title: Negative lookbehind or something else?
body: <p>The following pattern will capture file names which has suffix and specified extension.
  <code>'/(.+?)(@2x|~ipad|@2x~ipad)\.(jpg|png)/mi'</code></p>
  
  <p>This is example list of files</p>
  
  <pre><code>SLN0098H@2x.JPG
  SLN0098H~ipad.JPG
  SLN0098H_thumb@2x~ipad.JPG
  SLN0098H_thumb@2x.JPG
  SLN0098H_thumb~ipad.JPG
  SLN0099H@2x~ipad.JPG
  SLN0099H@2x.JPG
  SLN0099H~ipad.JPG
  SLN0098H_t@2x.JPG
  SLN0098H_cover@2x.JPG
  </code></pre>
  
  <p>However, I want to exclude those <strong>lines</strong>, which contains <code>_cover</code>, <code>_thumb</code>, <code>_t</code>, <code>_c</code> before file name resolution suffix. Is it possible to do within regex or do I have to loop&amp;filter manually?</p>