if ($img =~ m#.*/(.*)#) {
    $name = $1;
}
else {
    # didn't match!
}

##</code><code>##

use Benchmark;

timethese(1000000, {
    'regexp' => sub { my($file) = $img =~ m#.*/(.*)# },
    'substr' => sub { my $file  = substr $img, rindex($img, '/') + 1 }
});

##</code><code>##

Benchmark: timing 1000000 iterations of regexp, substr...
    regexp: 11 secs (11.18 usr  0.00 sys = 11.18 cpu)
    substr:  4 secs ( 5.67 usr  0.00 sys =  5.67 cpu)