[Hdri] correction for barrel distortion

[Greg Ward]

Haha.  Very funny, indeed!

I just tried the lens warp with Photoshop CS2 on my Mac, and it did  
preserve the Exif information, so I think that process could work.

Pcomb does support limited filtering, which could include some  
warping, but you have to keep the scans within 32 pixels of each  
other (or so), and that might be a problem.  You would also want to  
implement a bicubic filter, I suppose.

-Greg

> From: "Martin Moeck" <MMoeck at engr.psu.edu>
> Date: January 17, 2006 1:40:26 PM PST
>
> No luck with Photoshop lens corrections. This is like poor freehand  
> drawing. All gridlines are not vertical or horizontal, but warped  
> in interesting ways.
>
> Each square with barrel distortion has to be corrected  
> individually. Greg needs to do take care of this right now :) This  
> community needs a tool to shift pixels in a Radiance image around.  
> Input could be a black and white grid image showing the barrel  
> distortion. Output would be the image with straight lines.
>
> Greg, I can help you with the command line :) :
>
> pcomb -f barrel.cal barrelgrid.pic original.hdr > corrected.hdr
>
> See, Greg, we are already halfway there :)
>
> Martin