[NTG-pdftex] Creating identical PDF files with different pdfTeX runs

Hartmut Henkel hartmut_henkel at gmx.de
Thu Mar 16 20:08:02 CET 2006

On Thu, 16 Mar 2006, Frank Küster wrote:

> Hartmut Henkel <hartmut_henkel at gmx.de> wrote:
> Yes, we definitely need the original file.
> > Maybe some crosscorrelation between images with some given tolerance
> > limit would be safer.
> Any hints what I could use for such a purpose?

just found from Netpbm:

       pnmpsnr - compute the difference between two portable anymaps

       pnmpsnr [pnmfile1] [pnmfile2]


       Reads two PBM, PGM, or PPM files, or PAM equivalents, as input.
       Prints the peak  signal-to-noise  ratio  (PSNR)  difference
       between the two images. This  metric is typically used in image
       compression papers to rate the distortion between original and
       decoded image.

And in ImageMagick there is a -compose operator with Difference and
Multiply option.

Regards, Hartmut

More information about the ntg-pdftex mailing list