Your SlideShare is downloading. ×
MPEG-DASH Conformance and Reference Software
Upcoming SlideShare
Loading in...5

Thanks for flagging this SlideShare!

Oops! An error has occurred.


Saving this for later?

Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime - even offline.

Text the download link to your phone

Standard text messaging rates apply

MPEG-DASH Conformance and Reference Software


Published on

Published in: Technology

  • Be the first to comment

No Downloads
Total Views
On Slideshare
From Embeds
Number of Embeds
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

No notes for slide


  • 1. MPEG-DASH Conformance and Reference Software ISO/IEC 23009-2 Christian Timmerer Alpen-Adria-Universität Klagenfurt (AAU)  bitmovin GmbH   , 105th MPEG Meeting, Vienna, Austria July 2013
  • 2. Outline • Introduction and overview • Media presentation conformance • DASH access client reference software: libdash • Sample software – Clients: sample player, GPAC – Segmenter: MP4Box • Summary July 2013 2Christian Timmerer (AAU/bitmovin)
  • 3. Introduction • Conformance and reference software of MPEG-DASH serves three main purposes: – validation of the written specification; – clarification of the written specification; and – conformance testing for checking interoperability for the various applications against the reference software which aims to be compliant with ISO/IEC 23009 • ISO/IEC 23009-2: media presentation conformance, test vectors, DASH access engine reference software, sample software July 2013 3Christian Timmerer (AAU/bitmovin)
  • 4. Overview • Media presentation conformance – MPD validator: xlink, schema validation, add’l validation rules – Segment conformance: check ISOBMFF, M2TS against DASH specification – Dynamic service validator: dynamic updates of the MPD • DASH conformance sequences • DASH access client reference software – libdash: access to information contained in the MPD + schedule download of segments • Sample software – Sample player: utilizes libdash, GUI, manual adaptation logic – GPAC player: integrated player or embeddable DASH engine – MP4Box segmenter: create segments + MPD based on encoded content July 2013 4Christian Timmerer (AAU/bitmovin)
  • 5. MPD Conformance Free online MPD validation service accessible at July 2013 5Christian Timmerer (AAU/bitmovin) Resolves all W3C XLINK attributes as defined in MPEG-DASH Part 1 Performs the XML validation (i.e., well-formed and valid) against the MPD schema as defined in W3C XML and W3C XML SCHEMA Performs the Schematron validation as defined in ISO/IEC 19747-3 according to the rules defined in MPEG-DASH Part 2
  • 6. libdash • MPEG-DASH Part 1 defines XML-based MPD and segment formats (M2TS, ISOBMFF) – MPD reflects the DASH data model providing HTTP URLs to downloadable segments • Adaptation logic is deliberately excluded from the specification and left open for industry competition • libdash provides the following features: – Object-oriented interface into the MPD – Access information within MPD and schedule download of segments – External interfaces: DASH streaming control (incl. adaptation logic), segment parser, media player – deliberately not implemented: may vary across use cases, deployments, and go beyond what is normatively specified • libdash has full standard support, well-defined interfaces, and enables integration within a media ecosystem ➜ libdash is an enabler! July 2013 7Christian Timmerer (AAU/bitmovin)
  • 7. Sample Player • Qt-based cross-platform GUI + ffmpeg based on libdash • Works with conformance bitstreams, DASH-IF test vectors, and major DASH datasets July 2013 Christian Timmerer (AAU/bitmovin) 8 Select available MPDs Video content Download MPD, start/stop streaming Interactive seamless switching of AdaptationSets and Representations Segment, frame, audio, video buffer
  • 8. GPAC Players for DASH • Open Source project • Integrated player or embeddable DASH engine – Multi-platform: desktop, mobile – Playback of a very large subset of DASH conformant content • M2TS and ISOBMFF segments • "static" or "dynamic" presentations • Live, Main, OnDemand and Simple profiles – Support for quality changes • Interactively or automatically (bandwidth estimation and limitation) July 2013 9Christian Timmerer (AAU/bitmovin)
  • 9. GPAC MP4Box for Segmenting • Conformant generation of – Media files (ISOBMFF, M2TS) – MPD (all profiles) • Support for several MPD syntax options – SegmentList, SegmentTemplate, SegmentTimeline • Automatic mapping of the inputs into adaptation sets, representations, groups, assignment of roles – Based on the content characteristics • Flexible generation of segments and subsegments with possible indexing, RAP alignment, and bitstream switching features • Generation of "dynamic" MPD and segments and updates from pre-recorded content July 2013 10Christian Timmerer (AAU/bitmovin)
  • 10. Summary • MPEG-DASH conformance and reference software available and accessible via MPEG SVN repository – Includes conformance bitstreams for MPDs, segments, and combinations thereof – libdash + sample player: – GPAC: • Additional useful resources – DASH dataset ( full-length movies w/ different segment sizes, spatial resolutions, bitrates, and genre – Distributed DASH dataset ( one dataset distributed across seven sites (Klagenfurt, Paris, Prague, Torino, Crete, Delft, Taiwan), usage of multiple BaseURL elements – DASH Industry Forum ( DASH-AVC/264 interoperability points, identifier repository, reference client (dash.js,, sample players, clients July 2013 11Christian Timmerer (AAU/bitmovin)