Sorry, I didn&#x27;t mean to say &quot;bogus algorithm&quot;.  What I wanted to say is that the results look equivalent as those that can be obtained by linear filtering and rescaling the input image (a standard retinex-like technique):  Compute minus the laplacian of the image, smooth the result using a cauchy kernel, linearly adjust the dynamic range.  You can see the interior of the light bulb and the texture of the wall at the same time.<p>I teach image processing, this is a standard exercice.