ISO/IEC TS 20071-21:2015

TECHNICAL ISO/IEC TS
SPECIFICATION 20071-21
First edition
2015-12-15
Information technology — User
interface component accessibility —
Part 21:
Guidance on audio descriptions
Technologies de l’information — Accessibilité du composant interface
utilisateur —
Partie 21: Directives sur les descriptions audio
Reference number
©
ISO/IEC 2015
© ISO/IEC 2015, Published in Switzerland
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ii © ISO/IEC 2015 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Terms and definitions . 1
2.1 General terms . 2
2.2 Audio-specific terms . 2
2.3 Language of presentation terms . 3
2.4 Audio description production terms . 4
3 Framework and process considerations for audio description . 5
3.1 General . 5
3.1.1 Alternate names for audio description . 5
3.1.2 Motivation for audio description and spoken subtitles . 5
3.2 Types of audio description . 5
3.2.1 Live audio description . 5
3.2.2 Pre-mixed audio description . 5
3.2.3 Harmonious commentary . 6
3.2.4 Extended audio description . 6
3.3 Creating audio description . 6
3.3.1 Narrator preparation . 6
3.3.2 Content genre and programme category . 7
3.3.3 Scripting . 7
3.3.4 Writer considerations. 7
3.3.5 Recording . 7
3.3.6 Volume . 7
3.3.7 Audio technician considerations . 8
3.3.8 Inclusion of consumers in the process of creating audio description . 8
3.3.9 Inclusion of consumers in evaluating audio description . 8
3.4 Live audio description . 8
3.4.1 Live narration considerations . 8
3.4.2 Preparing for live narration. 9
3.4.3 Narrator transitions in live audio . 9
3.5 Pre-recorded descriptions .10
3.5.1 Creation of pre-mixed audio after main production process .10
3.5.2 Audio description team for pre-mixed audio .10
3.5.3 Evaluation of pre-mixed audio .10
3.5.4 Voices for pre-mixed audio .10
3.5.5 Sound engineering for pre-mixed audio .10
4 Guidance on audio description .10
4.1 General considerations .10
4.1.1 User considerations.10
4.1.2 Consistency across technologies .11
4.1.3 Consistency within a programme and series .11
4.1.4 Placement of descriptions .11
4.1.5 Use of pauses .11
4.2 Developing audio description .11
4.2.1 Clarity in audio description .11
4.2.2 Creativity in audio description .12
4.2.3 Narrating/reading audio description script .12
4.3 Styles of narration .13
4.3.1 Newsreader style .13
4.3.2 Commentator style .13
4.3.3 First person .13
4.3.4 Third person .14
© ISO/IEC 2015 – All rights reserved iii

4.4 Levels of importance .14
4.4.1 Using importance levels .14
4.4.2 Essential information.14
4.4.3 Significant information . .14
4.4.4 Helpful information .15
4.4.5 Irrelevant information .15
4.5 General guidance on descriptions .16
4.5.1 Description of sounds .16
4.5.2 Logos/credits/titles .16
4.5.3 On-screen text .16
4.6 Guidance on identifying objects .16
4.6.1 Identifying objects .16
4.6.2 Describing colour .17
4.6.3 Describing visual effects .17
4.7 Guidance on identifying persons .17
4.7.1 Identifying characters or places by name .17
4.7.2 Physical appearance.18
4.7.3 Race/ethnic origin .19
4.7.4 Gender-related .20
4.7.5 Disabilities .20
4.7.6 Age . .21
4.8 Guidance on relationships . .22
4.8.1 General guidance on explicit content .22
4.8.2 General guidance on relationships .22
4.8.3 Establishing place/setting/time of day .22
4.8.4 Interaction between animated characters/objects and real actors .23
4.9 Guidance on parts of speech .23
4.9.1 Descriptive verbs .23
Bibliography .24
iv © ISO/IEC 2015 – All rights reserved

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical
activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the
work. In the field of information technology, ISO and IEC have established a joint technical committee,
ISO/IEC JTC 1.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for
the different types of document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical
Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/IEC JTC 1, Information technology, SC 35, User
interfaces.
ISO/IEC 20071 consists of the following parts, under the general title Information technology — User
interface component accessibility:
— Part 11: Guidance for alternative text for images [Technical Specification]
— Part 21: Guidance on audio description [Technical Specification]
© ISO/IEC 2015 – All rights reserved v

Introduction
This part of ISO/IEC 20071 provides audio description developers and practitioners with guidance in
creating effective content describing audiovisual material in an auditory-only modality, the style or
manner in which audio description is delivered, the audio description script and script time cues, in
relation to the original content. The circumstances to which audio description applies include recorded
video, broadcast and broadband television, cinema, live or recorded drama, museum and art gallery
exhibits, heritage tours, news, and comedies. Some of this content is static and unchanging, some is
dynamic, some is expressed in a visual modality alone, and some in a combination of visual and
auditory modalities.
An example of mainstream use of audio description techniques can be found in sports commentary.
It can be enjoyed by diverse audiences and uses personalities, emotional expression, and reaction to
content to express qualities of the original content.
Audiovisual material is produced for people who can see and hear. It is also typically produced in a
specific language for a particular audience. Translations of the original auditory content and associated
audio description can be provided in different languages. Providing audio description and translating
into other languages can be beneficial to diverse users in diverse contexts, including persons who are
blind or persons with low vision, persons with learning difficulties or cognitive impairments and, in the
case of translation, persons who need the content to be in another language. Translating subtitles and
other on-screen text and providing those in auditory form can also be beneficial.
Producing audio description can be thought of in a similar way to language translation in that it involves
several kinds of subjective decisions, for example, the use of vocabulary, tone, speed, intonation, and
expression. The accuracy and quality that audio describers or script writers can achieve is determined
by matching the factors above with the requirements of the original content.
The creation and delivery of audio description based on the guidance in this part of ISO/IEC 20071 is
not intended to interfere with or change the meaning of the original content, or the freedom of speech,
expression, or opinion of rights holders.
A further benefit of providing audio description can be the raising of awareness of barriers experienced
by blind persons and persons with low vision and other beneficiaries in accessing audiovisual content.
The use of this part of ISO/IEC 20071 can also help embed universal and inclusive designed media
content production practices in educational programmes (such as film, theatre performances, museum
and art gallery exhibits, and other media).
vi © ISO/IEC 2015 – All rights reserved

TECHNICAL SPECIFICATION ISO/IEC TS 20071-21:2015(E)
Information technology — User interface component
accessibility —
Part 21:
Guidance on audio descriptions
1 Scope
This part of ISO/IEC 20071 provides recommendations for describing audiovisual content in an auditory
modality for use in recorded video presentations, broadcast television, cinema, live or recorded drama,
museum and art gallery exhibits, heritage tours, news, and comedies, regardless of the language and
technology being used to transmit and present the recorded or live audiovisual content.
NOTE 1 There are many secondary users of audio description, but the primary and intended users of audio
description are blind persons or persons with low vision and their friends and family.
This part of ISO/IEC 20071 provides guidance on the subjective nature of creating audio description.
It also provides guidance for audio description developers (script writers, voice narrators, and
organizations or groups responsible for delivering audio description) in faithfully and accurately
representing audiovisual content.
NOTE 2 It might not always be possible to provide an equivalent experience due to limitations in the amount
of time available for audio description depending on the content being described.
This part of ISO/IEC 20071 applies to describing audiovisual content and does not consider the devices
or transmission mechanisms used to deliver the content or the audio description. These devices include,
but are not limited to, televisions, computers, wireless devices, projection equipment, DVD and home
cinema equipment and other forms of user interface technology. Therefore, this part of ISO/IEC 20071
does not consider transcoding files for the various video outputs.
NOTE 3 Technical matters of transmission and distribution are covered by other International Standards (e.g.
MPEG standards and other technical international standards such as IEC 62731).
This part of ISO/IEC 20071 provides guidance on how to approach user preferences, available styles
and flexibility in approaches to audio description.
It does not apply to static images contained in electronic documents (see ISO/IEC 20071−11 for guidance
on text alternatives for images).
It applies to auditory presentations intended to be transmitted or delivered simultaneously to the
original audiovisual content.
NOTE 4 Limitations experienced by broadcasters or people in synchronous environments might be reduced
online or in asynchronous environments.
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
© ISO/IEC 2015 – All rights reserved 1

2.1 General terms
2.1.1
audiovisual content