Removed DPI rounding from BMP, JPEG and PNG loading #5476
Merged
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Helps #4129
BMP and PNG don't save our
dpi
value untransformed. Instead, BMP multiplies it by 39.3701 and PNG divides it by 0.0254, and then saves it as an integer. Because this limits the precision, that makes it unlikely thatdpi
value used to save an image will be the samedpi
that is loaded afterwards - this means that this PR abandons the idea that you should be able to roundtrip DPI values. SoAfter that, it removes rounding from JPEG loading as well. This is more of a cleanup than a change though, because as it is an integer when saving, I don't think it is possible to have a JPEG with a float dpi without hexediting the image.