The increased workload of the High Efficiency Video Coding (HEVC) and processing of high resolution videos require parallelization of the encoding/decoding process. However, to efficiently utilize the hardware resources and power budgets in a many-core processor, workload balanced parallelization of HEVC encoding is of high importance. Further, minimizing the number of active cores for processing the given HEVC encoding workload is required to decrease the power consumption. In order to address the above challenges, this work presents a HEVC parallelization technique to adaptively determine the Tile partitioning while accounting for the compute capabilities of the underlying processing cores. Afterwards, it determines a mapping of Tiled-HEVC processing on different cores such that the number of compute cores is minimized, and hence reducing the power consumption. Experimental results demonstrate that in addition to reducing the total compute cores, our technique provides up to 14.4% power savings compared to state-of-the-art uniform Tile partitioning approach.