We propose a phase step estimation algorithm in a two-step phase shifting interferometry setup based on orientation selective adaptive monogenic filtering (AMF). Initially, the AMF algorithm is used for the fringe pattern normalization. A minor modification in the same algorithm performs an orientation selective monogenic filtering which is capable of providing a reliable estimation of phase step. Due to the use of the same algorithm for normalization and phase step estimation, the proposed method offers computational efficiency and simplicity. Simulation and experimental results are provided to demonstrate the suitability of the proposed method in phase demodulation.