Jetson Nano Opencv gStreamer video distortion when show in portrait

Robotics & Edge Computing Jetson & Embedded Systems Jetson Nano
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1

Hi Guy,

I’m doing face recognition using opencv with jetson nano. Camare is pi camera and use gstreamer to capture video.

Everything ok when I display video in landscape, but video become distortion when I rotate video to display in portrait. Below is my code, any suggest? Thank you

def get_jetson_gstreamer_source(capture_width=1280, capture_height=720, display_width=480, display_height=640, framerate=30, flip_method=2):

 return (
         f'nvarguscamerasrc ! video/x-raw(memory:NVMM), ' +
         f'width=(int){capture_width}, height=(int){capture_height}, ' +
         f'format=(string)NV12, framerate=(fraction){framerate}/1 ! ' +
         f'nvvidconv flip-method={flip_method} ! ' +
         f'video/x-raw, width=(int){display_width}, height=(int){display_height}, format=(string)BGRx ! ' +
         'videoconvert ! video/x-raw, format=(string)BGR ! appsink'
         )

cap = cv2.VideoCapture(get_jetson_gstreamer_source(), cv2.CAP_GSTREAMER)
3

Hi,
Please check if the issue is seen in running the sample:

import sys
import cv2

def read_cam():
    cap = cv2.VideoCapture("nvarguscamerasrc ! video/x-raw(memory:NVMM), width=(int)1280, height=(int)720,format=(string)NV12, framerate=(fraction)30/1 ! nvvidconv flip-method=1 ! video/x-raw, format=(string)BGRx ! videoconvert !  appsink")
    if cap.isOpened():
        cv2.namedWindow("demo", cv2.WINDOW_AUTOSIZE)
        while True:
            ret_val, img = cap.read();
            cv2.imshow('demo',img)
            cv2.waitKey(10)
    else:
     print "camera open failed"

    cv2.destroyAllWindows()


if __name__ == '__main__':
    read_cam()

For 90-degree rotation, it should be flip-method=1.

4

Hi,

Thanks for reply and sorry for late response. I set flip method to 2 is because the camera orientation. Now everything ok when I rotate the camera and use flip method to 1.

Thank you.