First prototype

src/peoplecounter.py

@@ -0,0 +1,125 @@
+from sensor.tofsensor import ToFSensor, Directions
+from datetime import datetime
+
+
+COUNTING_CB = "counting"
+START_TIME = "start"
+END_TIME = "end"
+
+
+class PeopleCounter ():
+    def __init__(self, sensor: ToFSensor) -> None:
+        self.sensor = sensor
+        self.callbacks = {COUNTING_CB: []}
+        self.maxTriggerDistance = 120   # In cm
+
+    def hookCounting(self, cb) -> None:
+        self.callbacks[COUNTING_CB].append(cb)
+
+    def unhookCounting(self, cb) -> None:
+        self.callbacks[COUNTING_CB].remove(cb)
+
+    def run(self) -> None:
+        self.keepRunning = True
+        direction = Directions.INSIDE
+        self.directionState = {
+            Directions.INSIDE: {
+                START_TIME: None, END_TIME: None
+            },
+            Directions.OUTSIDE: {
+                START_TIME: None, END_TIME: None
+            }
+        }
+
+        while self.keepRunning:
+            # Switch to other direction
+            direction: Directions = Directions.other(direction)
+
+            self.sensor.setDirection(direction)
+
+            distance: float = self.sensor.getDistance()
+            triggered: bool = self.isTriggerDistance(distance)
+            changed: bool = self.updateState(direction, triggered)
+
+            if changed:
+                countChange: int = self.getCountChange(self.directionState)
+                self.handleCallbacks(countChange)
+
+    def getCountChange(self, directionState) -> int:
+        # Is valid?
+        for direction in Directions:
+            if directionState[direction][START_TIME] is None or directionState[direction][END_TIME] is None:
+                return 0    # Return no change if not valid
+
+        # Get times into variables
+        insideStart = directionState[Directions.INSIDE][START_TIME]
+        insideEnd = directionState[Directions.INSIDE][END_TIME]
+        outsideStart = directionState[Directions.OUTSIDE][START_TIME]
+        outsideEnd = directionState[Directions.OUTSIDE][END_TIME]
+
+        # In what direction is the doorframe entered and left?
+        # Entering doorframe in the inside direction
+        enteringInside: bool = outsideStart < insideStart
+        # Leaving dooframe in the inside direction
+        leavingInside: bool = outsideEnd < insideEnd
+
+        # They have to be the same, otherwise they switch directions in between
+        if enteringInside != leavingInside:
+            # Someone did not go all the way
+            # Either
+            # Inside    -######-
+            # Outside   ---##---
+            # or
+            # Inside    ---##---
+            # Outside   -######-
+            return 0
+
+        # Are those times overlapping or disjunct?
+        if insideEnd < outsideStart or outsideEnd < insideStart:
+            # They are disjunct
+            # Either
+            # Inside    -##-----
+            # Outside   -----##-
+            # or
+            # Inside    -----##-
+            # Outside   -##-----
+            return 0
+
+        # What direction is the person taking?
+        if enteringInside:
+            # Entering the inside
+            # Inside    ---####-
+            # Outside   -####---
+            return 1
+        else:
+            # Leaving the inside
+            # Inside    -####---
+            # Outside   ---####-
+            return -1
+
+    def isTriggerDistance(self, distance: float) -> bool:
+        #! TODO: Should be based on the distance from the ground, not them the sensor
+        return distance <= self.maxTriggerDistance
+
+    def handleCallbacks(self, countChange: int) -> None:
+        if countChange == 0:
+            # Do nothing if there is no change
+            return
+
+        for cb in self.callbacks[COUNTING_CB]:
+            cb(countChange)
+
+    def updateState(self, direction: Directions, triggered: bool) -> bool:
+        currentlyTriggered = self.directionState[direction] == None
+
+        if triggered and not currentlyTriggered:
+            # Set as new beginning for this direction
+            self.directionState[direction][START_TIME] = datetime.now()
+            self.directionState[direction][END_TIME] = None
+            return True
+        elif not triggered and currentlyTriggered:
+            # Set as new end for this direction
+            self.directionState[direction][END_TIME] = datetime.now()
+            return True
+
+        return False

src/sensor/tofsensor.py

@@ -1,16 +1,25 @@
 from enum import Enum
 
 
-class Direction(Enum):
-    INDOOR = "indoor"
-    OUTDOOR = "outdoor"
+class Directions(Enum):
+    INSIDE = "indoor"
+    OUTSIDE = "outdoor"
+
+    def other(self, direction: Direction) -> Direction:
+        if direction is Directions.INSIDE:
+            return Directions.OUTSIDE
+        else:
+            return Directions.INSIDE
+
+    def __iter__(self):
+        return [self.INSIDE, self.OUTSIDE]
 
 
 class ToFSensor:
-    def open(self):
+    def open(self) -> None:
         raise NotImplementedError()
 
-    def setDirection(self, direction: Direction):
+    def setDirection(self, direction: Directions) -> None:
         """Configure sensor to pick up the distance in a specific direction.
         """
         raise NotImplementedError()
@@ -19,6 +28,6 @@ class ToFSensor:
         """Returns new distance in cm.
         """
         raise NotImplementedError()
-    
-    def close(self):
+
+    def close(self) -> None:
         raise NotImplementedError()

src/sensor/vl53l1xsensor.py

@@ -1,4 +1,4 @@
-from sensor.tofsensor import Direction, ToFSensor
+from sensor.tofsensor import Directions, ToFSensor
 import VL53L1X
 
 # Reference: https://github.com/pimoroni/vl53l1x-python
@@ -22,7 +22,7 @@ class VL53L1XSensor (TofSensor):
     def __init__(self) -> None:
         super().__init__()
 
-    def open(self):
+    def open(self) -> None:
         self.sensor = VL53L1X.VL53L1X(i2c_bus=1, i2c_address=0x29)
         self.sensor.open()
 
@@ -37,12 +37,13 @@ class VL53L1XSensor (TofSensor):
         # 1 = Short Range
         # 2 = Medium Range
         # 3 = Long Range
-    def setDirection(self, direction: Direction):
+
+    def setDirection(self, direction: Directions) -> None:
         """Configure sensor to pick up the distance in a specific direction.
         """
         direction_roi = {
-            Direction.INDOOR: VL53L1X.VL53L1xUserRoi(6, 3, 9, 0),
-            Direction.OUTDOOR: VL53L1X.VL53L1xUserRoi(6, 15, 9, 12)
+            Directions.INSIDE: VL53L1X.VL53L1xUserRoi(6, 3, 9, 0),
+            Directions.OUTSIDE: VL53L1X.VL53L1xUserRoi(6, 15, 9, 12)
         }
 
         roi = direction_roi[direction]
@@ -58,6 +59,6 @@ class VL53L1XSensor (TofSensor):
 
         return distance / 10
 
-    def close(self):
+    def close(self) -> None:
         self.sensor.stop_ranging()
         self.sensor.close()