levels was the 720p stream encoded at 2.2Mbps, which was quite sustainable using the Swarmcast-driven HTTP packets.
Managing Costs in a Multiple Stream WorldOne of the perceived downsides of adaptive streaming is an increase in bandwidth costs. Goldstein recommends managing costs via "size-appropriate encoding," or matching the stream to the viewer’s window size. For example, when I watched an Eminem video with an embedded window in a browser, the Flash Player measured the download speed at more than 6Mbps, but it maintained the video stream at 650Kbps, which was the maximum available for that window size.
MTV MTV manages cost with size-appropriate encoding, which matches theencoding parameters to the window size. When I changed over to full screen, the Max Video Stream jumped to 1.4Mbps. A few moments later, the Flash Media Server started sending a 1.4Mbps stream. MTV also matches encoding resolution to the target display size because it’s a waste of bandwidth to send a larger resolution stream and then scale it down in the player.
If cost is a primary issue, Inzerillo recommends using adaptive streaming to protect the downside and maintain an acceptable viewer experience. For example, if you’re currently distributing at 600Kbps, consider adding a 400Kbps stream so that viewers who can’t consistently retrieve a 600Kbps stream can still receive a stream that plays smoothly.
If you see adaptive streaming in your future, be on the lookout for products using H.264 Scalable Video Coding (SVC), a standards-based approach with one key theoretical advantage over any current adaptive bitrate technologies: Specifically, SVC can serve multiple streams from a single encoded file. In MTV’s case, this would mean encoding one stream rather than seven and administering one stream within the delivery CDNs rather than seven.
There are certainly lots of questions about when and if SVC will actually make it to the market and if the theoretical advantages will translate to real ones. Still, keep it on your radar screen. I think it will make a big splash in 2010.
What About the iPhone?
As mentioned before, one new technology that made a big splash in 2009 was Apple’s HTTP Live Streaming to iPhones. According to paidContent.org, during the early rounds of the 2009 playoffs, MLB served an average of 350,000 streams per postseason game, with 314,000 directed toward computers and 36,000 to iPhone and iPod touch viewers.
If you’re considering iPhone/iPod touch delivery, understand that it’s a totally separate medium with unique encoding and serving requirements. For example, if you’re currently streaming via Flash or Silverlight and want to add the iPhone, you’ll likely have to acquire separate encoders to produce the iPhone-targeted streams; you’ll also likely require separate hosting and server requirements. Still, whether you’re delivering directly or via an OVP, if streaming video is mission-critical to your enterprise, you should plan to address the iPhone market sooner rather than later.
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