XPS 0.95 Superluminous Colors

We have clarified how consumers that do not understand superluminous colors should behave when encountering them in section 11.4.1 of the XPS specification v0.95. The text is as follows:

Consumers MAY handle superluminous colors or MAY instead choose to convert pre-multiplied source data containing superluminous colors to non-pre-multiplied data before composition by ignoring the superluminous portion of each color channel value [O11.10], as described in the following steps:

For each superluminous pixel with A < R or A < G or A < B


   If A = 0


      R* = 1

      G* = 1

      B* = 1




      A* = A

      R* = min(R/A,1)

      G* = min(G/A,1)

      B* = min(B/A,1)



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