Rectifying distortion of scans

[Jemiba]

Especially when taking copies or photos of collected volumes of magazines, there's
often the problem of distortion near to the fold. The nearer to the fold, the more
equalisation is needed. Which graphic software offers the best (and easiest) solution ?

 

[SOC]

I think GIMP will let you skew the image along various axis. I can play with that image there later this afternoon and see 1) if it works and 2) how complicated it is.

 

[SOC]

OK GIMP has a perspective tool that seems to want to be useful in fixing the problem, but it seems to be way more trouble than I thought it'd be.

 

[Jemiba]

Thanks for your effort ! Seems GIMP behaves similar to CorelDraw in this regard... :
tried to cut the photo into strips and expand every single stripe to a different amount.
But doing this manually is a painstaking task with an uncertain result.
I thought of it as a problem, that should occur quite often, especially today, where
OCR software is said to be working with snapshots from handycams, which probably
often are distorted.

 

[Hobbes]

It's a bit old, but this thread on Slashdot offers some possibilities:
http://ask.slashdot.org/story/09/09/27/199251/software-to-flatten-a-photographed-book

 

[Jemiba]

with the link, I only get "Internal Server Error" in the moment ...

 

[Hobbes]

Slashdot has occasional hiccups, I tried just now and the link works.

 

[Jemiba]

Ok, works now ! Will have a look through ..

 

[overscan (PaulMM)]

Most of the free software they discuss is aimed at relatively minor scan adjustments like deskewing pages at angles.


You can manually fix your image with any filter with a grid deformation e.g. Photoshop "Warp". Simply put some guide lines down and warp until the lines are straight and the text is readable.


http://www.photoshopessentials.com/photo-effects/collage-warp/


Its hard to automate however.

 

[Jemiba]

Thanks for that clue, Paul. Will try to get access to my daughters computer,
as I don't have Photoshop on my own computer. May be hard, but I think,
it's worth a try ...