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In the desktop/mobile streaming marketplace, most producers provide two sets of streams; HTTP Live Streaming (HLS) for Apple iOS devices and Android devices and either Flash or Silverlight for the desktop. A number of content and technology companies have gotten together to promote a specification called DASH, which stands for Dynamic Adaptive Streaming over HTTP. Its promise is a single file format for delivery to multiple targets from mobile to OTT, with desktop HTML5 and other segments in between.
Here’s a bit from a Streaming Media article describing a panel discussion on DASH held at Streaming Media West.
The MPEG DASH panel, led by Microsoft’s Iraj Sodagar, who has chaired the MPEG subcommittee on DASH for the past year, was a hot ticket at the 2011 Streaming Media West show, held this week at the Hyatt Regency Century Plaza in Los Angeles. A standing-room only crowd listened to representatives from a number of companies that are on the MPEG-DASH promoters’ group.
“More than 50 companies and 90 experts have contributed to the MPEG-DASH specification,” said Sodagar during his introductory remarks, “including Apple, Adobe, and all the companies represented here today. The proposed first-step of MPEG-DASH is on the verge of completion, and we feel we took best of best practices and incorporated them into the standard.”
So, DASH is a best practices standard that’s broadly supported by technology companies and content producers alike. Companies like Adobe, Microsoft and Apple have agreed to push a common standard. Sounds great, right?
Well, I just finished a “What is” article about DASH, and it turns out that it has more issues than Lindsay Lohan. For example, at this point, we don’t know if there will be a royalty obligation or not, which has prompted Mozilla to comment that they likely won’t support the spec as currently drafted.
Since it’s codec agnostic, the spec does nothing to unify the HTML5 codec mess, so you’d still have to produce WebM and H.264 for full HTML5 compatibility. Neither Adobe nor Apple have publicly stated that they will support the spec once released, and since a specification like this essentially levels the playing ground between these market leaders and their competitors, you have to at least wonder if or when they will.
Now you can add at least the perception of dissension in the ranks to those problems. Last Thursday (November 17), colleague and friend Tim Siglin released a white paper on why fragmented MP4 (fMP4) technology, as used in Adobe HTTP Dynamic Streaming and Microsoft Smooth Streaming, is superior to the MPEG2 Transport Stream approach used by Apple in HLS. The white paper was sponsored by Adobe and Microsoft.
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It’s as if after choosing Joe Biden as his running mate, candidate Obama sponsored a bunch of advertisements as to why he was a stupid choice. And it has to have folks at Apple scratching their head and thinking, “with friends like Adobe and Microsoft, who needs enemies?”
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By way of background, DASH actually supports both approaches, fMP4 and MPEG2 transport stream. But the white paper is essentially a compelling 16-page argument that Apple’s approach sucks and Adobe’s and Microsoft’s is superior. In fact, that’s all correct, but it left me scratching my head. Why fight this battle now?
In their blog posts about the white paper, Microsoft says, “fMP4 files have some distinct advantages over adaptive streaming solutions based on MPEG-2 Transport Streams, such as the proprietary HTTP Live Streaming (HLS) format developed by Apple.” Their note mentions DASH once, right there near the bottom.
Adobe’s blog on the white paper comments, “In a unique cooperation, Adobe with the Microsoft media team, have jointly contributed to a whitepaper sharing our thoughts on Video Streaming file format optimized for online delivery using fragmented MPG4 file format (fMP4) Part 12.” The blog points out that Adobe uses fMP4 in their HTTP-based adaptive streaming technology and also mentions DASH once, right there near the bottom.
In the introduction to his white paper, Siglin states, “Some legacy solutions, such as MPEG-2 Transport Stream (M2TS), lack basic web delivery functions.” He mentions DASH for the first time on page 8, and concludes the white paper by stating, “We expect to see companies like Adobe, Microsoft, Netflix and others advocate for interoperable common approaches to multi-device delivery for consumer/professional content delivery platforms.” Huh? I thought that was what DASH was all about.
Nothing that Siglin says is technically inaccurate; fMP4 is clearly the superior approach. On the other hand, Apple’s HLS is more widely implemented than either Adobe’s or Microsoft’s HTTP streaming technologies and is gaining ground. For example, Revision 3 recently stated that they would use HLS as the basis for live and adaptive streaming for all of their HTML5-based clients. HLS also has other high-profile fans, including Major League Baseball and Hearst Interactive.
All that aside, the supposed promise of the DASH spec is a unified technology standard, one approach that a video publisher can utilize to create once and distribute on multiple platforms. Sure, it has issues, but at this point, all participants would be best served by promoting DASH and making it workable, not promoting technologies within the spec that just happen to be the basis of their own proprietary technologies. The industry needs one clear choice, not business as usual, or in this case, two participants within a spec working group ganging up to bash another.
It’s as if after choosing Joe Biden as his running mate, candidate Obama sponsored a bunch of advertisements as to why he was a stupid choice. And it has to have folks at Apple scratching their head and thinking, “with friends like Adobe and Microsoft, who needs enemies?”
