Preview.app and QuickLook displays 8-bit palette PNG with wrong gamma

Originator:pornelski
Number:rdar://15355456 Date Originated:
Status:Duplicate Resolved:
Product:Mac OS X Product Version:10.9.0
Classification: Reproducible:
 
PNG 8 (such as 256-color palette) images are significantly brighter and washed out in QuickLook preview and Preview.app's main window than in thumbnails in Preview.app's sidebar, Finder icons, Safari, Photoshop and other applications.

It appears as if gamma correction/color profile has been applied twice to the image (perhaps once to the palette and second time to remapped pixels?)

This is regression from Mountain Lion.

Steps to Reproduce:
Open http://i.imgur.com/KpGIQ7g.png in Preview.app or QuickLook
Compare with 24-bit version of the image: http://i.imgur.com/TWYciB0.png


Expected Results:
Both images are expected to look the same. Paletted PNG is expected to be displayed as sRGB gamma 2.2 image (http://i.imgur.com/KpGIQ7g.png) and look the same as 24-bit version (http://i.imgur.com/TWYciB0.png)

Actual Results:
Brightness of PNG8 images is clearly inconsistent: http://i.imgur.com/wRI04ij.jpg

Comments

Duplicate rdar://15303483

By pornelski at Nov. 2, 2013, 12:55 a.m. (reply...)

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