ISSUE-208: Define behavior for unsupported colors.

unsupported colors

Define behavior for unsupported colors.

Raised by:
Glenn Adams
Opened on:
tts:color (and other properties that use colors) don't define what a presentation processor should do if a specific color isn't supported; as such, this means that the default semantics of XSL-FO or CSS2 hold;

we should consider defining something specific or add a note that references the interpretation of unsupported colors in XSL-FO or CSS2 as appropriate
Related Actions Items:
No related actions
Related emails:
  1. No Meeting today 12-09-13 (from on 2013-09-12)
  2. Minutes for 05/09/13 (from on 2013-09-05)
  3. Agenda for 05/09/13 (from on 2013-09-04)
  4. RE: TTML Agenda for 29/08/13 (from on 2013-08-28)
  5. TTML Agenda for 29/08/13 (from on 2013-08-28)
  6. ISSUE-208 (unsupported colors): Define behavior for unsupported colors. [] (from on 2013-05-15)

Related notes:

I see the following language in 8.3.2:

"If a presentation processor does not support a specific, valid color or alpha value, then it must interpret it as being equal to the closest supported value."

This may be adequate to close this issue.

Glenn Adams, 15 May 2013, 23:59:23

Added further note in 8.3.5:

"In this context, the phrase closest supported value means the value for which the Euclidean distance between the computed color or alpha and the supported color or alpha in the RGB color space is minimized."

I believe this address this issue. See

Glenn Adams, 28 Aug 2013, 18:20:26

Display change log ATOM feed

David Singer <>, Nigel Megitt <>, Chairs, Thierry Michel <>, Philippe Le H├ęgaret <>, Atsushi Shimono <>, Staff Contacts
Tracker: documentation, (configuration for this group), originally developed by Dean Jackson, is developed and maintained by the Systems Team <>.
$Id: 208.html,v 1.1 2019/11/12 10:06:03 carcone Exp $