#!/usr/bin/perl
# Author: Peter R. Wood, http://prwdot.org/

my $base = "/base/directory/here";
my $du   = "du -sb ";

my %stats;

opendir( BASE, $base );
foreach my $album ( grep( !/^\./, readdir(BASE) ) ) {
    my ( $bytes, $name ) = split( /\s+/, `$du $base/$album` );
    chomp($bytes);
    my $count = `ls $base/$album | wc -l`;
    chomp($count);
    my $ratio = sprintf( "%.0d", $bytes / $count );
    $stats{$album} = $ratio;
}
closedir(BASE);

foreach my $album ( sort { $stats{$a} <=> $stats{$b} } keys(%stats) ) {
    print "$album: $stats{$album}\n";
}