Crear una aplicación de cámara usando Pyqt5

Python3

# importing required libraries
from PyQt5.QtWidgets import *
from PyQt5.QtMultimedia import *
from PyQt5.QtMultimediaWidgets import *
import os
import sys
import time
  
# Main window class
class MainWindow(QMainWindow):
  
    # constructor
    def __init__(self):
        super().__init__()
  
        # setting geometry
        self.setGeometry(100, 100,
                         800, 600)
  
        # setting style sheet
        self.setStyleSheet("background : lightgrey;")
  
        # getting available cameras
        self.available_cameras = QCameraInfo.availableCameras()
  
        # if no camera found
        if not self.available_cameras:
            # exit the code
            sys.exit()
  
        # creating a status bar
        self.status = QStatusBar()
  
        # setting style sheet to the status bar
        self.status.setStyleSheet("background : white;")
  
        # adding status bar to the main window
        self.setStatusBar(self.status)
  
        # path to save
        self.save_path = ""
  
        # creating a QCameraViewfinder object
        self.viewfinder = QCameraViewfinder()
  
        # showing this viewfinder
        self.viewfinder.show()
  
        # making it central widget of main window
        self.setCentralWidget(self.viewfinder)
  
        # Set the default camera.
        self.select_camera(0)
  
        # creating a tool bar
        toolbar = QToolBar("Camera Tool Bar")
  
        # adding tool bar to main window
        self.addToolBar(toolbar)
  
        # creating a photo action to take photo
        click_action = QAction("Click photo", self)
  
        # adding status tip to the photo action
        click_action.setStatusTip("This will capture picture")
  
        # adding tool tip
        click_action.setToolTip("Capture picture")
  
  
        # adding action to it
        # calling take_photo method
        click_action.triggered.connect(self.click_photo)
  
        # adding this to the tool bar
        toolbar.addAction(click_action)
  
        # similarly creating action for changing save folder
        change_folder_action = QAction("Change save location",
                                       self)
  
        # adding status tip
        change_folder_action.setStatusTip("Change folder where picture will be saved saved.")
  
        # adding tool tip to it
        change_folder_action.setToolTip("Change save location")
  
        # setting calling method to the change folder action
        # when triggered signal is emitted
        change_folder_action.triggered.connect(self.change_folder)
  
        # adding this to the tool bar
        toolbar.addAction(change_folder_action)
  
  
        # creating a combo box for selecting camera
        camera_selector = QComboBox()
  
        # adding status tip to it
        camera_selector.setStatusTip("Choose camera to take pictures")
  
        # adding tool tip to it
        camera_selector.setToolTip("Select Camera")
        camera_selector.setToolTipDuration(2500)
  
        # adding items to the combo box
        camera_selector.addItems([camera.description()
                                  for camera in self.available_cameras])
  
        # adding action to the combo box
        # calling the select camera method
        camera_selector.currentIndexChanged.connect(self.select_camera)
  
        # adding this to tool bar
        toolbar.addWidget(camera_selector)
  
        # setting tool bar stylesheet
        toolbar.setStyleSheet("background : white;")
  
  
  
        # setting window title
        self.setWindowTitle("PyQt5 Cam")
  
        # showing the main window
        self.show()
  
    # method to select camera
    def select_camera(self, i):
  
        # getting the selected camera
        self.camera = QCamera(self.available_cameras[i])
  
        # setting view finder to the camera
        self.camera.setViewfinder(self.viewfinder)
  
        # setting capture mode to the camera
        self.camera.setCaptureMode(QCamera.CaptureStillImage)
  
        # if any error occur show the alert
        self.camera.error.connect(lambda: self.alert(self.camera.errorString()))
  
        # start the camera
        self.camera.start()
  
        # creating a QCameraImageCapture object
        self.capture = QCameraImageCapture(self.camera)
  
        # showing alert if error occur
        self.capture.error.connect(lambda error_msg, error,
                                   msg: self.alert(msg))
  
        # when image captured showing message
        self.capture.imageCaptured.connect(lambda d,
                                           i: self.status.showMessage("Image captured : " 
                                                                      + str(self.save_seq)))
  
        # getting current camera name
        self.current_camera_name = self.available_cameras[i].description()
  
        # initial save sequence
        self.save_seq = 0
  
    # method to take photo
    def click_photo(self):
  
        # time stamp
        timestamp = time.strftime("%d-%b-%Y-%H_%M_%S")
  
        # capture the image and save it on the save path
        self.capture.capture(os.path.join(self.save_path, 
                                          "%s-%04d-%s.jpg" % (
            self.current_camera_name,
            self.save_seq,
            timestamp
        )))
  
        # increment the sequence
        self.save_seq += 1
  
    # change folder method
    def change_folder(self):
  
        # open the dialog to select path
        path = QFileDialog.getExistingDirectory(self, 
                                                "Picture Location", "")
  
        # if path is selected
        if path:
  
            # update the path
            self.save_path = path
  
            # update the sequence
            self.save_seq = 0
  
    # method for alerts
    def alert(self, msg):
  
        # error message
        error = QErrorMessage(self)
  
        # setting text to the error message
        error.showMessage(msg)
  
# Driver code
if __name__ == "__main__" :
    
  # create pyqt5 app
  App = QApplication(sys.argv)
  
  # create the instance of our Window
  window = MainWindow()
  
  # start the app
  sys.exit(App.exec())