@images = ({Name,'a',Size,2},{Name,'b',Size,3},{Name,'c',Size,2},{Name,'d',Size,3});

##</code><code>##

my @duplicates = grep{$c{$_->{Size}}++ && $c{$_->{Size}}>1}@images;

##</code><code>##

for (@duplicates)	{
	print join " ", values %$_, "\n";
}