import ctypes
import time
import cv2 as cv
import numpy as np

mylib = ctypes.cdll.LoadLibrary("./libtestpythoncpp.so")


char_arr100 = ctypes.c_char*10000000
y = char_arr100()

def showpic():
    str="hello"
    i = 0;
    mylib.registelisten("usbpic");
    nlenx = ctypes.c_int*2
    nlen = nlenx()
    while i< 10000:
	nRtn = mylib.GetData(y,nlen);
        if(nRtn>0):
		xdata = np.frombuffer(y,count = nlen[0])
		matx = cv.imdecode(xdata, cv.IMREAD_COLOR );
		cv.imshow("showing",matx)
		cv.waitKey(1)
		print(nRtn)
	time.sleep(0.001);
    str="exit"
    print(str);


if __name__ == "__main__":
    print ('This is main ,for show pic from c++')
    showpic()