You will see this release uses , not the newer x265 (HEVC). In 2015, x265 was in its infancy. However, even today, x264 offers "Better" results for 720p because:
This refers to the Digital Theater Systems audio format. "5.1" means six channels of surround sound (five speakers and one subwoofer), providing a high-fidelity cinematic experience. bahubali 2015 720p bluray x264 hindi dts 51 better