title: yii2 Image::thumbnail error: Unable to open image
body: <p>I'm trying to make a thumbnail of an imagen using <code>Image::thumbnail</code> of <code>yii\imagine\Image</code> and I always have the same error: <code>Unable to open image</code>. I've been trying to set full path to achieve it but always raise the same error.</p>
  <p>For example:</p>
  <p><code>Image::thumbnail('&lt;my personal path&gt;/web/uploads/resources/5fd34269ab821.jpg', 400, 400)</code></p>
  <p>I changed the permission of the folder and the image directly, but nothings works. I think that problem can be other. Any sugestion?</p>