This seems to work even without the structuring comments (%%EndSetup, %%Page). The following worked for me: 
#!/usr/bin/perl    

$usage="Usage: $0 x1 y1 x2 y2 file.ps";

$x1=shift @ARGV;
$y1=shift @ARGV;
$x2=shift @ARGV;
$y2=shift @ARGV;

($x1 && $y2 && $x2 && $y2 ) or
    die "$usage\n";

$w=$x2-$x1;
$h=$y2-$y1;

$flag=0;

while (<>) {
    if (/^%%BoundingBox:/) {
        print "%%BoundingBox: 0 0 $w $h\n";
        print "-$x1 -$y1 translate\n";
        print "$x1 $y1 moveto $x1 $y2 lineto $x2 $y2 lineto $x2 $y1 li
+neto closepath\n";
        print "clip\n";
        $flag=1;
    }
    else {
        print;
    }
}

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In reply to Re: Cropping a postscript file by Anonymous Monk
in thread Cropping a postscript file by ZZamboni

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