How to remove duplicate values from a multi-dimensional array in PHP

Array
(
    [0] => Array
	(
	    [0] => abc
	    [1] => def
	)

    [1] => Array
	(
	    [0] => ghi
	    [1] => jkl
	)

    [2] => Array
	(
	    [0] => mno
	    [1] => pql
	)

    [3] => Array
	(
	    [0] => abc
	    [1] => def
	)

    [4] => Array
	(
	    [0] => ghi
	    [1] => jkl
	)

    [5] => Array
	(
	    [0] => mno
	    [1] => pql
	)

)

function multi_unique($array) {
        foreach ($array as $k=>$na)
            $new[$k] = serialize($na);
        $uniq = array_unique($new);
        foreach($uniq as $k=>$ser)
            $new1[$k] = unserialize($ser);
        return ($new1);
    }

$input = array_map("unserialize", array_unique(array_map("serialize", $input)));

function array_unique_multidimensional($input)
{
    $serialized = array_map('serialize', $input);
    $unique = array_unique($serialized);
    return array_intersect_key($input, $unique);
}

function arrayUnique($myArray){
    if(!is_array($myArray))
        return $myArray;

    foreach ($myArray as &$myvalue){
        $myvalue=serialize($myvalue);
    }

    $myArray=array_unique($myArray);

    foreach ($myArray as &$myvalue){
        $myvalue=unserialize($myvalue);
    }

    return $myArray;

}