Simple Delivery Profile for Closed Captions (US)

Table of Contents

• 1. Conformance Introduction
• 2. Terms Terms, Definitions, and Definitions Conventions
• 3. Simple Delivery Profile for Closed Captions 3.1 Use of TTML Constrained Feature Template Conformance
• 4. Structural Constraints 5. Constrained Features
  • 5.1 Use of Constrained TTML Feature core 5.1.1 Usage Scenario 5.1.2 Constraints 5.2 Use of Constrained TTML Feature content 5.2.1 Usage Scenario 5.2.2 Constraints 5.3 4.1 Use of Constrained TTML Feature presentation 5.3.1 #content Usage Scenario 5.3.2 Constraints
  • 5.4 Use of Constrained TTML Feature profile 5.4.1 Usage Scenario 5.4.2 Constraints 5.5 4.2 Use of Constrained TTML Feature structure 5.5.1 #profile Usage Scenario 5.5.2 Constraints
• 6. 5. Style Constraints
  • 6.1 5.1 Use of Constrained TTML Feature backgroundColor-* 6.1.1 #backgroundColor-* Usage Scenario 6.1.2 Constraints
  • 6.2 5.2 Use of Constrained TTML Feature color #color 6.2.1 Usage Scenario
  • 6.2.2 Constraints 6.3 5.3 Use of Constrained TTML Feature display-region #extent-region
    • 6.3.1 Usage Scenario 6.3.2 5.3.1 Constraints Examples
  • 6.4 5.4 Use of Constrained TTML Feature display-region #fontFamily-generic 6.4.1 Usage Scenario
  • 6.4.2 Constraints 6.5 5.5 Use of Constrained TTML Feature fontFamily-generic 6.5.1 #fontSize Usage Scenario 6.5.2 Constraints
  • 6.6 5.6 Use of Constrained TTML Feature fontSize #styling-* 6.6.1 Usage Scenario
• 6.6.2 6. Layout Constraints
  • 6.7 6.1 Use of Constrained TTML Feature fontStyle-italic 6.7.1 #layout Usage Scenario 6.7.2 Constraints
• 6.8 Use of Constrained TTML Feature length-percentage 6.8.1 Usage Scenario 6.8.2 7. Timing Constraints
  • 6.9 7.1 Use of Constrained TTML Feature length-positive #timing 6.9.1 Usage Scenario
  • 6.9.2 Constraints 6.10 7.2 Use of Constrained TTML Feature styling-* 6.10.1 #animation Usage Scenario 6.10.2 Constraints
• 6.11 Use of Constrained TTML Feature styling-inheritance-content 8. Other Constraints
  • 6.11.1 Usage Scenario 6.11.2 8.1 Encoding Constraints
  • 6.12 8.2 Use Ease of Constrained TTML Feature styling-inheritance-region Use Constraints 6.12.1 Usage Scenario 6.12.2 Constraints
• 6.13 9. Use of Constrained Features in TTML Feature textAlign-absolute 6.13.1 Usage Scenario 1.0 Used in This Profile
• 6.13.2 10. Constraints Error handling
• 6.14 A. Use of Constrained Future Needs for TTML Feature textDecoration-under next for Simple Delivery
  • 6.14.1 Usage Scenario 6.14.2 A.1 Constraints Values for font family support 6.15 Use of Constrained TTML Feature textOutline-unblurred
  • 6.15.1 A.2 Usage Scenario Support for character edge features
  • 6.15.2 A.3 Constraints Specify rendering model that accounts for drawing performance
• 6.16 B. Use Mapping of US Government Requirements to Constrained TTML Feature writingMode-horizontal-lr 6.16.1 Usage Scenario Profile Features
• 6.16.2 C. Constraints Code points 7. Layout Constraints 7.1 Use of Constrained TTML Feature layout
• 7.1.1 D. Usage Scenario Color values
• 7.1.2 E. Constraints Acknowledgements
• 7.2 Use of Constrained TTML Feature lineBreak-uax14 F. References
  • 7.2.1 F.1 Usage Scenario Normative references
  • 7.2.2 F.2 Constraints Informative references

8.1 1. Use of Constrained Introduction

TTML Feature timing 8.1.1 Usage Scenario 1.0 [ 8.1.2 Constraints TTML10 8.2 Use ] provides many features to satisfy captioning and subtitling requirements, not all of Constrained TTML Feature time-offset-* 8.2.1 Usage Scenario 8.2.2 Constraints 8.3 Use which are intended for end user display. Requirements have been identified by key video and content communities to define an interoperable delivery profile using the core features specifically designed for online presentation of TTML. Such a profile allows the community of Constrained TTML Feature frameRate and frameRateMultiplier 8.3.1 Usage Scenario 8.3.2 Constraints 8.4 Use users to construct constrained presentation engines for TTML. This document defines the behavior expected of Constrained a TTML Feature animation content player using the presentation processor constraints for such an online delivery profile.

The Simple Online Delivery profile is focused on streamlined delivery of closed captions on the Internet. This interoperability profile supports core TTML features to deliver content originating legacy formats such as [ 11. Error handling CEA608 ] and [ CEA708 A. Future Needs for TTML next ] content, and is targeted primarily for delivery in US markets.

The Simple Delivery A.1 Values Profile for fontFamily support Closed Captions focuses interoperability using [ B. Mapping of US Government Requirements to Constrained Profile Features TTML10 ] to support delivery of closed captions for video content. Other profiles based on [ C. Code points TTML10 ] may target other types of subtitles such as on-screen text or graphics. This interoperability profile is a proper subset of [ C.1 Color values TTML10 ] intended to support features required for US Government closed captioning requirements for online presentation.

C.2 2. Acknowledgements Terms, Definitions, and Conventions

The terms and definitions in [ D. References TTML10 ] serve as the basis for this interoperability profile. Terms found here are in addition to those found in [ D.1 Normative references TTML10 ].

When this document refers to a TTML element type, if no namespace prefix is specified, then the tt namespace prefix is implied. This prefix and other explicit namespace prefixes used herein correspond to those TTML namespaces defined in [ D.2 Informative references TTML10 ] Section 5.1.

1. 3. Conformance

As well as sections marked as non-normative, all authoring guidelines, diagrams, examples, and notes in this specification are non-normative. Everything else in this specification is normative.

The key words must , must not , required , should , should not , recommended , may , and optional in this specification are to be interpreted as described in [ RFC2119 ].

This profile identifies the content and player defines (1) constraints on documents and (2) minimum requirements for closed captioning using TTML. To conform to this profile, a TTML presentation engine must : processor capable of presenting such constrained documents.

A document conforms to this profile if it:

1. Satisfy the requirements specified contains all elements and attributes required by Section 3.2.1 Generic Processor Conformance [TTML] this profile;
2. does not contain or employ elements and attributes that are required to implement: The mandatory TTML 1.0 features referenced in Table E-3, Section D.2 Feature Support prohibited by this profile; and
3. Supports the semantics satisfies all other semantic constraints defined for those features in the context of by this profile. Satisfy all requirements specified in Sections 4-8 and

A conformant document is said to be strictly conformant if it does not contain any references from those sections feature that is not explicitly specified as included in this document. profile.

This constrained profile enumerates a set of required A TTML features, some of which may be constrained in behavior, and presentation processor conforms to this profile if it:

1. implements support for the capabilities required of a Presentation Processor profile definition specified in Features in TTML 1.0. 1.0 Used in This Profile ; and
2. implements support for all other semantics explicitly defined by this profile.

The semantics defined in TTML 1.0 [ TTML10 ] apply unless otherwise constrained in this profile.

Claims of document conformance must make use this URI and implement the required features and constraints of use and processing outlined in this profile. the following profile URI, identified with the indicated profile name:

Conformance to this profile does not preclude the preclude:

1. use of other features defined in TTML 1.0 but [ TTML10 ], in which case such behavior is not defined here. 2. Terms and Definitions The terms and definitions in TTML 1.0 serve as the basis for this interoperability profile. Terms found here are in addition to those found in TTML 1.0. Name Definition Required feature A TTML feature is required for use. Required feature with constraints A TTML feature is required but constrained by this profile for here; or
2. use and/or processing. Optional feature Any TTML feature not included of other profiles that may implement the features in this profile.

6. 5. Style Constraints

<region id="r1" tts:backgroundColor="#00000000"/>
...
<p region="r1" tts:backgroundColor="#1049edff">
  Twinkle, twinkle, little bat!<br>
  How <span tts:backgroundColor="#ed1078ff">I wonder</span> where you're at!

</

p
and
span
elements
to
allow
for
semi-transparent
and
transparent
opacities.



>

<tt xml:lang="en-us" xmlns="http://www.w3.org/ns/ttml" 
    xmlns:s='http://www.w3.org/ns/ttml#styling' 
    xmlns:p='http://www.w3.org/ns/ttml#parameter' >
  <head>
    <p:profile use="http://www.w3.org/ns/ttml/profile/simple-delivery"/>
    <styling>
      <!-- A typical transparent region with centered text that has an outline -->
      <style xml:id="bottomMidStyle" s:textAlign="center" s:textOutline="#000000ff 5%" s:backgroundColor="#00000000" 
             s:color="#ffffffff" s:origin='20% 58%' s:extent='60% 18%'/>
    </styling>
    <layout>
      <!-- typical 'Pop-up' type region -->
      <region xml:id="bottomMid" style="bottomMidStyle" />
    </layout>
  </head>
  <body>
    <div style="defaultFont">
      <p region="bottomMid" begin='00:00:00.101' end='00:00:03.000'> This is a Pop-up caption. </p>
    </div>
  </body>

</


tt


>

<style xml:id="bottomMidStyle" s:textAlign="center" s:textOutline="black 1px" s:backgroundColor="transparent" 
       s:color="#ffffffff" s:origin='20% 58%' s:extent='60% 18%'/>
<style xml:id="topMidStyle" s:textAlign="center" s:textOutline="black 1px" s:backgroundColor="transparent" 

s:color


=

"

white

#ffffffff


"



s:origin


=

'

20%
10%

'



s:extent


=

'

60%
18%

'

/>

<?xml version="1.0" encoding="utf-8"?>
<tt xml:lang="en-us" xmlns="http://www.w3.org/ns/ttml" xmlns:s='http://www.w3.org/ns/ttml#styling'>
  <head>
    <styling>
      <style xml:id="s1" s:display="none" s:extent='40% 18%'/>
    </styling>
    <layout>
      <region xml:id="r1" style="s1">
        <set begin='00:00:10.000' end='00:00:10.330' s:display='auto'/>
        <set begin='00:00:10.000' end='00:00:10.330' s:origin='10% 10%'/>
        <set begin='00:00:11.670' end='00:00:12.000' s:display='auto'/>
        <set begin='00:00:11.670' end='00:00:12.000' s:origin='10% 10%'/>
      </region>
      <region xml:id="r2" style="s2">
        <set begin='00:00:10.330' end='00:00:10.670' s:display='auto'/>
        <set begin='00:00:10.330' end='00:00:10.670' s:origin='50% 10%'/>
        <set begin='00:00:11.670' end='00:00:12.000' s:display='auto'/>
        <set begin='00:00:11.670' end='00:00:12.000' s:origin='50% 10%'/>
      </region>
      <region xml:id="r3" style="s3">
        <set begin='00:00:10.670' end='00:00:11.000' s:display='auto'/>
        <set begin='00:00:10.670' end='00:00:11.000' s:origin='10% 78%'/>
        <set begin='00:00:11.670' end='00:00:12.000' s:display='auto'/>
        <set begin='00:00:11.670' end='00:00:12.000' s:origin='10% 78%'/>
      </region>
      <region xml:id="r4" style="s4">
        <set begin='00:00:11.000' end='00:00:11.330' s:display='auto'/>
        <set begin='00:00:11.000' end='00:00:11.330' s:origin='50% 78%'/>
        <set begin='00:00:11.670' end='00:00:12.000' s:display='auto'/>
        <set begin='00:00:11.670' end='00:00:12.000' s:origin='50% 78%'/>
      </region>
    </layout>
  </head>
  <body>
    <div>
      <!--four speakers count off, and then all call 'Jump' together -->
      <p begin='00:00:10.000' end='00:00:10.330' region="r1" >One</p>
      <p begin='00:00:10.330' end='00:00:10.670' region="r2" >Two</p>
      <p begin='00:00:10.670' end='00:00:11.000' region="r3">Three</p>
      <p begin='00:00:11.000' end='00:00:11.330' region="r4" >Four</p>
      <p begin='00:00:11.670' end='00:00:12.000' region="r1" >Jump!</p>
      <p begin='00:00:11.670' end='00:00:12.000' region="r2" >Jump!</p>
      <p begin='00:00:11.670' end='00:00:12.000' region="r3">Jump!</p>
      <p begin='00:00:11.670' end='00:00:12.000' region="r4" >Jump!</p>
    </div>
  </body>

</


tt


>

6.12.2 6. Layout Constraints None 6.13 Use of Constrained TTML Feature textAlign-absolute

<


p


>

I
always
get
the
fuzzy
end

<


br


/>

of
the
lollipop

</


p


>

8. 7. Timing Constraints

<


p




begin


=

'

00:00:01.000

'



end


=

'

00:00:11.123

'



region


=

"

r1

"

>

Test

</


p


>

<tt ttp:frameRate='30' ttp:frameRateMultiplier='1000 1001' ...>
...


<


p




begin


=

'

00:00:01:00

'



end


=

'

00:00:11:22

'



region


=

"

r1

"

>

Test

</


p


>

8.4.1 8. Usage Scenario TTML Feature Usage type Context of Usage Scope Constraint #animation Required with constraints       Other Constraints

10. 9. Features in TTML 1.0 Used in This Profile

<?xml version="1.0" encoding="utf-8"?>
<profile xmlns="http://www.w3.org/ns/ttml#parameter">
  <features xml:base="http://www.w3.org/ns/ttml/feature/">
    <!-- required (mandatory) feature support -->
    <feature value="required">#animation</feature>
    <feature value="required">#backgroundColor-block</feature>
    <feature value="required">#backgroundColor-inline</feature>
    <feature value="required">#color</feature>
    <feature value="required">#content</feature>
    <feature value="required">#core</feature>
    <feature value="required">#display-region</feature>
    <feature value="required">#displayAlign</feature>
    <feature value="required">#fontFamily-generic</feature>
    <feature value="required">#fontSize</feature>
    <feature value="required">#fontStyle-italic</feature>
    <feature value="required">#frameRate</feature>
    <feature value="required">#frameRateMultiplier</feature>
    <feature value="required">#layout</feature>
    <feature value="required">#length-percentage</feature>
    <feature value="required">#length-positive</feature>
    <feature value="required">#lineBreak-uax14</feature>
    <feature value="required">#presentation</feature>
    <feature value="required">#profile</feature>
    <feature value="required">#structure</feature>
    <feature value="required">#styling</feature>
    <feature value="required">#styling-inheritance-content</feature>
    <feature value="required">#styling-inheritance-region</feature>
    <feature value="required">#styling-inline</feature>
    <feature value="required">#styling-referential</feature>
    <feature value="required">#textAlign-absolute</feature>
    <feature value="required">#textDecoration-under</feature>
    <feature value="required">#textOutline-unblurred</feature>
    <feature value="required">#time-offset</feature>
    <feature value="required">#timing</feature>
    <feature value="required">#writingMode-horizontal-lr</feature>
  </features>
</profile>
 
 

11. 10. Error handling

A presentation process may be presented with documents that contain features that are not understood. The table that follows outlines semantics defined by [ TTML10 ] Section 6.1.1 apply with regard to the behavior expected under specific conditions. The pre-requisite presence of a reference to other standard or non-standard profiles. In particular, if the caption file an additional, non-standard profile is syntactically valid XML. specified for use by a document and is not dereferencable by the presentation processor, then the document must not be further processed without an explicit override from the end user.

The semantics defined by [ Feature Requirement Action Known Required TTML10 ] Section 6.1.3 apply if some standard or non-standard feature is required, the feature is present in the document, and the presentation processor does not support that feature. In this case also, the document must not interpret Unknown Required be further processed without an explicit override from the end user.

If a feature is present in a document and support for that feature is not required by the profile(s) referenced (or defined) by the document, and if the presentation processor does not support or otherwise recognize that feature, then the feature must ignore be ignored.