I used Adobe Photoshop, and these are the steps:
1- duplicate the layer of the original photo 2 times, so you have 3 layers of the original photo as a result.
2- apply a "
Gaussian blur" effect for the 2nd layer and set the mode to
overlay
3- apply a "
high pass" effect for the 3rd layer and set the mode to
overlay
4- add an adjustment layer (gradient black to white) on the top, and set the mode to
softlight
5- Done
