0 Replies Latest reply on Apr 13, 2016 8:20 AM by BGVentuz

    Premultiplied Alpha: Using zero Alpha to implement additive color

    BGVentuz

      Hi,

       

      Is it possible to tell PPro not to ignore pixels having color values and a zero alpha value when in premultiplied alpha mode?

       

      Premultiplied alpha as in these equations

      out_alpha = (1 - new_alpha) * old_alpha + new_alpha

      out_color = (1 - new_alpha) * old_color + new_color

      should result in an additive blending if new_alpha is zero.

      But in PPro nothing will be displayed.

       

      SDKFileInfo8->vidInfo.alphaType is set to alphaBlackMatte. Am I setting the wrong mode?

       

      Best Regards

      -Bjoern Gdanietz-