Thank you for you answer!
I am also looking into encoding 4K video at 15 FPS with a i.MX8MP.
However, neither repository seems to reference H265 encoding, only H264?
gstvpuenc.c and mxc_v4l2_vpu_enc.c in particular
Edit: Just answered my own question, H265 is also known as High Efficiency Video Coding (HEVC), which is listed in gstvpuenc.c
(leaving this just in case anyone is confused too...)
Best,
Liliane