Add server for camera nodes.

DecisionSystem/CentralisedDecision/cameraserver.py

@@ -0,0 +1,106 @@
+from DecisionSystem.CentralisedDecision.ballotvoter import BallotVoter
+from DecisionSystem.CentralisedDecision.messenger import MqttMessenger
+import numpy as np
+import cv2
+import time
+import argparse
+import os.path
+import sys
+from GestureRecognition.simplehandrecogniser import SimpleHandRecogniser
+from threading import Thread
+from queue import Queue
+
+parser = argparse.ArgumentParser(description="Runs a file with OpenCV and gets consensus from the swarm.")
+
+parser.add_argument('-V', '--video', help="Path to video file.")
+
+args = parser.parse_args()
+
+recogniser = SimpleHandRecogniser(None)
+
+# Checks if video file is specified and if that file exists.
+if(args.video):
+    print('finding video')
+    if not os.path.isfile(args.video):
+        print("Input video file ", args.video, " doesn't exist")
+        sys.exit(1)
+else:
+    # Exit if no video file specified - we aren't using webcam here.
+    sys.exit(1)
+
+class VideoGet:
+    '''
+    Code taken from Najam R Syed, available here:
+    https://github.com/nrsyed/computer-vision/tree/master/multithread
+    '''
+    def __init__(self, q, src):
+        '''
+        Must provide a source so we don't accidently start camera at work.
+        '''
+        self._stream = cv2.VideoCapture(src)
+        (self.grabbed, self.frame) = self._stream.read()
+        self.stopped = False
+        self.q = q
+        self.q.put(np.copy(self.frame))
+        self.src = src
+
+    def start(self):    
+        Thread(target=self.get, args=()).start()
+        return self
+
+    def get(self):
+        while not self.stopped:
+            if not self.grabbed:
+                # self.stopped = True
+                print('frame not grabbed')
+                self._stream.release()
+                self._stream = cv2.VideoCapture(self.src)
+                # time.sleep(2)
+                self.grabbed, self.frame = self._stream.read()
+            else:
+                (self.grabbed, self.frame) = self._stream.read()
+                if self.q.full():
+                    self.q.get()
+                self.q.put(np.copy(self.frame))
+                time.sleep(0.03)
+                # Start a new feed.
+            
+    def stop(self):
+        self.stopped = True
+
+def on_vote():
+    # Get the current frame of the camera and process what hand 
+    # is currently being seen. 
+    print('getting frame')
+    # Need to copy rather than just take a reference, as frame will
+    # constantly be changing.
+    global vd
+    recogniser.setFrame(np.copy(vd.frame))
+    print('Got frame, voting with recogniser')
+    return recogniser.get_gesture()
+
+mqtt = MqttMessenger()
+v = BallotVoter(on_vote, mqtt)
+mqtt.connect()
+
+# Start the video capture at the next whole minute.
+# current_time_sec = time.gmtime(time.time()).tm_sec
+# if current_time_sec < 40:
+#     time.sleep(60 - current_time_sec)
+# else:
+#     time.sleep(60 - current_time_sec + 60)
+print('loading video')
+
+q = Queue(5)
+vd = VideoGet(q, args.video)
+vd.start()
+
+stay_alive = input("Press q to stop, anything else to see what the camera is seeing.")
+
+while stay_alive:
+    if vd.frame is None:
+        continue
+    frame = np.copy(vd.frame)
+    cv2.imshow('Frame', frame)
+    cv2.waitKey(1) & 0xFF
+    stay_alive = input("Press q to stop, anything else to see what the camera is seeing.")