[Fix] : Handle Busy Camera on Windows

examples/simple_example_v2.py

@@ -26,7 +26,14 @@
 from eyeGestures import EyeGestures_v2
 
 gestures = EyeGestures_v2()
-cap = VideoCapture(0)
+
+try:
+    cap = VideoCapture(0)
+except RuntimeError as e:
+    print(f"Camera Initialization failed : {e}")
+    pygame.quit()
+    cv2.destroyAllWindows()
+    sys.exit()
 
 x = np.arange(0, 1.1, 0.2)
 y = np.arange(0, 1.1, 0.2)

examples/simple_example_v2_fast.py

@@ -26,7 +26,13 @@
 from eyeGestures import EyeGestures_v2
 
 gestures = EyeGestures_v2()
-cap = VideoCapture(0)
+try:
+    cap = VideoCapture(0)
+except RuntimeError as e:
+    print(f"Camera Initialization failed : {e}")
+    pygame.quit()
+    cv2.destroyAllWindows()
+    sys.exit()
 
 x = np.arange(0, 1.1, 0.5)
 y = np.arange(0, 1.1, 0.5)

examples/simple_example_v3.py

@@ -26,7 +26,13 @@
 from eyeGestures import EyeGestures_v3
 
 gestures = EyeGestures_v3()
-cap = VideoCapture(0)
+try:
+    cap = VideoCapture(0)
+except RuntimeError as e:
+    print(f"Camera Initialization failed : {e}")
+    pygame.quit()
+    cv2.destroyAllWindows()
+    sys.exit()
 
 x = np.arange(0, 1.1, 0.2)
 y = np.arange(0, 1.1, 0.2)

examples/troubleshooting_camera.py

@@ -18,7 +18,13 @@
 
 from eyeGestures.utils import VideoCapture
 
-cap = VideoCapture(0)
+try:
+    cap = VideoCapture(0)
+except RuntimeError as e:
+    print(f"Camera Initialization failed : {e}")
+    pygame.quit()
+    cv2.destroyAllWindows()
+    sys.exit()
 
 x = np.arange(0, 1.1, 0.2)
 y = np.arange(0, 1.1, 0.2)

eyeGestures/utils.py

@@ -2,7 +2,10 @@
 import platform
 import queue
 import threading
+import sys
 import time
+import traceback
+from string import capwords
 
 import cv2
 import numpy as np
@@ -181,36 +184,71 @@ def __init__(self, name, bufforless=True):
 
         if self.stream:
             self.prev_frame = None
-
             self.__openCam(name)
-
             self.q = queue.Queue()
-            self.t = threading.Thread(target=self.__reader)
+            self.t = threading.Thread(target=self.__reader, daemon = True)
             self.t.start()
         else:
             self.frames = []
             with open(name, "rb") as file:
                 self.frames = pickle.load(file)
 
     def __openCam(self, name):
-        if isinstance(name, int):
-            if "Windows" in platform.system():
-                self.cap = cv2.VideoCapture(name, cv2.CAP_DSHOW)
-            else:
-                self.cap = cv2.VideoCapture(name)
+        max_index = 10
 
-            if self.cap is None or not self.cap.isOpened():
-                print(f"Was unable to open camera: {name}.")
-                print(f"Trying to open camera: {name}.")
-                if name + 1 < 10:
-                    self.__openCam(name + 1)
+        if isinstance(name, int):
+            for cam_index in range(name, max_index):
+                if "Windows" in platform.system():
+                    cap = cv2.VideoCapture(cam_index, cv2.CAP_DSHOW)
+                else:
+                    cap = cv2.VideoCapture(cam_index)
+
+                if cap is None or not cap.isOpened():
+                    print(f"Was unable to open camera: {name}.")
+                    print(f"Trying to open camera: {name}.")
+                    continue
+
+                # testing an actual read
+                ret, frame = cap.read()
+                if not ret or frame is None:
+                    cap.release()
+                    continue
+                num_black_pixels = np.count_nonzero(frame == 0)
+                frame_size = frame.size
+                black_pixel_ratio = num_black_pixels / frame_size
+                print(frame)
+                print(f"black_pixels = {num_black_pixels}, frame_size = {frame_size}")
+                print(f"black_pixel_ratio = {black_pixel_ratio}")
+                if black_pixel_ratio > 0.9:
+                    raise RuntimeError("Camera Frame not captured:")
+                print(f"Opened camera: {name}")
+                self.cap = cap
+                return
+            raise RuntimeError("No available camera found or camera busy")
         else:
-            self.cap = cv2.VideoCapture(name)
+            cap = cv2.VideoCapture(name)
+            if not cap.isOpened():
+                raise RuntimeError(f"Unable to open video source:{name}")
+            ret, frame = cap.read()
+            if not ret:
+                cap.release()
+                raise RuntimeError("Camera opened but cannot read ( busy camera )")
+            num_black_pixels = np.count_nonzero(frame == 0)
+            frame_size = frame.size
+            black_pixel_ratio = num_black_pixels / frame_size
+            print(frame)
+            print(f"black_pixels = {num_black_pixels}, frame_size = {frame_size}")
+            print(f"black_pixel_ratio = {black_pixel_ratio}")
+            if black_pixel_ratio > 0.9:
+                raise RuntimeError("Camera Frame not captured:")
+            self.cap = cap
 
     def __reader(self):
         while self.run:
             ret, frame = self.cap.read()
             if not ret:
+                print("Camera read failed. Possibly in use or disconnected")
+                self.run = False
                 break
             if not self.q.empty() and self.bufforless:
                 try:
@@ -225,16 +263,21 @@ def flush(self):
         while not self.q.empty():
             self.q.get()
 
-    def read(self):
-        """Function returning latest frame"""
+    def read(self, timeout = 2):
         if self.stream:
-            return self.q.get()
+            try:
+                return self.q.get(timeout = timeout)
+            except queue.Empty:
+                return (False, None)
+        if len(self.frames) < 1:
+            return (False, None)
         frame = self.frames.pop(0)
         self.frames.pop(0)
         return ((len(self.frames) >= 1), frame)
 
     def close(self):
-        """Function closing stream"""
         self.run = False
-        self.t.join()
-        self.cap.release()
+        if self.stream:
+            self.t.join()
+            if self.cap.isOpened():
+                self.cap.release()