Batch mode auto white balance
Create the file
~/.gimp-2.8/scripts, with the following content:
; Usage: ; gimp -i -b '(batch-levels-stretch "*.JPG")' -b '(gimp-quit 0)' (define (batch-levels-stretch pattern) (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-levels-stretch drawable) (gimp-file-save RUN-NONINTERACTIVE image drawable filename filename) (gimp-image-delete image)) (set! filelist (cdr filelist)))))
Then create a folder with a copy of your pictures, and run the following command in it:
gimp -i -b '(batch-levels-stretch "*.JPG")' -b '(gimp-quit 0)'
Make sure *.JPG matches your pictures (case sensitive).
And it will overwrite the pictures, one by one, with the processed image.