[CREATE] Lens correction database

[Pablo d'Angelo]

Hi Andrew,

Andrew Zabolotny wrote:
> From Thu, 10 Jan 2008 14:01:35 +0100
> Pablo dAngelo <Pablo.dAngelo at web.de> wrote:

>> The Zhang algorithm, for example as implemented in Bouguet's 
>> matlab toolbox or the CamChecker program are suitable for this,
>> and will likely provide higher quality estimates as a 360°deg
>> panorama.
> Zhang distortion model seems pretty simplistic to me... as far as I
> understand it was targeted at webcams (e.g. pinhole lenses). I
> haven't even included it in lensfun so far, but it's easy to add
> it as soon as somebody needs it.

The model is not as detailed as others, but his algorithm to estimate
it from planar targets (chessboards) is quite good and can be used for
more elaborate models (such as the one used in Bouguets camera calibration 
toolbox (with tangential distortions)), too.

 > Besides, it does not evaluate chromatic
> aberrations and vignetting. Calibrating TCA should give a good
> increase in image sharpness towards the edges... and this would be
> pretty neat for panoramas, especially if you don't overlap the images
> too much.

Yes, most models only consider one effect, but they can be easily combined.

>> Btw. how is progress on the ufraw integration?
> I've finished the draft UI and now I'm implementing a system where
> arbitrary filters can be inserted into the de-bayering chain. I'd say,
> 50% complete.

Sounds good. So we can correct TCA before debayering in the future?

ciao
   Pablo