为什么在这种情况下我不能使用QRunnable对象？

问题描述

我正在使用PyQt框架创建一个GUI，该GUI将同时显示两个摄像头（通过USB连接）的提要。到目前为止，我仅在GUI窗口中显示一台摄像机，我的代码可以总结如下：

from PyQt5 import QtWidgets,QtGui
from PyQt5.QtCore import pyqtSignal,pyqtSlot,Qt,QThread,QRunnable,QThreadPool
import sys
import cv2
import numpy as np

class CameraThread(QRunnable):
    '''
    Thread that will read the output from a given camera and emit signal containing the image data 
    and the camera it comes from
    '''
    ## the int in this signal indicates the camID,once more than one cam is instantiated
    change_pixmap_signal = pyqtSignal(int,np.ndarray)
    
    def __init__(self,camID):
        super().__init__()
        self.camID = camID
        
    def run(self):
        cam = cv2.VideoCapture(self.camID)
        while True:
            ret,cv_img = cam.read()
            if ret:
                self.change_pixmap_signal.emit(self.camID,cv_img)

class MainWindow(QtWidgets.QMainWindow):
    
    def __init__(self):
        super().__init__()
        self.initUI()

    def initUI(self):
        ## general window stuff
        self.setwindowTitle('Cam Feeds')
        self.setGeometry(500,50,900,900)

        self.cam_display_w = 400
        self.cam_display_h = 400
        
        self.camC_lab = QtWidgets.QLabel('camC')
        self.camC_lab.setAlignment(Qt.AlignCenter)
        self.camC_lab.resize(self.cam_display_w,self.cam_display_h)
        self.camC_lab.setStyleSheet('QLabel {background-color: rgb(50,200,100)}')

        self.setCentralWidget(self.camC_lab)
        
        self.show()
          
        ## Setting up the camera threads
        self.camC_thread = CameraThread(1)
        self.camC_thread.change_pixmap_signal.connect(self.update_image)
        
        ## Setting up threadpool
        self.threadpool = QThreadPool()
        self.threadpool.start(self.camC_thread)
        
    @pyqtSlot(int,np.ndarray)
    def update_image(self,camID,cv_img):
        '''
        updates the images displayed in each camera label
        '''
        qt_img = self.convert_cv_qt(cv_img)
        self.camC_lab.setpixmap(qt_img)

            
    def convert_cv_qt(self,cv_img):
        ''' convert from opencv image to Qpixmap (without saving to a physical .png file') '''
        rgb_image = cv2.cvtColor(cv_img,cv2.COLOR_BGR2RGB)
        h,w,ch = rgb_image.shape
        bytes_per_line = ch * w
        convert_to_Qt_format = QtGui.QImage(rgb_image.data,h,bytes_per_line,QtGui.QImage.Format_RGB888)
        p = convert_to_Qt_format.scaled(self.cam_display_w,self.cam_display_h,Qt.KeepAspectRatio)
        return QtGui.Qpixmap.fromImage(p)            


def main():
    app = QtWidgets.QApplication(sys.argv)
    a = MainWindow()
    sys.exit(app.exec_())
        
if __name__ == '__main__':
    main()

运行此代码时，出现以下错误：

File "C:/Users/henry/Desktop/main_take1.py",line 105,in initUI
    self.camC_thread.change_pixmap_signal.connect(self.update_image)

TypeError: CameraThread cannot be converted to PyQt5.QtCore.QObject in this context

请有人可以向我解释此错误消息！

理想情况下，我会创建继承QRunnables的CameraThread对象，因此允许使用QThreadPool来管理并行线程的执行，但是出现上述TypeError ...

我尝试将CameraThread类的父级切换到QThread，并且可以正常工作，但是我期望一旦连接第二台摄像机（同时显示），我就需要管理顺序/优先级我自己执行两个CameraThread实例的过程，我宁愿不这样做。

您有什么建议？是否有任何类似QThreadPool的多线程工具采用QThreads？还是我可以坚持使用QRunnables？ halp plz x

解决方法

暂无找到可以解决该程序问题的有效方法，小编努力寻找整理中！

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pyqt5 python qthread