What is MPEG-DASH | Video: Formats/Technology | WebTV Solutions

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What is MPEG-DASH?

DASH stands for Dynamic Adaptive Streaming over HTTP. It is a streaming standard introduced by the Moving Picture Expert Group (MPEG), in an attempt to solve the complexities of media delivery to multiple devices with a unified common standard.

Since Flash support is coming to an end (sooner than later) the real importance of DASH is for HTML5 streaming.

The importance of DASH for desktop PC
As explained above, Flash support is coming to and end very soon and, when that finally happens, the only possible way to playback streaming video on desktop PCs is with Browsers that support DASH and HTML5.

The importance of DASH for Mobile devices
Unlike desktop, streaming video on mobile devices has been achieved by using a -proprietary- streaming technology similar to DASH which was developed by Apple (HLS). HLS is supported by iOS, its support in Android began in version 3 (with serious issues), then improved on 4.x.
The importance of DASH for mobile devices is standarization across platforms and devices (not only mobile ones). By having a unified -open- streaming standard then it wouldn't be necessary to use different delivery/streaming technology for Mobiles, Desktops or any other kind of devices.

Codec agnostic
A serious problem that MPEG DASH doesn’t solve is the HTML5 codec issue: DASH is codec agnostic. This means that it does not enforce the use of H.264 or WebM and since the codec support varies across Browsers then content must be encoded in multiple codecs in order to achieve the best possible compatibility.

Browser support
As for today, many modern Browsers support DASH through the HTML5 Media Source Extensions (MSE):
• Chrome (desktop) >= v30
• Safari (desktop) >= v8
• Firefox (desktop) >= v42
• Edge
• IE 11 on Windows 8
• Android >= v4.0 with Chrome
• Windows Phone 8.1

DASH support in WS.WebTV

DASH is supported in WS.WebTV since version 1.9, through the StreamClip extension and powered by Dash-Industry-Forum dash.js: https://github.com/Dash-Industry-Forum/dash.js.