Сергей

$(document).ready(function(){
    $.ajax({
      type: 'POST',
      url: 'ajax.php',
      data: page,
      // --------------------
      dataType: 'json',
      // --------------------
      beforeSend: alert("Before"),
      success: function(respond){
        // var obj = JSON.parse(respond);
        console.log(respond);
        // for (var i in obj.data)
        // alert("Key = " + i + " --- VALUE = " + obj.data[i]); /* Перебирает слово Array */
      }
    });
  });

$routput = "Bad code!";
$ioutput = "<img src='%s'/>";
$pattern = "/^\[[img|IMG]+=\'(.*).(jpg|png|gif)\'\]\$/";
$allowed = array("image/jpeg", "image/png", "image/gif");
$bbimage = "[IMG='http://www.hdiphonewallpapers.us/phone-wallpapers/phone/12963B64236440-2J38.jpg']";

if (preg_match($pattern, $bbimage)) {
	
	try {
		$path = preg_replace($pattern, "$1.$2", $bbimage);
		$size = getimagesize($path);
		
		$mime = (string) $size['mime'];
		
		if ($mime && in_array($mime, $allowed, true)) {
			$routput = sprintf($ioutput, $path);
		}
		
	} catch (Exception $e) {}
}

echo $routput;