An easy horizon straightening tool

[Bmachine]

An easy horizon straightening tool

by Bmachine » Sat Oct 23, 2010 10:53 pm

I've been using APP for many years and it never ceases to amaze me how great this program is. Most of my panos are nature/landscape types and they are all shot handheld. Only horizontal shots of between 100 and 180 degrees. But somehow APP nearly always manages to assemble an amazing pano out of these source images.

The only problem I have is that, because they are shot handheld, APP sometimes has a hard time giving me a straight horizon. The vertical lines tool rarely works well for this task. It seems it never gets a clean straight line all the way accross the pano. If it's just a simple curve like a banana, you can fix it with the Center Point tool. But if it is more of an S shape, it is much more difficult. And for this kind of subject, I can't use the Planar projection which has more tools available. So I usually go in the CP editor and remove points in clouds and add some where it may help. And that usually works fine. BUT... when you have a lot of panos to create, this ends up taking quite a lot of time.

I have asked for this already a few years ago but with no success so it's time to bring it back. Would it be possible to simply use a bezier type of line to trace the horizon as it comes out of the initial detection and then have APP straighten the image based on that?

Below is an example of an initial detection.
Then a line drawn across the horizon I want to end up with.
And finally the resulting clean image (still not perfect in my example) which APP would then generate based on that user drawn hz line.

Thank you.

Bo

Last edited by Bmachine on Sat Oct 23, 2010 11:04 pm, edited 1 time in total.

[gerardm]

by gerardm » Sun Oct 24, 2010 1:36 am

I second this idea. I recently did many large water images. The lack of control points made the image "un-straightable" I tried every tool. I ended-up using puppet warp in CS5. On 10+gigapixel images, puppet warp was painfully slow.

[DrSlony]

by DrSlony » Sun Oct 24, 2010 2:16 am

http://www.autopano.net/forum/t3135-curvature-tools
http://www.autopano.net/forum/p26163-2008-07-13-16-12-57#p26163

Regards

[Bmachine]

by Bmachine » Sun Oct 24, 2010 3:00 am

Ha! Perfect, DrSlony. Great minds think alike. ;-)

But reading your second post, the last reply is from Alexandre who says "Good idea DrSlony and easy to code." Well ??? If it was easy to code two years ago, where is it?

Allo, Alexandre ???

Bo

[AlexandreJ]

by AlexandreJ » Mon Oct 25, 2010 8:24 am

Yes, who's calling ?

We are always concentrating totally on the final release and I don't want to spend now some time on any new feature. But after the release, really, it will be the right time to do that.

[Bmachine]

by Bmachine » Mon Oct 25, 2010 4:18 pm

Merci Alexandre!

I certainly understand your desire to focus on 2.5. That new version is awesome, btw!

But promise us that it wont be another 2 years before we get the horizon tool, ok? ;-)

Thannk you very much.

Bo

[Bmachine]

by Bmachine » Mon Oct 25, 2010 4:28 pm

Wait, actually, it is THREE years! I have just found my original request for this tool which dates back to 2007... ;-)

http://www.autopano.net/forum/t2229-straightening-out-the-horizon

Thanks Alex!

PS: I re-read that old post and there were some good suggestions on how, in case of handheld landscape panos, it is better to keep cps on far objects rather than near ones.

[Bmachine]

by Bmachine » Wed Feb 15, 2012 8:50 pm

So, Alexandre....

Is there any progress on this "Simple to code" issue by any chance?

Has it been incorporated in 2.6 and I did not notice?

Thank you!

Bo

[klausesser]

by klausesser » Wed Feb 15, 2012 9:35 pm

So, Alexandre....

Is there any progress on this "Simple to code" issue by any chance?

Has it been incorporated in 2.6 and I did not notice?

Thank you!

Bo

Ho Bo!

I´m not sure to understand your question: you want a tool for straightenig the horinzon? But it´s already there since the early days of APP . .

Take the vertical line tool and draw a vertical line somewhere - these lines have yellow horizontal lines. Connect these yellow horizontal lines layed over the curved horizont for straightening it.
That´s all.

http://www.autopano.net/wiki-en/action/view/Autopano_Giga_-_Panorama_Editor_-_Geometry_Correction#Vertical_lines

Not being explained here really well . .

Hope, i got what you meant . .

best, Klaus

Last edited by klausesser on Wed Feb 15, 2012 9:41 pm, edited 1 time in total.

[Bmachine]

by Bmachine » Thu Feb 16, 2012 1:09 am

Thanks Klaus,

But if you read my post from the beginning, you will see that this is different from the vertical lines tool. That tool does not work well for straightening out horizons. Sometimes it does but most of the time not. Alexandre recognized this and promised that the tool I described was "easy to code". That was 4 years ago...

Note that DrSlony had separately asked for the same thing. Check his posts links above.

Bo

[klausesser]

by klausesser » Thu Feb 16, 2012 4:35 pm

Thanks Klaus,

But if you read my post from the beginning, you will see that this is different from the vertical lines tool. That tool does not work well for straightening out horizons. Sometimes it does but most of the time not. Alexandre recognized this and promised that the tool I described was "easy to code". That was 4 years ago...

Note that DrSlony had separately asked for the same thing. Check his posts links above.

Bo

Hi Bo!

I used it several times and it worked out very fine! The yellow lines should follow the curve of your horizont. In my case it made it perfectly straight.
Maybe you must make lots of lines!

best, Klaus

Last edited by klausesser on Thu Feb 16, 2012 4:35 pm, edited 1 time in total.

[leifs]

by leifs » Thu Feb 16, 2012 10:17 pm

I used it several times and it worked out very fine! The yellow lines should follow the curve of your horizont. In my case it made it perfectly straight.
Maybe you must make lots of lines!

best, Klaus

I tried it on this pano, where it is essential to get the horizon straight and horisontal. And I could not make it work satisfyingly and resorted to photoshopping.
A better make-the-horizon-straight-and-horisontal-tool would be welcome !
http://www.rundskuer.no/panotour/rundefyr/index.html

leifs

[klausesser]

by klausesser » Fri Feb 17, 2012 12:58 am

I used it several times and it worked out very fine! The yellow lines should follow the curve of your horizont. In my case it made it perfectly straight.
Maybe you must make lots of lines!

best, Klaus

I tried it on this pano, where it is essential to get the horizon straight and horisontal. And I could not make it work satisfyingly and resorted to photoshopping.
A better make-the-horizon-straight-and-horisontal-tool would be welcome !
http://www.rundskuer.no/panotour/rundefyr/index.html

leifs

Hi!

Definitely the best way to get a straight horizont is to level the camera carefully . . . :cool:

But as i said: i had good experiences using the vertical line tool.

best, Klaus

[Bmachine]

by Bmachine » Fri Feb 17, 2012 7:58 pm

I have found the vertical line tool to be a hit and miss for horizons. For straightening building, it looks good. But for horizons, it often seems to be making each line straight by itself but does not move them all so they are at the same height relative to the bottom of the frame.

And that is probably why it is called "Vertical lines" tool and not "Horizon" tool.

[klausesser]

by klausesser » Fri Feb 17, 2012 8:35 pm

And that is probably why it is called "Vertical lines" tool and not "Horizon" tool.

Thanx for the information - i didn´t realise that . . :D:cool:

Nevertheless: i my case it works alright for straightening a horizon too when you have a curved one.
Maybe it depends a lot on the way it´s curved . . . !?

But as i said already: level the camera and you HAVE a straight horizon

best, Klaus

[leifs]

by leifs » Fri Feb 17, 2012 10:40 pm

But as i said already: level the camera and you HAVE a straight horizon
best, Klaus

not always after it is "optimized".
then the vertical-line-game is like chasing rabbits:
the fix is ok but another place on the horizon which was ok is no longer ok.

leifs

[Bmachine]

by Bmachine » Sat Feb 18, 2012 12:14 am

But as i said already: level the camera and you HAVE a straight horizon
best, Klaus

not always after it is "optimized".
then the vertical-line-game is like chasing rabbits:
the fix is ok but another place on the horizon which was ok is no longer ok.

leifs

Exactly!

[klausesser]

by klausesser » Sat Feb 18, 2012 5:04 pm

But as i said already: level the camera and you HAVE a straight horizon
best, Klaus

not always after it is "optimized".
then the vertical-line-game is like chasing rabbits:
the fix is ok but another place on the horizon which was ok is no longer ok.

leifs

Exactly!

Are we talking about a spherical or a rectilinear pano?

best, Klaus

[Bmachine]

by Bmachine » Mon Feb 20, 2012 3:28 am

I almost always use spherical.

Bo

[leifs]

by leifs » Mon Feb 20, 2012 9:31 am

I'm shooting spheres with 50-100mm equivalents

leifs

[CheeseAndJamSandwich]

by CheeseAndJamSandwich » Sat Mar 03, 2012 7:54 pm

I too have had several panos i couldn't straighten.
And as i've talked about in a separate request (http://www.kolor.com/forum/t7906-horizon-tool), a Horizon 'Washing Line' tool would be the easiest to use by a very long way...:
Have a way of manually putting down special horizon control points which will then line up with the theoretical horizon line, distorting/warping the image to make it right.

But again, i'd love for this functionality to deal with each image, so that the horizon will always be lines up, with out steps, which i've see soooooo many times when stitching a very flat or ocean horizon.

I can't always have my pano head/tripod with me so i'm always going to shoot hundreds of hand-held panos... which mostly work perfectly with autopano... apart from the very flat/ocean ones...

Last edited by CheeseAndJamSandwich on Sat Mar 03, 2012 7:57 pm, edited 1 time in total.

[Bmachine]

by Bmachine » Thu May 03, 2012 12:22 am

Any news on this Alexandre?

Apart from this, APP/APG is more awesome in each release!

Bo

[Bmachine]

by Bmachine » Mon Jul 23, 2012 1:03 am

Hello? Hello? Hello?

Allô, allô, ici la Terre... Allô, j'appelle fusée lunaire...