Network Working Group S. Pfeiffer
Internet-Draft C. Parker
Expires: December 7, 2003 CSIRO
June 8, 2003
Specification of the Continuous Media Markup Language (CMML), Version
1.0
draft-pfeiffer-cmml-00
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026 except that the right to
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Copyright Notice
Copyright (C) The Internet Society (2003). All Rights Reserved.
Abstract
This specification defines the Continuous Media Markup Language
(CMML), version 1.0, an XML-based [1] markup language for
time-continuous data. It is a sister document to the specification
of the ANNODEX(TM) [12] annotation and indexing format for
time-continuous data. The CMML is an authoring language for
annotating, indexing and hyperlinking time-continuous data in the
ANNODEX(TM) [12] format. Its tags provide for the creation of
structured and unstructured annotations as well as hyperlinks and
addressable named anchor points for fragments of time-continuous
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data. The tag names in use in CMML are similar to the ones in XHTML
[3].
At this point in time, the right to produce derivative works is not
granted to the IETF as the authors are uncertain about the necessity
to create a working group. The specification is not encumbered by
patents. The ANNODEX(TM) format is protected by a trademark to
prevent the use of the term "annodex" for any related but
non-conformant and therefore non-interoperable technology.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. The CMML data types . . . . . . . . . . . . . . . . . . . . . 5
2.1 URIs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Internationalisation support . . . . . . . . . . . . . . . . . 5
2.3 Time specifications . . . . . . . . . . . . . . . . . . . . . 5
3. The preamble and the 'cmml' root element . . . . . . . . . . . 8
4. The cmml 'stream' tag . . . . . . . . . . . . . . . . . . . . 9
4.1 The 'media' tag . . . . . . . . . . . . . . . . . . . . . . . 9
5. The cmml 'head' element . . . . . . . . . . . . . . . . . . . 11
5.1 The 'title' element . . . . . . . . . . . . . . . . . . . . . 11
5.2 The 'base' element . . . . . . . . . . . . . . . . . . . . . . 12
5.3 The 'meta' element . . . . . . . . . . . . . . . . . . . . . . 12
6. The cmml 'a' tag . . . . . . . . . . . . . . . . . . . . . . . 13
6.1 The 'meta' element . . . . . . . . . . . . . . . . . . . . . . 14
6.2 The 'desc' element . . . . . . . . . . . . . . . . . . . . . . 14
7. The mapping of CMML to ANNODEX(TM) format bitstreams . . . . . 16
8. MIME media type registration for 'text/cmml' . . . . . . . . . 17
9. Security considerations . . . . . . . . . . . . . . . . . . . 19
References . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 21
A. CMML DTD . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
B. An example CMML document . . . . . . . . . . . . . . . . . . . 27
C. Definitions of terms and abbreviations . . . . . . . . . . . . 28
D. Glossary of acronyms . . . . . . . . . . . . . . . . . . . . . 29
E. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 30
Intellectual Property and Copyright Statements . . . . . . . . 31
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1. Introduction
Please note that this document assumes that the reader has a fluent
working knowledge of XML [1], HTML [2], XHTML [3] and the World Wide
Web. Knowledge about the ANNODEX(TM) [12] sister document is also
presumed.
Time-continuous data in the ANNODEX(TM) format contains XML-based
annotations and hyperlinking information that enables it to be
browsed by client applications, and crawled and indexed by search
engines. The Continuous Media Markup Language CMML is a simple
markup language for authoring the XML data to be multiplexed with the
time-continuous data given in binary bitstreams. This process
eventually creates ANNODEX(TM) format bitstreams. The CMML has much
in common with XHTML.
The CMML can describe one or several time-continuous media
bitstreams. It is used to create all the tags required for authoring
the annotation information for the ANNODEX(TM) format. It therefore
basically contains the same tags as the annotation bitstream in
ANNODEX(TM) format bitstreams, but also has some additional tags
required for identifying and synchronising one or several
time-continuous bitstreams that will be multiplexed together for the
creation of one conherent ANNODEX(TM) format bitstream.
The following picture illustrates the multiplexing activity:
----------
|stream | CMML
---------- instance
| head | document
----------
|anchor_1| ----------------------------------------------------
---------- | media bitstream in packets |
| ... | ----------------------------------------------------
---------- |
|anchor_n| |
---------- |
| |
------->-<-------
|
Multiplexing
|
v
----------------------------------------------------------------------
|stream|head|anchor_1| media packets |anchor_2| media packets ...
----------------------------------------------------------------------
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The file extension of CMML files is ".cmml". This document also
applies for registration of the mime-type "text/cmml" for CMML files.
The CMML is technically fully specified through its DTD as given in
the Appendix. The semantic meaning of each of the tags, their
content and their attributes is specified in the following sections.
The Appendix also contains an example of a CMML (instance) document.
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2. The CMML data types
At the beginning of the CMML DTD, several parameter entities are
defined that are used throughout the DTD as data types. This section
gives a brief overview of them and refers to the relevant standards
in which they are defined.
2.1 URIs
A "URI" is a character string that conforms to the specification of
the Uniform Resource Identifier as defined in RFC 2396 [4]. The
currently proposed temporal URI fragment identifier specification
[11] is supported, too. A URI generally points to a Web resource.
2.2 Internationalisation support
The "LanguageCode" defines a collection of constant strings that each
identify a specific language as defined in RFC 1766 [6]. It is used
to provide internationalisation support. To that end, the i18n
entity draws together a language given by a "LanguageCode" with the
directionality of that language in "dir" given either as ltr
(left-to-right) or rtl (right-to-left).
2.3 Time specifications
There are three different time specifications in use in CMML:
"Timestamp", "Playbacktime" and "UTCtime".
A "Timestamp" is generally a name-value pair which defines a time
point. The time point value is interpreted according to the time
scheme given in the name. If the name is ommitted, it defaults to
"npt=". The available time specifications stem from different
sources:
o "npt" is "normal playback time" as used in the RTSP standard [5].
o "smpte" are several frame-based time labels as defined by the
Society of Motion Pictures and Television Engineers [9]. As
fractional frames are meaningless for video and ambiguous for
audio in the drop-frame situations, they are not used. The
drop-frame algorithms for calculating the exact times can be found
in the mentioned SMPTE standard.
o "utc" is the "universal time code" as specified in the ISO 8601
standard [10].
Thus, the available time schemes are:
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"npt=" NPT time with a second or subsecond basis
Specification as BNF:
npt-spec = "npt=" npt-time
npt-time = npt-sec | npt-hhmmss
npt-sec = 1*DIGIT [ "." *DIGIT ]
npt-hhmmss = npt-hh ":" npt-mm ":" npt-ss [ "." *DIGIT ]
npt-hh = 1*DIGIT
npt-mm = 1*2DIGIT
npt-ss = 1*2DIGIT
"smpte-24=" SMPTE time with a 24 fps basis
"smpte-24-drop=" SMPTE time with a 24/1.001 fps basis
"smpte-25=" SMPTE time with a 25 fps basis
"smpte-30=" SMPTE time with a 30 fps basis
"smpte-30-drop=" SMPTE time with a 30/1.001 fps basis
"smpte-50=" SMPTE time with a 50 fps basis
"smpte-60=" SMPTE time with a 60 fps basis
"smpte-60-drop=" SMPTE time with a 60/1.001 fps basis
Specification as BNF:
smpte-spec = smpte-type "=" smpte-time
smpte-type = "smpte-24" | "smpte-24-drop" | "smpte-25" |
"smpte-30" | "smpte-30-drop" | "smpte-50" |
"smpte-60" | "smpte-60-drop"
smpte-time = 1*2DIGIT ":" 1*2DIGIT ":" 1*2DIGIT [ ":" 1*2DIGIT ]
"clock=" UTC time with a second or subsecond basis
Specification as BNF:
utc-spec = "clock=" utc-time
utc-time = utc-date "T" utc-hhmmss "Z"
utc-date = 8DIGIT
utc-hhmmss = 6DIGIT [ "." *DIGIT ]
The "Playbacktime" entity is a data type that just specifies a SMPTE
or a NPT time. It is therefore equal to the Timestamp entity without
the UTC specification.
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The "UTCtime" entity is a data type that just specifies a UTC time
without an identifier. UTC time is specified as in the Timestamp
entity, but without the "clock=" identifier.
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3. The preamble and the 'cmml' root element
A CMML file is an XML instance document of the CMML DTD. An example
is given in the Appendix. It starts with the usual xml directive and
the DTD specification (see http://www.w3.org/TR/
REC-xml#sec-prolog-dtd). This is an example preamble:
<?xml version="1.0"encoding="UTF-8"?>
<!DOCTYPE cmml SYSTEM "cmml.dtd">
After the preamble, the CMML tags follow. A CMML file has a "cmml"
tag as the root element. It embraces all the other tags.
<!ELEMENT cmml (stream?, head, a*)>
<!ATTLIST cmml
id ID #IMPLIED
xmlns %URI; #FIXED 'http://www.annodex.net/cmml'
>
The "cmml" tag encloses at most one "stream" element, exactly one
"head" element, and as many "a" elements as the document author
requires. An "a" element describes a fragment of the to be created
ANNODEX(TM) bitstream. The ANNODEX(TM) bistream is created by
multiplexing the bitstreams given in the "location" attributes of the
"media" tags of the "stream" element together with the CMML
annotations in a time-synchronous manner, as specified in the
ANNODEX(TM) format [12].
Attributes of the "cmml" element are the usual xml root tag
attributes: an identifier "id" and a namespace "xmlns".
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4. The cmml 'stream' tag
The "stream" element contains information about the input
time-continuous bitstreams that are to be multiplexed together on
authoring the ANNODEX(TM) format bitstreams.
<!ELEMENT stream (media*)>
<!ATTLIST stream
id ID #IMPLIED
timebase %Playbacktime; "npt=0"
utc %UTCtime; #IMPLIED
>
The "timebase" attribute contains a playback time in seconds
associated with that first data packet. All other times in the CMML
file MUST be calculated relative to this timebase. For example, a
timebase of 300 seconds npt for a video file implies that the first
frame is related to a play time of 300 seconds, and an anchor with a
start time of 350 seconds is to be included 50 seconds into the
ANNODEX(TM) bitstream. If no timebase is given, the timebase
defaults to 0 npt. The timebase can be given as a SMPTE or NPT time,
not as a utc time.
The "utc" attribute associates a calendar date and a wall-clock time
with the timebase. It therefore provides a mapping of the timebase
to a real-world clock time and is given as a UTC time. If it is
omitted, the start attribute in the media tag, and the start and end
attributes in anchor tags MUST NOT be specified as UTC times.
The content model of the "stream" tag then proposes an arbitrary
number of input bitstreams. These are described one by one in the
"media" element.
4.1 The 'media' tag
A "media" tag contains information on one of the input bitstreams for
the multiplexing process. The relevant bitstream (fragment) is
referenced through the "location" attribute. The location is a URI
and may thus also contain a temporal URI fragment specification which
narrows down the input file to that given subpart. That resource is
multiplexed into the ANNODEX(TM) format bitstream starting at the
time given in the "start" attribute and ending at the latest at the
time given in the "end" attribute. The "start" and "end" attributes
are interpreted relative to the timeline of the ANNODEX(TM) format
bitstream.
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<!ELEMENT media EMPTY>
<!ATTLIST media
id ID #IMPLIED
granulerate CDATA #IMPLIED
mimetype CDATA #IMPLIED
location %URI; #REQUIRED
start %Timestamp; "npt=0"
end %Timestamp; #IMPLIED
>
The "granulerate" attribute contains the base temporal resolution in
Hz of the input bitstream refered in the "location" attribute. It
depends on the encoding format of the input bitstream and typically
contains the framerate for video (e.g. 25 frames/sec) and the
samplerate for audio (e.g. 44100 samples/sec), but may contain any
rational number given with an integer denominator larger than 1 sec
(e.g. 25 frames on 2 seconds). Each bitstream has its own
granulerate dependent on its specific encoding. This attribute is
implied as it can be determined automatically during the multiplexing
process when the headers of the encoded media bitstream contain this
information. For bitstreams without header, such as uncompressed
audio, the author of the CMML file can provide the granulerate to the
multiplexer in this attribute.
The "mimetype" attribute specifies the MIME type [7] of the input
bitstream refered in the "location" attribute. It is optional as the
MIME type can often be derived easily from the file name or file
header of the media source during multiplexing.
The "location" attribute specifies a URI to the input bitstream.
Commonly used URI schemes are "file" and "http". For specifying
temporal subsets of the input bitstream, use the temporal URI
fragment [11] specification.
The "start" attribute specifies a time in the output ANNODEX(TM)
bitstream at which the media bitstream will be inserted. This time
is specified with respect to the "timebase" attribute given in the
"stream" element.
The "end" attribute specifies a time in the output ANNODEX(TM)
bitstream at which the media bitstream stop at the latest. This time
is also specified with respect to the "timebase" attribute given in
the "stream" element. This attribute is not required when the full
bitstream is used.
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5. The cmml 'head' element
The CMML "head" element contains annotation information on the
complete ANNODEX(TM) bitstream, which the CMML file is used to
create. It therefore contains header-type information such as a
title for the bitstream, and meta information describing the
bitstream.
The "head" element is declared as the following:
<!ELEMENT head (meta*,
((title, meta*, (base, meta*)?) |
(base, meta*, (title, meta*)?)))>
<!ATTLIST head
id ID #IMPLIED
%i18n;
defltlang %LanguageCode; #IMPLIED
defltdir (ltr|rtl) #IMPLIED
profile %URI; #IMPLIED
>
The "head" tag must contain a "title" tag. It may contain one "base"
tag before or after the "title" tag and any number of "meta" tags at
any position.
The "%i18n;" attribute specifies the base language of the "head"
tag's attribute values.
The "defltlang" and "defltdir" attributes specify the default
language (language and directionality) of the anchor tags.
The value of the "profile" attribute is a space-separated list of
base URIs specifying locations of "meta" tag schemes. These schemes
may be used in the "meta" elements of the "head" or the "a" tags.
5.1 The 'title' element
The "title" tag gives a descriptive title for the ANNODEX(TM)
bitstream. The "title" element is declared as the following:
<!ELEMENT title (#PCDATA)>
<!ATTLIST title
id ID #IMPLIED
%i18n;
>
The "%i18n;" attribute specifies the base language of the "title"
text.
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5.2 The 'base' element
The "base" element defines the base URI of the ANNODEX(TM) bitstream.
All relative URIs of the bitstream get interpreted relative to this
base. The "base" element is empty, but its attributes contain the
base URI. It is declared as follows:
<!ELEMENT base EMPTY>
<!ATTLIST base
id ID #IMPLIED
href %URI; #REQUIRED
>
The "href" attribute contains the base URI.
5.3 The 'meta' element
The "meta" element defines structured annotations for the complete
ANNODEX(TM) bitstream. A "meta" element is empty, but its attributes
contain the name-value pairs of a structured annotation. The "meta"
element is declared as follows:
<!ELEMENT meta EMPTY>
<!ATTLIST meta
id ID #IMPLIED
%i18n;
name NMTOKEN #IMPLIED
content CDATA #REQUIRED
scheme CDATA #IMPLIED
>
The "%i18n;" attribute specifies the default language of the meta
attribute and content texts.
The "name" attribute identifies a property name. It does not list
legal values for this attribute.
The "content" attribute specifies a property's value. It does not
list legal values for this attribute.
The "scheme" attribute names a scheme to be used to interprete the
property's value. The scheme can be located via the "profile"
attribute in the "head" element.
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6. The cmml 'a' tag
A CMML file typically contains a number of anchors given in "a" tags.
The CMML "a" tag contains information about a fragment of the
ANNODEX(TM) bitstream. This is expressed in a number of elements and
attributes annotating, indexing, and hyperlinking the fragment. The
"start" and "end" attributes are used to give the insertion time for
the anchor into the ANNODEX(TM) bitstream.
<!ELEMENT a (meta*, desc*)>
<!ATTLIST a
id ID #IMPLIED
%i18n;
track CDATA "default"
href %URI; #IMPLIED
hrefdesc CDATA #IMPLIED
image %URI; #IMPLIED
start %Timestamp; #REQUIRED
end %Timestamp; #IMPLIED
>
Any number of "meta" and "desc" elements may appear in an anchor
page, but the "meta" elements must all appear first and en bloc,
while the "desc" elements must all appear last and also en bloc.
An "a" element defines a name for the fragment in the "id" attribute.
This name can be used in URIs that point either to the CMML file or
the ANNODEX(TM) bitstream created from it. It will be used as a
fragment identifier and point straight to the fragment defined by the
"a" tag.
The "%i18n;" attribute specifies the default language used by all the
"desc" elements of the "a" tag.
The "track" attribute specifies the track that this anchor belongs
to. An annotation track is a set of "a" pages that belong together
from a semantic point of view. Anchors in the same track must not
overlap temporally. A default track must be available always. This
track is the one a client (such as a Web browser plugin) will display
by default. Other annotation tracks may be created by the document
author to describe a more specific content. An example use are
different annotation tracks for each speaker in an audio recording of
a meeting.
The "href" attribute specifies the location of a Web resource given
by a URI. It thus defines a link between the current fragment and a
resource which the author believes to be connected closely to this
fragment's content. This might be a html page or another ANNODEX(TM)
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bitstream fragment or an image etc.
The "hrefdesc" attribute gives a short textual description of the
link specified through the "href" attribute. It explains why the
connection between the current fragment and the destination URI is
made. It may e.g. encourage the viewer to follow the link to "Get
more information on blah". This attribute value can be specified
only if the "href" attribute has been specified.
The "image" attribute specifies the location of an image on the Web
given by a URI. This image should be quite small as it is the
representative image (known as "keyframe") for the current fragment.
This image may be used to visually summarise the content of the
fragment when a link to it is displayed, e.g. by a search engine or
in a table of contents.
The "start" and "end" attributes specify the time range during which
the anchor element is defined. This time range is specified with
respect to the "timebase" and "utc" attributes given in the "stream"
tag. If the "stream" tag does not contain a "utc" specification,
"start" and "end" times are not allowed to be given in UTC time.
"start" is a required attribute because an achor without a start time
is useless. "end" is optional and only required where anchors cannot
continue on to the following anchor.
6.1 The 'meta' element
The "meta" element is specified above in the "head" section. While a
"meta" element in the "head" tag provides meta information for the
complete ANNODEX(TM) bitstream, the "meta" elements in an "a" tag
only provide meta information for the anchor.
6.2 The 'desc' element
The "desc" tag contains a human readable, textual description (or
annotation) of the content of the fragment. The "desc" element is
declared as the following:
<!ELEMENT desc (#PCDATA)>
<!ATTLIST desc
id ID #IMPLIED
%i18n;
>
For extracting a short text from the "desc" element as needs to be
displayed in a table of contents or as caption, the first few
characters of the description will be taken. It therefore is
recommended to place a short meaningful summary sentence at the
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beginning of the description when authoring annotations.
The "%i18n;" attribute specifies the actual language of the text in
the description. So, if it is required to give a mixed language
description, the default language will be given in the "%i18n;"
attribute of the "a" tag and the actually used language in a specific
"desc" tag is given there.
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7. The mapping of CMML to ANNODEX(TM) format bitstreams
As CMML is an authoring format for ANNODEX(TM) format bitstreams,
there is a simple way to map the annotations and meta information
contained in a CMML instance document to the annotation bitstreams
and header fields of an ANNODEX(TM) format bitstream.
There is a direct mapping between a CMML "head" element and an
ANNODEX(TM) "head" page as they both contain the same elements and
the same attributes. The additional namespace attribute "xmlns" in
the "head" page of an ANNODEX(TM) format bitstream will be filled
from the "xmlns" attribute of the "cmml" tag of the CMML file and
defaults to the same namespace default.
There is also a direct mapping between a CMML "a" element and an
ANNODEX(TM) "a" page as they also both contain the same elements and
the same attributes, except for the "start" and "end" attributes.
The "start" attribute tells the multiplexer that creates the
ANNODEX(TM) format bitstream at what time to insert the "a" page into
the bitstream. The "end" attribute (if present) leads to the
creation of an "empty" "a" page on the same track at the given time
in the ANNODEX(TM) format bitstream unless another "a" page apears on
the same track beforehand. The "empty" "a" page contains no
attribute values for any of the implied attributes and no "meta" or
"desc" elements, but has a copy of the "track" attribute. Again, the
"xmlns" attribute is filled from the "xmlns" attribute of the "cmml"
tag of the CMML file and defaults to the same namespace default.
The information contained in a CMML "stream" element is partly
relevant to authoring only and partly required in different binary
header fields of an ANNODEX(TM) format bitstream. The "stream"
attributes "timebase" and "utc" are stored in the bos page of the
ANNODEX(TM) media mapping bitstream. Each of the encapsulated media
bitstreams is described by one of the "media" tags in the CMML.
Their "id", "granulerate" and "mimetype" attributes are stored in the
bos page of the respective bitstreams. The other attributes of the
"media" tag are used for authoring only and therefore not mapped to a
field in the ANNODEX(TM) format bitstream.
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8. MIME media type registration for 'text/cmml'
This section contains the registration information for the 'text/
cmml' media type. While this media type is not approved by the IANA,
'text/x-cmml' may be used to identify CMML instance documents.
To: ietf-types@iana.org
Subject: Registration of MIME media type 'text/cmml'
MIME media type name: text
MIME subtype name: cmml
Required parameters: none
Optional parameters: charset (as in the text/xml media type [8]).
Encoding Considerations: as appropriate for the charset and the
transport mechanism (see text/xml media type [8]).
Security considerations: see next section.
Interoperability considerations: CMML is a free specification that is
independent of any media encoding format. It is designed to provide
interoperability with existing XML tools and systems. Its
specification is not patented and can be implemented by third parties
without patent considerations.
Additional information:
Magic numbers: none. However, CMML files start with the XML
preamble as any XML document [8]) and will also have the string
'<cmml' near the beginning of the file.
File extension: .cmml
Macintosh File Type Code: "TEXT"
Intended usage: COMMON
Fragment identifiers: Any named element, i.e. element that contains
an "id" attribute, may be referenced through a fragment identifier of
a URI. However, the values of the id attribute of the anchor tags
are the most important ones used for addressing media fragments.
Also, the generic temporal addressing scheme proposed for
standardisation [11] can be used as a fragment address and then
relates to the last anchor whose start time is just before the given
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temporal offset.
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9. Security considerations
As CMML is a markup language created by using XML, the same security
considerations that apply to XML [8], apply to CMML.
As the CMML is an authoring language for ANNODEX(TM) format
bitstreams, there is no executable code attached to this language.
The implementation of a multiplexer to actually create an ANNODEX(TM)
bitstream must be careful when handling input bitstreams, which are
binary data.
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References
[1] World Wide Web Consortium, "Extensible Markup Language (XML)
1.0", W3C XML, October 2000, <http://www.w3.org/TR/2000/
REC-xml-20001006>.
[2] World Wide Web Consortium, "HTML 4.01 Specification", W3C HTML,
December 1999, <http://www.w3.org/TR/html4/>.
[3] World Wide Web Consortium, "XHTML(TM) 1.0 The Extensible Hyper
Text Markup Language", W3C XHTML, January 2000, <http://
www.w3.org/TR/xhtml1/>.
[4] Berners-Lee, T., Fielding, R. and L. Masinter, "Uniform
Resource Identifiers (URI): Generic Syntax", RFC 2396, August
1998, <http://www.ietf.org/rfc/rfc2396.txt>.
[5] Schulzrinne, H., Rao, A. and R. Lanphier, "Real Time Streaming
Protocol (RTSP)", RFC 2326, April 1998, <Http://www.ietf.org/
rfc/rfc2326.txt>.
[6] Alvestrand, H., "Tags for the Identification of Languages", RFC
1766, March 1995, <http://www.ietf.org/rfc/rfc1766.txt>.
[7] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part Two: Media Types", RFC 2046, November
1996, <http://www.ietf.org/rfc/rfc2046.txt>.
[8] Whitehead, E. and M. Murata, "XML Media Types", RFC 2376, July
1998, <http://www.ietf.org/rfc/rfc2376.txt>.
[9] The Society of Motion Picture and Television Engineers, "SMPTE
STANDARD for Television, Audio and Film - Time and Control
Code", ANSI 12M-1999, September 1999.
[10] ISO, TC154., "Data elements and interchange formats --
Information interchange -- Representation of dates and times",
ISO 8601, 2000.
[11] Pfeiffer, S. and C. Parker, "Syntax of temporal URI fragment
specifications (work in progress)", I-D
draft-pfeiffer-temporal-fragments-01.txt, Feburary 2003,
<http://www.ietf.org/internet-drafts/
draft-pfeiffer-temporal-fragments-01.txt>.
[12] Pfeiffer, S. and C. Parker, "Specification of the ANNODEX(TM)
annotation and indexing format for time-continuous data files,
Version 1.0 (work in progress)", I-D
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draft-pfeiffer-annodex-00.txt, June 2003, <http://
www.annodex.net/TR/annodex.txt>.
Authors' Addresses
Silvia Pfeiffer
Commonwealth Scientific and Industrial Research Organisation CSIRO, Australia
Locked Bag 17
North Ryde, NSW 2113
Australia
Phone: +61 2 9325 3141
EMail: Silvia.Pfeiffer@csiro.au
URI: http://www.cmis.csiro.au/Silvia.Pfeiffer/
Conrad D. Parker
Commonwealth Scientific and Industrial Research Organisation CSIRO, Australia
Locked Bag 17
North Ryde, NSW 2113
Australia
Phone: +61 2 9325 3133
EMail: Conrad.Parker@csiro.au
URI: http://www.cmis.csiro.au/Conrad.Parker/
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Appendix A. CMML DTD
<?xml version="1.0" encoding="UTF-8" ?>
<!--
Continuous Media Markup Language CMML version 1.0 DTD
Authoring language for ANNODEX(TM) media.
Namespace = http://www.annodex.net/cmml
Copyright (c) 2001
Commonwealth Scientific and Industrial Research Organisation
(CSIRO), Australia.
All Rights Reserved.
This DTD module is identified by the PUBLIC and SYSTEM identifiers:
PUBLIC "-//CSIRO//DTD CMML 1.0//EN"
SYSTEM "http://www.annodex.net/DTD/cmml_1_0.dtd"
$Revision: 1.0 $
$Date: 2003/06/01 24:00:00 $
-->
<!-- **************************** -->
<!-- Definition of Imported Names -->
<!-- **************************** -->
<!-- a Uniform Resource Identifier, see [RFC2396] -->
<!ENTITY % URI "CDATA">
<!-- a language code, as per [RFC1766] -->
<!ENTITY % LanguageCode "NMTOKEN">
<!-- internationalization attributes
xml:lang language code (as per XML 1.0 spec)
dir direction for weak/neutral text
-->
<!ENTITY % i18n
"lang %LanguageCode; #IMPLIED
dir (ltr|rtl) #IMPLIED"
>
<!-- timestamps similar to [RFC2326]
"smpte-24=" SMPTE time with a 24 fps basis
"smpte-24-drop=" SMPTE time with a 24/1.001 fps basis
"smpte-25=" SMPTE time with a 25 fps basis
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"smpte-30=" SMPTE time with a 30 fps basis
"smpte-30-drop=" SMPTE time with a 30/1.001 fps basis
"smpte-50=" SMPTE time with a 50 fps basis
"smpte-60=" SMPTE time with a 60 fps basis
"smpte-60-drop=" SMPTE time with a 60/1.001 fps basis
"npt=" npt-time
"clock=" utc-time
Playbacktime is specified as a smpte-time
or npt-time only.
UTCtime is specified as in [RFC2326], but
without the "clock" identifier
-->
<!ENTITY % Timestamp "CDATA">
<!ENTITY % Playbacktime "CDATA">
<!ENTITY % UTCtime "CDATA">
<!-- **************************** -->
<!-- Document Structure -->
<!-- **************************** -->
<!-- ROOT ELEMENT: -->
<!-- cmml tag containing sequence of head and a tags -->
<!-- =============================================== -->
<!-- xmlns = namespace of the cmml tags -->
<!-- (language of this is covered by the default language
given in the head element) -->
<!ELEMENT cmml (stream?, head, a*)>
<!ATTLIST cmml
id ID #IMPLIED
xmlns %URI; #FIXED 'http://www.annodex.net/cmml'
>
<!-- **************************** -->
<!-- Definition of stream element -->
<!-- **************************** -->
<!-- STREAM tag providing timing information for the ANNODEX file -->
<!-- (will be stored in the binary headers of the ANX bitstreams) -->
<!-- ============================================================ -->
<!-- timebase = base time associated with the first frame of the media
document from which subsequent time references (such as
in anchor tags) will be taken relative to -->
<!-- utc = a mapping of the first frame to clock time;
specifications of utc time offsets into the document as
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in a URI will be taken relative to this -->
<!ELEMENT stream (media*)>
<!ATTLIST stream
id ID #IMPLIED
timebase %Playbacktime; "npt=0"
utc %UTCtime; #IMPLIED
>
<!-- MEDIA tag giving descriptions on a media bitstream (empty content) -->
<!-- ================================================================== -->
<!-- granulerate = the base temporal resolution of the bitstream (.e.g.
its framerate for video or samplerate for audio) -->
<!-- mimetype = encoding format of the media document (a MIME type) -->
<!-- location = URI to the media document -->
<!-- start = the start time of the media bitstream specified
in location -->
<!ELEMENT media EMPTY>
<!ATTLIST media
id ID #IMPLIED
granulerate CDATA #IMPLIED
mimetype CDATA #IMPLIED
location %URI; #REQUIRED
start %Timestamp; "npt=0"
end %Timestamp; #IMPLIED
>
<!-- **************************** -->
<!-- Definition of document head -->
<!-- **************************** -->
<!-- head tag containing description of a specific media document -->
<!-- ============================================================ -->
<!-- profile = space-separated list of URIs to locate meta tag schemes -->
<!-- i18n = the base language of the head's attribute values and text
content -->
<!-- defltlang & defltdir = the default language for the whole document -->
<!ELEMENT head (meta*,
((title, meta*, (base, meta*)?) |
(base, meta*, (title, meta*)?)))>
<!ATTLIST head
id ID #IMPLIED
%i18n;
defltlang %LanguageCode; #IMPLIED
defltdir (ltr|rtl) #IMPLIED
profile %URI; #IMPLIED
>
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<!-- TITLE tag giving descriptive title of the media document -->
<!-- ========================================================= -->
<!-- i18n = the base language of the title -->
<!ELEMENT title (#PCDATA)>
<!ATTLIST title
id ID #IMPLIED
%i18n;
>
<!-- BASE URI of the document (empty content) -->
<!-- ======================================== -->
<!-- href = URI associated with the document; all relative URI references
get interpreted relative to this base -->
<!ELEMENT base EMPTY>
<!ATTLIST base
id ID #IMPLIED
href %URI; #REQUIRED
>
<!-- META description tags of the document (empty content) -->
<!-- ===================================================== -->
<!-- i18n = the default language for the meta attribute and content text -->
<!-- name = identifies a property name; does not list legal values for this
attribute -->
<!-- content = specifies a property's value; does not list legal values for
this attribute -->
<!-- scheme = names a scheme to be used to interpret the property's value
(see the profiles tag in the head element for locating these) -->
<!ELEMENT meta EMPTY>
<!ATTLIST meta
id ID #IMPLIED
%i18n;
name NMTOKEN #IMPLIED
content CDATA #REQUIRED
scheme CDATA #IMPLIED
>
<!-- **************************** -->
<!-- Definition of anchor tags -->
<!-- **************************** -->
<!-- A tag containing information for a specific fragment -->
<!-- ==================================================== -->
<!-- i18n = default language for all the desc tags in the anchor -->
<!-- track = defines different sets of anchor tags; anchor tags of same
type cannot overlap temporally-->
<!-- href = specifies the location of a Web resource, thus defining a
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link between the current element (the source anchor) and the
destination anchor given by this attribute -->
<!-- hrefdesc = textual description of the link between the current element
(the source anchor) and the destination anchor given by the
href attribute -->
<!-- image = link to an image that is representative for this fragment -->
<!-- start = specifies the start time of the fragment; specified in
time relative to the timebase of the header
[NOT INCLUDED IN ANNODEXED DOCUMENT] -->
<!-- end = specifies the end time of the fragment; specified in
time relative to the timebase of the header
[NOT INCLUDED IN ANNODEXED DOCUMENT] -->
<!ELEMENT a (meta*, desc*)>
<!ATTLIST a
id ID #IMPLIED
%i18n;
track CDATA "default"
href %URI; #IMPLIED
hrefdesc CDATA #IMPLIED
image %URI; #IMPLIED
start %Timestamp; #REQUIRED
end %Timestamp; #IMPLIED
>
<!-- DESC human-readable, textual description of the anchor (annotation) -->
<!-- =================================================================== -->
<!-- i18n = language of the data in the description, as per [RFC1766] -->
<!ELEMENT desc (#PCDATA)>
<!ATTLIST desc
id ID #IMPLIED
%i18n;
>
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Appendix B. An example CMML document
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE cmml SYSTEM "cmml_1_0.dtd">
<cmml>
<stream timebase="npt=0" utc="19911222T210000.00Z"/>
<media location="matrix.mpg" mimetype = "video/mpeg"
granulerate="25/1" start="npt=0"/>
</stream>
<head lang="en" defltlang="de">
<title lang="en">The Matrix</title>
<base href="http://www.foo.bar/"/>
<meta name="Movie" content="The Matrix"/>
<meta name="Producer" content="Joel Silver"/>
<meta name="Director" content="Larry Wachowski"/>
<meta name="Director" content="Andy Wachowski"/>
<meta name="Writer" content="The Wachowski Brothers"/>
</head>
<a id="no_spoon"
lang="en"
href="http://www.blah.au/spoons.anx#@bent"
hrefdesc="More images of the bent spoon"
image="no_spoon.jpg"
start="npt=46:5.9"
end="npt=51:3.4">
<meta name="Actor" content="Keanu Reeves"/>
<meta name="Actor" content="Rowan Witt"/>
<meta name="Cast.Reeves" content="Thomas A. Anderson/Neo"/>
<meta name="Cast.Witt" content="Spoon boy"/>
<meta name="Scene" content="Oracle"/>
<desc>There is no spoon: Neo is waiting to see the Oracle in a room
full of children doing seemingly impossible things. One is making
spoons bend through telekenesis. Neo tries to do it himself, but
fails. Spoon boy: "Do not try and bend the spoon that's impossible,
instead only try to realize the truth." Neo: "What truth?" Spoon
boy: "There is no spoon." Neo: "There is no spoon?" Spoon boy: "Then
you'll see that it is not the spoon that bends, it is only
yourself." Neo tries again...
</desc>
<desc lang="de">Den Löffel gibt es nicht: Neo entdeckt beim Besuch
des Orakels wie unwirklich seine Welt ist. Beim Versuch, einen
Löffel durch Telekinese zu verbiegen, bekommt er von dem Kind den
Rat: "Den Löffel gibt es nicht."
</desc>
</a>
</cmml>
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Appendix C. Definitions of terms and abbreviations
Anchor: A subpart of a resource covering some temporal interval.
Mark-up: XML tags and their content used to describe a media
document.
Annotating: the task of giving textual descriptions to fragments of
media documents.
Indexing: the task of identifying index points for media documents or
fragments thereof.
Hyperlinking: the task of linking from one Web resource to another.
If a link has a fragment offset into the resource, this is
sometimes called deep hyperlinking.
Track: a set of Anchor pages representing semantically correlated
annotations of a time-continuous resource.
ANNODEX(TM) bitstream: A specific file format for storing annotation,
hyperlinking, and indexing information multiplexed together with
the time-continuous data bitstreams they describe.
Bitstream: a sequence of data containing samples of time-continous
data.
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Appendix D. Glossary of acronyms
ANNODEX(TM): Annotated and indexed bitstream format.
CMML: Continuous Media Markup Language.
DTD: Document Type Declaration.
XML: eXtensible Markup Language.
Web: World Wide Web.
URI: Unified Resource Identifier.
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Appendix E. Acknowledgements
The authors greatly acknowledge the contributions of Andre Pang,
Andrew Nesbit, and Simon Lai in developing this standard.
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HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
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