OpenCV image crop didn't work in linux, but works on local – CentOS

def imgCrop(img, src):

    x = 0
    y = 514
    w = 1502
    h = 1170
    cv2.imwrite("test.png",img)
    crop_img = img[y:y+h, x:x+w]
    cv2.imwrite("img.png", crop_img)
imgCrop(img, src)

This is my code, I tried to crop an image then save it, runs well locally.
But when I try to do it on EC2 linux centOs, it just shows

!_img.empty() in function ‘imwrite’

"test.png" is good, but when it reached crop_img, it’s empty.
I’ve tried "pip install opencv-contrib-python" it still don’t work, and saw all related post, still have no clue on this.

Please help! Thank you!