Added ability to reopen the same camera multiple times.

displayarray/frame/frame_publishing.py

@@ -147,7 +147,6 @@ def pub_cam_loop_opencv(
     sub = subscriber_dictionary.cam_cmd_sub(name)
     sub.return_on_no_data = ""
     msg = ""
-
     if mjpg:
         try:
             cam.set(cv2.CAP_PROP_FOURCC, cv2.CAP_OPENCV_MJPEG)
@@ -158,6 +157,7 @@ def pub_cam_loop_opencv(
     cam.set(cv2.CAP_PROP_FRAME_HEIGHT, request_size[1])
 
     if not cam.isOpened():
+        print("camera failed to open")
         subscriber_dictionary.CV_CAMS_DICT[name].status_pub.publish("failed")
         return False
     now = time.time()
@@ -168,13 +168,18 @@ def pub_cam_loop_opencv(
         if ret is False or not isinstance(frame, (np.ndarray, list)):
             cam.release()
             subscriber_dictionary.CV_CAMS_DICT[name].status_pub.publish("failed")
+            print("cam returned false")
             return False
         if cam.get(cv2.CAP_PROP_FRAME_COUNT) > 0:
             frame_counter += 1
             if frame_counter >= cam.get(cv2.CAP_PROP_FRAME_COUNT):
                 frame_counter = 0
                 cam = cv2.VideoCapture(cam_id)
-        subscriber_dictionary.CV_CAMS_DICT[name].frame_pub.publish(frame)
+        try:
+            subscriber_dictionary.CV_CAMS_DICT[name].frame_pub.publish(frame)
+        except KeyError:  # we got deleted. Time to exit.
+            cam.release()
+            return False
         msg = sub.get()
     sub.release()
 
@@ -195,9 +200,10 @@ def pub_cam_thread(
     """Run pub_cam_loop in a new thread. Starts on creation."""
 
     name = uid_for_source(cam_id)
+    t = None
     if name in uid_dict.keys():
         t = uid_dict[name]
-    else:
+    if t is None or not t.is_alive():  # Enables reopening cameras
         if "cv" in force_backend.lower():
             pub_cam_loop = pub_cam_loop_opencv
         elif (

displayarray/frame/subscriber_dictionary.py

@@ -50,6 +50,11 @@ def stop_cam(cam_id: Union[int, str]):
     if str(cam_id) in CV_CAM_HANDLERS_DICT:
         CV_CAM_HANDLERS_DICT[str(cam_id)].cmd_pub.publish("quit", blocking=True)
 
+def del_cam(cam_id: Union[int, str]):
+    if str(cam_id) in CV_CAMS_DICT:
+        del CV_CAMS_DICT[str(cam_id)]
+    if str(cam_id) in CV_CAM_HANDLERS_DICT:
+        del CV_CAM_HANDLERS_DICT[str(cam_id)]
 
 def cam_cmd_sub(cam_id, blocking=True):
     """Get a command subscriber for registered camera "cam_id"."""

displayarray/window/subscriber_windows.py

@@ -112,6 +112,7 @@ class SubscriberWindows(object):
     def __stop_all_cams(self):
         for c in self.source_names:
             subscriber_dictionary.stop_cam(c)
+            subscriber_dictionary.del_cam(c)
 
     def handle_keys(self, key_input: int):
         """Capture key input for the escape function and passing to key control subscriber threads."""
@@ -214,7 +215,6 @@ class SubscriberWindows(object):
     def update_frames(self):
         """Update the windows with the newest data for all frames."""
         self.frames = {}
-
         for i in range(len(self.input_vid_global_names)):
             if self.input_vid_global_names[i] in self.FRAME_DICT and not isinstance(
                 self.FRAME_DICT[self.input_vid_global_names[i]], NoData