title: paperjs - How to apply brightness/contrast like effects on the raster image?
body: <p>I have tried to apply the image adjustment options using <code>paper.js</code>, but it will only apply to the <code>fillcolor</code>.</p>
  
  <p>Does anyone know how to apply <em>brightness</em>, <em>contrast</em> or <em>other</em> image adjustments to the raster image?</p>
  
  <p>For example: </p>
  
  <pre><code>var url = 'http://images.com/q.jpg';
  var raster = new paper.Raster(url);
  raster.brightness = .5;
  </code></pre>
  
  <p>Are there any pre-defined functions available for image adjustment in <code>paper.js</code>? </p>