my @cmd = ( 'convert,
            $thumbNail1
            qw[( +clone 
                 -threshold -1 
                 -virtual-pixel black 
                 -spread 10 
                 -blur 0x3
                 -threshold 50%
                 -spread 1
                 -blur 0x.7
               ) 
               +matte 
               -compose Copy_Opacity
               -composite
            ], $thumbNail2 );

system(@cmd) == 0
    or die "Couldn't launch [@cmd]: $!/$?";