带有php变量的图像src不会在网页上显示图像

I wrote a code which is retrive image paths and display on the website in bootstrap grid style.But it does not showing the image. Code is working fine, Please help me. here is my code

<div class="row">
<?while ($row = mysql_fetch_assoc($query)) {?>
<div class = "col-md-3">
  <?php echo $row['keywords'];?>
  <?php $imagePath = $row['video_url'];?>
  <?php echo $imagePath;?>
  <div id="video_thumbnail">
      <a href="#" class="thumbnail">
        <?php echo '<img src="' . $imagePath . '">'; ?>
        <img src="<?php echo file_dir . '/' . $imagePath; ?>" height="100" width="100"/>
      </a>
  </div>
</div>
<?php } ?>
</div>

unless file_dir is a constant using DEFINE, I suspect it's because you didn't put a $ in front of it $file_dir

You are also displaying two files. One with the file path and one without.

Chances are, the mysql query is returning a path which is not linked .... ie <image src="myImage.jpg" /> is not the same as <image src="images/myImage.jpg" />

As @pmahomme said, right click the element and check the pat and if need be add the additional requirements