Broken alpha handling in images#545

Merged

mdboom merged 2 commits intomatplotlib:v1.1.xfrom

mdboom:alpha_image_resize_bug

Oct 28, 2011

Commits on Oct 24, 2011

Make "set_alpha()" work on images. Now, alpha blending is handled in the backends. Tested and works on Agg, Pdf and Svg. (Ps does not support alpha).
mdboom
committed
Tell Agg that we're giving it pre-multiplied image data
mdboom
committed