Refactor some repeated code

game/detector.py

 import apriltag
 import cv2
 
+from game.webcam_chooser import WebcamWindow
+
 
 class Detector(apriltag.Detector):
     DECISION_MARGIN = 40
 
-    def __init__(self, cam):
+    def __init__(self):
         super().__init__()
-        self.cam = cam
 
     def detect(self, img, return_image=False):
         dets = super().detect(img)
@@ -20,11 +21,11 @@ class Detector(apriltag.Detector):
 
         # Refresh cam before trying to detect tags, else it reads an old image
         for i in range(5):
-            self.cam.read()
+            WebcamWindow.cam.read()
 
         tag_id = None
         while not tag_id:
-            ret, frame = self.cam.read()
+            ret, frame = WebcamWindow.cam.read()
             if not ret:
                 print("Failed to grab frame.")
                 break
@@ -55,6 +56,3 @@ class Detector(apriltag.Detector):
                 pos = det.center.astype(int) + (-10, 10)
                 cv2.putText(img, ident, tuple(pos), cv2.FONT_HERSHEY_SIMPLEX, 1, (0, 0, 255), 2)
         return dets
-
-    def stop_webcam(self):
-        self.cam.release()

game/scoreboard.py

-import cv2
 from socket import *
-from PyQt5 import QtWidgets as qtw
+
 from PyQt5 import QtCore as qtc
 from PyQt5 import QtGui as qtg
-from game.scoreboard_ui import ScoreWindowUi
+from PyQt5 import QtWidgets as qtw
+
 from game.detector import Detector
+from game.scoreboard_ui import ScoreWindowUi
+from game.webcam_chooser import WebcamWindow, frame_to_pixmap
 
 
 class ScoreWindow(ScoreWindowUi):
@@ -13,14 +15,14 @@ class ScoreWindow(ScoreWindowUi):
     PORT = 42563
     MAX_START_SENT = 5
 
-    def __init__(self, teams, cam):
+    def __init__(self, teams):
         super().__init__()
 
         self.teams = teams
         self.initial_time = 0
         self.time_is_red = False
         self.join_started = False
-        self.detector = Detector(cam)
+        self.detector = Detector()
 
         self.socket = socket(AF_INET, SOCK_DGRAM)
         self.socket.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
@@ -94,16 +96,10 @@ class ScoreWindow(ScoreWindowUi):
 
     def refresh_webcam(self, detect_tags=True):
         # Read an image from the webcam and detect the tags it contains
-        ret, frame = self.detector.cam.read()
+        ret, frame = WebcamWindow.cam.read()
         dets = self.detector.show_tags_on_image(frame)
         if ret:
-            frame = cv2.resize(frame, (640, 480))
-            # Convert frame to QImage
-            cv2.cvtColor(frame, cv2.COLOR_RGB2BGR, frame)
-            rows, cols, _ = frame.shape
-            qimage = qtg.QImage(frame.data, cols, rows, qtg.QImage.Format_RGB888)
-            pixmap = qtg.QPixmap()
-            pixmap.convertFromImage(qimage, qtc.Qt.AutoColor)
+            pixmap = frame_to_pixmap(frame)
             self.webcam_label.setPixmap(pixmap)
         else:
             print("Failed to grab frame.")

game/scoreboard_ui.py

-from PyQt5 import QtWidgets as qtw
 from PyQt5 import QtCore as qtc
 from PyQt5 import QtGui as qtg
+from PyQt5 import QtWidgets as qtw
 
 
 class ScoreWindowUi(qtw.QMainWindow):

game/team_chooser.py

 from PyQt5 import QtCore as qtc
 from PyQt5 import QtGui as qtg
+
 from game.detector import Detector
-from game.team_chooser_ui import TeamWindowUi
 from game.team import Team
+from game.team_chooser_ui import TeamWindowUi
 
 
 class TeamWindow(TeamWindowUi):
@@ -16,10 +17,10 @@ class TeamWindow(TeamWindowUi):
         96: "#FE005D", 97: "#FE002A", 98: "#474747", 99: "#8C8C8C", 100: "#643030", 101: "#9A6565", 102: "#BC9F9F"
     }
 
-    def __init__(self, cam):
+    def __init__(self):
         super().__init__()
 
-        self.detector = Detector(cam)
+        self.detector = Detector()
         self.teams = {}  # The keys are the tag ids and the values are the teams
 
         self.add_activities()

game/team_chooser_ui.py

-from PyQt5 import QtWidgets as qtw
 from PyQt5 import QtCore as qtc
 from PyQt5 import QtGui as qtg
+from PyQt5 import QtWidgets as qtw
 
 
 class AlignDelegate(qtw.QStyledItemDelegate):

game/webcam_chooser.py

 import cv2
-from PyQt5 import QtWidgets as qtw
 from PyQt5 import QtCore as qtc
 from PyQt5 import QtGui as qtg
+from PyQt5 import QtWidgets as qtw
 
 
 class WebcamWindow(qtw.QWidget):
     WEBCAM_REFRESH_TIME = 50
+    WEBCAM_SIZE = (640, 480)
+    cam = None
 
     def __init__(self):
         super().__init__()
@@ -31,6 +33,7 @@ class WebcamWindow(qtw.QWidget):
         self.camera_indexes = return_camera_indexes()
         self.current_index = 0
         self.cam = cv2.VideoCapture(self.camera_indexes[0])
+        self.update_cam(self.cam)
 
         self.left_button.clicked.connect(self.show_previous)
         self.right_button.clicked.connect(self.show_next)
@@ -42,13 +45,7 @@ class WebcamWindow(qtw.QWidget):
         # Read an image from the webcam and detect the tags it contains
         ret, frame = self.cam.read()
         if ret:
-            frame = cv2.resize(frame, (640, 480))
-            # Convert frame to QImage
-            cv2.cvtColor(frame, cv2.COLOR_RGB2BGR, frame)
-            rows, cols, _ = frame.shape
-            qimage = qtg.QImage(frame.data, cols, rows, qtg.QImage.Format_RGB888)
-            pixmap = qtg.QPixmap()
-            pixmap.convertFromImage(qimage, qtc.Qt.AutoColor)
+            pixmap = frame_to_pixmap(frame)
             self.webcam_label.setPixmap(pixmap)
         else:
             print("Failed to grab frame.")
@@ -68,8 +65,11 @@ class WebcamWindow(qtw.QWidget):
         self.cam.release()
         new_index = self.camera_indexes[self.current_index]
         self.cam = cv2.VideoCapture(new_index)
-        self.cam.set(cv2.CAP_PROP_FRAME_WIDTH, 640)
-        self. cam.set(cv2.CAP_PROP_FRAME_HEIGHT, 480)
+        self.update_cam(self.cam)
+
+    @classmethod
+    def update_cam(cls, new_cam):
+        cls.cam = new_cam
 
 
 def return_camera_indexes():
@@ -85,3 +85,14 @@ def return_camera_indexes():
         index += 1
         i -= 1
     return arr
+
+
+def frame_to_pixmap(frame):
+    frame = cv2.resize(frame, WebcamWindow.WEBCAM_SIZE)
+    # Convert frame to QImage
+    cv2.cvtColor(frame, cv2.COLOR_RGB2BGR, frame)
+    rows, cols, _ = frame.shape
+    qimage = qtg.QImage(frame.data, cols, rows, qtg.QImage.Format_RGB888)
+    pixmap = qtg.QPixmap()
+    pixmap.convertFromImage(qimage, qtc.Qt.AutoColor)
+    return pixmap

main.py

 import sys
+
 from PyQt5 import QtWidgets as qtw
-from game.team_chooser import TeamWindow
+
 from game.scoreboard import ScoreWindow
+from game.team_chooser import TeamWindow
 from game.webcam_chooser import WebcamWindow
 
 
@@ -11,28 +13,17 @@ class MainWindow(qtw.QWidget):
         self.stacked_layout = qtw.QStackedLayout()
 
         self.webcam_window = WebcamWindow()
+        self.team_window = TeamWindow()
+        self.scoreboard_window = ScoreWindow(self.team_window.teams)
+
         self.stacked_layout.addWidget(self.webcam_window)
+        self.stacked_layout.addWidget(self.team_window)
+        self.stacked_layout.addWidget(self.scoreboard_window)
 
-        # We need to wait for the webcam to be chosen before creating the other windows
         self.webcam_window.start_button.clicked.connect(self.show_team_window)
-
-    def show_team_window(self):
-        self.team_window = TeamWindow(self.webcam_window.cam)
-        self.scoreboard_window = ScoreWindow(self.team_window.teams, self.webcam_window.cam)
-
-        # Add teams to test the application
-        if len(sys.argv) > 1 and sys.argv[1] == "test":
-            for tag_id in w.team_window.team_colors.keys():
-                tag_str = str(tag_id)
-                name = "Test " + str(tag_id)
-                w.team_window.name_input.setText(name)
-                w.team_window.tag_label.setText(tag_str)
-                w.team_window.add_button.click()
-
         self.team_window.start_button.clicked.connect(self.start_activity)
 
-        self.stacked_layout.addWidget(self.team_window)
-        self.stacked_layout.addWidget(self.scoreboard_window)
+    def show_team_window(self):
         self.stacked_layout.setCurrentIndex(1)
 
     def start_activity(self):
@@ -47,4 +38,14 @@ class MainWindow(qtw.QWidget):
 if __name__ == '__main__':
     app = qtw.QApplication(sys.argv)
     w = MainWindow()
+
+    # Add teams to test the application
+    if len(sys.argv) > 1 and sys.argv[1] == "test":
+        for tag_id in w.team_window.team_colors.keys():
+            tag_str = str(tag_id)
+            name = "Test " + str(tag_id)
+            w.team_window.name_input.setText(name)
+            w.team_window.tag_label.setText(tag_str)
+            w.team_window.add_button.click()
+
     sys.exit(app.exec_())