Arducam imx477 4k@30fps with jetson nano

i’m using arducam imx477 on jetson nano 4gb developer kit .
on the paper arducam imx477 can capture images in 30 fps on 4k resolution . but i couldn’t reach to 30 fps . in the best result i get 13fps .
i’m using gstream and opencv modules to read data .
this is the dimensions of the image 3280x2464 in 3 color channel ( the resolution is lower than 4k actually)

The performance bottleneck should be in copying data from NVMM buffer to CPU buffer. Please check if you can reach target frame rate by running:

$ gst-launch-1.0 nvarguscamerasrc ! fpsdisplaysink textrlay=0 video-sink=fakesink sync=0 -v

And then try

$ gst-launch-1.0 nvarguscamerasrc ! nvvidconv ! video/x-raw,frmat=BGRx ! videoconvert ! video/x-raw,format=BGR ! fpsdisplaysink text-overlay=0 video-sink=fakesink sync=0 -v

Yes it worked fine and reached 30fps on 4k resolution .
Thank you.
how can i reach this fps in python script??
I really need it.please help me

Please apply the string to this sample and check if it can achieve target frame rate:
OpenCV Video Capture with GStreamer doesn't work on ROS-melodic - #3 by DaneLLL

It takes high CPU usage. Please execute sudo nvpmodel -m 0 and sudo jetson_clocks. To run CPU cores at maximum clock.