This technique is explained in a very formal way in the paper:Poisson Image Editing (Patrick Perez et al. Microsoft Research UK)

A really nice and understandable tutorial on the maths behind this is : https://www.youtube.com/watch?v=UcTJDamstdk

The main goal of this implementation is to seamlessly blend a piece of an image to another image. Of course the first thing we notice is that we cannot do worse than just cropping and pasting the two images.

So a first nice improvement is to solve Poisson equations on the boundary conditions without considering the gradients inside the destination area. The classic example for this algorithm is to copy and paste the eye in the middle of the hand (this is actually me :) very creepy LOL).

The second improvement is to consider the gradients inside the destination area so that we won't blur the edges.

Other results are available in the results folder!

I tried to keep the implementations of the different versions of the algorithm separate so that the improvements are more understandable.

To execute the code just run either: 1.poissonImageEditing.m 2.poissonImageEditing_MixingGradients.m

The first thing to do when executing the code is to select the region in the source image that we want to copy, and then, using the directional keys, select the area in the target image where we want to paste.