Please, how works the fade correction?

[ilgk48]

Good afternoon,
please can someone tell me how PSP manages the fade correction? More precisely: which algorithms are applied?

Thanks to all.
Paolo

[ilgk48]

Sorry for my insistence in recalling this my old post: I'll try to be more specific.
Please:
in Adjust->Color->Fade Correction
can someone explain to me the "mathematical" use of the coefficent "Amount of Correction" ?

Is it a percentual augment applied to each channel RGB?
Does it refer to a correction applied in HSV or HSL space?
Other?

Thank you.
Paolo

[LeviFiction]

I'm sorry but I doubt anyone here will know how Corel (originally Jasc) does their math. Have you tried searching for patents to see if they made one for the technology?

It could be as simple as applying pre-defined curves and then progressively blending the maximum curve against the original image. It could be a lot more than that.

EDIT: I should note that the PSP manual suggests that if fade correction command isn't working well enough to try using their three automatic adjustments. Color Balance, Contrast, and Saturation. These three methods I believe do have parents you can look up.

[ilgk48]

Thank you LeviFiction,
I've searched and searched in Internet arguments like Color correction, fade correction, color balancing, white balancing.

In the past year I implemented, using VB.NET and parroting PSP, an application that treats images in a way specific to my goals and that now permits, to me, to put PSP aside: it is too heavy and cumbersome for my goals and so I do not need it anymore, if not for special uses.
My application Crops, Changes color, Fills with color, Creates masks, Finds contours; corrects colors using Max White, GreyWorld, White balancing and so on.
Only a curiosity remains to me and this is just the significance of "Amount of correction" .
It is in my hope to understand "Amount of correction" for enhancing my algorythms.



Have an happy new year.
Paolo