Secure operating regions are utilized by system operators to define system limits and rapidly assess the state of the power grid. Dynamic Security Assessment produces a set of power system limit points that are then used to construct the secure operating region. This data set is typically large for a complex power system, and processing these in a timely manner becomes difficult. In this paper, we propose novel techniques to efficiently automate the computation of the secure operating region. The algorithm reduces the size of the limit point data set and simplifies the operating region constraints while retaining maximal secure operation region. Our algorithm can be used in off-line studies for compressing a large limit point data set with minimal information loss. It can also be applied to on-line studies in which processing efficiency is critical. Our algorithm was applied to identify voltage and transient secure operating regions on a IEEE 39 bus system.