[poppler] [RFC] Add option to keep alpha channel to Qt frontends

[Albert Astals Cid]

El Dissabte, 4 de juliol de 2015, a les 00:28:13, Adam Reichold va escriure:
> Hello again,
> 
> Am 03.07.2015 um 20:32 schrieb Albert Astals Cid:
> >> Not doing the alpha blending (but exporting the alpha channel) is still
> >> faster, i.e. also slightly above two percent in the same benchmarks.
> >> (Meaning XBGR8 with paper colour is 2.2 % slower than RGB8 with paper
> >> colour which itself is 2.2 % slower than XBGR8 without paper colour.)
> > 
> > What about BGR8 without paper colour?
> 
> I am not sure this is useful because what would you do with an image
> without the alpha channel and without the background colour blended in?
> (You can do it of course, but it does look horrible when for example
> painting this on top of the paper colour using QPainter.)

Rendering with RGB8 still gives you the alpha channel in the alpha channel of 
SplashImage, no?

But i guess feeding that to QImage won't be nice since it basically means 
reconstructing a XRGB8 buffer with the RGB8 buffer and the alpha channel, is 
that right?

Cheers,
  Albert

> 
> Best regards, Adam.