This section is informative.
Since the publication of SMIL 1.0 [SMIL10], interest in the integration of SMIL concepts with the HTML, the HyperText Markup Language [HTML4], and other XML languages, has grown. Likewise, the W3C HTML Working Group has specified XHTML, the Extensible HyperText Markup Language [XHTML10], in preparation to subset, extend, and integrate it with other languages. The strategy considered for integrating respective functionality with other XML-based languages is based on the concepts of modularization and profiling [SMIL-MOD], [XMOD].
Modularization is an approach in which markup functionality is specified as a set of modules that contain semantically-related XML elements, attributes, and attribute values. Profiling is the creation of an XML-based language through combining these modules, in order to provide the functionality required by a particular application.
Profiling introduces the ability to tailor an XML-based language to specific needs, e.g. to optimize presentation and interaction for the client's capabilities. Profiling also adds the ability for integrating functionality from other markup languages, releasing the language designer from specifying that functionality. Moreover, it provides for consistency in markup through the use of the same model to incorporate a function. Identical constructs ease authoring, while at the user agent side there is a potential for re-use of code. For example, a scheduler supporting SMIL timing and synchronization functionality could be used for SMIL documents, XHTML+SMIL documents, and SVG documents.
Modularization enables language designers to specify dedicated markup intended for integration with other, existing, language profiles. Examples of specifications intended for such integration are MathML and XForms [MathML], [XFORMS].
Modularization and profiling use the extensibility properties of XML, and related technology like XML namespaces and XML Schema [XML10], [XML-NS], [XSCHEMA].
This part of the SMIL 2.0 specification describes the framework on which SMIL modularization and profiling is based, and specifies the SMIL 2.0 Modules, their identifiers, and the requirements for conformance within this framework.
This section is informative.
The modularization approach used in this specification derives from that set forth in XHTML Modularization [XMOD]. The framework on which SMIL modularization and profiling is based, is informally described here.
A Module is a collection of semantically-related XML elements, attributes, and attribute values that represents a unit of functionality. Modules are defined in coherent sets. This coherency is expressed in that the elements of these modules are associated with the same namespace.
A Language Profile is a combination of modules. Modules are atomic, i.e. they cannot be subset when included in a language profile. Furthermore, a module specification may include a set of integration requirements, to which language profiles that include the module must comply.
Commonly, there is a main language profile that incorporates nearly all the modules associated with a single namespace. For example, the SMIL 2.0 language profile uses most of the SMIL 2.0 modules. Usually, the same name is used to loosely reference both - "SMIL 2.0" in the example. Also, the name "profile" is used to mean "language profile".
Other language profiles can be specified that are subsets of the larger one, or that incorporate a mixture of modules associated with different namespaces. SMIL 2.0 Basic is an example of the first, XHTML+SMIL of the latter.
A special module in a language profile is the so-called Structure Module, in that it contains the root element of the language profile, e.g. <smil> or <html>. Any language profile that incorporates modules associated with a single namespace will include the Structure module associated with that namespace.
Other modules that require special mention are those that characterize the core of the functionality provided by the namespace. This is expressed by the notions of host language and integration set. Both of them relate to a set of conformance requirements for language profiles, which includes the requirement to incorporate at least the core set of modules. The set may be different for a host language and an integration set. A host language must incorporate the Structure module; an integration set need not. There may be other differences as well.
The main purpose of language profile conformance is to enhance interoperability. Preferably, the mandatory modules for host language conformance are defined in such a way that any document interchanged in a conforming language profile will yield a reasonable presentation when the document renderer, while supporting the associated mandatory module set, would ignore all other (unknown) elements and attributes. Here, "reasonable presentation" is to be understood as something intelligible, which is not necessarily a close reflection of the author's original intentions. To achieve the latter, a negotiation would have to be conducted to agree on the specific language profile to be used for the document interchange.
This section is normative.
SMIL functionality is partitioned into ten functional areas. Within each functional area a further partitioning is applied into modules. All of these modules, and only these modules, are associated with the SMIL namespace.
The functional areas and their corresponding modules are:
This section is informative.
Each of these modules introduces a set of semantically-related elements, properties, and attributes. Each functional area has a corresponding section in this specification document. Further details on each of the modules is specified within those sections.
The modules may be independent or complementary. For example, the SyncMaster module requires and builds upon the SyncBehavior module, but the PrefetchControl and SkipContentControl modules are independent from each other. In addition, some modules require modules from other functional areas.
Modules specify their integration requirements. When one module requires another module for basic features and as a prerequisite for integration, a language profile must include the second module in order to include the first. The first module is said to be a dependent of the second module. Dependency may be nested, in that a module may be dependent on a module that is dependent itself.
Table 1 presents the SMIL 2.0 modules and the modules they dependent on.
| Module | Dependencies |
| AccessKeyTiming | NONE |
| AudioLayout | BasicLayout |
| BasicAnimation | BasicInlineTiming |
| BasicContentControl | NONE |
| BasicInlineTiming | NONE |
| BasicLayout | NONE |
| BasicLinking | NONE |
| BasicMedia | NONE |
| BasicTimeContainers | NONE |
| BasicTransitions | NONE |
| BrushMedia | NONE |
| CustomTestAttributes | BasicContentControl |
| EventTiming | NONE |
| ExclTimeContainers | NONE |
| FillDefault | BasicTimeContainers, and/or ExclTimeContainers, and/or TimeContainerAttributes |
| HierarchicalLayout | BasicLayout |
| InlineTransitions | NONE |
| LinkingAttributes | NONE |
| MediaAccessibility | MediaDescription |
| MediaClipMarkers | MediaClipping |
| MediaClipping | BasicMedia |
| MediaDescription | NONE |
| MediaMarkerTiming | NONE |
| MediaParam | BasicMedia |
| MetaInformation | NONE |
| MinMaxTiming | NONE |
| MultiArcTiming | AccessKeyTiming, and/or BasicInlineTiming, and/or EventTiming, and/or MediaMarkerTiming, and/or RepeatValueTiming, and/or SyncbaseTiming, and/or WallclockTiming |
| MultiWindowLayout | BasicLayout |
| ObjectLinking | BasicLinking |
| PrefetchControl | NONE |
| RepeatTiming | NONE |
| RepeatValueTiming | NONE |
| RestartDefault | RestartTiming |
| RestartTiming | NONE |
| SkipContentControl | NONE |
| SplineAnimation | BasicAnimation |
| Structure | BasicContentControl, and BasicInlineTiming, and BasicLayout, and BasicLinking, and BasicMedia, and BasicTimeContainers, and SkipContentControl, and SyncbaseTiming |
| SyncbaseTiming | NONE |
| SyncBehavior | BasicTimeContainers, and/or ExclTimeContainers, and/or TimeContainerAttributes |
| SyncBehaviorDefault | SyncBehavior |
| SyncMaster | SyncBehavior |
| TimeContainerAttributes | NONE |
| TimeManipulations | NONE |
| TransitionModifiers | BasicTransitions, and/or InlineTransitions |
| WallclockTiming | NONE |
This section is informative.
SMIL is an XML-based language and conforms to the (XML) DOM Core [DOM1], [DOM2]. In the future, a SMIL-specific DOM recommendation may specify support for timing and synchronization, media integration, and other synchronized multimedia functionality.
A language profile may include DOM support. The granularity of DOM being supported corresponds to the modules being selected in that language profile. As with all modules, required support for the DOM is an option of the language profile.
This section is informative.
This section specifies the identifiers for the SMIL 2.0 namespace and the SMIL 2.0 modules. Each SMIL host language conformant language profile is requested to explicitly state the namespace URI that is to be used to identify it. That namespace URI must comply with the "Requirements on Identifiers for SMIL Host Language Conformant Language Profiles", defined below.
This section is normative.
Documents authored in language profiles that include the SMIL Structure module
can be associated with the "application/smil" mime type. Documents using
the "application/smil" mime type are required to be host language
conformant.
This section is normative.
The XML namespace identifier for the complete set of SMIL 2.0 modules, and the elements and attributes that are contained within is:
http://www.w3.org/2001/SMIL20/
This section is normative.
Each module in this specification has a unique identifier associated with it. They are intended to uniquely and consistently identify each of them. They should be used as values in a test for whether an implementation includes a specific module, as well as in other circumstances where a need to refer to a specific SMIL 2.0 module is necessary.
Table 2 summarizes the identifiers for SMIL 2.0 modules.
| Module name | Identifier |
| AccessKeyTiming | http://www.w3.org/2001/SMIL20/AccessKeyTiming |
| AudioLayout | http://www.w3.org/2001/SMIL20/AudioLayout |
| BasicAnimation | http://www.w3.org/2001/SMIL20/BasicAnimation |
| BasicContentControl | http://www.w3.org/2001/SMIL20/BasicContentControl |
| BasicInlineTiming | http://www.w3.org/2001/SMIL20/BasicInlineTiming |
| BasicLayout | http://www.w3.org/2001/SMIL20/BasicLayout |
| BasicLinking | http://www.w3.org/2001/SMIL20/BasicLinking |
| BasicMedia | http://www.w3.org/2001/SMIL20/BasicMedia |
| BasicTimeContainers | http://www.w3.org/2001/SMIL20/BasicTimeContainers |
| BasicTransitions | http://www.w3.org/2001/SMIL20/BasicTransitions |
| BrushMedia | http://www.w3.org/2001/SMIL20/BrushMedia |
| CustomTestAttributes | http://www.w3.org/2001/SMIL20/CustomTestAttributes |
| EventTiming | http://www.w3.org/2001/SMIL20/EventTiming |
| ExclTimeContainers | http://www.w3.org/2001/SMIL20/ExclTimeContainers |
| FillDefault | http://www.w3.org/2001/SMIL20/FillDefault |
| HierarchicalLayout | http://www.w3.org/2001/SMIL20/HierarchicalLayout |
| InlineTransitions | http://www.w3.org/2001/SMIL20/InlineTransitions |
| LinkingAttributes | http://www.w3.org/2001/SMIL20/LinkingAttributes |
| MediaAccessibility | http://www.w3.org/2001/SMIL20/MediaAccessibility |
| MediaClipMarkers | http://www.w3.org/2001/SMIL20/MediaClipMarkers |
| MediaClipping | http://www.w3.org/2001/SMIL20/MediaClipping |
| MediaDescription | http://www.w3.org/2001/SMIL20/MediaDescription |
| MediaMarkerTiming | http://www.w3.org/2001/SMIL20/MediaMarkerTiming |
| MediaParam | http://www.w3.org/2001/SMIL20/MediaParam |
| Metainformation | http://www.w3.org/2001/SMIL20/Metainformation |
| MinMaxTiming | http://www.w3.org/2001/SMIL20/MinMaxTiming |
| MultiArcTiming | http://www.w3.org/2001/SMIL20/MultiArcTiming |
| MultiWindowLayout | http://www.w3.org/2001/SMIL20/MultiWindowLayout |
| ObjectLinking | http://www.w3.org/2001/SMIL20/ObjectLinking |
| PrefetchControl | http://www.w3.org/2001/SMIL20/PrefetchControl |
| RepeatTiming | http://www.w3.org/2001/SMIL20/RepeatTiming |
| RepeatValueTiming | http://www.w3.org/2001/SMIL20/RepeatValueTiming |
| RestartDefault | http://www.w3.org/2001/SMIL20/RestartDefault |
| RestartTiming | http://www.w3.org/2001/SMIL20/RestartTiming |
| SkipContentControl | http://www.w3.org/2001/SMIL20/SkipContentControl |
| SplineAnimation | http://www.w3.org/2001/SMIL20/SplineAnimation |
| Structure | http://www.w3.org/2001/SMIL20/Structure |
| SyncbaseTiming | http://www.w3.org/2001/SMIL20/SyncbaseTiming |
| SyncBehavior | http://www.w3.org/2001/SMIL20/SyncBehavior |
| SyncBehaviorDefault | http://www.w3.org/2001/SMIL20/SyncBehaviorDefault |
| SyncMaster | http://www.w3.org/2001/SMIL20/SyncMaster |
| TimeContainerAttributes | http://www.w3.org/2001/SMIL20/TimeContainerAttributes |
| TimeManipulations | http://www.w3.org/2001/SMIL20/TimeManipulations |
| TransitionModifiers | http://www.w3.org/2001/SMIL20/TransitionModifiers |
| WallclockTiming | http://www.w3.org/2001/SMIL20/WallclockTiming |
In addition to the module identifiers above, there may be different features and variances from one language profile to another that may not be expressed as the support or non-support of a particular module. These features may be expressed using the following identifiers:
http://www.w3.org/2001/SMIL20/NestedTimeContainers
http://www.w3.org/2001/SMIL20/DeprecatedFeatures
Implementations that support the SMIL BasicContentControl module must allow these as identifiers for use with the XML namespace mechanism, and must allow the associated namespace identifier to be used with the systemRequired test attribute. Profiles must identify those attributes for which an implementation must return "true" (this is an integration requirement). Implementations must return "false" for modules or features which are not fully supported.
Modules can also be identified collectively. The following four module collections are defined:
http://www.w3.org/2001/SMIL20/
http://www.w3.org/2001/SMIL20/Language
http://www.w3.org/2001/SMIL20/HostLanguage
http://www.w3.org/2001/SMIL20/IntegrationSet
This section is informative.
In this section we specify the rules for SMIL host language and SMIL integration set conformance. First, the conformance requirements for host language conformance and integration set conformance are given. The requirements are similar to those set forth for XHTML host language document type conformance and XHTML integration set document type conformance [XMOD]. In a final section the requirements on identifiers for host language conformant language profiles are given.
Currently, there exist three language profiles using SMIL 2.0 Modules. They are the SMIL 2.0 Language Profile, the SMIL 2.0 Basic Language Profile, and the XHTML+SMIL 2.0 Language Profile [XHTML+SMIL]. The first two are SMIL host language conformant, the third is SMIL integration set conformant.
This section is normative.
The following two tables list names used to collectively reference certain sets of SMIL 2.0 elements and attributes. These are used in the definitions of the minimum support in the two sections below on SMIL host language conformance and SMIL integration set conformance. The term "minimum support" is used to refer to the minimum set of elements that an element can contain, and the minimum set of attributes that can be used on an element.
| Element Set Name | Elements |
| TIMING-ELMS | par, seq |
| MEDIA-ELMS | ref, animation, audio, img, video, text, textstream |
| EMPTY | no elements are required as a minimum |
| Attribute Set Name | Attributes |
| TIMING-ATTRS | begin, end, dur, repeatDur, repeatCount, max, min, fill, endsync |
| CONTCTRL-ATTRS | systemBitrate, systemCaptions, systemLanguage, systemRequired, systemScreenSize, systemScreenDepth, systemOverdubOrSubtitle, systemAudioDesc, , systemCPU, systemComponent |
| MEDIA-ATTRS | src, type |
| LINKING-ATTRS | href, sourceLevel, destinationLevel, sourcePlaystate, destinationPlaystate, show, accesskey, tabindex, target, external, actuate, alt |
| COMMON-ATTRS | id, class, xml:lang, title |
This section is normative.
A language profile is said to be SMIL 2.0 host language conformant if it includes the following modules:
In addition, the following requirements must be satisfied:
| Element | Minimum Support | |
| Elements | Attributes | |
| smil | head, body | COMMON-ATTRS, CONTCTRL-ATTRS, xmlns |
| head | layout, switch | COMMON-ATTRS |
| body | TIMING-ELMS, MEDIA-ELMS, switch, a | COMMON-ATTRS |
| layout | root-layout, region | COMMON-ATTRS, CONTCTRL-ATTRS, type |
| root-layout | EMPTY | COMMON-ATTRS, backgroundColor, height, width, skip-content |
| region | EMPTY | COMMON-ATTRS, backgroundColor, bottom, fit, height, left, right, showBackground, top, width, z-index, skip-content, regionName |
| ref, animation, audio, img, video, text, textstream | area | COMMON-ATTRS, CONTCTRL-ATTRS, TIMING-ATTRS, repeat, MEDIA-ATTRS, region |
| a | MEDIA-ELMS | COMMON-ATTRS, LINKING-ATTRS |
| area | EMPTY | COMMON-ATTRS, LINKING-ATTRS, TIMING-ATTRS, repeat, shape, coords, nohref |
| par, seq | TIMING-ELMS, MEDIA-ELMS, switch, a | COMMON-ATTRS, CONTCTRL-ATTRS, TIMING-ATTRS, repeat |
| switch | TIMING-ELMS, MEDIA-ELMS, a, layout | COMMON-ATTRS, CONTCTRL-ATTRS |
Support of deprecated elements and attributes is required for SMIL 2.0 host language conformance for all modules the given language supports. For example, if a SMIL 2.0 host language supports the MultiArcTiming module, it must support the deprecated syntax defined in the MultiArcTiming module.
Since the SMIL 2.0 Structure module may only be used in a profile that is SMIL host language conformant, this implies that the SMIL 2.0 Structure module must at least be accompanied with the nine other modules required for host language conformance that were named above. Those modules themselves can still be used in other, non SMIL host language conformant, language profiles.
This section is normative.
A language profile is said to be SMIL 2.0 integration set conformant if it includes the following modules:
In addition, the following requirements must be satisfied:
| Element | Minimum Support | |
| Elements | Attributes | |
| ref, animation, audio, img, video, text, textstream | CONTCTRL-ATTRS, TIMING-ATTRS, MEDIA-ATTRS | |
| par, seq | TIMING-ELMS, MEDIA-ELMS, switch, a | CONTCTRL-ATTRS, TIMING-ATTRS |
| switch | TIMING-ELMS, MEDIA-ELMS | CONTCTRL-ATTRS |
Support of deprecated elements and attributes is not required for SMIL 2.0 integration set conformance. However, when included, the above requirements also apply to these elements and attributes. Also, when supported, it is required that all the deprecated elements and attributes from all the included modules are supported as a whole.
This section is informative.
A language profile is specified through its DTD or XML Schema. The identifier of these can be used to identify the language profile. SMIL 1.0 has specified the default namespace declaration on its root element, smil, as the decisive identifier for distinguishing it from other language profiles [SMIL10]. For that purpose SMIL 1.0 has specified
http://www.w3.org/TR/REC-smil
as the namespace identifier for SMIL 1.0.
This section is normative.
For the purpose of identifying the version and the language profile used, SMIL host language conformant documents must satisfy the following requirements:
This section is normative.
Syntax errors in a SMIL Host Language conformant document are handled according to the XML rules for well-formed or valid XML [XML10].
Semantic errors can arise at various levels. One is where the declared attribute values are of unknown value. Another is where the assembled presentation is (possibly) conflicting, as in a case where media objects are competing for display space or where they are synchronized ambiguously. These latter types, although maybe an error according to the author's intentions, are not considered an error and the user agent will present according to the resolution rules defined in this specification.
This section is normative.
Errors in attribute values might remain undetectable to the parser, because the value type is declared as CDATA, or because the value range is open ended, as in the case of events, for example. However, errors in attribute values can be detected within a given language profile, where that language profile specifies the supported value set. Specifications of language profiles are required to specify the error handling that is required when such an attribute value error occurs.
This section is informative.
This section describes how language profiles could be defined using the SMIL 2.0 modular DTDs. The reader is assumed to be familiar with the mechanisms defined in "Modularization of XHTML" [XMOD], in particular Appendix D [XMOD-APPD] and Appendix E [XMOD-APPE]. In general, the SMIL 2.0 modular DTDs use the same mechanisms as the XHTML modular DTDs use. Exceptions to this are:
Below, we give a short description of the files that are used to define the SMIL 2.0 modular DTDs. See the table and the end of the section for a complete list of the filenames involved.
Following the same mechanisms as the XHTML modular DTDs, the SMIL 2.0 specification places the XML element declarations (e.g. <!ELEMENT...>) and attribute list declarations (e.g. <!ATTLIST...>) of all SMIL 2.0 elements in separate files, the SMIL module files. A SMIL module file is provided for each functional area in the SMIL 2.0 specification (that is, there is a SMIL module file for animation, layout, timing, etc).
The SMIL module files are used in the normative definitions of the specification of the SMIL 2.0 Language Profile. Usage of the same module files for defining other SMIL profiles is recommended, but not required. The requirements that SMIL language profiles must follow are stated in the SMIL 2.0 specification, not in the DTD code.
To make the SMIL module files independent of each other, and independent of the language profiles, the element and attribute declarations make heavy use of XML entities. This provides profiles with the necessary hooks to define the actual content models and attributes of the SMIL elements.
The SMIL 2.0 Language Profile provides examples of how the SMIL module files can be used. Most of the DTD files are reused across the different profiles. Reused are the SMIL module files, the files that define the data types and the common attributes, the "qname" file that takes care of adding namespace prefixes if necessary, and the framework file, which takes care of including files in the appropriate order.
The files that are different for each profile are the driver file and document model file. This would, in general, also apply to new profiles: to define a new language profile, one has to write the extension module(s), the driver file that defines which modules are used, and a document model file that defines the extended document model. The driver file and document model file are described in more detail below.
The driver file.
This is the file that would be referenced by a document's DOCTYPE declaration. Its main job is to define which document model file and which of the SMIL module files the profile is using. It may also define an optional namespace to be used in all namespace prefixes. For example, to prefix all SMIL element names with "foobar", the following can be added to the start of the profile:
<!ENTITY % SMIL.prefixed "INCLUDE" >
<!ENTITY % SMIL.prefix "foobar" >
Elements defined in their modules as, for example, <video> will become parsed as <foobar:video>. This also applies for SMIL attributes that appear on other elements, so, for example, "begin" becomes "foobar:begin". The default is that the qname prefix is empty -- that is, it is effectively turned off by default.
After these definitions, the driver file includes the framework file (which will subsequently include the data type, common attributes, qname and document model file), after which the SMIL module files are included that are used by this profile.
The document model file.
The document model file contains the XML entities that are used by the SMIL module files to define the content models and attribute lists of the elements in that profile.
Content models generally differ from profile to profile, or contain elements from other modules. To avoid these dependencies in the SMIL module files, content models need to be defined in the document model file. The (dummy) default content model as defined in the SMIL module files is "EMPTY" for all SMIL 2.0 elements.
For the same reasons, the SMIL module files only define a default attribute list for their elements. This default list only contains the SMIL 2.0 core attributes and the attributes that are defined in the same SMIL module file. All other attributes need to be added to this default list by defining the appropriate XML entities. For example, the Media Objects Module file only adds the core and media related attributes on the media objects; other attributes, such as the timing attributes, are added to this list by the document model file.
| Driver files for the predefined profiles | |
| -//W3C//DTD SMIL 2.0//EN | http://www.w3.org/2001/SMIL20/SMIL20.dtd |
| Document model files for the predefined profiles | |
| -//W3C//ENTITIES SMIL 2.0 Document Model 1.0//EN | http://www.w3.org/2001/SMIL20/smil-model-1.mod |
| SMIL 2.0 module files | |
| -//W3C//ELEMENTS SMIL 2.0 Animation//EN | http://www.w3.org/2001/SMIL20/SMIL-anim.mod |
| -//W3C//ELEMENTS SMIL 2.0 Content Control//EN | http://www.w3.org/2001/SMIL20/SMIL-control.mod |
| -//W3C//ELEMENTS SMIL 2.0 Layout//EN | http://www.w3.org/2001/SMIL20/SMIL-layout.mod |
| -//W3C//ELEMENTS SMIL 2.0 Linking//EN | http://www.w3.org/2001/SMIL20/SMIL-link.mod |
| -//W3C//ELEMENTS SMIL 2.0 Media Objects//EN | http://www.w3.org/2001/SMIL20/SMIL-media.mod |
| -//W3C//ELEMENTS SMIL 2.0 Document Metainformation//EN | http://www.w3.org/2001/SMIL20/SMIL-metainformation.mod |
| -//W3C//ELEMENTS SMIL 2.0 Document Structure//EN | http://www.w3.org/2001/SMIL20/SMIL-struct.mod |
| -//W3C//ELEMENTS SMIL 2.0 Timing//EN | http://www.w3.org/2001/SMIL20/SMIL-timing.mod |
| -//W3C//ELEMENTS SMIL 2.0 Transition//EN | http://www.w3.org/2001/SMIL20/SMIL-transition.mod |
| Other utilities: data types, common attributes, qname and frame work files | |
| -//W3C//ENTITIES SMIL 2.0 Datatypes 1.0//EN | http://www.w3.org/2001/SMIL20/smil-datatypes-1.mod |
| -//W3C//ENTITIES SMIL 2.0 Common Attributes 1.0//EN | http://www.w3.org/2001/SMIL20/smil-attribs-1.mod |
| -//W3C//ENTITIES SMIL 2.0 Qualified Names 1.0//EN | http://www.w3.org/2001/SMIL20/smil-qname-1.mod |
| -//W3C//ENTITIES SMIL 2.0 Modular Framework 1.0//EN | http://www.w3.org/2001/SMIL20/smil-framework-1.mod |