Trying to iterate array of objects PHP

I have a method in which I want to parse input from an SQL-Row into an object:

function buildPictureArray($sqlRow) {
   $pics = [];
   foreach($sqlRow as $value) {
      extract($value); // How to do this more elegant?
      $newObj = new PICObject($id, $filename, $thumb . $filename, $full . $filename, $title, $subtitle); // These are column names I got from extract
      $pics[] = $newObj;
   }
   return $pics;
}

My PICObject looks like this:

  Class PICObject {
    public $id;
    public $fileName;
    public $thumbLink;
    public $fullLink;
    public $title;
    public $subTitle;

    function __construct($id, $fileName, $thumbLink, $fullLink, $title, $subTitle) {
      $this->$id = $id;
      $this->$fileName = $fileName;
      $this->$thumbLink = $thumbLink;
      $this->$fullLink = $fullLink;
      $this->$title = $title;
      $this->$subTitle = $subTitle;
    }
  }

Now ideally I want to iterate this $pics array which should now contain several PICObjects and be able to access its fields:

foreach($pics as $picObj) {
   echo $picObj->$fileName;
}

However, this doesn't work. So how to do this? (I've tried it several ways but nothing really did what I was looking for)