title: How to get perticular content from html tag attribute into php
body: <p>i have following html content</p>
  
  <pre><code>&lt;p&gt;Hello World&lt;p&gt;
  &lt;img style="height:175px; width:312px" src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAABVYAAAMACAIAAABAXKuVAAAAA3NCSVQICAjb4U/gAAAgAElEQVR4Xu...."&gt;
  &lt;span style="color:rgb(0, 0, 0)"&gt;Lorem ipsum dolor sit amet, consectetur adipiscing elit. Suspendisse fringilla ipsum vitae fermentum accumsan. Nam pellentesque&lt;/span&gt;
  </code></pre>
  
  <p>Now i want to get text <code>iVBORw0KGgoAAAANSUhEU....</code> contain into <code>&lt;img&gt;</code> tag and from <code>src</code>.</p>
  
  <p>How can i get this specific text from html. </p>