Implementation of PyQT display in Multithreaded Python program [duplicate] - python-3.x

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Closed 17 hours ago.
I am testing PyQT display window in multithread python program.
The PyQT display window doesn't display well.
PyQT display is as follow
But when the program runs, the display stops at the following stage
I see full display only when CTRL+C is pressed.
How to improve the program?
The whole code is here
import threading
import time
from threading import Thread
from threading import Event
import signal, os
import sys
from PyQt5.QtWidgets import (QApplication, QWidget, QPushButton, QGridLayout, QLabel)
class CameraStreamingWidget():
def __init__(self, ID):
self.id = ID
self.ready_lock = threading.Lock()
self.ready = False
self.stop_event = Event()
self.get_frame_thread = Thread(target=self.get_frame, args=())
self.get_frame_thread.daemon = True
self.get_frame_thread.start()
self.count = 0
self.before_read = time.time()
print("Camera "+str(ID)+" launched ");
def reset_ready_flag(self):
with self.ready_lock:
self.ready = False
return
def read_ready_flag(self):
ret = False
with self.ready_lock:
ret = self.ready
return ret
def get_frame(self):
while not self.stop_event.is_set():
try:
time.sleep(1)
self.count = self.count + 1
if(self.count >= 4):
cur_time = time.time()
print(f'cam_id {self.id}: {1000*(cur_time - self.before_read):.0f} ms')
with self.ready_lock:
self.ready = True
self.before_read = time.time()
self.count = 0
except AttributeError:
pass
class SIGINT_handler():
def __init__(self):
self.SIGINT_WORKER = False
def signal_handler(self, signal, frame):
print('\nYou pressed Ctrl+C!')
self.SIGINT_WORKER = True
handler = SIGINT_handler()
signal.signal(signal.SIGINT, handler.signal_handler)
class InferenceWidget():
def __init__(self,):
# source params
self.Cameras = []
for id_ in range(4):
cam = CameraStreamingWidget(id_)
self.Cameras.append(cam)
self.stop_event = Event()
self.runinference_thread = Thread(target=self.runinference, args=())
self.runinference_thread.daemon = True
self.runinference_thread.start()
def runinference(self):
#Run
while not self.stop_event.is_set():
#This is for detection
for id_,cam in enumerate(self.Cameras):
if cam.read_ready_flag() == True:
inference_start = time.time()
time.sleep(0.08)
cam.reset_ready_flag()
print(f'Inference time {1000*(time.time() - inference_start):.0f} ms for cam_id {id_}')
if handler.SIGINT_WORKER:
self.stopexecution()
return
def stopexecution(self):
print("Cameras are closed")
self.stop_event.set()
#python spatiotemporal_det_multicam.py
#Display images
class Example(QWidget):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
grid = QGridLayout()
self.setLayout(grid)
names = ['Cls', 'Bck', '', 'Close',
'7', '8', '9', '/',
'4', '5', '6', '*',
'1', '2', '3', '-',
'0', '.', '=', '+',]
positions = [(i, j) for i in range(5) for j in range(4)]
for position, name in zip(positions, names):
if name == '':
continue
button = QPushButton(name)
grid.addWidget(button, *position)
self.setWindowTitle('PyQt window')
self.show()
def main():
app = QApplication(sys.argv)
ex = Example()
inferenceObj = InferenceWidget()
inferenceObj.runinference_thread.join()
print("Thread exit")
sys.exit(app.exec_())
if __name__ == '__main__':
main()