Re: [Boost-users] [gil] inverting alpha channel

Subject: Re: [Boost-users] [gil] inverting alpha channel
From: Christian Henning (chhenning_at_[hidden])
Date: 2011-03-07 10:53:43

Hi Alex,

> I have RGBA images using alpha=0 as opaque and alpha=255 as transparent. Is
> there any way that I can get png_write_view to use this convention without
> actually changing the data?

You could use a color_converted_view with your own rgba to rgb
converter. I think I posted some code for that on this list a couple
of months ago.

http://groups.google.com/group/boost-list/browse_thread/thread/260f77066a3a1929

Or you could use the new IO extension which was reviewed last
December. This extension can write rgba8 and rgba16. You can find the
source here:

http://code.google.com/p/gil-contributions/downloads/detail?name=boost_review.zip&can=2&q=

Regards,
Christian