W3C home > Mailing lists > Public > public-svg-wg@w3.org > July to September 2008

Unwanted restriction for JPEG images that have colour profiles.

From: Chris Lilley <chris@w3.org>
Date: Wed, 16 Jul 2008 14:41:34 +0200
Message-ID: <1538623714.20080716144134@w3.org>
To: public-svg-wg@w3.org

Hello ,

I just noticed a problem in Appendix H.
http://dev.w3.org/SVG/profiles/1.2T/publish/jpeg.html


  SVG Tiny 1.2 UA's should convert Y,Cb,Cr values compressed in the
  JPEG image to RGB as defined in the JFIF specification [JFIF] and
  may assume that the RGB values are sRGB.

While that usefully covers what colour space is meant by RGB, in the
absence of other information (since the JFIF specification is silent
on the matter) it should obviously not take precedence when
information *is* supplied (ie an ICC colour profile in the JPEG
image). The current wording seems to forbid this, which is not wanted.

For Tiny, colour management is optional but profiles that build on
Tiny may require it. I suggest therefore this modified wording; it
adds no new conformance criteria but makes the intention clearer:

  SVG Tiny 1.2 UA's should convert Y,Cb,Cr values compressed in the
  JPEG image to RGB as defined in the JFIF specification [JFIF] and
  may assume, in the absence of a colour profile, that the RGB values
  are sRGB.

-- 
 Chris Lilley                    mailto:chris@w3.org
 Interaction Domain Leader
 W3C Graphics Activity Lead
 Co-Chair, W3C Hypertext CG
Received on Wednesday, 16 July 2008 14:48:16 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 21:20:09 UTC