ITU Workshop on Quality of Service and Quality of
Experience of Multimedia Applications and Services
Haarlem, The Netherlands, 9-11 May 2016
QoE & QoS of Multimedia Services
Joachim Pomy
OPTICOM GmbH Germany
consultant@joachimpomy.de
1
Recommendation G.1080
• Quality of experience requirements for IPTV services
–
–
–
–
user requirements for QoE for IPTV services
defined from an end user perspective
agnostic to network deployment architectures and transport protocols
specified as end-to-end and information is provided on how they
influence network transport and application layer behavior
– QoE requirements for video, audio, text, graphics, control functions
and meta-data are provided
2
Important Definitions
•
•
•
•
•
3.2.1 channel zapping: The act of quickly changing from one channel to another.
3.2.2 clean audio: Audio track of an IPTV service with background sounds
removed.
3.2.3 group of pictures: The group of pictures (GOP) is a group of successive
pictures within a MPEG-coded film and/or video stream. Each MPEG-coded film
and/or video stream consists of successive GOPs. From the MPEG pictures
contained in it, the visible frames are generated.
3.2.4 triple play services: Services that include IPTV, VoIP, and Internet access.
3.2.5 VoD trick modes: Download and streaming video on demand (VoD) systems
provide the user with a large subset of VCR functionality including pause, fast
forward, fast rewind, slow forward, slow rewind, jump to previous/future frame,
etc. These functions are usually referred to as "trick modes".
3
QoE dimensions
QoE
Objective
Subjective
Quality of
Service
Service
factors
Transport
factors
Human Components
Application
factors
Emotions
Figure 5-1 – QoE dimension
4
Service
billing
Experience
Compression artefacts - 1
5
Compression artefacts - 2
6
Compression artefacts - 3
7
Components that contribute to channel zapping time
TV
STB
HG
GWR
FHR
IPTV head end
IPTV channels
Channel zap request
IGMP leave for
previous channel
IGMP query
IGMP leave
IGMP delay
IGMP query
IGMP join to
new channel
Channel
zapping
time
IGMP join
IP multicast traffic
Buffering delay
Decoding delay
G.1080(08)_F8-1
FHR First Hop Router
GWR Gateway Router
8
Video Codecs
• The following video codecs are used for
television applications:
– H.262 (aka. MPEG-2 Video);
– H.264 (aka MPEG-4 AVC or MPEG-4 Part 10);
– SMPTE 421M (aka VC-1, previously known as
VC-9, the standardized version of Windows
Media™ 9);
– AVS.
9
Audio Codecs-1
• Most video service offerings (e.g., those using
MPEG transport streams or similar) are
capable of supporting more than one audio
codec along with a single or sometimes
multiple video encoding schemes
depending on the head-end equipment and
set-top box.
10
Audio Codecs-2
• Example audio formats used for television applications
are:
– MPEG audio layer II (also known as Musicam, used in DVB
systems, and MPEG-1 audio layer 2);
– Dolby digital used in ATSC systems (formerly known as AC3);
– NICAM 728 (European digital format for PAL);
– Advanced audio coding – AAC (either MPEG-2 AAC or
MPEG-4 AAC ([b-ISO/IEC 14496-3], Subpart 4));
– MP3 (MPEG-1 Audio layer 3) used particularly for music
content.
11
Different Frame Types
12
IP packet loss in different frames
13
Packet Loss Requirements
14
… and on the other hand ?
Current P.NATS timeline
14a
Validation source sequences shared among newly formed "cross- Groups formed during Interim Meeting. Effort to be put into
finding long sources that will be split into short sequences.
lab-validation-groups"
th
15 Dec. 2015
Started
th
14b
Validation source sequences available (high-quality SRCs)
14c
Design of validation databases (matrices)
14d
Harmonization of validation phase HRCs
Jan. 11 , 2016 (SG 12
Meeting)
Discussed and agreed at
th
At SG12 meeting Jan. 2016
Started
SG12 meeting, Jan. 11 st
21 2016
Discussed at SG12
Started
st
meeting, 1 review
Not
started
st
th
completed, Jan. 11 -21
2016
Discussions will continue
during Q.14/12 Audio calls
14e
Processing chain updates finalized
14f
Mixing and matching scripts ready
14g
Validation PVSs exchanged
Processing finalised, first version exchanged
15 Validation PVSs checked, kick-off of tests
Final version of PVS made available to test labs, tests can start
16 Submission of validation databases
7 weeks after PVS being available
Final HRC set expected for
29 Jan. 2016
th
Started
Jan. 29 , 2016
Not
th
Feb. 28 , 2016
started
Not
th
Feb. 12 , 2016
started
Not
th
Feb. 28 2016
started
Not
st
April 21 , 2016
started
Could be start of mixing-and-matching process
April 28th, 2016
17 Validation databases checked
18 Winning model(s) selection
Running of mixing-and-matching
th
May 28th 2016
th
th
19 Interim Meeting
Note: SG12 meeting June 7 â€" 16th
May 28 -30 , 2016
19 Optimization (merging) of modules finalized
1.5 months for merging/optimization
,
th
15 July 2016
20 First draft of P.NATS recommendation
Interim meeting, WP2 meeting
SG12 Meeting June 2016
21 Consent on new Rec. P.NATS
Interim meeting, WP2 meeting
Sept. 2016?
15
Not
started
Not
started
Not
started
Not
started
Not
started
Not
started​
Any questions ?
Contact:
Consultant@joachimpomy.de
16