210917 Philip Webb wrote: > It's only when I crop a PNG image in Gwenview > & save it in place (ie with the same name), that the colors are faded > & that's only when viewed with Gwenview, not eg with Feh. > The bad case does look like a Gwenview bug, > & in fact, as I had forgotten (grimace), I did submit a bug previously : > KDE Bug 420357 back in April 2020, to which no-one has yet responded. > I've added a comment & we'll see if there's any response this time.
Tibor Nagy of KDE Bugzilla has replied very promptly : My guess this happens due to botched gamma handling. Washed out images are a prime symptom of that kind of bugs. Seems like when a PNG gAMA chunk is present, Gwenview applies the gamma transform in the opposite direction it should, thus the washed out images. Seems to be Qt bug, already fixed in 5.15.x : https://github.com/qt/qtbase/commit/de2c3ccd49cb89e0c6912da3b03705a36ef03946 As you can see from the link above, some coder forgot to invert a value, using 'gamma' when it sb '1/gamma'. The patch is dated 'June 11', so it make take awhile yet to reach Gentoo. Meanwhile, I have 2 workarounds which are in fact improvements for me. I have amended the Imagemagick 'import' command I use for screenshots to produce them as JPGs, which cb safely cropped already via Gwenview. Alternatively, Firefox will make screenshots via R-click on its window & the area to be grabbed cb marked on the screen, so already cropped. >From the beginning, I thought it was a programming bug, as it appeared suddenly after a KDE update in spring 2020. -- ========================,,============================================ SUPPORT ___________//___, Philip Webb ELECTRIC /] [] [] [] [] []| Cities Centre, University of Toronto TRANSIT `-O----------O---' purslowatchassdotutorontodotca
