[FFmpeg-user] Ffmpeg Nvenc GPU decode , set hwaccel_device not work

[dd]

Dear my friend,
We replace cpu with gpu to ffmpeg recently, I set the gpu device no, but it still use default device 0.
As the following problem Code:
ffmpeg -hwaccel_device 2 -hwaccel cuvid -i a.mp4 -vf “scale=1080:720,overlay=()” -c:v h264_nvenc out.mp4


I found if use “scale_npp” replace  “scale” will work with device 2, but in that way, we will lost some filter functions
like overlay,suntitles burning,and so on.Is there some parameters of scale_npp with the same functions?
Or how can I implement add water picture on gpu platform with seted device number?
Linux server has 5 NVIDIA card, i see it use device 0 always by the nvidia-smi tool.
Hope your help, thank you!