Dynamic Adaptive Streaming over HTTP

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Dynamic Adaptive Streaming over HTTP (DASH), also known as MPEG-DASH, is an adaptive bitrate streaming technique that enables high quality streaming of media content over the Internet delivered from conventional HTTP web servers. Similar to Apple's HTTP Live Streaming (HLS) solution, MPEG-DASH works by breaking the content into a sequence of small segments, which are served over HTTP. Each segment contains a short interval of playback time of content that is potentially many hours in duration, such as a movie or the live broadcast of a sports event. The content is made available at a variety of different bit rates, i.e., alternative segments encoded at different bit rates covering aligned short intervals of playback time. While the content is being played back by an MPEG-DASH client, the client uses a bit rate adaptation (ABR) algorithm[1] to automatically select the segment with the highest bit rate possible that can be downloaded in time for playback without causing stalls or re-buffering events in the playback.[2] The current MPEG-DASH reference client dash.js[3] offers both buffer-based (BOLA[4]) and hybrid (DYNAMIC[2]) bit rate adaptation algorithms. Thus, an MPEG-DASH client can seamlessly adapt to changing network conditions and provide high quality playback with few stalls or re-buffering events.

MPEG-DASH is the first adaptive bit-rate HTTP-based streaming solution that is an international standard.[5] MPEG-DASH should not be confused with a transport protocol — the transport protocol that MPEG-DASH uses is TCP. MPEG-DASH uses existing HTTP web server infrastructure that is used for delivery of essentially all World Wide Web content. It allows devices like Internet-connected televisions, TV set-top boxes, desktop computers, smartphones, tablets, etc. to consume multimedia content (video, TV, radio, etc.) delivered via the Internet, coping with variable Internet receiving conditions. Standardizing an adaptive streaming solution is meant to provide confidence to the market that the solution can be adopted for universal deployment, compared to similar but more proprietary solutions like Smooth Streaming by Microsoft, or HDS by Adobe. Unlike HDS, or Smooth Streaming, DASH is codec-agnostic, which means it can use content encoded with any coding format, such as H.265, H.264, VP9, etc.[6]


MPEG-DASH technology was developed under MPEG. Work on DASH started in 2010; it became a Draft International Standard in January 2011, and an International Standard in November 2011.[5][7] The MPEG-DASH standard was published in April, 2012 but has been revised in 2019 as MPEG-DASH ISO/IEC 23009-1:2019.

DASH is a technology related to Adobe Systems HTTP Dynamic Streaming, Apple Inc. HTTP Live Streaming (HLS) and Microsoft Smooth Streaming. DASH is based on Adaptive HTTP streaming (AHS) in 3GPP Release 9 and on HTTP Adaptive Streaming (HAS) in Open IPTV Forum Release 2.[8][9] As part of their collaboration with MPEG, 3GPP Release 10 has adopted DASH (with specific codecs and operating modes) for use over wireless networks.[8]

The DASH Industry Forum (DASH-IF)[10] further promotes and catalyzes the adoption of MPEG-DASH and helps transition it from a specification into a real business. It consists of major streaming and media companies, including Microsoft, Netflix, Google, Ericsson, Samsung, Adobe, etc. and creates guidelines on the usage of DASH for different use cases in practice.

MPEG-DASH is integrated in other standards, e.g. MPEG-DASH is supported in HbbTV (as of Version 1.5).[11]


DASH is an adaptive bitrate streaming technology where a multimedia file is partitioned into one or more segments and delivered to a client using HTTP.[12] A media presentation description (MPD) describes segment information (timing, URL, media characteristics like video resolution and bit rates), and can be organized in different ways such as SegmentList, SegmentTemplate, SegmentBase and SegmentTimeline, depending on the use case. Segments can contain any media data, however the specification provides specific guidance and formats for use with two types of containers: ISO base media file format (e.g. MP4 file format) or MPEG-2 Transport Stream.

DASH is audio/video codec agnostic. One or more representations (i.e., versions at different resolutions or bit rates) of multimedia files are typically available, and selection can be made based on network conditions, device capabilities and user preferences, enabling adaptive bitrate streaming[13] and QoE (Quality of Experience) fairness.[14] DASH standard does not specify the adaptive bitrate streaming (ABR) logic.[15] DASH is also agnostic to the underlying application layer protocol. Thus, DASH can be used with any protocol, e.g., DASH over CCN.[16]

On July 27, 2015, MPEG LA announced a call for MPEG-DASH-related patents in order to create a single patent pool for this technology.[17] MPEG LA announced its MPEG-DASH patent portfolio licence. It includes patents that are essential to the MPEG Dynamic Adaptive Streaming over HTTP standard.[18]


MPEG-DASH is available natively on Android through the ExoPlayer, on Samsung Smart TVs 2012+, LG Smart TV 2012+, Sony TV 2012+, Philips NetTV 4.1+, Panasonic Viera 2013+ and Chromecast.[19] YouTube as well as Netflix already support MPEG-DASH, and different MPEG-DASH players are available.[20]

While MPEG-DASH isn't directly supported in HTML5, there are JavaScript implementations of MPEG-DASH which allow using MPEG-DASH in web browsers using the HTML5 Media Source Extensions (MSE).[21] There are also JavaScript implementations such as the bitdash player[22] which support DRM for MPEG-DASH using the HTML5 Encrypted Media Extensions.[23] In combination with WebGL, the HTML5-based adaptive bitrate streaming of MPEG-DASH enables also the efficient streaming of 360° video for live and on-demand use cases.[24]

Clients and libraries[edit]

  • Shaka is the open source dash player from Google.[25]
  • VLC Media Player 3.0 shipped a new client plugin for MP4/MPEG and Live streams.[26][27][28]
  • The cross-platform FOSS multimedia framework GStreamer has supported MPEG-DASH and WebM DASH since at least v1.4.[29]
  • The open-source library libdash[30] is platform independent and runs on mobile platforms such as Android, iOS, Windows Phone.
  • bitmovin provides the bitdash MPEG-DASH player for HTML5 and Flash.[31]


Note that no specific support is required from the server for DASH content, with the exception of Live Streaming.


Content generators[edit]

  • ITEC's DASHEncoder.[26][42]
  • MP4Box and its multimedia framework from GPAC at Telecom ParisTech[43]
  • dashcast from Telecom ParisTech supports MPEG-DASH live streaming[44]
  • MediaGoom MPEG-DASH Packager[45]
  • Bento4 opensource tools and SDK[46]


  • ITEC offers a validation service for MPEG-DASH Media Presentation Description (MPD) files[26]
  • Multiple DASH datasets[47] are offered by the Institute of Information Technology (ITEC) at Alpen-Adria University Klagenfurt,[42][48] the GPAC group at Telecom ParisTech[43] and Digital TV Labs.[49]
  • The BBC has DASH test streams, including DASH over HTTP/2.[50]
  • Widevine DRM supports DASH and Encrypted Media Extensions.[51]
  • Mividi provides software tool for analyzing and monitoring live MPEG-DASH streams.[52]

Supported players and servers[edit]


Currently, DASH streaming is only natively supported on Windows 10 via Microsoft Edge. DASH support on other browsers & operating systems is available via Media Source Extensions.

Product Product Type Platform Live Streaming DRM As of Version Editor
Microsoft Edge Web browser Windows 10 Yes Yes EdgeHTML v12+[53] Microsoft
VLC media player Media player Windows, macOS, Linux, Android, iOS, Windows Phone Yes No v3.0 VideoLAN
MX Player Media player Android Yes Yes v1.9.18
Support for playback of DASH streams is currently unstable.
J2 Interactive
NexPlayer SDK HTML5 (MSE Browsers), Android (mobile, TV, STB), iOS, Chromecast, Windows, Mac, Linux, Tizen, WebOS Yes Yes - NexStreaming
Dash.js SDK HTML5 (MSE Browsers) Yes Yes - Dash Industry Forum
Shaka Player SDK HTML5 (MSE Browsers) Yes Yes - Google
Rx-Player SDK HTML5 (MSE Browsers) Yes Yes - Canal+
bitdash SDK HTML5 (MSE Browsers), Android, LG TVs, Samsung TVs, Xbox One, Universal Windows Platform Yes Yes - Bitmovin
PRESTOplay SDK HTML5 (MSE Browsers), Android, iOS, Windows, Mac Yes Yes - castLabs
THEOplayer SDK HTML5 (MSE Browsers), Android (mobile, TV, STB), iOS, Chromecast, Windows, Mac, Linux, Tizen, WebOS Yes Yes - THEO Technologies NV
Viblast Player SDK HTML5 (MSE Browsers), Android, iOS Yes Yes - Viblast Team
Radiant Media Player SDK HTML5 (MSE Browsers), Android, iOS, Windows, Mac, Linux Yes Yes - Radiant Media Player
Videogular SDK HTML5 (MSE Browsers) Yes Yes -
Fluid Player SDK HTML5 (MSE Browsers) Yes Yes - ExoClick
GStreamer Multimedia framework - Yes Yes 1.4 GStreamer Team
Libdash Multimedia framework - Yes Yes - bitmovin, ITEC Team
GPAC Multimedia framework - Yes Yes - Telecom ParisTech inc.

Patent holders[edit]

Organization Patents[54]
Maxell 15
The Netherlands Organisation for Applied Scientific Research (TNO) 8
Nippon Telegraph and Telephone (NTT) 5
Fraunhofer 4
Columbia University 4
Amotech Co., Ltd. 2
AVerMedia Technologies, Inc. 2
Cable Television Laboratories, Inc. 2
Helios Streaming, LLC 2
JVC Kenwood 1
Lough Corrib Intellectual Property Limited 1


  1. ^ "ABR Logic".
  2. ^ a b "From Theory to Practice: Improving Bitrate Adaptation in the DASH Reference Player, by Spiteri, Sitaraman and Sparacio, ACM Multimedia Systems Conference, June 2018" (PDF).
  3. ^ "dash.js JavaScript Reference Client Landing Page". reference.dashif.org. Retrieved 2020-08-28.
  4. ^ Spiteri, Kevin; Urgaonkar, Rahul; Sitaraman, Ramesh K. (2016). "BOLA: Near-optimal bitrate adaptation for online videos. IEEE INFOCOM, 2016, by Spiteri, Urgaonkar, and Sitaraman, IEEE INFOCOM, April 2016". arXiv:1601.06748. doi:10.1109/TNET.2020.2996964. S2CID 219792107. Cite journal requires |journal= (help)
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  10. ^ DASH Industry Forum
  11. ^ HbbTV Specification 1.5 Archived 2014-07-03 at the Wayback Machine
  12. ^ Overview of Dynamic Adaptive Streaming over HTTP (DASH)
  13. ^ 3GPP Dynamic Adaptive Streaming over HTTP – Standards and Design Principles Archived 2016-08-05 at the Wayback Machine by T. Stockhammer
  14. ^ Towards Network-wide QoE Fairness using OpenFlow-assisted Adaptive Video Streaming
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  16. ^ Y. Liu, J. Geurts, J.-P. Point, S. Lederer, B. Rainer, C. Mueller, C. Timmerer and H. Hellwagner, "Dynamic Adaptive Streaming over CCN: A Caching and Overhead Analysis", In Proceedings of the IEEE International Conference on Communication (ICC) 2013 – Next-Generation Networking Symposium, Budapest, Hungary, June, 2013
  17. ^ MPEG LA Announces Call for Patents to Organize Joint License for MPEG-DASH Archived 2015-08-07 at the Wayback Machine
  18. ^ "DASH Patent Portfolio License Briefing*" (PDF). MPEG LA. 2019-03-04. Retrieved 10 July 2019.
  19. ^ Device Compatibility
  20. ^ The Status of MPEG-DASH today, and why Youtube & Netflix use it in HTML5
  21. ^ HTML5 Media Source Extensions
  22. ^ bitdash DRM Testarea Archived 2015-07-03 at the Wayback Machine
  23. ^ HTML5 Encrypted Media Extensions
  24. ^ 360° Streaming in HTML5
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  27. ^ C. Müller and C. Timmerer, "A VLC Media Player Plugin enabling Dynamic Adaptive Streaming over HTTP", In Proceedings of the ACM Multimedia 2011 , Scottsdale, Arizona, November 28, 2011.
  28. ^ "VLC 3.0 features".
  29. ^ HTTP Adaptive streaming with GStreamer
  30. ^ libdash: Open-source DASH client library by bitmovin Gmbh
  31. ^ bitdash MPEG-DASH Player Feature Details
  32. ^ "Stream over MPEG-DASH with Wowza Streaming Engine".
  33. ^ "DASH Streaming and Playlists".
  34. ^ MPEG-DASH support in Nimble Streamer
  35. ^ Netview and Unified Streaming streaming DASH
  36. ^ "USP Factsheet". Archived from the original on 2015-04-21. Retrieved 2015-04-17.
  37. ^ Akamai Announces Native MPEG-DASH and HDS Support for Live Video Workflows
  38. ^ "Amazon Elastic Transcoder Now Supports MPEG-DASH". Amazon Web Services, Inc. Retrieved 2016-06-03.
  39. ^ MPEG-DASH and streaming reference and resources
  40. ^ bitcodin.com Supported Formats
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  42. ^ a b S. Lederer, C. Mueller and C. Timmerer, "Dynamic Adaptive Streaming over HTTP Dataset", In Proceedings of the ACM Multimedia Systems Conference 2012, Chapel Hill, North Carolina, February 22-24, 2012.
  43. ^ a b GPAC Telecom ParisTech
  44. ^ dashcast of Telecom ParisTech
  45. ^ "MediaGoom. Essential Web Streaming".
  46. ^ Bento4 MPEG DASH Documentation
  47. ^ MPEG DASH Dataset Overview
  48. ^ S. Lederer, C. Mueller, C. Timmerer, C. Concolato, J. Le Feuvre and K. Fliegel, Distributed DASH Dataset, In Proceedings of the ACM Conference on Multimedia Systems (ACM MMSys) 2013, Oslo, Norway, 2013.
  49. ^ "MPEG DASH Test Suite". Archived from the original on 2014-03-07. Retrieved 2013-11-22.
  50. ^ MPEG DASH Test Streams
  51. ^ "The Complete Guide to Widevine". encoding.com. Retrieved 2018-01-11.
  52. ^ "MPEG-DASH Analysis and Monitoring Solution". mividi.com. Retrieved 2019-09-15.
  53. ^ Simplified Adaptive Video Streaming: Announcing support for HLS and DASH in Windows 10 – IEBlog
  54. ^ "DASH Patent List" (PDF). MPEG LA. Retrieved 10 July 2019.

External links[edit]