PNG image resizing bug

[rom92]

Here is the original image:
​http://dl.rom1v.com/images/debian-installer.png

If I upload it to a Wordpress blog, it resizes it to 300×300, and the resulting image is OK.

If instead, I upload this image:
​http://dl.rom1v.com/images/debian-installer-optipng.png
(which is the original image optimized by optipng)
then the resulting 300×300 image has bad colors.

With other images optimized by optipng, I have not this problem in Wordpress, maybe a specific bug when there are only few colors (maybe the bug always happens, but it more visible when few colors)…

[scribu]

Yep, it's a problem with the GD Image library.

Closing as duplicate of #6821