$xdiffHash = substr( xdiff_string_rabdiff( $input, '' ), 0, 4 );
$dhb = new DiffHistoryBlob;
$myHash = $dhb->xdiffAdler32( $input );
$xdiffHash = substr( xdiff_string_rabdiff( $input, '' ), 0, 4 );
$dhb = new DiffHistoryBlob;
$myHash = $dhb->xdiffAdler32( $input );