exporting to jpeg from 32-bit float linear image produces jpeg in linear color space
Submitted by Tomasz Goliński
When I open a photo (exported from Darktable with an embedded color profile but it is just plain sRGB), convert it to 32-bit float sRGB, and export to JPEG I get a file which appears in other applications too bright and flat. The file is indeed saved in linear color space ("linear TRC variant generated by GIMP") NB. thumbnail is OK).
While those kind of JPG files might be useful to somebody, I believe that at least there should be an export option to convert back to perceptual color space as these files are not widely supported. Moreover GIMP itself doesn't open them correctly - it sets precision to 8-bit perceptual. However magically, switching to linear doesn't convert the data, it just reinterpretes input correctly as linear and produces expected output.
The key component again is that the input image has its own profile (even though it is just sRGB). When I discard the profile, the problem disappears. The problem appeared sometime last year, I don't recall exactly, but if it would be helpful I can do bisect.
Version: git master