decode bitcoin OP_RETURN

bitcoin_decode.php

<?php
 $transaction_id = $argv[1];
 $url = "https://blockchain.info/tx/$transaction_id?show_adv=true&format=json";
 $result = file_get_contents($url);
 $resultJSON = json_decode($result, true);
 function hex2str($hex) {
        $str = '';
        for($i=0;$i<strlen($hex);$i+=2) $str .= chr(hexdec(substr($hex,$i,2)));
        return $str;
 }
 //zero false positives that there is a hidden message
 function fetchZeroValMSG($resultJSON){
        $outgoing_transaction = $resultJSON['out'];
        #print_r($outgoing_transaction);
        foreach($outgoing_transaction AS $this_transaction){
                #print_r($this_transaction);
                if($this_transaction['value'] == 0){
                        $code = $this_transaction['script'];
                        echo hex2str($code)."\n";
                }
        }
 }
 function fetchPotentialMSG($resultJSON){
        $outgoing_transaction = $resultJSON['out'];
        foreach($outgoing_transaction AS $this_transaction){
                $code = $this_transaction['script'];
                $str2 = substr($code, 6);
                $code = $str2;
                unset($str2);
                $str3 = substr($code, 0, -4);
                $code = hex2str($str3);
                unset($str3);
                echo $code;
        }
 }
fetchPotentialMSG($resultJSON);