my $nr = $1 if $hires =~ m{(\d+)\.\w+$} || warn "can't find number in $hires";
next unless $nr;
my $file = slide_jpg( $factor => $nr );
my $nr = $1 if $hires =~ m{(\d+)\.\w+$} || warn "can't find number in $hires";
next unless $nr;
my $file = slide_jpg( $factor => $nr );