Repa is a powerful library for manipulating high-dimensional arrays in parallel. We will use it to read and edit the pixels of an image.
Install Developer's Image Library (DevIL), a cross-platform image manipulation toolkit. It can be downloaded from http://openil.sourceforge.net/download.php or through
apt-get on Debian systems as follows:
$ sudo apt-get install libdevil-dev
Install the Repa package from cabal for the DevIL toolkit as follows:
$ cabal install repa-devil
Create two images named
image2.png that have the same dimensions, which are shown as follows:
Here comes the ...