Parallel structures may be used to increase a system processing speed in case of large amount of data or highly complex calculations. Dynamic Voltage and Frequency Scaling (DVFS) may be used for simpler calculations in order to decrease the system voltage or frequency and achieve lower power consumption. Combining these two mechanisms may lead to higher efficiency and lower power consumption. In this paper, we introduce a parallel decoding process with Digital Signal Processing (DSP) for power efficiency in a heterogeneous multi-core embedded system. We describe a parallel low-power design on the system level. Under the condition of preserving the original decoding process, we manage the size of the system's multimedia buffer by considering the spontaneous streaming transfer and tuning the decoding process scheduling time by using the DVFS system in order to decrease the multimedia data dependency and achieve a multi-core embedded system with accurate and low-power detection mechanism.