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Bug 602527 - silently flattens tRNS-specified alpha channel to 1-bit
silently flattens tRNS-specified alpha channel to 1-bit
Status: RESOLVED DUPLICATE of bug 86627
Product: GIMP
Classification: Other
Component: Plugins
2.6.7
Other Linux
: Normal normal
: ---
Assigned To: GIMP Bugs
GIMP Bugs
Depends on:
Blocks:
 
 
Reported: 2009-11-20 19:16 UTC by Ari Pollak
Modified: 2009-11-20 21:04 UTC
See Also:
GNOME target: ---
GNOME version: ---

Attachments
pal.png (1.11 KB, image/png)
2009-11-20 19:16 UTC, Ari Pollak 		Details
flat.png (867 bytes, image/png)
2009-11-20 19:16 UTC, Ari Pollak 		Details

Description Ari Pollak 2009-11-20 19:16:10 UTC 
Created attachment 148186 [details]
pal.png

From http://bugs.debian.org/557249:

Gimp silently flattens the alpha channel of PNG images whose
transparency information is specified by tRNS chunks to 1-bit.

The attached image, 'pal.png' (courtesy of Jason Summers,
http://entropymine.com/jason/testbed/pngtrans/), when opened in Gimp
and saved, is mangled to the attached 'flat.png'.
Comment 1 Ari Pollak 2009-11-20 19:16:27 UTC 
Created attachment 148187 [details]
flat.png
Comment 2 Sven Neumann 2009-11-20 19:52:05 UTC 
Yes, GIMP doesn't support full transparency on indexed images. I am pretty sure there is already a bug report about this.
Comment 3 Sven Neumann 2009-11-20 19:58:23 UTC 

*** This bug has been marked as a duplicate of bug 86627 ***