ahex

ahex.js

var id = "4df67d6dcc19519d0f098bd6"

var ahex = id.split('').map(function(a) {
	// isNumber
	if((a - 0) == a && a.length > 0) {
		// g because 0 would collide with hex f. 0->"g",1->"h","a"->"a" etc
		return String.fromCharCode("g".charCodeAt(0)+Number(a));
	}
	return a;	
}).join('');
var unhex = ahex.split('').map(function(a) {
	// character is encoded number, larger than "f"
	if(a.charCodeAt(0) > "f".charCodeAt(0)) {
		return String.fromCharCode("0".charCodeAt(0) + a.charCodeAt(0)-"g".charCodeAt(0));
	}
	// character less than "g" so part of hex
	return  a;
}).join('');

console.dir(id);
console.dir(ahex);
console.dir(unhex);

ahex.php

<?php
$new_ahex_id = null;
$ahex_id = "4df67d6dcc19519d0f098bd6";
echo $ahex_id."\n";
$new_ahex_id = '';
for ($i=0; $i < strlen($ahex_id); $i++) {
  if (is_numeric(substr($ahex_id, $i, 1))) {
    $char = chr(ord("g") + (int)substr($ahex_id, $i, 1));
    $new_ahex_id .= $char;
  } else {
    $new_ahex_id .= substr($ahex_id, $i, 1);
  }
}
echo $new_ahex_id."\n";
$unhex = '';
for ($i=0; $i <strlen($ahex_id); $i++) {
  if (ord(substr($ahex_id, $i, 1) ) > ord("f")) {
    $char = chr(ord("0") + ord(substr($ahex_id, $i, 1)) - ord("g")) ;
    $unhex .= $char;
  } else {
    $unhex .= substr($ahex_id, $i, 1);
  }
}
echo $unhex."\n";
?>