ok, can I compile ffmpeg from source?
I compiled ffmpeg with this link(Jetson TX2 and FFmpeg - Can't initialize nvrm channel - #5 by DaneLLL), but when I coded h264 with ffmpeg -c:v h264_v4l2m2m I got this error:
[h264_v4l2m2m @ 0x5586dd2fd0] Could not find a valid device
[h264_v4l2m2m @ 0x5586dd2fd0] can't configure encoder