Preview image distorted when zoom to 33% or 50% using a lens correction profile in combination with 'Auto fill'

[Beep6581]

Originally reported on Google Code with ID 1807

When using a lens correction profile, the preview image at 50% zoom is broken. With
some Canon profiles, it not zoom to 50%, but to maximum depth. Other profiles (like
the Pentax for the Amsterdam photo sample) produces a extremly distortion at 50%.

You can download a sample image with the lense profile at http://www.terminal.io/tmp/4623/example.zip

Steps to reproduce:

- Open the photo
- zoom to 50%
- load the lens correction profile

Reported by cytrinox on 2013-03-26 20:29:29

[Beep6581]

Confirmed in Gentoo about two weeks ago. I noticed no errors in the saved image, but
the preview was broken. Will try to reproduce and bisect tomorrow.

Oduis hope you don't mind if I assign you.

Reported by entertheyoni on 2013-03-26 22:16:48

• Status changed: Accepted
• Labels added: Priority-Medium, Usability, OpSys-All
• Labels removed: Priority-Low

[Beep6581]

Sorry, as you know, since I switched to LR I don't do real patches any more, just builds.
However if any dev is seriously interested in taking over the LCP engine, I'd be happy
to have a Skype call to introduce him how the code works.

Reported by oduis@hotmail.com on 2013-03-29 10:51:01

[Beep6581]

Aww pity for us :]

From the forum:
by gs » Fri Mar 29, 2013 2:27 pm
(...)
I have the same problem when I apply the LCP profile to .nrw files from my P7100.
No problem instead with .NEF files.
RT4.0.10.36 on Win7_32
Saluti
Giorgio

Reported by entertheyoni on 2013-03-30 00:08:34

[Beep6581]

@2:

@odius: Ich schick' dir eine mail, sobald ich aus dem Urlaub zurück bin.

@english native speakers: I'll contact Odius, as soon as I'm back.

Reported by heckflosse@i-weyrich.de on 2013-03-30 00:20:50

[Beep6581]

Morgen Ingo,

Sehr schön! oduis at oliverduis.  Meine Skype-Name ist "oliverduis", dann können wir
den Code parallel via Bildschirmfreigabe anschauen.

Schönen Urlaub
Olli

Reported by oduis@hotmail.com on 2013-03-30 08:34:24

[Beep6581]

Had a first look. Broken preview is not caused by LCP, but by using 'Auto Fill', at
least with the sample file. But nevertheless, there also seems something wrong, when
not using 'Auto Fill'. Is is clearly visible, when viewing the upper left corner of
the sample picture at different zoom levels. 100% preview is not corrected at all.

Reported by heckflosse@i-weyrich.de on 2013-04-09 17:19:21

[Beep6581]

Reported by heckflosse@i-weyrich.de on 2013-04-09 17:19:52

[Beep6581]

Just for information. ImProcFunctions::getTransformAutoFill converges wrong direction
with sample picture and 50% preview, which results in about 5000% magnification of
the preview. At zoom-levels lower than 50% it converges correct, independent of the
zoom-level, to the same number every time. Will have a look ... but need some time!

Reported by heckflosse@i-weyrich.de on 2013-04-09 21:49:59

[Beep6581]

Reported by heckflosse@i-weyrich.de on 2013-04-09 21:50:17

• Status changed: Started