title: unoconv export .xlsx file into image like png
body: <p>I have successfully installed <code>unoconv</code> in my ubuntu 14.04 64 bit.</p>
  
  <p>I want to export the first sheet of an .xlsx file into image like png or jpg.</p>
  
  <p>I tried </p>
  
  <pre><code>unoconv -l &amp; 9998 ## this is to start the python listener
  unoconv -f png abc.xlsx
  </code></pre>
  
  <p>I get the following:</p>
  
  <pre><code>unoconv: UnoException during export phase:
  Unable to store document to file:///var/virtual/abc.png (ErrCode 3088)
  
  Properties: ((com.sun.star.beans.PropertyValue){ Name = (string)"FilterName", Handle = (long)0x0, Value = (any){ (string)"draw_png_Export" }, State = (com.sun.star.beans.PropertyState)DIRECT_VALUE }, (com.sun.star.beans.PropertyValue){ Name = (string)"Overwrite", Handle = (long)0x0, Value = (any){ (boolean)true }, State = (com.sun.star.beans.PropertyState)DIRECT_VALUE }, (com.sun.star.beans.PropertyValue){ Name = (string)"OutputStream", Handle = (long)0x0, Value = (any){ (com.sun.star.uno.XInterface)0x2695ef8{, supportedInterfaces={com.sun.star.io.XOutputStream,com.sun.star.lang.XTypeProvider}} }, State = (com.sun.star.beans.PropertyState)DIRECT_VALUE })
  </code></pre>
  
  <p>What should I do?</p>