High dynamic range (HDR) technology has become a new trend of the development of digital microscopes. Currently, due to the high computational complexity, the HDR video cannot be processed and displayed in real-time. Based on REC.2020 high definition (HD) standard, it is feasible and stable to generate the HDR video flow in real-time using GPU accelerated processing. The experimental results show that the presented algorithm not only provides a stable real-time HDR video flow, but also improves the performance of the recovered video in both detail and color, which has overcome the limitation in processing speed and quality of the traditional HDR imaging technology.