The DIAGRAM Description feature defines a markup model for the creation of accessible content descriptions. The feature encapsulates a set of informative descriptions that can be referenced by images, graphics and other describable structures in any host grammar (e.g., HTML and EPUB).
The Description feature is intended to function both as a standalone model for descriptions (i.e., allowing descriptions to be authored and consumed on their own), to allow descriptions to be collected into a single document for distribution and to be directly integrated into host languages.
The contents of this data model were developed under a grant from the US Department of Education, #H327B100001, under the direction of the DIAGRAM Center. However, those contents do not necessarily represent the policy of the US Department of Education, and you should not assume endorsement by the Federal Government. Project Officer, Glinda Hill.
The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this section are to be interpreted as described in RFC2119.
The namespace of all attribute components defined by this feature is:
http://www.daisy.org/ns/z3998/authoring/features/description/
This resource directory represents version
1.0 of the DIAGRAM Description feature:
This release may not be the most recently published (current) version of the DIAGRAM Description feature. The current version should always be obtained from the static URI: http://www.daisy.org/z3998/2012/auth/features/description/current/
This feature must be identified as
description in Z39.98-AI document feature declarations.
The canonical identity URI is:
http://www.daisy.org/z3998/2012/auth/features/description/1.0/
This version of the feature is compliant with the Z39.98-2012 Specification.
The normative
RelaxNG schema for version
1.0 of the DIAGRAM Description feature is
z3998-feature-description.rng.
Note - this feature schema does not represent an entire document model; it is intended for inclusion in host profiles.
This feature makes the following components available for inclusion in host profiles:
description element.
This section defines processing agent behaviors that extend the default behaviors defined in Processing agent conformance definition.
If the processing agent supports this feature and the client has activated processing of components defined by this feature, then the processing agent must process all encountered components defined by this feature in accordance with the semantics defined in the definitions below.
If the processing agent
supports this feature and the client has
deactivated processing of components defined by this feature, then the processing agent must employ the
Ignore or
Discard behaviors as defined below. The
Ignore behavior is the default; the
Discard behavior must only be employed when client has explicitly instructed the processing agent to do so.
If a processing agent recognizes but does not support this feature, it must employ one of the following behaviors:
Upon encountering a document instance with this feature enabled, the processing agent issues a notification, and then aborts the processing.
While traversing the document tree and encountering an element in the feature namespace, the processing agent ignores the element, and continues the traversal.
While traversing the document tree and encountering an element in the feature namespace, the processing agent discards the element, and continues the traversal.
The
abort behavior is the default; the
ignore and
discard behaviors must only be employed when the processing agent is explicitly instructed to do so by the client.
Processing agents that employ the
ignore or
discard behaviors should issue a notification.
If a processing agent does not recognize this feature, it must, as dictated in Processing agent conformance definition, abort processing and issue an error message.
The component definitions provided below follow the conventions used in Core Modules.
The DIAGRAM
Description feature supports traditional long descriptions and also includes markup for including summaries and simplified language descriptions. It also allows the embedding of simplified image versions of the source and also tactile printing-ready equivalents.
The age and/or education level of the intended audience can be set in the description metadata.
This feature makes available a single public element: the
description
element. Other components defined in this feature are intended for use augmenting this element.
This feature inherits elements, attributes and additional features from the Z39.98-2012 Core Modules.
| Name | Default attribute model | Default content model | Default usage context |
|---|---|---|---|
description
|
xml:id?,
xml:base?
|
d:head?,
d:body
|
Block.class
|
head
|
Document.attrib
|
meta+
|
d:description
|
body
|
Document.attrib
|
(
d:summary? &
d:longdesc &
d:simplifiedLanguageDescription* &
d:tactile* &
d:simplifiedImage* &
annotation*)
|
d:description
|
summary
|
Block.attrib
|
(text | z3998.Text.class | z3998.Phrase.class)+
|
d:body
|
longdesc
|
Block.attrib
|
(z3998.Block.class)+ | (text | z3998.Text.class | z3998.Phrase.class)+
|
d:body
|
simplifiedLanguageDescription
|
Block.attrib
|
(z3998.Block.class)+ | (text | z3998.Text.class | z3998.Phrase.class)+
|
d:body
|
about
|
Block.attrib
|
(text | z3998.Text.class | z3998.Phrase.class)+
|
d:simplifiedLanguageDescription,
d:tactile,
d:simplifiedImage
|
tactile
|
Block.attrib
|
(z3998.object.block+, z3998.feature.description.tour?)
|
d:body
|
braille
|
Block.attrib
|
(text | *)
|
d:tactile
|
tour
|
Block.attrib
|
(z3998.Block.class)+ | (text | z3998.Text.class | z3998.Phrase.class)+
|
d:tactile
,
d:simplifiedImage
|
simplifiedImage
|
Block.attrib
|
(z3998.object.block+, z3998.feature.description.tour?)
|
d:body
|
| Name | Default values | Default usage context |
|---|---|---|
brlFormat
|
NMTOKENS
|
d:braille
|
The
description element is the root container element for a description. It consists of an optional container element for metadata information (the
head
) and a required container for the different description types and alternate image renditions (the
body
).
The language of the description can be specified by attaching an
xml:lang
attribute to the
description element. If the description will be made available in a standalone context (i.e., in which its language cannot be inherited from a host content document), the language should always be specified.
The
DIAGRAM Description profile provides the ability to compile one or more
description elements into a single document for distribution (e.g., to accompany an EPUB).
When storing a description in a standalone context, the Description feature namespace
http://www.daisy.org/ns/z3998/authoring/features/description/ should be declared on the
description element using the xmlns namespace association mechanism defined in
XMLNAMES
. Although not required, the prefix
d is recommended.
| Local name |
description
|
|---|---|
| Namespace |
http://www.daisy.org/ns/z3998/authoring/features/description/
|
| Default usage context |
Block.class
|
| Default attribute model |
xml:id?,
xml:base?
|
| Content model |
d:head?,
d:body
|
| Content model alterability | This content model is fixed, and must not be altered when activating this module. |
| Optionality | This element must not be omitted when activating this module. |
head element
The description
head element contains meta information about the enclosing
description
element.
The meta information in the description
head element should not be treated as document content, but may be used for display and other purposes when rendering descriptions.
Although all metadata is optional, descriptions should, at a minimum, include an identifier, the intended reader age and/or school grade level. See the DIAGRAM Descriptions Vocabulary for a set of predefined RDF properties. Properties from other RDF vocabularies can also be included, provided their prefix is declared.
If age and grade-level metadata is omitted, the containing
description should be assumed to be applicable to all readers.
| Local name |
head
|
|---|---|
| Namespace |
http://www.daisy.org/ns/z3998/authoring/features/description/
|
| Default usage context |
d:description
|
| Default attribute model |
Document.attrib
|
| Default content model |
meta+
|
| Optionality | This element may be omitted when activating this module. |
body element
The description
body element contains the accessible description forms that readers can select from depending on their needs.
The description
body must minimally contain the primary description of the associated content in a child
longdesc
element.
The description body may also optionally compliment the primary description with a briefer summary and a simplified language representation.
The
body of the description can also be used to carry alternative images for readers unable to adequately interact with the source image. The
tactile
element can be used to include a tactile image and accompanying
tour, and the
simplifiedImage
element can be used to include images more accessible to various reader needs.
| Local name |
body
|
|---|---|
| Namespace |
http://www.daisy.org/ns/z3998/authoring/features/description/
|
| Default usage context |
d:description
|
| Default attribute model |
Document.attrib
|
| Default content model |
(
d:summary? &
d:longdesc &
d:simplifiedLanguageDescription* &
d:tactile* &
d:simplifiedImage* &
annotation*)
|
| Optionality | This element may be omitted when activating this module. |
summary element
The
summary element contains a shorter, more succinct version of the primary description in the
longdesc
element.
| Local name |
summary
|
|---|---|
| Namespace |
http://www.daisy.org/ns/z3998/authoring/features/description/
|
| Default usage context |
d:body
|
| Default attribute model |
Block.attrib
|
| Default content model |
(text | z3998.Text.class | z3998.Phrase.class)+
|
| Optionality | This element may be omitted when activating this module. |
The following model restrictions apply to this element:
The
summary element must neither be empty nor contain only whitespace.
longdesc element
The
longdesc element contains the primary description of the associated image, graphic or visually-oriented structure.
The
longdesc should contain a comprehensive explanation of the referenced item. See the
summary
element for information on how to include a compact description.
| Local name |
longdesc
|
|---|---|
| Namespace |
http://www.daisy.org/ns/z3998/authoring/features/description/
|
| Default usage context |
d:body
|
| Default attribute model |
Block.attrib
|
| Default content model |
(z3998.Block.class)+ | (text | z3998.Text.class | z3998.Phrase.class)+
|
| Optionality | This element may be omitted when activating this module. |
The following model restrictions apply to this element:
The
longdesc element must neither be empty nor contain only whitespace.
simplifiedLanguageDescription element
The
simplifiedLanguageDescription element contains a simplified language version of the primary description in the
longdesc
element.
| Local name |
simplifiedLanguageDescription
|
|---|---|
| Namespace |
http://www.daisy.org/ns/z3998/authoring/features/description/
|
| Default usage context |
d:body
|
| Default attribute model |
Block.attrib
|
| Default content model |
(z3998.Block.class)+ | (text | z3998.Text.class | z3998.Phrase.class)+
|
| Optionality | This element may be omitted when activating this module. |
The following model restrictions apply to this element:
The
simplifiedLanguageDescription element must neither be empty nor contain only whitespace.
about element
The
about element provides a brief, human-readable explanation of the nature of its parent (e.g., the file format, resolution, audience, etc.).
The element is intended to provide a label for end users of the content -- for example, to explain the format of the content to facilitate content selection.
| Local name |
about
|
|---|---|
| Namespace |
http://www.daisy.org/ns/z3998/authoring/features/description/
|
| Default usage context |
d:simplifiedLanguageDescription,
d:tactile,
d:simplifiedImage
|
| Default attribute model |
Block.attrib
|
| Default content model |
(text | z3998.Text.class | z3998.Phrase.class)+
|
| Optionality | This element may be omitted when activating this module. |
The following model restrictions apply to this element:
The
about element must neither be empty nor contain only whitespace.
tactile element
The
tactile element contains an alternative tactile image. The element may contain one or more identical images for different production methods (e.g., one for swell paper production and another for stereolithograph printing).
The tactile image may also include an explanatory
tour
.
This specification does not place any restrictions on the format used to represent the tactile image, but images should be final-form representations for output rendering by end users. The
role
attribute should be used to differentiate the production use for each image.
| Local name |
tactile
|
|---|---|
| Namespace |
http://www.daisy.org/ns/z3998/authoring/features/description/
|
| Default usage context |
d:body
|
| Default attribute model |
Block.attrib
|
| Default content model |
(z3998.object.block+, z3998.feature.description.tour?)
|
| Optionality | This element may be omitted when activating this module. |
braille element
The
braille element contains an alternative braille representation. It may contain preformatted braille text, or embed a format such as PEF.
| Local name |
braille
|
|---|---|
| Namespace |
http://www.daisy.org/ns/z3998/authoring/features/description/
|
| Default usage context |
d:tactile
|
| Default attribute model |
Block.attrib
|
| Default content model |
(text | *)
|
| Optionality | This element may be omitted when activating this module. |
The following model restrictions apply to this element:
The
braille element must neither be empty nor contain only whitespace.
tour element
The
tour element is associated with a tactile graphic or a simplified alternative image, and provides orientation. In addition, the tour can explain how to explore the tactile or simplified image.
| Local name |
tour
|
|---|---|
| Namespace |
http://www.daisy.org/ns/z3998/authoring/features/description/
|
| Default usage context |
d:tactile
,
d:simplifiedImage
|
| Default attribute model |
Block.attrib
|
| Default content model |
(z3998.Block.class)+ | (text | z3998.Text.class | z3998.Phrase.class)+
|
| Optionality | This element may be omitted when activating this module. |
simplifiedImage element
The
simplifiedImage element contains a simplified version of the source image. The element may contain one or more identical images in different formats.
The simplified image may also include an explanatory
tour
.
| Local name |
simplifiedImage
|
|---|---|
| Namespace |
http://www.daisy.org/ns/z3998/authoring/features/description/
|
| Default usage context |
d:body
|
| Default attribute model |
Block.attrib
|
| Default content model |
(z3998.object.block+, z3998.feature.description.tour?)
|
| Optionality | This element may be omitted when activating this module. |
brlFormat attribute
The
brlFormat attribute expresses processing information for a
d:braille
element.
The attribute takes as its value one or more tokens.
| Local name |
brlFormat
|
|---|---|
| Namespace | None |
| Default usage context |
d:braille
|
| Default value(s) |
NMTOKENS
|
| Optionality | This attribute must not be omitted when activating this module. |
| Schema | Language |
|---|---|
| z3998-feature-description.rng | RelaxNG |
Activation of this module depends on the global-classes and Core modules also being activated.
The following informative schemata are available:
Refer to the Z39.98-AI community portal for information on available software tools.
A minimally complete example of a description is available.
The below list represents the modules at the time of version 1.0 of this feature.
The occurrence of the keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in documentation fields embedded in these modules are to be interpreted as described in RFC2119.