imgdiff

• Next the program makes the two inputs the same size:

        my $xmin= min($size[0][0], $size[1][0]);
        my $ymin= min($size[0][1], $size[1][1]);

        for (0 .. 1) {
          next if $size[$_][0] == $xmin && $size[$_][1] == $ymin;
          run("pnmscale -xysize $xmin $ymin $pnm[$_] > $tmp");
          run("mv $tmp $pnm[$_]");
        }

• pnmscale scales an image to the specified dimensions

• Afterwards, the program does the actual subtraction using pnmarith

• which we saw already

• I don't know why I used run("mv ...") here instead of rename

• The program does some option processing, but there's nothing new there

Next

Menu

Copyright © 2012 M. J. Dominus