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/260f77066a3a1... 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