I encoded a cropped video with Staxrip with NVENC H265 CUDA settings (and with nvencc64.exe command line, too, with native NVENC settings), and when I play it back on PC there is no problem.
But when I try to play it back on my media player, there is a black bold line at the bottom of the video and after that all NVENC encoded videos has a black border (even the Open Matte movies, the image also becomes smaller because of this border) like it would cause some kind of "windowed mode". Only a reboot solve this.
I'm not sure but I think the crop causes it (I tried command line crop and .avs script crop as well), because when I encoded videos without cropping, there wasn't any problem with them, or at least I didn't saw any black lines.
I tried with a 4:3 video, too, I cropped the black areas from its sides, and there is the black line at the right of the image when I play it back, and after that the same effect, the black border around other NVENC encoded movies.
On the PC there is no problem at all (in MPC-HC, and I just tried in VLC, too), only on my media player, which is an Eminent EM7680 4K TV Streamer (CPU: AArch64 Processor rev 4 (aarch64), Hardware: Amlogic, Revision 020a, GPU: Mali-450 MP) with the newest LibreELEC (8.2.1 kernel: Linux 3.14.29) and Kodi 17.6 (Git: a9a7a20). There is no option to upgrade only the Kodi to 18, so I can't test with that version.
I uploaded a few minutes of the video:
I don't really know if this a bug or NVENC isn't fully supported?
Thanks in advance!