OpenCV Error: Assertion failed (ssize.width > 0 &&

F:\tmp>python genPlate.py 100 ./plate_100
冀JBSLLQ ['冀', 'J', 'B', 'S', 'L', 'L', 'Q']
OpenCV(3.4.1) Error: Assertion failed (ssize.width > 0 && ssize.height > 0) in cv::resize, file D:\Build\OpenCV\opencv-3.4.1\modules\imgproc\src\resize.cpp, line 4044
Traceback (most recent call last):
  File "genPlate.py", line 230, in <module>
    G.genBatch(int(sys.argv[1]),2,range(31,65),sys.argv[2],(272,72))
  File "genPlate.py", line 222, in genBatch
    img = cv2.resize(img,size)
cv2.error: OpenCV(3.4.1) D:\Build\OpenCV\opencv-3.4.1\modules\imgproc\src\resize.cpp:4044: error: (-215) ssize.width > 0 && ssize.height > 0 in function cv::resize


上面是做车牌的程序，命令窗口出的提示是上面，不懂怎么改？求指导