doing an aura

[aka]

Hi,

I am looking for a mean to transform one of the two first images to the last one.

Please note that :

- The two first images are the same, except the edge of the second (out of focus).
- The choice for the color of the aura, on the third image, is the opposite of the basis color of the image :

Blue <-> Orange
Yellow <-> Purple
Red <-> Green

But this is not mandatory.

Thanks 

[rich2005]

You could try a drop shadow: 
If a hard edge, give it a blur

   

Then a Drop Shadow  X / Y = zero (not 1 as screenshot, my mistake)  Adjust the Blur radius and Grow radius.
Set the Color and Opacity
Open the Blending options and set the mode to Merge and adjust the Blending Opacity.