-Title: Extensions to the PNG Third Edition Specification, Version 1.6.0
+Title: Extensions to the PNG Third Edition Specification, Version 1.6.1
Shortname: pngext
Level: none
-Status: NOTE-FPWD
+Status: NOTE-WD
Group: PNGWG
-URL: https://w3c.github.io/PNG-spec/extensions/Overview.html
+URL: https://w3c.github.io/png/extensions/Overview.html
TR: https://w3.org/TR/png-extensions/
Editor: Chris Lilley, W3C, https://svgees.us/, w3cid 1438
Former Editor: Glenn Randers-Pehrson
@@ -29,15 +29,21 @@ Local Boilerplate: copyright yes
"dSIG-spec": {
"href": "http://ftp-osl.osuosl.org/pub/libpng/documents/signatures/PNG_Digital_Signatures.spec.pdf",
"title": "PNG Digital Signatures: Extension Specification",
- "authors": "Thomas Kopp",
+ "authors": ["Thomas Kopp"],
"date": "17 Nov 2008"
},
"dSIG-example": {
"href": "http://ftp-osl.osuosl.org/pub/libpng/documents/signatures/PNG_Digital_Signatures.sample.html",
"title": "PNG Digital Signatures: Commented Example",
- "authors": "Martin Boßlet, Thomas Kopp",
+ "authors": ["Martin Boßlet", "Thomas Kopp"],
"date": "18 May 2008"
- }
+ },
+ "iDOT-description": {
+ "href": "https://www.hackerfactor.com/blog/index.php?/archives/895-Connecting-the-iDOTs.html",
+ "title": "Connecting the iDOTs",
+ "authors": ["Dr. Neal Krawetz"],
+ "date": "8 September 2020"
+ }
}
@@ -771,6 +777,20 @@ The pCAL chunk contains:
In the future, chunks will be fully specified
before they are registered.
+
+ iDOT Apple Multithreaded Decoding
+
+
+ The iDOT chunk enables multi-core machines
+ to use (at least) two cores to decode the PNG datastream.
+
+ It was developed by Apple, around 2011, but never registered.
+ It is commonly found in PNG images generated on Apple hardware.
+
+ This chunk has been reverse-engineered, and is described in detail
+ in a separate document, [[!iDOT-description]].
+
+
Text Chunk Keywords
@@ -803,7 +823,7 @@ The pCAL chunk contains:
This restricted set
- is the ISO-646 "invariant" character set [[!ISO 646]].
+ is the ISO-646 "invariant" character set [[!ISO646]].
These characters have the same numeric codes
in all ISO character sets,
including all national variants of ASCII.
@@ -1167,7 +1187,7 @@ What are x0 and x1 for?
not already listed in the PNG specification
are presented in alphabetical order:
-