GIMP – batch resize images

Posted by 7sins|Linux, Miscellaneous|1 Comment

Recently I had the need to resize a lot of images to a specific size for presentation. Since I use GIMP a lot I tried to resize them using GIMP. But manually resizing every one of them is a tedious job.

It was then that I realised that I could do a batch resize of the images, but that I did not know how to do that using GIMP.
A little googling around I came across this piece of script which just works wonderfully.

(define (batch-crop pattern width height xoffset yoffset)
        (let*   ((filelist (cadr (file-glob pattern 1))))
                (while (not (null? filelist))
                        (let* ( (filename (car filelist))
                                (image (car (gimp-file-load RUN-NONINTERACTIVE filename filename)))
                                (drawable (car (gimp-image-get-active-layer image)))
                              )
                                (gimp-image-crop image width height xoffset yoffset)
                                (gimp-file-save RUN-NONINTERACTIVE image drawable filename filename)
                                (gimp-image-delete image)
                        )
                        (set! filelist (cdr filelist))
                )
        )
)

To use the script follow the below mentioned steps

1. Create a file called batch-crop.scm in the folder ~/.gimp-2.6/scripts
2. Execute the script in the directory containing the images using

   :~$ gimp -i -b '(batch-crop "*.png" width height x-offset y-offset)' -b '(gimp-quit 0)'
   

   where

   • width: Width of the resized image
   • height: Height of the resized image
   • x-offset: Left side margin to be removed
   • y-offset: Top side margin to be removed

   For instance to resize a bunch of different sized images to 1024×768 with no cropping use the following

   :~$ gimp -i -b '(batch-crop "*.jpg" 1024 768 0 0)' -b '(gimp-quit 0)'
   

Hope this helps you with your batch resizing