That’s because that GstBuffer is simply a descriptor of the NVMM memory handle, and the nvbuf_utils / EGL APIs need to be used to map it into CUDA. These are C/C++ APIs so not accessible from Python - which isn’t a problem for me, because my underlying implementation is in C++ (which gets exposed via my Python extension modules)
Anyhow, I’ve commited the initial changes to gstDecoder here:
I recommend that you re-clone/re-build from source. These changes are only for gstDecoder currently (so receiving RTP/RTSP and reading video files). I am going to refactor this so I can make it work with gstCamera as well. But it will be good to know if it works/improves things for you. I don’t think you should need to make any modification to the command line. After re-building, you should see the pipeline printed out now specifies to use NVMM memory.