From 3a79dd1f5e65ed7ed3e2e8a598fc1479eb2fcd9c Mon Sep 17 00:00:00 2001 From: Nigel Megitt Date: Fri, 20 Dec 2024 16:47:12 +0000 Subject: [PATCH] Open Add daptm:descType feature and permit user-defined values Closes #271 * Make `daptm:descType` a defined term * Permit user-defined values for `daptm:descType` as long as they are prefixed with `x-` * Require that no key in the registry table begins with `x-` * Add the TTML Metadata prefix `ttm:` to the Namespaces table * Sort the TTML namespaces to have the same order as in the TTML2 specificaiton * Define the `#descType` extension feature, and mark its disposition as Permitted. --- index.html | 46 ++++++++++++++++++++++++----- profiles/dapt-content-profile.xml | 1 + profiles/dapt-processor-profile.xml | 1 + 3 files changed, 40 insertions(+), 8 deletions(-) diff --git a/index.html b/index.html index 82bf813..25b253b 100755 --- a/index.html +++ b/index.html @@ -1627,13 +1627,15 @@

Script Event Description

Each Description Type is represented in a DAPT Document by a daptm:descType attribute on the <ttm:desc> element.

The <ttm:desc> element MAY have zero or one daptm:descType attributes. - The daptm:descType attribute is defined below.

+ The daptm:descType attribute is defined below.

 daptm:descType : string
-

Its permitted values are listed in the following registry table:

+

The permitted values for daptm:descType are either + those listed in the following registry table, + or can be user-defined:

Registry table for the daptm:descType attribute @@ -1666,6 +1668,7 @@

Script Event Description

+

Valid user-defined values MUST begin with x-.

@@ -2138,6 +2141,7 @@ 
Namespaces

               http://www.w3.org/XML/1998/namespace
               [[xml-names]]
             
+            
             
               TT
               tt
@@ -2150,18 +2154,24 @@ 
Namespaces

               http://www.w3.org/ns/ttml#parameter
               [[TTML2]]
             
-            
-              TT Feature
-              none
-              http://www.w3.org/ns/ttml/feature/
-              [[TTML2]]
-            
             
               TT Audio Style
               tta
               http://www.w3.org/ns/ttml#audio
               [[TTML2]]
             
+            
+              TT Metadata
+              ttm
+              http://www.w3.org/ns/ttml#metadata
+              [[TTML2]]
+            
+            
+              TT Feature
+              none
+              http://www.w3.org/ns/ttml/feature/
+              [[TTML2]]
+            
             
               DAPT Metadata
               daptm
@@ -3606,6 +3616,13 @@ 
Disposition of Features and Extensions

               This is the profile expression of .
             
           
+          
+            #descType
+            permitted
+            
+              This is the profile expression of daptm:descType.
+            
+          
           
             #onScreen
             permitted
@@ -3796,6 +3813,18 @@ 
#daptOriginTimecode

         
No presentation processor behaviour is defined for the #daptOriginTimecode extension.

       
 
+      

+        
#descType

+        
A transformation processor supports the #descType extension if
+          it recognizes and is capable of transforming values of the
+          daptm:descType attribute
+          on the <ttm:desc> element.

+  
+        
A presentation processor supports the #descType extension if
+          it implements presentation semantic support of the
+          daptm:descType attribute on the <ttm:desc> element.

+      

+
       

         
#onScreen

         
A transformation processor supports the #onScreen extension if
@@ -4162,6 +4191,7 @@ 
daptm:descType registry table definition

         
The key is the "daptm:descType" field.
         The "description" field describes the intended purpose of each value.
 
         
The registry entries for this registry table are located in .

+        
The key values for this registry table MUST NOT begin with x- which is reserved for user extensions.

       

 
       

diff --git a/profiles/dapt-content-profile.xml b/profiles/dapt-content-profile.xml
index 10f16ae..b69633b 100644
--- a/profiles/dapt-content-profile.xml
+++ b/profiles/dapt-content-profile.xml
@@ -93,6 +93,7 @@
     
     #agent
     #daptOriginTimecode
+    #descType
     #onScreen
     #scriptEventGrouping
     #scriptEventMapping
diff --git a/profiles/dapt-processor-profile.xml b/profiles/dapt-processor-profile.xml
index 0729164..93f091f 100644
--- a/profiles/dapt-processor-profile.xml
+++ b/profiles/dapt-processor-profile.xml
@@ -85,6 +85,7 @@
     #agent
     #contentProfiles-root
     #daptOriginTimecode
+    #descType
     #onScreen
     #represents
     #scriptEventGrouping