Integration of Accessibility Requirements in the Design of Multimedia User Agents Interfaces

Integration of Accessibility Requirements
in the Design of Multimedia User Agents
Interfaces
María González
PhD Program in Computer Science and
Technology
Universidad Carlos III de Madrid, Spain
mgonza1@inf.uc3m.es
Advisor: PhD. Lourdes Moreno

Content
Integration of Accessibility Requirements in the Design of Multimedia User Agents Interfaces
• Introduction
• State of the art
• Proposal
• Validation
• Conclusions and Future Work
• Research and Development projects
• Results´ dissemination
• References
2

Introduction
Motivation (I)
• Multimedia content is being increased at staggering
rates due to Web 2.0, social media, etc  Great
increase in the number and types of users
• Great number of people with disabilities who want to
access this content
3

Introduction:
Motivation (II)
• The failure to comply with accessibility standards
• There are accessibility barriers within:
Content: lack of alternatives like captions or audio
description
Software from which content is accessed: lack of
mechanism to access these alternatives
4
Content Software

• Software Engineering’s (SE)
Methodological design solution
• Human-Computer Interaction’s (HCI)
Standards which study the interaction between a user
and a user agent
Introduction:
Context
Integration of Accessibility Requirements in the Design of Multimedia User Agents Interfaces 5

Introduction:
Objectives
6
• The aim is to offer a design solution of user agents which
delivers video content fulfilling significant requirements
following accessibility standards
A design solution that includes accessibility
requirements in user agents using Model-Based
Development (MBD) is proposed

• Accessibility and disability
• Accessibility standards and regulations
• Media players and accessibility
• User interfaces design
• Related work
• Discussion
State of the art:

• Disabilities which affect Web access:
Visual disabilities
Hearing impairments
Physical disabilities
Speech disabilities
Cognitive and neurological disabilities
Multiple disabilities
Aging-related condition
State of the art:
Accessibility and disability

• Web content
WCAG 2.0 [1] of WAI [2]
 How to make Web content more accessible
Guideline 1.2 Time-based Media
 Standard (ISO/IEC 40500:2012 [3]) since 2012
 Different initiatives in many countries
• User agent
UAAG 2.0 [4] of WAI
 How to make user agents accessible to people with
disabilities
 How to increase the accessibility of Web content
ISO 9241-171 [5]
 Guidance on software accessibility
State of the art:
Standards and regulations (I)

• 21st Century Communications and Video
Accessibility Act (CVAA) of 2010 [6]
 New guarantees to ensure that people with
disabilities do not fall behind as the technology
changes and advances
• EN 301 549 V1.1.1: accessibility requirements
regarding ICT [7]
 Functional accessibility requirements regarding
ICT products and services
• Guidance on Applying WCAG 2.0 to Non-Web ICT
(WCAG2ICT) [8]
Literature review:
Standards and regulations (II)

• Observatory of media player evolution:
 First generation: Flash
 Cross-browser compatibility, power and flexibility in video
playback
 Require a plugin, longer loading time
 Second generation: HTML5 [9]
• W3C Recommendation since October 2014
• Provide accessibility support
• Study of CCPlayer, BBC iPlayer and YouTube [10]
• Media players which support accessibility: JW Player,
BSPlayer, VideoLan, Acorn Media Player or Able Player
Literature review :
Media players and accessibility
11

• Model-based user interface design
Main models [11]:
 Task Model
 Domain Model
 User Model
 Dialog Model
 Presentation Model
Literature review:
User interfaces design
12
General architecture of a model-based user interface design [11]

• Model Driven Development
Levels of abstraction [12]
 CIM
 PIM
 PSM
 (IM) – Code
Vertical transformations [13]
 CIM to PIM
 PIM to PSM
 PSM to Code
Literature review:
Model Driven Architecture [12]

• MBUID Methodologies
TRIDENT [14]
Wisdom [15]
IDEAS [16]
CAMELEON [17]
Literature review:
14
Simplified version of Cameleon Reference Framework [18]

Literature review:
• User Interface Description Languages (UIDL) [19]
USIXML [20]
XIML [21]
UIML [22]
MARIA [23]
15
Independence
Device
Platform
Interaction
modality
Implementing
technology

• Study of accessibility requirements: (Moreno et al., 2008), (Moreno
et al., 2011), (Brunet el al., 2005), etc
• Improve content accessibility: (Federico and Furini, 2012), (Wald,
2011), (Hughes et al., 2015), etc
• User Interface Design approach:
 MDD: (Stanciulescu et al., 2005), (Stanciulescu, 2008), (Link et al., 2008),
etc
 Model-based: (Chesta et al., 2004), (Melchior et al., 2011) , (Rodriguez et al.,
2007), etc
 Adaptive user interfaces: (Miñón et al., 2013), (Peissner et al., 2012), (Giani et
al., 2012), (FP7 Serenoa Project, 2013), etc
• According to the development of a graphical editor: (Mori et al.,
2004), (Creissac et al., 2011), (Montenegro Marin et al., 2011), etc
Literature review:
Related Work
16Integration of Accessibility Requirements in the Design of Multimedia User Agents Interfaces

• Extensive regulation on accessibility
What is the problem?
Literature review:
Discussion (I)
17
Without
accessibility in
content and in
user agent
Failure to
comply
with
standards
- Lack of awareness
- Lack of knowledge
- Not oriented to be
integrated in a development
process

• All these lacks cause
Literature review:
Discussion (II)
18
PhD Proposal
Accessibility
requirements
selection
Abstraction of
requirements
A Design
Proposal based
on models

Proposal:
Methodological approach
1
• List of accessibility requirements
regarding Media Player following
Accessibility Standards.
2
• Model-based Design approaches
using a User Interface
Description Language (UIDL)
3
• Development of a Model-based
Graphical Editor that facilitates
the Design
FinalUserInterface:An
AccessibleMediaPlayer
(C2):WORKSPACE
(C1):ACCESSIBILITY
REQUIREMENTS
19
(C3):PROOF OF
CONCEPT
OBJ.
OBJ.

Proposal (Contribution 1):
Accessibility requirements (I): Native
Name Description Subgroup Source
ISO UAAG 2.0
Play Play the video content Playback 10.8.2 2.11.6
Stop Stop the video content Playback 10.8.2 2.11.6
Pause Pause the video content Playback 10.8.2 2.11.6
Resize Resize the viewports Size 10.5.8 1.8.3
Mute Enable or disable the audio content Volume 10.6.2 1.5.1
Volume Adjust the volume Volume 10.6.2 1.5.1
20
(González-García et al, 2011) INTERACCIÓN 2011, INTERACT 2011

Accessibility requirements (II): Additional
Name Description Subgroup Source
ISO UAAG 2.0
Rewind Delay seconds within a playback Playback 10.8.3 2.11.7
Forward Forward seconds within a playback Playback 10.8.3 2.11.7
Caption Enable or disable captions Alternatives 10.1.3, 10.7.2 1.1.2
Audio Description Enable or disable audio description Alternatives 10.1.3 1.1.2
Size Change the size of the captions Alternatives 10.7.3 1.4.1
Font Change the font of the captions Alternatives 10.7.3 1.4.1
Colour Change the colour of the captions Alternatives 10.7.3 1.4.1
Language Caption Change the language of the captions Alternatives 8.2.1 2.7.1
Language Audio Change the language of the audio
description
Alternatives 8.2.1 2.7.1
Help Help documentation about accessibility
features
Help 11.1.5 3.3.2
Find Search within playback captions Find 2.4.5
21
(González-García et al, 2011) INTERACCIÓN 2011, INTERACT 2011

• Requirements’ modeling using a UIDL and
Cameleon Reference Framework
Model-based Development
• Interaction between a user and a user
agentTask Model
• Interaction elements structure
Abstract User Interface
(AUI)
• Concretize an AUI for a given context of
use
Concrete User
Interface (CUI)
• Operational user interface on a particular
computing platform
Final User Interface
(FUI)
22

Approaches
Cameleon
UsiXML
Task Model
AUI Model
CUI Model
Model driven
graphical
editor
FUI Model
MARIA
Task Model
AUI Model
Adaptation
rules
Model-based
graphical editor
FUI Model

First approach (I)
- UIDL: UsiXML
- Approach: MDD
UAAG 2.0 ISO 9241-171
Abstract
user
interface
Task &
Domain
Final
user
interface
Transformationrules
Requirements
Concrete
user
interface
Model driven
Graphical
editor
Related
Work

• Task Model: CTT notation [24]
 IdealXML [25]
• AUI:
 IdealXML
 Abstract Container (AC)
 Abstract Individual Components (AIC): input, output, control
and navigation
 AUI Relationships
First approach (II)
25
(González-García et al, 2015)
UAIS (Universal Access in the Information Society)
(González-García et al, 2012) DSAI’2012

• CUI:
 Concrete Interactor Objects
 Concrete Relationships
• Model-based Graphical Editor:
 Eclipse [26]: EMF and GMF
First approach (III)
26
In order to guide in the design of accessible user agents
which deliver video content due to problems of the lack of
expertise in MDD, CUI Meta-models of UsiXML and
accessibility => Model driven Graphical Editor

Lab Demo
• FUI:
 From CUI through Graphical Editor
 An example of FUI is presented:
 CUI’s design primitives are mapped into HTML5 methods
First approach (IV)
27(González-García et al, 2013) JUCS (Journal of Universal Computer Science)

Second approach (I)
28
Cameleon
UsiXML
Task Model
AUI Model
CUI Model
Model driven
graphical
editor
FUI Model
MARIA
Task Model
AUI Model
Adaptation
rules
Model-based
graphical editor
FUI Model

Second approach (II)
29
UAAG 2.0 ISO 9241-171
Abstract
user
interface
Task &
Domain
Final
user
interface
Transformationrules
Requirements
Concrete
user
interface
Model-based
Graphical
editor
Related
Work
Adaptationrules
FUI_adaptation_rule_1
- UIDL: MARIA
- Approach: MBD

• Task Model:
 Same Task Model  CTTE [27]
• AUI:
 MARIAE [28]
 Presentations
• Interactor Compositions: grouping, relation, composite
description and repeater
• Interactors: selection, edit, only output and control
• Adaptation rules  ECA rules (action, condition, event)
based on type of access/user groups
Second approach (III)
30
Selection
Single
Choice
Edit
Numerical
Control
Navigator
Control
Activator
LanguageAudio, Size, Color, Font
and LanguageCaption
Volume Find and Help
Play, Stop, Rewind, Forward, Resize,
Mute, AudioDescription and Caption

• Analysis of types of access and user groups with disabilities
Second approach (IV)
Types of access /
groups with
disabilities
Resources necessary to
access
Required accessibility elements (CUI design primitives) Rule
Code
Access visual and
auditory/ simplified
user interface
(essential)
Playback and volume
elements
Buttons: Play, Stop, Rewind, Forward and Mute
Slider: Volume
1
Access visual /
Auditory impairment
Playback, help, volume
and caption elements
Buttons: Play, Stop, Rewind, Forward, Mute and Caption
Select menu: Font, Color, Size and LanguageCaption
Navigator: Find and Help
Slider: Volume
2
Access Auditory /
Visual impairment
Playback, help, volume
and audio description
elements
Buttons: Play, Stop, Rewind, Forward, Mute and
AudioDescription
Select menu: LanguageAudio
Navigator: Help
Slider: Volume
3
Access visual and
auditory/ user
interface with all the
elements
Playback, help, volume,
caption* and audio
description** elements
Buttons: Play, Stop, Rewind, Forward, Mute, Caption* and
AudioDescription**
Select menu: Font*, Color*, Size*, LanguageCaption* and
LanguageAudio**
Navigator: Find* and Help
Slider: Volume
4/5
31

Authoring tool support (I)
32
In order to facilitate the design of a user agent which
delivers video content to experts and no experts in the field
of modeling or even accessibility and integrate adaptation
rules => Model-based Graphical Editor
Previous
knowledge
Specific
technology
UAAG 2.0
ISO 9241-171
Requirements
Related
Work

Authoring tool support (II)
33
• Review: Standards (previous and ATAG 2.0) and accessible
software technology (Java)
• Requirements: Functional and non-functional
Editor
Design
view
Palette
Development
view
Media
player
Contextual
help
Menu

Lab Demo
Authoring tool support (III)
34(González-García et al, 2015) ASSETS 2015

Validation:
Points to validate
H1
• Accessibility Requirements are sustained at
abstraction levels of Cameleon Reference
Framework
H2
• The design solution based on models allows
accomplishing the media player design
H3
• The model-based graphical editor allows the
generation of an accessible media player
TO EVALUATE
CONTRIBUTION 2
TO EVALUATE
CONTRIBUTION 1
TO EVALUATE
CONTRIBUTION 3

Validation:
How to validate (I)
H1
• Check if accessibility requirements and their semantic will
be satisfied according to design primitives and relationships
at each of the abstraction levels of Cameleon Reference
Framework
Native Additional
Play/Pause,
Stop, Resize,
Mute and
Volume
Rewind, Forward, Caption,
AudioDescription, Size, Font,
Color, LanguageCaption,
LanguageAudio, Help and
Find

Validation:
How to validate (II)
H2
• Lab demos will be accomplished using this proposal and its
integration in the research project
Cameleon
UsiXML
Task Model
AUI Model
CUI Model
Model driven
graphical
editor
FUI Model
MARIA
Task Model
AUI Model
Adaptation
rules
Model-based
graphical editor
FUI Model

Validation:
How to validate (III)
H3
• An exploratory study oriented to prove that the model-
based graphical editor can be used by every professional
independently of her/his knowledge about accessibility or
modeling
Exploratory
study
Participants 14
Stimuli Model-based graphical editor
Procedure Information
Task accomplishment
Survey
User experience
Task accomplishment
Personal data

Validation:
Results (I)
H1
• Transform accessibility requirements through the different
models of Cameleon
• The positive results of the user agent accessibility
assessment obtained when the graphical editor is used

Validation:
Results (II)
H2
• The models provided fulfil their objectives.
• The two lab demos accomplished using the graphical editor
of each approach
• The integration of this proposal in a research project
UsiXML MARIA

Validation:
Results (III)
H3
• Qualitative data obtained from the justifications of the
closed questions
• Quantitative data obtained from the user experience and
the accomplishment of the tasks
(100%) Task accomplishment responding to the necessities
(~28%) Use of profiles
(100%) Easy to use
(~7%) Use of contextual help
(100%) Recommend the use of the graphical editor
(100%) Technical participant agreed on the editor’s usefulness
Time of accomplishing tasks
Qualities: technical or human; complex or simple; impractical
or practical; tricky or direct; umpredictable or predictable;
confusing or clear; dificult to control or manageable

Validation:
Results (IV)
H3
• Qualitative data obtained from the justifications of the
closed questions
• Quantitative data obtained from the user experience and
the accomplishment of the tasks
4,286
6,357 6,214 6,357 6,071
6,643 6,714
0
1
2
3
4
5
6
7
8
Mark
Quality
Lowest mark
Highest mark
Average
Average time of accomplishment of the tasks Results of the user experience questionnaire
0
0,5
1
1,5
2
2,5
Task2
Task3
Task4
2,36
1,71
1,57
Time(minutes)
Average time (minutes) / task

• Due to the great amount of multimedia content delivered
on the Web, it is crucial that the content and software
which provides it have to be accessible
• Objectives which are being tackled:
 Perform a literature review
 Create methodological design approach
• Contributions which are being obtained:
 Accessibility requirements
 Workspace: Model-based Design approaches oriented to
experts in modeling
 A graphical editor oriented to designers who are not
experts in modeling neither in accessibility
Conclusions

• Integrate a UCD approach
• Incorporate different platforms with new interaction
modalities
• Spread the scope of the graphical editor
• Update this proposal according to the evolution of
accessibility standards
• Provide an extension of the Doctoral Thesis proposal with
an adaptive approach
• Incorporate new accessibility requirements
Future work

• This work has been influenced and has been partially
supported by
 The Regional Government of Madrid under the Research
Network MA2VICMR [S2009/TIC-1542]
 The Spanish Ministry of Education under the project
MULTIMEDICA [TIN2010-20644-C03-01]
 The European Commission Seventh Framework
Programme under TrendMiner project [FP7- ICT287863]
 The Spanish Ministry of Economy and Competitiveness
under eGovernAbility project [TIN2014-52665-C2-2-R]
Research and Development
projects

• Moreno, L., González-García, M., Martínez, P., and Iglesias, A. 2011. A
study of accessibility requirements for media players on the Web. 14th
International Conference on Human-Computer Interaction (HCII 2011),
Orlando, Florida, USA, July, 2011, LNCS, 6765, pp. 249-257.
• Moreno, L., Martínez, P., Iglesias, A., and González-García, M. 2011,
HTML5 support for an accessible user-video-interaction on the Web,
INTERACT 2011. Lisboa, Portugal, September, 2011, LNCS, Springer,
6949/2011, pp. 535-539.
• González-García, M., Moreno, L., Martínez, P., and Iglesias, A. 2011.
Requisitos de accesibilidad web en los reproductores multimedia,
Interacción 2011. Lisboa, Portugal, September, 2011, pp. 43-53.
• González-García, M., Moreno, L., Martínez, P., and Iglesias, A. 2011. Web
accessibility requirements for media players, INTERACT 2011. Lisboa,
Portugal, September, 2011, LNCS, 6949, pp. 669-674.
Results’ dissemination:
Accessibility requirements
46

• González-García, M., Miñon, R., Moreno, L., Martínez, P., and Abascal, J.
2013. A model-based graphical editor to design accessible media players.
Journal of Universal Computer Science, Volume19, Nº 18, pp. 2656-2676.
• González-García, M., Moreno, L., and Martínez, P. 2015. Approach design
of an accessible media player. Universal Access in the Information Society,
Springer, Volume 14, Number 1, pp. 45-55. DOI: 10.1007/s10209-013-0342-
z.
• González-García, M., Moreno, L., and Martínez, P. 2015. A Model-Based
Tool to develop an Accessible Media Player. ASSETS '15, Lisboa, Portugal,
October, 2015.
• González-García, M., Moreno, L., and Martínez, P. 2014. Adaptation rules
for Accessible Media Player Interface. Interacción 2014, Puerto de la Cruz,
Tenerife, Spain, September, 2014, Article Nº 5.
Methodological design approach (I)
47

• González-García, M., Moreno, L., and Martínez, P. 2014. Integration of
Accessibility Requirements in the Design of Multimedia User Agents
Interface. The first ACM womENcourage Conference, Manchester, United
Kingdom, January, 2014.
• González-García, M., Moreno, L., and Martínez, P. 2012. An approach to
User Interface Design of an accessible user agent. DSAI 2012, Douro
Region, Portugal, July, Elsevier, 14, pp. 254-262.
Methodological design approach (II)

References (I)
[1] WCAG 2.0. 2008. Web Content Accessibility Guidelines 2.0. http://www.w3.org/TR/WCAG20/.
[2] WAI. 2010. Web Accessibility Initiative. http://www.w3.org/WAI/.
[3] ISO. 2012. International Organization for Standardization, ISO 40500:2012, Information technology -- W3C Web Content Accessibility Guidelines (WCAG)
2.0). http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=58625.
[4] W3C. 2013. User Agent Accessibility Guidelines 2.0. http://www.w3.org/TR/UAAG20/.
[5] ISO. 2008. International Organization for Standardization, ISO 9241-171:2008, Ergonomics of human-system interaction (Guidance on software
accessibility). http://www.iso.org/iso/catalogue_detail.htm?csnumber=39080.
[6] CVAA. 2010. Federal Communications Commission, Twenty-First Century Communications and Video Accessibility Act. http://www.fcc.gov/guides/21st-
century-communications-and-video-accessibility-act-2010.
[7] ETSI. 2014. EN 301 549 V11.1, Accessibility requirements suitable for public procurement of ICT products and services in Europe.
http://www.etsi.org/deliver/etsi_en/301500_301599/301549/01.01.01_60/en_301549v010101p.pdf.
[8] W3C. 2015. Guidance on Applying WCAG 2.0 to Non-Web Information and Communications Technologies (WCAG2ICT). http://www.w3.org/TR/wcag2ict/.
[9] W3C, HTML5. 2014. A vocabulary and associated APIs for HTML and XHTML. http://www.w3.org/TR/html5/.
[10] Moreno, L., González-García, M., Martínez, P., and Iglesias, A. 2011. A study of accessibility requirements for media players on the Web. 14th
International Conference on Human-Computer Interaction (HCII 2011), Orlando, Florida, USA, July, 2011, Springer Computer Science Editorial, Volume: LNCS
6765, pp. 249-257.
[11] Schlungbaum, E. 1996. Model-based User Interface Software Tools. Current state of declarative models. GVU Technical Report; GIT-GVU-96-30. Georgia
Institute of Technology. http://hdl.handle.net/1853/3516.
[12] Truyen, F. 2006. WhitePaper: The Fast Guide to Model Driven Architecture. The Basics of Model Driven Architecture.
http://www.omg.org/mda/mda_files/Cephas_MDA_Fast_Guide.pdf.
[13] Kardoš, M. and Drozdová, M. 2010. Analytical Method of CIM to PIM Transformation in Model Driven Architecture (MDA). Journal of Information &
Organizational Sciences, Volume 34, Issue 1, Pages: 89-99.
[14] Bodart, F.,Hennebert, A.M., Leheureux, J.M., Sacre, I., and Vanderdonckt, J. 1993. Architecture Elements for Highly-Interactive Business-Oriented
Applications. In Lecture Notes in Computer Science, Vol. 153, L. Bass, J. Gornostaev & C. Unger (éds.), Springer-Verlag, Berlin, pp. 83-104.
[15] Nunes, N., and Cunha, J. 2000. Wisdom: a UML based Architecture for Interactive Systems. In Interactive Systems: Design, Specification, and Verification.
7th International Workshop DSV-IS, Limerick, Ireland, June, 2000. Ph. Palanque and F. Paternò (Eds.). LNCS Vol. 1946, Springer.
[16] Lozano, M.D., Montero, F., and González, P. 2004. Usability and Accessibility Oriented Development Process. Actas de la I Jornada sobre Metodologías
de Desarrollo de Interfaces de Usuario Dinámicas.
[17] Calvary, G., Coutaz, J., Bouillon, L., Florins, M., Limbourg, Q., Marucci, L., Paternò, F., Santoro, C., Souchon, N., Thevenin, D. and Vanderdonckt, J. 2002.
The CAMELEON Reference Framework, deliverable 1.1. http://giove.isti.cnr.it/projects/cameleon/pdf/CAMELEON%20D1.1RefFramework.pdf.
[18] W3C. 2014. Introduction to Model-Based User Interfaces. http://www.w3.org/TR/mbui-intro/
[19] UIDL. User Interface Description Languages, http://www.uidl.net.
[20] USIXML. 2003.USer Interface eXtensible Mark-up Language, http://www.usixml.eu/.
[21] MarcAbrams, M. and Phanouriou, C. 1999. UIML: An XML Language for Building Device-Independent User Interfaces. In Proceedings of XML’99,
Philadelphia. December 1999.
[22] Puerta, A. and Eisenstein, J. 2002. XIML: a common representation for interaction data. In Proceedings of the 7th international conference on Intelligent
user interfaces (IUI '02). Pages: 214-215.
[23] MARIA. 2013. Model-based language for interactive applications. http://giove.isti.cnr.it/tools/MARIA/home.
49

References (II)
[24] W3C. 2012. ConcurTaskTrees. http://www.w3.org/2012/02/ctt/
[25] Montero, F., and Lopez, V.M. 2007. Computer-Aided Design of User Interfaces V, Springer, Holanda, pp. 245-252.
[26] Eclipse. 2001. www.eclipse.org
[27] CTTE. 2013. ConcurTaskTrees Environment. http://giove.isti.cnr.it/tools/CTTE/home.
[28] MARIAE. 2013. Model-based language for interactive applications environment. http://giove.isti.cnr.it/tools/MARIAE/home.
50

‘‘Integration of Accessibility Requirements in
the Design of Multimedia User Agents
Interfaces’’
María González
PhD Program in Computer Science and Technology
Universidad Carlos III de Madrid, Spain
mgonza1@inf.uc3m.es
51

Integration of Accessibility Requirements in the Design of Multimedia User Agents Interfaces

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