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	cam = cv2.VideoCapture(0)
        while(True):
            	ret_val, img = cam.read()
            	cv2.imshow('LB', img)
            	if cv2.waitKey(1) == 27:
                	break
        cv2.destroyAllWindows()

Code: Alles auswählen

#!/usr/bin/env python3
import sys
from contextlib import closing
from functools import partial

from PyQt5.QtCore import QTimer
from PyQt5.QtGui import QImage, QPixmap
from PyQt5.QtWidgets import QApplication
from PyQt5.uic import loadUi
import cv2

VIDEO_SOURCE = 0

def iter_frames(video_source):
    video = cv2.VideoCapture(video_source)
    if not video.isOpened():
        raise IOError(f'video source {video_source!r} could not be opened')
    try:
        while True:
            is_ok, frame = video.read()
            if not is_ok:
                break
            yield frame
    finally:
        video.release()


def image_from_frame(frame):
    assert frame.itemsize == 1
    height, width, bytes_per_color = frame.shape
    assert bytes_per_color == 3
    return QImage(
        frame.data, width, height, frame.strides[0], QImage.Format_RGB888
    ).rgbSwapped()


def display_next_image(timer, label, images):
    try:
        image = next(images)
    except (StopIteration, IOError):
        timer.stop()
    else:
        label.setPixmap(QPixmap.fromImage(image))


def main():
    application = QApplication(sys.argv)
    
    ui = loadUi('test.ui')
    ui.exit_button.clicked.connect(ui.close)

    with closing(iter_frames(VIDEO_SOURCE)) as frames:
        timer = QTimer(ui)
        timer.timeout.connect(
            partial(
                display_next_image,
                timer,
                ui.image_label,
                map(image_from_frame, frames),
            )
        )
        timer.start(50)
        ui.show()
        
        sys.exit(application.exec_())


if __name__ == '__main__':
    main()

Code: Alles auswählen

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>Form</class>
 <widget class="QWidget" name="Form">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>400</width>
    <height>300</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>Cam</string>
  </property>
  <layout class="QVBoxLayout" name="verticalLayout">
   <item>
    <widget class="QLabel" name="image_label"/>
   </item>
   <item>
    <widget class="QPushButton" name="exit_button">
     <property name="text">
      <string>Stop</string>
     </property>
     <property name="checkable">
      <bool>false</bool>
     </property>
     <property name="checked">
      <bool>false</bool>
     </property>
    </widget>
   </item>
  </layout>
 </widget>
 <resources/>
 <connections/>
</ui>