PiVideoStream.py

# ****************************************************************************** #
# Author: Ondrej Slama
# -------------------

# Zdrojovy kod vytvoreny v ramci projektu robotickeho vzdusneho hokeje - diplomova prace
#  na VUT FSI ustavu automatizace a informatiky v Brne.

# Source code created as a part of robotic air hockey table project - Diploma thesis
# at BUT FME institute of automation and computer sience.

# ****************************************************************************** #
# import the necessary packages
from picamera.array import PiRGBArray
from picamera import PiCamera
from threading import Thread
from UniTools import FPSCounter, Repeater
import cv2
import time
 
class PiVideoStream:
	def __init__(self, resolution=(320, 240), framerate=60, wb = (1.5,1.5)):
		# initialize the camera and stream
		self.camera = PiCamera()
		self.camera.resolution = resolution
		self.camera.framerate = framerate
		self.camera.awb_mode = "off"
		self.camera.awb_gains = wb
		self.rawCapture = PiRGBArray(self.camera, size=resolution)
		self.stream = self.camera.capture_continuous(self.rawCapture,
			format="bgr", use_video_port=True)
		self.newFrame = False

		self.counter = FPSCounter(movingAverage=60).start()


		# initialize the frame and the variable used to indicate
		# if the thread should be stopped
		self.frame = None
		self.stopped = True

	def start(self):
		# start the thread to read frames from the video stream
		if self.stopped:
			self.stopped = False
			Thread(target=self.update, args=()).start()
			return self
 
	def update(self):
		# keep looping infinitely until the thread is stopped
		print("Warming up...")
		time.sleep(1.0)
		print("Done")

		print("Camera is running.")
		try:
			for f in self.stream:
				# grab the frame from the stream and clear the stream in
				# preparation for the next frame
				self.frame = cv2.flip(f.array, 0 )
				self.rawCapture.truncate(0)
				self.newFrame = True
				self.counter.tick()
	
				# if the thread indicator variable is set, stop the thread
				# and resource camera resources
				if self.stopped:
					self.stream.close()
					self.rawCapture.close()
					self.camera.close()
					print("Camera stopped.")
					return
		except:
			self.frame = None

	def read(self):
		# return the frame most recently read
		self.newFrame = False
		return self.frame
 
	def stop(self):
		# indicate that the thread should be stopped
		self.stopped = True
		self.newFrame = False
		self.frame = None
		self.counter.stop()
		

if __name__ == "__main__":
	pass

	piVideo = PiVideoStream()
	piVideo.start()

	repeater = Repeater(piVideo.counter.print, 0.5).start()