Download GemFX from here: http://www.twcenter.net/forums/showthread.php?672483-A-R2-TW-GEMFX-Version-1-0-9
Once installed in your Dark Souls II "Game" folder navigate to "\GEMFX\Presets\current" and replace the cfg file with the one extracted from here:
1. Chromatic aberration might be too strong or too subtle (arguably a good thing?) depending on your resolution, feel free to play around with the HBO values on the GemFX configurator under the "Additional Shader" tab until you're satisfied with it. (Mostly the setting for Shift Amount).
2. You should probably be using GeDoSaTo for texture replacements and better post-processing effects.(https://redd.it/2g52sj), here are my settings: http://pastebin.com/Yw6y23yy
•Be aware that you can customize hotkeys for enabling and disabling the post processing effects from GeDoSaTo. The asmodean tonemap works well with this preset but it might be too dark for some people.
This is the very preset used in the video, uploaded under request from a friend who was still interested in the regular 2014 version of the game for whatever reason.
If you're seriously going to use this you might as well consider grabbing these great mods: