PHP image upload problem

 <div>
     <p><font size="+1" color = 'red'>image must rename as category id & only upload .jpg format </br> max (h-95px / W 165px)  </font></p>
    <label for="img">Image:</label>
<input type="file" name="image" />
    <input type="submit" name="submit" value="submit" />
    </div>

    if(isset($btnadd)){
        $sql = "insert into category (cat_id,cat_name) values (:id,:cname)";
        $stmt = $con ->prepare($sql);
        $stmt->execute(array(':id'=>$id,':cname'=> $cname));


        $result = $stmt->fetch(PDO::FETCH_ASSOC);




    $tmp=$_FILES["file"]["tmp_name"];
  $extension = explode("/", $_FILES["file"]["type"]);
  $name=$id.".".$extension[1];

move_uploaded_file($tmp, "images/" . $id.".".$extension[1]);