added picamera streaming

controller/utils/camera.py

@@ -1,6 +1,10 @@
 import cv2
 import threading
 import uuid
+# import the necessary packages
+from picamera.array import PiRGBArray # Generates a 3D RGB array
+from picamera import PiCamera # Provides a Python interface for the RPi Camera Module
+import time # Provides time-related functions
 
 class RecordingThread(threading.Thread):
     def __init__(self, name, camera):
@@ -35,8 +39,12 @@ def __del__(self):
 
 class VideoCamera(object):
     def __init__(self, camera_id=0):
-        # 打开摄像头， 0代表笔记本内置摄像头
-        self.cap = cv2.VideoCapture(camera_id, cv2.CAP_DSHOW)
+        self.is_picamera = False
+        if 'picamera' in camera_id:
+            self.cap, self.raw_capture = self.init_picamera()
+            self.is_picamera = True
+        else:
+            self.cap = cv2.VideoCapture(camera_id, cv2.CAP_DSHOW)
 
         # 初始化视频录制环境
         self.is_record = False
@@ -45,21 +53,49 @@ def __init__(self, camera_id=0):
         # 视频录制线程
         self.recordingThread = None
 
+    def init_picamera (self):
+        camera = PiCamera()
+        camera.resolution = (640, 480)
+        camera.framerate = 20
+        raw_capture = PiRGBArray(camera, size=(640, 480))
+        time.sleep(0.1)
+        return camera, raw_capture
+
+
     # 退出程序释放摄像头
     def __del__(self):
         self.cap.release()
 
     def get_frame(self):
-        ret, frame = self.cap.read()
+        if self.is_picamera:
+            for frame in self.cap.capture_continuous(self.raw_capture, format="bgr", use_video_port=True):
+
+                # Grab the raw NumPy array representing the image
+                image = frame.array
+
+                if image:
+                    ret1, jpeg = cv2.imencode('.jpg', frame)
+
+                    if ret1:
+                        return jpeg.tobytes()
+
+
+                    # Clear the stream in preparation for the next frame
+                    self.raw_capture.truncate(0)
+
+                else:
+                    return None
+        else:
+            ret, frame = self.cap.read()
 
-        if ret:
-            ret1, jpeg = cv2.imencode('.jpg', frame)
+            if ret:
+                ret1, jpeg = cv2.imencode('.jpg', frame)
 
-            if ret1:
-                return jpeg.tobytes()
+                if ret1:
+                    return jpeg.tobytes()
 
-        else:
-            return None
+            else:
+                return None
 
     def start_record(self):
         self.is_record = True