title: Batch Image files - Replace spaces with an underscore in filename
body: <p>I want to go through a folder and replace all the spaces in a filename with an underscore. For example the image "dark green.jpg" would change to "dark_green.jpg". I have hundreds of images that a client uploaded to a site that need to be changed so I would like a way to batch it. </p>
  
  <p>Is there an quick and easy way to do this? It can be in photoshop, bridge or just using some native windows function.</p>