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Thread: Hugin and PTGui suggestion for perfect (or better) stitch

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DorinDXN

Posts: 3116
Location: Timisoara, Romania
Registered: 14 Nov 2006
Hugin and PTGui suggestion for perfect (or better) stitch
Posted: 27 Jun 2007 at 11:13 GMT
updated: 27 Jun 2007 at 11:24 GMT
Hi all,

I was thinking of a way to obtain better stitch even in situation when finding the control points is hard or impossible.

So the easy way will be for developers of Hugin or PTGui to implement this idea and the hard way will be to manage with what we have.

It's about a grid which to be shown in some debug mode over the image and produced over the mapped file if such mode is turned on, the grid may look like this



and over image surce can look like



I don't show how it look in remapped file (deppends on projections so on..) I think that you get the picture.

As you see, each equare in the grid has a marker like 12 digits binary code so there can be 4096 different squares in grid shown as example (of course is no the best type that can be used)

After remmaping in multilayer tiff's with no blending, the user can see where Dorin will say that is minor stitching problem, so to fix that usually is need of some control points on that region, but if that region is, say an electric wire (or other broken featureles object) over the blue sky, then is difficult, so looking at those two adjacent images user can se if a certain portion of that wire will perfecttly join with other portion of that wire in other photo the vissible stitching error is gone, here comes the help of that grid, we recognise each square from remmaped picture and put a control point in source picture in Hugin/PTGui in both adjacent photos on that region which intersect the same square with featuresless object.

By swapping the set of sources photos with one with grid over, after using of automatic control points generation, then turn off any automatic fine-tune and estimation, the hard way is available now, but will be nice if such feature is implemented.

I know, must be some feature request where to post such ideas but due to my english and with hope of fine-tune this idea by contribution of others I've posted here

thanks for reading,
Dorin
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DorinDXN

Posts: 3116
Location: Timisoara, Romania
Registered: 14 Nov 2006
Re: Hugin and PTGui suggestion for perfect (or better) stitch
Posted: 29 Jun 2007 at 13:27 GMT
updated: 29 Jun 2007 at 13:47 GMT
Hi all again, I have great news for you, I hope, the idea works perfectly, yes, please read again perfetcly. I will provide more images and hope a tutorial, as a disclosure now.. I used a decimal labeled grid seems that in base 10 is much easier to read for non sillicon entities smile , much dense than in images posted but having only one label for 50 squares, traspearent over the images, like milimmeter paper or so, used on blueprints , it'is like a magic feedback of stitching and you can fine-tune to achieve perfect stitch (of course if isn't parallax or movement the cause.

post you soon smile

Dorin

p.s. the label is like A1234 where A is for a certain photo so A1234 and B1234 means regions from different photos, that helps to get feedback from direct stitched jpg or tif, no need for multilayer tiffs.

D.
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DorinDXN

Posts: 3116
Location: Timisoara, Romania
Registered: 14 Nov 2006
Re: Hugin and PTGui suggestion for perfect (or better) stitch
Posted: 30 Jun 2007 at 11:56 GMT
updated: 30 Jun 2007 at 12:04 GMT
Hi I've promised some pictures, is not much, but..

if the Hugin project is in
D:\pano
then the normal source photos will be in
D:\Pano\Photos
and the gridded photos will be in
D:\Pano\grPhotos

by renaming the folders you can on/off the grid

In this stiched rectilinear photo, there are some problems on electric wire, each source photo was grided and labeled




3MB download!


in order to fix one big problem there is need for some control poitns. If you look where the wire are broken you find that is need for a control point, both stitched/remaped and source photo has the same grid one way is to place one control point in that region shown in





by placing other control points in the same manner the result is




3MB download!


The good thing is that after the sticth, if you want better stitch the stitched grid will tell you where those points on grid must be fine-tuned manually.

Important, with grid on you must not use any automatic fine-tune becouse of grid, also instead of A1234 label could be someting like 1-1234 where the number 1- to indicate the photo in Hugin,

If you want to try to apply this method you'll need a way to put that grid over the source photo, mine was a simple grid with a numbered label at each 25 (5x5) squares put with transparency over the source photo, on a scale from 0 to 255 (0 beeing completely transparent) level was about 40.

I hope that someone here to explain how to make a script to do a similar grid over in Photoshop used by the majority of panographers, if no one provide such instructions I can prepare a archive with such grids as TGA with transparency, then is a simple matter of import over and save flattened image in PS.

I'm waiting for thoughts and ways to improve this idea, such as, a radial grid will help much than a square grid? so on..

thanks,
Dorin
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