Download Internet cloud security: The illusion of inclusion

The MPEG-DASH Standard
for Multimedia Streaming
Over the Internet
Chih-Hsiang Chou
Advisor: Prof Dr. Ho-Ting Wu
Department of Computer Science and Information Engineering,
National Taipei University of Technology
Taiwan, ROC.
Data:13/05/27
Outline
•
•
•
•
•
•
•
Introduction
DASH
A simple case of adaptive streaming
Scope of MPEG-DASH
MPD and Segment format
Additional features
References
2
Introduction
• Problems :
 Delivering video content over the Internet started
in the 1990s with timely delivery and
consumption of large amounts of data being the
main challenge.
 Video streaming service in a heterogeneous
network environment is the variation in the
receiver’s video playback capability.
3
Introduction
• Problems :
 Contention for CPU and I/O resources at the
video server. This may cause variations in the
transmission rate supportable by server.
4
Introduction
• Potential market
 Watching the Olympics live over the Internet?
 Streaming last week’s episode of your favorite TV
show to your game console?
 Watching a 24-hour news TV channel on your
mobile phone?
5
Introduction
• Potential market
 Every commercial platform is a closed system with
its own manifest format, content formats, and
streaming protocols.
 One of the main enablers of this would be an
adopted standard that provides interoperability
between various servers and devices.
6
DASH
• About DASH
 Dynamic Adaptive Streaming over HTTP (DASH),
also known as MPEG-DASH, enables high
quality streaming of media content over the
Internet delivered from conventional HTTP web
servers.
7
DASH
• About DASH
 3GPP - Adaptive HTTP Streaming
 Open IPTV Forum – HTTP Adaptive Streaming
 Adobe – Dynamic Streaming
 Microsoft – Smooth Streaming
 Apple – HTTP Live Streaming
8
DASH
• About DASH Industry Forum
9
DASH
• About DASH Industry Forum
10
A simple case of adaptive streaming
11
Scope of MPEG-DASH
12
Scope of MPEG-DASH
• program timing
• media-content
availability
• media types
• resolutions
• minimum and maximum
bandwidths
• accessibility features
• required digital rights
management(DRM)
• media-component
locations on the network
13
Multimedia Presentation Description
14
Segment format
• A segment is defined as the entity
body of the response to the DASH
client’s HTTP GET.
• A media component is encoded
and divided in multiple segments.
• The first segment might be an
initialization segment containing
the required information for
initialization
15
Segment format
• Each media segment is assigned
 a unique URL
 an index
 start time and duration
16
Segment format
• To enable downloading segments in multiple parts,
the specification defines a method of signaling
subsegments using a segment index box.
• The indexing information of a segment can be put in
the single box at the beginning of that segment, or
spread among many indexing boxes in the segment.
• Different methods of spreading are possible, such as
hierarchical, daisy chain, and hybrid.
17
Additional features
• Switching and selectable streams.
 selecting one audio stream from different languages,
 selecting the subtitles from provided languages,
 dynamically switching between different bitrates of the
same video camera.
• Ad insertion.
• Compact manifest.
• Fragmented manifest.
18
Additional features
• Scalable Video Coding (SVC) and Multiview Video
Coding (MVC) support.
• A flexible set of descriptors.




components’ roles,
accessibility features,
camera views,
audio channels’ configuration
• Quality metrics for reporting the session experience.
19
References
[1] Ranga S. Ramanujan, Jim A. Newhouse, Maher N. Kaddoura,
Atiq Ahamad, Eric R. Chartier, and Kenneth J. Thurber. “Adaptive
Streaming of MPEG Video over IP Networks”, Proceedings of the
22nd IEEE Conference on Computer Networks (LCN’97),
November 1997.
[2] I. Sodagar. “ The MPEG-DASH Standard for Multimedia
Streaming Over the Internet”, IEEE Multimedia, 2011.
20
Thanks for your listening
21