my $pbm = "/tmp/$barcode.pbm";
open(my $from, '<', "templates/$size.svg");
-open(my $to, '|-', "convert -density $density - $pbm");
+open(my $to, '|-', "convert -units PixelsPerInch -density $density - $pbm");
while(<$from>) {
s/1301272944/$barcode/gs && warn "# barcode $barcode\n";
s/##call1##/$call1/gs && warn "# 1: $call1\n";