ISSUE-432: Multiple layers of background color in HRM

Multiple layers of background color in HRM

Raised by:
Glenn Adams
Opened on:
Does the HRM capture the composited painting requirements for the multiple layers of background colors? i.e., region, body, div, p, and span can all have distinct background colors that must be composited. I ask this because 9.2 steps 2 and 3 seem to imply only two potential background color layers, and not 5 layers as is permitted. The reason they may need to be composited is because each of these 5 layers may specify an alpha component in their color specification. In addition, tts:opacity applies to a region's content as a whole, and tts:color for text foreground can also specify alpha. Overall, that yields 7 possible compositing steps to a presentation buffer (in text profile).
Related Actions Items:
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Related emails:
  1. {minutes} TTWG Meeting 2015-10-15 (from on 2015-10-15)
  2. {agenda} TTWG Meeting 2015-10-15 (from on 2015-10-14)
  3. RE: {agenda} TTWG Meeting 2015-10-08 (from on 2015-10-08)
  4. {agenda} TTWG Meeting 2015-10-08 (from on 2015-10-07)
  5. {agenda} TTWG Meeting 2015-10-01 (from on 2015-10-01)
  6. {agenda} TTWG Meeting 2015-09-24 (from on 2015-09-23)
  7. Update re: outstanding IMSC1 issues (from on 2015-09-21)
  8. ISSUE-432: Multiple layers of background color in HRM [TTML IMSC 1.0] (from on 2015-09-21)

Related notes:

Yes. NBG(Ri) is defined as the total number of tts:backgroundColor attributes associated with a given region.

Perhaps it needs to be clarified?

Pierre-Anthony Lemieux, 21 Sep 2015, 20:46:21

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