Am 22.02.2015 um 20:53 schrieb KOVÁCS István:
> Thanks all!
> Even with highlight recovery disabled, we lose much of the details.
> Perhaps a programmatic way of doing something similar to what I did
> (computing some kind of (weighted) average of the original R-G-B-R
> photosite values and applying that to add fake luminance on top of
> 'average colour' surrounding the area) could work.
> Note that an exposure correction of -1EV combined with 'reconstruct
> color' brings out reasonable detail, though the previously blown-out
> part is still *much* brighter than anything around it.

Maybe you can have a look at PR 866 and see if the added white point 
adjustment parameter can do what you need.

I have more concerns with our ability to reconstruct color information. 
We use an impainting algorithm which works quite well on skin tones but 
is not as good as RT color propagation. We could either port the RT 
algorithm or find something different ourselves.

One idea: if we can identify overexposed highlights later in the 
pixelpipe (e.g. by L > 100) we could do the following. A good source for 
the right color would be non-overexposed pixels which are spatially 
close-by and which have a similar L value (we might need to combine this 
with some kind of white point adjustment for the highlights). Getting 
the right color estimationg could be a task for some kind of bilateral 
filter.

>
> Now, any idea about the behaviour of the colour picker (being
> unaffected by the highlight recovery method, and also displaying lower
> L value for the visually brighter spot)?

That's not a problem of the color picker. If you look at modules in the 
Lab color space: they have the same paradoxical effect in the L value 
(you can inspect those values with the color picker in parametric 
masks). I assume that this is one of the many not-so-obvious 
characteristics of the Lab color space.

Ulrich

>
> Thanks,
> Kofa
>

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