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Thread

2001.10.10 15:48 "associated/unassociated alpha images", by Sophia Nancy
2001.10.10 17:31 "Re: associated/unassociated alpha images", by Peter Montgomery

2001.10.10 17:31 "Re: associated/unassociated alpha images", by Peter Montgomery

Sophia,

Go to this FTP site:

ftp.sgi.com/graphics/tiff/

and get the file called "v3.4pics.tar.gz" or "v3.4pics.tar.Z". Included in the collection of images is one with an "associated" alpha channel.

Thanks,
PeterM

PS - PhotoShop is so unbelievably stupid and inept of its handling of the alpha channel it's not even funny. If you want to make your own, download the GIMP. If you scribble with a brush in a window and then save it as a TIFF, you'll get a proper RGBA image with pre-multiplied alpha (e.g. what the TIFF spec calls "associated"). Try the same in PhotoShop and you get your scribbles over a white background. PhotoShop is retarded when it comes to alpha handling.