Main Area and Open Discussion > General Software Discussion

correction of distorted grid in image ??

<< < (3/3)

iphigenie:
I have seen several tools that are made to allow you to use your digital camera to take photos of pages in a book, for example, and which can clean up the distorsion. They might work for your kind of usage.

They're the "photocopy with your digital camera" / "scan with your digital camera" tools, I'll see if I can dig some up. Some have been mentioned in this forum this year, I'm sure I learned about them here.

tomos:
have you got an example image that we can experiment with - there might be a solution but it requires a bit of serendipity to find it.
-nudone (February 24, 2007, 08:26 AM)
--- End quote ---

okay,
heres a quarter of one image (A4 size), it's a plan of a stone circle - I've overlaid a heavy grid for clarity here, also tried to choose an area that wasn't too cluttered with stones

correction of distorted grid in image ??

If you think it's not too bad,
keep in mind it's a quarter of one image that's supposed to join up with four other A4 images to make one large drawing.
Also, it's at a scale of 1 to 100 so if it's one mm out thats multiplied by 100 ..

Note: they were drawn in the field this way, notebook-paper is already distorted from years of heated room to cold humidity & back, then photocopied & sent to me & I scan it - I know there must be a better way but thats the way it's happening for the foreseeable future.

Also, across 297mm (A4 page height) you can get a lot of wobbeldy bits going in various directions on one line  :D

It would be nice though, to be able to photograph a really large drawing & know you could correct it later.
I was working on some over 6 foot drawings a couple of years ago but that was all done by hand & photographically reduced later (professionally). no, it was scanned professionally, they used to be photographed (reprographed)

correction of distorted grid in image ??

EDIT:
PS. these are screenshots & so not to scale!

nudone:
hmm, that looks like i nightmare to correct perfectly.

if you can get away with it i think i'd try using a fresh perfect grid and then overlay the stones over the top of it - using something like photoshop that allows using layers and the usual blending and opacity features. this would look okay with the right amount of time spent on it but it wouldn't be an automatic one click process - so it's not really the solution you are looking for. it really depends on how much manual input you want to use.

tomos:
hmm, that looks like i nightmare to correct perfectly.

if you can get away with it i think i'd try using a fresh perfect grid and then overlay the stones over the top of it - using something like photoshop that allows using layers and the usual blending and opacity features. this would look okay with the right amount of time spent on it but it wouldn't be an automatic one click process - so it's not really the solution you are looking for. it really depends on how much manual input you want to use.
-nudone (February 24, 2007, 03:50 PM)
--- End quote ---

Ooops, maybe I didn't make that fully clear (its hard to think of everything  :o  ) but yes/no/(maybe):

I have found a relatively simple solution to current problem - I'm tracing/copying (vector) these dodgy scans, so, I overlay a 1cm grid - same as what original was drawn on.
They dont match due to the distortion, so as I move around the image I shift the scan so it lines up with the overlaid grid. Relatively easy & relatively accurate to boot.-tomos (February 24, 2007, 07:24 AM)
--- End quote ---

Yeah,
I'm actually "tracing" these scans,
so its not that I have to correct them in & of themselves -
I just have to be able to correct the final (vector) image &, as I say, I think the solution above is the best for me at the moment (& possibly forever!)

Navigation

[0] Message Index

[*] Previous page