https://bugs.kde.org/show_bug.cgi?id=441162
--- Comment #8 from Ancoron <ancoron.lucife...@gmail.com> --- The actual issue here is that gwenview (or Qt) interprets the gamma value incorrectly. ImageMagick (and other tools) set a default gamma of 2.2 for PNG's and/or other file formats that support this metadata. For the attached files, here's some metadata: test.png: Bit Depth : 8 Color Type : RGB with Alpha Compression : Deflate/Inflate Filter : Adaptive Interlace : Noninterlaced Pixels Per Unit X : 11811 Pixels Per Unit Y : 11811 Pixel Units : meters Image Size : 1800x2700 hires.png: Bit Depth : 8 Color Type : RGB Compression : Deflate/Inflate Filter : Adaptive Interlace : Noninterlaced Gamma : 2.2 <<< creating trouble for gwenview White Point X : 0.3127 White Point Y : 0.329 Red X : 0.64 Red Y : 0.33 Green X : 0.3 Green Y : 0.6 Blue X : 0.15 Blue Y : 0.06 Background Color : 255 255 255 Pixels Per Unit X : 11811 Pixels Per Unit Y : 11811 Pixel Units : meters Modify Date : 2021:08:19 10:24:04 Warning : [minor] Text chunk(s) found after PNG IDAT (may be ignored by some readers) Datecreate : 2021-08-19T10:23:53+00:00 Datemodify : 2021-08-19T08:57:54+00:00 Image Size : 1800x2700 You can "fix" the PNG's for gwenview usually with: `convert <input> -set gamma 2.2 <output>` ...which actually sets the PNG gamma value to 0.4545, since it's the inverse (and which is what gwenview should be doing). However, that breaks the image for almost any other viewer/browser/editor that interpret the gamma value, since they then are doing the color correction in the inverse way with the inversed value. Some background on why it is the way it is: https://www.cambridgeincolour.com/tutorials/gamma-correction.htm -- You are receiving this mail because: You are watching all bug changes.
