Can some one please help me in correcting the mistake I'm making in HTML DOM parsing?

I've one sample string as follows :

$feed_status = Nice to see you all back again <img src=\"http://ift.tt/1BZQwnH\" alt=\"Smile\" title=\"Smile\" title=\"v_middle\" /><img src=\"http://ift.tt/1BZQwnH\" alt=\"Smile\" title=\"Smile\" title=\"v_middle\" /><img src=\"http://ift.tt/1BZQwnH\" alt=\"Smile\" title=\"Smile\" title=\"v_middle\" />;

(Forgive me for syntactical errors like placing of single quotes and double quotes)

For your reference I've just added three <img> tags to the string but in real situation this string could contain a single <img> tag or no <img> tag or more than one <img> tags.

I want to get names of files present in each of the <img> tag's src attribute and make array of those file names. Then I have to replace these <img> tags by strings from an array titled $emoticon_codes which is created dynamically based on the file name present in <img> tag. This replacement of strings should happen is the same order.

For this I've tried following code. Till the creation of dynamic array titled $emoticon_codes everything works fine but I'm facing with code for replacing the current <img> tags with the strings from the array $emoticon_codes. So can somebody please help me in correcting the mistake I'm making in my code while replacing the <img> tags from the string.

Following is my code :

  $doc = new DOMDocument();
  $doc->loadHTML($feed_status);
  $imageTags = $doc->getElementsByTagName('img');

  if(count($imageTags)) {
    $emoticon_codes = array();
    foreach($imageTags as $tag) {
      if (basename($tag->getAttribute('src')) == 'evilgrin.png') {
        array_push($emoticon_codes, '\ue404');
      }
      if (basename($tag->getAttribute('src')) == 'grin.png') {
        array_push($emoticon_codes, '\ue415');
      }
      if (basename($tag->getAttribute('src')) == 'happy.png') {
        array_push($emoticon_codes, '\ue057');
      }
      if (basename($tag->getAttribute('src')) == 'smile.png') {
        array_push($emoticon_codes, '\ue056');
      }
      if (basename($tag->getAttribute('src')) == 'surprised.png') {
        array_push($emoticon_codes, '\ue107');
      }
      if (basename($tag->getAttribute('src')) == 'tongue.png') {
        array_push($emoticon_codes, '\ue105');
      }
      if (basename($tag->getAttribute('src')) == 'unhappy.png') {
        array_push($emoticon_codes, '\ue403');
      }
      if (basename($tag->getAttribute('src')) == 'waii.png') {
        array_push($emoticon_codes, '\ue407');
      }
      if (basename($tag->getAttribute('src')) == 'wink.png') {
        array_push($emoticon_codes, '\ue405');
      }
    }
    /*Till here everything works fine. The array $emoticon_codes is also getting generated finely*/

    /*Following is the code giving problem to me,*/
    $t = 0;

    foreach($imageTags as $img) {
      $img->parentNode->replaceChild($img, $doc->createTextNode($emoticon_codes[$t]));
      $t++;
      if ($t > count($emoticon_codes)) {
        break;
      }
    }
  }

My desired output string should be like follows after echo $feed_status; :

$feed_status = Nice to see you all back again \ue056 \ue056 \ue056;

Thanks in advance.