Zoltán,
I am eager to know what other users have to say, whether on the list or
directly to you, Zoltán.
I have a similar application (stamps for collectors). I have
experimented with various "green screen" techniques for years, and using
other programs as well, but I have never been able to find anything that
can fully do what I need to do. The problem for me is that sometimes
the printed design of the stamp (which can be various colors), or the
cancellation/postmark on the stamp goes to/over the edge of the stamp
paper. Thus at that point (near the edge) there are problems with
selections "eating into" the stamp area, etc., such as the selection
following the area of the postmark into the stamp. We have also not
been able to completely eliminate all vestiges of background color right
up to the edge of the stamp's paper (keep in mind that on old stamps,
not all edges are absolutely clear cut as they are on a modern stamp) --
this may be similar to Zoltán's problems at the edges of coins if the
edge of the coin is not perfectly smooth.
Since we never found a satisfactory solution in "old" GIMP we did not
attempt to automate it back then (as Zoltán did), thus we don't have the
problem of the automation no longer working well or quickly.
However, our original problem remains as much as ever. We can get "sort
of close", but that's just not good enough. And we need something we
can use for making tens of thousands of stamp images.
I will watch this thread with interest.
Zoltán, I welcome learning any advice you can give as you solve your
problem.
Jay Smith
On 03/23/2021 07:15 PM, Zoltán Kluik via gimp-user-list wrote:
Dear GIMP users,
I would like to ask your help regarding removing background and change it
to white.
I'm dealing with coin pictures mainly medieval silver coins. I take the
photo about coins with green / dark green background. In the past on Ubuntu
I used the GIMP 2.8.16 version where I applied the foreground selection
tool. Here I just simple rounded the coin, press enter and the program
after some seconds selected my coin. I loved this method, because it takes
only seconds to select the coin.
Last year I have upgraded GIMP to version 2.10.22, but from this time I
have a big problem with time consumption and also with the quality of the
changing the background. Now in 2.10.22 I open a picture, using foreground
selection tool, but in this version there is a motor feature where I can
select Global- and Levin matting. I use both with iteration value 1. First
Global is selected, coin is rounded, pressing enter, selecting the
foreground with the mouse, again pressing enter. Here the problem is that
under the coin where the green background’s colour was a little bit darker
there are green dots. So after Global, I apply the Levin matting. With
this the dots are deleted, good, but where it is not selected the coin,
there the surface (mainly at the edge) is not the original, blurred or not
as the original was. Here I can use the adding to background selection or
adding to the background within extra zoom possibility to make sharper the
edges. Finally after 10 minutes however it is the same result as in 2.8.16
was 30 seconds and automatically.
So what did I wrong or how I should do to make this process easier and
faster as it was in the earlier version?
Thank You in advance for Your advice!
Zoltan
Zoltán Kluik ezt írta (időpont: 2021. márc. 23.,
K 14:10):
Dear GIMP users,
I would like to ask your help regarding removing background and change it
to white.
I'm dealing with coin pictures mainly medieval silver coins. I take the
photo about coins with green / dark green background. In the past on Ubuntu
I used the GIMP 2.8.16 version where I applied the foreground selection
tool. Here I just simple rounded the coin, press enter and the program
after some seconds selected my coin. I loved this method, because it takes
only seconds to select the coin.
Last year I have upgraded GIMP to version 2.10.22, but from this time I
have a big problem with time consumption and also with the quality of the
changing the background. Now in 2.10.22 I open a picture, using foreground
selection tool, but in this version there is a motor feature where I can
select Global- and Levin matting. I use both with iteration value 1. First
Global is selected, coin is rounded, pressing enter, selecting the
foreground with the mouse, again pressing enter. Here the problem is that
under the coin where the green background’s colour was a little bit darker
there are green dots. So after Global, I apply the Levin matting. With
this the dots are deleted, good, but where it is not selected the coin,
there the surface (mainly at the edge) is not the original, blurred or not
as the original was. Here I can use the adding to background selection or
adding to the background within extra zoom possibility to make sharper the
edges. Finally after 10 minutes however it is the same result as in 2.8.16
