I am from NIE Mysore. It was a three day process as it took time to conduct pool campus of 3 colleges all together (NIE Mysore, SJCE Mysore, PES Mandya).
Day 1: Aptitude test conducted by Aspiring Minds which consisted of Quants, Logical Reasoning, English and C/C++ based simple theoretical (non-programming) questions. It was easy. 49 students from my college were shortlisted.
Day 2: GD involving 7 people in a group on any random economic/health/environment issues. You have to show your confidence and positive attitude not only claiming your points but also keep everyone active in the group. 22 were shortlisted from my college.
Day 3: Personal interview. Technical followed by HR interview. technical interview is very easy. No codes and stuff was asked from me. Only technical projects will be asked and may be a technical puzzle. HR also goes smoothly if you are confident and positive enough. 11 got selected from NIE.
I was one among them. :)