Photo as a wallpaper has changed colours
I have the following problem: I set a photo as a wallpaper for my desktop, but the colours are noticeable different (more blue) from the original (i.e. seen in the default Ubuntu image viewer or Firefox).
The difference can be captured by a screenshot:
Picture
Same Picture as wallpaper
This is puzzling. I have Ubuntu 16.04.2 (Xenial LTS) on HP's EliteBook 2540p. I didn't change anything with default drivers etc.
11 Answer
Your image contains a colour profile that Firefox and Eye of Gnome (Ubuntu's default image viewer) appear to ignore. You can convert the image to a "default" colour profile with many image editors.
One that can do it is GIMP. When you open an image with a colour profile GIMP will ask you if you want to convert it to the default colour profile. Export the image to a new file, set the latter as your wallpaper and you should be good to go. This will leave you with the lower variant of the image in your question. The main difference appears to be colour saturation which you can adjust to your liking via GIMP's Colour menu.
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