How to replicate libcamera-still with gstreamer pipeline?

Question

My goal is to use gstreamer pipeline instead of libcamera-still. The problem is that the frames generated by the gstreamer pipeline look concave.

Gstreamer Pipeline

def gstreamer_pipeline(
    # Issue: the sensor format used by Raspberry Pi 4B and NVIDIA Jetson Nano B01 are different
    # in Raspberry Pi 4B, this command
    # $ libcamera-still --width 1280 --height 1280 --mode 1280:1280
    # uses sensor format 2328x1748.
    # However, v4l2-ctl --list-formats-ext do not have such format.
    sensor_id=0,
    capture_width=1920,
    capture_height=1080,
    display_width=640,
    display_height=360,
    framerate=21,
    flip_method=0,
):
    return (
        "nvarguscamerasrc sensor-id=%d ! "
        "video/x-raw(memory:NVMM),format=(string)NV12,framerate=(fraction)%d/1 ! "
        "nvvidconv flip-method=%d ! "
        "video/x-raw,width=(int)%d,height=(int)%d,format=(string)BGRx ! "
        "videoconvert ! "
        "video/x-raw,format=(string)BGR ! "
        "appsink"
        % (
            sensor_id,
            framerate,
            flip_method,
            display_width,
            display_height
        )
    )

The result with gstreamer pipeline

The code I run to take frame

libcamera-still -t 5000 --width 1280 --height 1280 --mode 1280:1280 --autofocus-on-capture -o test.jpg

The result with libcamera-still