On Wed, 31 Aug 2016 01:10:22 +0200, =?UTF-8?Q?Manuel_Ace=C3=B1a?= wrote:

To developers of GIMP:

*Process or batch editing - Barrel distortion* I detected something that I think could help significantly large number of users:

Almost all do photos to documents with the mobile phone, and we also thought of using a camera installed permanently for it, being much faster than the scanner table. But we found that the pictures are distorted, generally convex, whether we do with a smartphone or a traditional camera.

Many smartphone apps include automatic document edge detection, but have not found any way to correct lens distortion (barrel distortion). This is a very serious problem when we take pictures of planes, which are invalidated, or when we want to take pictures of any image that must remain correctly proportioned.

GIMP itself that corrects barrel distortion quickly and easily using a filter, but only when a single image editing. Unfortunately, you can not do that function working in batches, when I think that developers would be simpler than the batch also included that role, assigning a group of photos -made with a fixed camera one correction (Example: "Barrel distortion - Main: - 22 ")

*I request that you make every effort to include this feature among supported in batch editing.*

*Thank you* for providing such an *excellent program!!!*

GIMP isn't the right tool for the job. You'd be a lot better off using darktable or rawtherapee, which are designed for batch processing, for that purpose. Both of these tools work on JPEGs as well as RAW files, and if you're always using the same lens at the same focal length (with the same distortion characteristics) you can save the parameters and easily apply them to more shots in the future.

Robert Krawitz                                     

***  MIT Engineers   A Proud Tradition   http://mitathletics.com  ***
Member of the League for Programming Freedom  --  http://ProgFree.org
Project lead for Gutenprint   --    http://gimp-print.sourceforge.net

"Linux doesn't dictate how I work, I dictate how Linux works."
--Eric Crampton

On Wed, Aug 31, 2016 at 2:10 AM, Manuel Aceña wrote:

GIMP itself that corrects barrel distortion quickly and easily using a filter, but only when a single image editing. Unfortunately, you can not do that function working in batches, when I think that developers would be simpler than the batch also included that role, assigning a group of photos -made with a fixed camera one correction (Example: "Barrel distortion - Main: - 22 ")

*I request that you make every effort to include this feature among supported in batch editing.*

http://www.alessandrofrancesconi.it/projects/bimp/

Please just use it.

Alex

On Wed, Sep 7, 2016 at 9:58 PM, Alexandre Prokoudine wrote:

On Wed, Aug 31, 2016 at 2:10 AM, Manuel Aceña wrote:

GIMP itself that corrects barrel distortion quickly and easily using a filter, but only when a single image editing. Unfortunately, you can not do that function working in batches, when I think that developers would be simpler than the batch also included that role, assigning a group of photos -made with a fixed camera one correction (Example: "Barrel distortion - Main: - 22 ")

*I request that you make every effort to include this feature among supported in batch editing.*

http://www.alessandrofrancesconi.it/projects/bimp/

Please just use it.

Another way to approach such problems if one can do unix shell scripting is to use the GEGL binary directly.

$ ls IMG_1883.JPG IMG_1885.JPG IMG_1887.JPG $ mkdir output
$ for input in *.JPG; do echo $input;gegl $input -o output/$input -- lens-distortion main=-23 zoom=1.2 ; done # make and drink tea

Note that GEGL loads/quries all its plugins on startup; slowing the this type of batch processing down since a new GEGL instance is created for each image.

/pippin

On Wed, Aug 31, 2016 at 01:10:22AM +0200, Manuel Aceña wrote:

To developers of GIMP:

*Process or batch editing - Barrel distortion* I detected something that I think could help significantly large number of users:

Almost all do photos to documents with the mobile phone, and we also thought of using a camera installed permanently for it, being much faster than the scanner table. But we found that the pictures are distorted, generally convex, whether we do with a smartphone or a traditional camera.

Many smartphone apps include automatic document edge detection, but have not found any way to correct lens distortion (barrel distortion). This is a very serious problem when we take pictures of planes, which are invalidated, or when we want to take pictures of any image that must remain correctly proportioned.

GIMP itself that corrects barrel distortion quickly and easily using a filter, but only when a single image editing. Unfortunately, you can not do that function working in batches, when I think that developers would be simpler than the batch also included that role, assigning a group of photos -made with a fixed camera one correction (Example: "Barrel distortion - Main: - 22 ")

*I request that you make every effort to include this feature among supported in batch editing.*

*Thank you* for providing such an *excellent program!!!*

See also if the "unpaper" program (found under all main linux distros) could be useful for your work...

Marco Ciampa

I know a joke about UDP, but you might not get it.

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 GNU/Linux User #78271
 FSFE fellow #364

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