title: How to add logo on levelplot?
body: <p>I want to make a plot from raster data using <code>levelplot</code>. How to add a header which contains logo.png and title, like showed on this picture?</p>
  
  <p>Here is my data: <a href="https://oceandata.sci.gsfc.nasa.gov/cgi/getfile/A20190012019031.L3m_MO_SST_sst_4km.nc" rel="nofollow noreferrer">SST</a></p>
  
  <p>Here is my basic code to produce this map:</p>
  
  <pre><code>r&lt;-crop(raster(flname, varname="sst"), extent(90, 144, -20, 25))
  
  png('SST.png', height = 2000, width = 2500, res = 300)
  print(levelplot(r, col.regions = sst, at=seq(20, 34, 0.1),
                yscale.components=yscale.raster.subticks,
                xscale.components=xscale.raster.subticks,
                margin=FALSE, ylab='Latitude', xlab='Longitude', 
                main=paste0(flname,' (deg-C)')))
  dev.off()
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/jhBPJ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/jhBPJ.png" alt="enter image description here"></a></p>