Adobe previewed some new streaming video capabilities of its Flash Media Server at the 2011 National Association of Broadcasters (NAB) trade show, including new compatibility with iOS devices like the iPad. Instead of getting Steve Jobs to relent on his "thoughts on Flash," however, Adobe is instead adding HTTP Live Streaming support to Flash Media Server.
HTTP Live Streaming is a protocol that Apple developed to stream live and recorded video using standard HTTP connections instead of the more difficult to optimize RTSP. It uses H.264-encoded video and AAC or MP3 audio packaged into discrete chunks of an MPEG-2 transport stream, along with a .m3u playlist to catalog the files that make up the individual chunks of the stream. QuckTime on both Mac OS X and iOS can play back this format, and it is the only streaming format compatible with the iPhone, iPad, and iPod touch.
Apple submitted HTTP Live Streaming to the IETF in 2009 as a proposed standard, though it doesn't appear that the standard ever moved beyond the draft stage. However, Microsoft quickly added support to its IIS Media Services server, which is used to deliver "smooth streaming" video to Silverlight-based clients. When IIS Media Services detects an iOS device, it instead packages and delivers the content using HTTP Live Streaming.
Adobe added its own HTTP-based streaming feature to Flash Media Server last year. Similar to Apple's solution, it breaks up H.264 video into chunks saved as separate files and sends those files to a client over HTTP. The difference is that its HTTP Dynamic Streaming uses an XML-based manifest file (instead of a plain-text playlist file) and the MPEG-4 fragment container format (.f4f). Also, it's only compatible with Flash or AIR.
Adobe is "committed to developing technologies that simplify broadcast workflows to make it simpler to reach a fragmented lineup of devices," according to senior product manager for Flash Media Server Kevin Towes. Towes noted in a blog post that Adobe is adding HTTP Live Streaming support to Flash Media Server and Flash Media Live Encoder. "By adding support for HLS within the Flash Media Server, Adobe is reducing the publishing complexity for broadcasters who need to reach browsers supporting HLS through HTML5 (such as Safari) or devices where Adobe Flash is not installed."
In other words, instead of trying in vain to persuade Apple to build Flash into iOS, or losing potential Flash Media Server customers to some other iOS-compatible solution, Adobe seems to be implicitly acknowledging that content publishers need Flash-free video streaming.
It's also worth noting that HTTP Live Streaming will also be served to compatible clients on non-iOS platforms, including Safari on Mac OS X. Apple recently began selling its portable computers without Flash pre-installed, and we discovered that running Safari without Flash seemed to increase battery life of the latest MacBook Air as much as 33 percent. While Adobe has claimed to be working on a MacBook Air-optimized version of Flash, perhaps the company decided it was prudent to cover all bases and serve up content to Mac users who are choosing to not install Flash on their systems (yours truly included).
