Actual maximum bit rate and frame rate will depend on the logic clock frequency and the system bus performance. for imx8mp encoding, which can support h.264 up to 1080p@60 frame rate (40Mbps), for H.265, up to 1920x1080 with 60 frame rate, as I known, the swreg fixed the 1080p as the max resolution, couldn't support 4k, the 60fps we talking about this encoding time/total time(including pipeline run time), if you mean core encoding fps, maybe you can get more than 60fps