light_correct - correct illumination errors on set of images

       The National Gallery and Birkbeck College, 1989-1996.

                                                   14 Oct 1996                                  LIGHT_CORRECT(1)

       The  first  argument  should  be  an image of a piece of grey card, subsequent arguments should be images
       taken with the same lighting set-up which need correcting. The corrected  images  are  written  to  files
       prefixed with "ic_".

       For example, suppose you have a directory with the following files in:

         example% ls
         dat1.1.v dat1.2.v dat2.1.v dat2.2.v dat3.1.v dat3.2.v
         dat4.1.v dat4.2.v grey.v

       then run light_correct like this:

         example% light_correct grey.v dat*.v

       to generate this:

         example% ls
         dat1.1.v dat1.2.v dat2.1.v dat2.2.v dat3.1.v dat3.2.v
         dat4.1.v dat4.2.v grey.v
         ic_dat1.1.v ic_dat1.2.v ic_dat2.1.v ic_dat2.2.v ic_dat3.1.v
         ic_dat3.2.v ic_dat4.1.v ic_dat4.2.v

       light_correct  works  by  smoothing  out the grey card image, finding grey-mean/pixel for each point, and
       then multiplying the result by all the following images. It also removes any .desc files it generates, to
       avoid problems with im_global_balance(3).

       light_correct - correct illumination errors on set of images

       returns 0 on success and non-zero on error.

vipsheader(1), vips(1)

light_correctgreyimage1image2image3...