<p>Premultiplied alpha is a widely accepted best practice for graphics rendering, offering many benefits over 'straight' interpolative alpha (most importantly, it works correctly with bilinear filtering, and because the blend function is associative, intermediate results can be cached in rendertargets without changing the end result).</p>
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<p>Yet most paint programs and image file formats do not use premultiplied alpha.</p>
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<p>It would be useful if DirectXTex included a conversion function to transform an image into premultiplied format, and texconv exposed a commandline switch to apply this.</p>
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<p>This feature would also improve support for DirectXTK SpriteBatch and BasicEffect, which use premultiplied alpha by default (although they can optionally be configured otherwise).</p>
Comments: ** Comment from web user: walbourn **
<p> </p>
<p>Yet most paint programs and image file formats do not use premultiplied alpha.</p>
<p> </p>
<p>It would be useful if DirectXTex included a conversion function to transform an image into premultiplied format, and texconv exposed a commandline switch to apply this.</p>
<p> </p>
<p>This feature would also improve support for DirectXTK SpriteBatch and BasicEffect, which use premultiplied alpha by default (although they can optionally be configured otherwise).</p>
Comments: ** Comment from web user: walbourn **
http://en.wikipedia.org/wiki/Alpha_compositing
http://blogs.msdn.com/b/shawnhar/archive/2009/11/06/premultiplied-alpha.aspx
http://home.comcast.net/~tom_forsyth/blog.wiki.html#%5B%5BPremultiplied%20alpha%5D%5D