I’m not familiar with dark channel and wavelets and such, so googled earlier and found this paper from 2009
https://www.robots.ox.ac.uk/~vgg/rg/papers/hazeremoval.pdf
Perhaps some of you know of it, perhaps it is what’s in RT. I recommend it, there are comparison photos with other de-haze methods (and lots of maths). I found it interesting, didn’t realise you could “cut through the noise” like that. Perhaps naïve - I suppose the spy satellites have been doing it for ages?.. I’m still so impressed with how much is in RT (though need to sort out a better system, my 32bit Win7 easily crashes).
[quote=“RawConvert, post:21, topic:733”]
I suppose the spy satellites have been doing it for ages?..
[/quote]I have not worked on spy satelites (and if I did I probably couldn’t say so). But in general the ‘dehazing’ applied to satellite photos is more simple because the distance of the imaged points is practically very similar so you can get away with subtracting a uniform (or at least low frequency) value.
I explored dehazing algorithms a bit in the past and it looks like a nice problem to work on. I’d love to explore it once I find time for it.
For now the best solutions I found with existing FOSS software was with darktables equalizer (similar to the wavelets in rawtherapee) and some selective color adjustments. You can find this described here: Dehaze equivalent in darktable or RawTherapee - #13 by Jonas_Wagner I’m fairly sure the equalizer part can also be done in rawtherapee via wavelets (minus the masking). I’m not sure about the local color adjustments.
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