What’s Happening with Flash, DASH and HLS

Which technology will you use in 2015 to reach multiple screens, DASH or HLS? While DASH gets the most attention, HLS is my front-runner, and Flash will still dominate desktops.

Flash has been one of the foundational technologies for streaming media since the VP6 replaced SV3 as the primary codec in 2005. However, when the first iPad was released without Flash in April 2010, many pundits predicted Flash’s demise in favor of HTML5. About 18 months ago, I found the Flash was by far the predominant platform used by premium brands. Though some websites that don’t require digital rights management or adaptive streaming are switching over to HTML5, Flash still dominates broadcast and movie-oriented sites that require both features. 

Two technologies threaten to break this logjam; the standards-based DASH (Dynamic Streaming over HTTP) and HTTP Live Streaming (HLS), the Apple spec used to distribute video securely and adaptively to iDevices. Though billed as somewhat of a panacea, DASH has seen little mainstream support.

In contrast, since HLS is very widely supported by streaming producers, many device manufacturers decided to piggyback off Apple’s efforts and incorporate HLS playback into their products, including all OTT platforms like Roku, Boxee and Google TV and Android 3.0 and above (though Android support has issues). For computer playback, you can use a pre-fab player like the JW Player to add HLS playback to Flash. To be clear, Flash is still required, since the JW Player uses Flash’s H.264 decoder to actually play the video.

So while DASH still gets the most attention, you can now play HLS streams on computers, iOS devices and all OTT platforms. DASH is many months away from being able to make that claim. A recent move by Adobe could also be seen as promoting HLS over DASH.

Specifically, in April, Adobe announced that they were adding HLS support to Adobe Primetime, a cross-platform player productization of multiple Adobe products enabling advertising insertion, digital rights management, integrated analytics, and closed captions. Note that this support was not extended to the free Flash player, but only to companies licensing the Primetime product, which sits above Flash but is a separate product. At the same time, Adobe announced SDKs that would extend Primetime and HLS support to the Android and Apple platforms. Notably, Adobe’s Android SDK supplies an HLS stack that actually works, so HLS functions correctly.

In essence, for companies that can afford Primetime, this makes HLS the preferred adaptive streaming technology, because it can play on computers, as well as mobile and OTT platforms. Though Primetime will support DASH, that support doesn’t extend to the iOS platform for technical reasons beyond Adobe’s control. So even after Primetime supports DASH, Primetime users will still need to support HLS to reach the critical iOS devices.

Will Flash Player Survive?

I read this to say that Adobe was dissing DASH in favor of HLS. My colleague Tim Siglin, in a commentary entitled Will Flash Player Survive?, noted, “Many major player apps and plug-in architectures have plans to support both HLS and DASH, just as Adobe’s Primetime Player will. But curiously, Flash Player will not be one of them.” In a response to one of the comments to the article, Siglin continued, “Jeff, my take is that the underlying Flash architecture, which will be devoid of HLS / DASH, is stagnating—or at least morphing to include less of the video playback capability. That’s a marked change in Adobe’s strategy, hence the question as to whether FP will survive.”

To complete the circle, in a later article, Siglin postulated that HLS’ ubiquity would be DASH’s gain. While I don’t agree with his logic, Siglin was essentially asserting that as more companies used HLS, its technological shortcoming would be more evident. He concludes, “Is it a pipe dream to think that HLS will stumble and falter tomorrow? Yes, probably. Given its antiquated underpinnings, however, it’s a matter of when, not if. For true global broadcasting of live content, HLS has many limitations inherent to its own design, a matter Apple is well aware of.”

I personally think DASH is overrated. Why? First of all, with servers that can transmux to multiple formats, like Wowza, Adobe and Real, it’s just not that hard to support Flash on the desktop and HLS for Apple, with Flash in an AIR app for Android if necessary. So the problem DASH is purporting to resolve just isn’t that significant. Second, until Apple and Google/Android support DASH, which could happen tomorrow, but might never happen, it will only be a partial solution at best.

Now that Adobe has decided to support DASH in Primetime, but not the base Flash Player, it’s clear DASH won’t be available for general use on desktop computers until Adobe changes their policy, or until HTML5 browsers support it natively. While Microsoft and Google are working towards that, there’s no word that Mozilla is. Plus, HTML5 browsers are still only about 70% of the market, with legacy browsers the other 30%, so Flash will still be needed for legacy browsers.

Bottom line? For the next 12-18 months, for those streaming to native players (as opposed to Apps), it’s Flash on the desktop and HLS for iOS devices, with HLS an imperfect solution for Android. Or, you can incorporate technology like the JW Player into your website and use HLS all around. I don’t see DASH having a broad-based impact until 2015 and beyond, if ever. 

About Jan Ozer

I help companies train new technical hires in streaming media-related positions; I also help companies optimize their codec selections and encoding stacks, and evaluate new encoders and codecs.

Check Also

Streaming Media 101: Training for App & Player Development/Testing Professionals

Leave a Reply

Your email address will not be published.