OpenCV Experiments

Experiment with

• Logging
• Threads
• Error Handling
• Writing text on Frame with grey background

	#Logging
	#Frame processing
	#Video Stats Frames per second
	#Custom text with background
	import cv2
	import numpy as np
	import logging
	import time
	#Initialize Logging module
	#now we will Create and configure logger
	logging.basicConfig(filename=r"C:\demo\videolog.log",
	format='%(asctime)s %(message)s',
	filemode='a')
	#Let us Create an object
	logger=logging.getLogger()
	#Now we are going to Set the threshold of logger to DEBUG
	logger.setLevel(logging.DEBUG)
	# Create a VideoCapture object and read from input file
	cap = cv2.VideoCapture(r'C:\demo\video2.mp4')
	# Check if camera opened successfully
	if (cap.isOpened()== False):
	print("Error opening video file")
	icount = 0
	#### overlay space
	x,y,w,h = 10,30,700,30
	#Check frames per second
	fps = cap.get(cv2.CAP_PROP_FPS)
	# Read until video is completed
	while(cap.isOpened()):
	# Capture frame-by-frame
	ret, frame_source = cap.read()
	if ret == True:
	frame = cv2.resize(frame_source, (800,600))
	# Draw black background rectangle
	cv2.rectangle(frame, (x, x), (x + w, y + h), (0,0,0), -1)
	frmtext = 'Frames Per Second-' + str(fps) + ' - Frame Count - ' + str(icount)
	# Add text
	cv2.putText(frame, frmtext, (x + int(w/10),y + int(h/2)), cv2.FONT_HERSHEY_SIMPLEX, 0.7, (255,255,255), 2)
	logger.info(frmtext)
	# Display the resulting frame
	cv2.imshow('Frame', frame)
	# Press Q on keyboard to exit
	if cv2.waitKey(25) & 0xFF == ord('q'):
	break
	icount = icount+1
	# Break the loop
	else:
	break
	# When everything done, release
	# the video capture object
	cap.release()
	# Closes all the frames
	cv2.destroyAllWindows()
	logging.shutdown()

view raw VideoExample.py hosted with ❤ by GitHub

	#Thread with parameters
	from threading import Thread
	import time
	def read_value(i):
	print("Read value is: " + str(i))
	i = 0
	while i < 10:
	read_thread = Thread(target=read_value,args=(i,))
	read_thread.start()
	i = i + 1

view raw Threadexample.py hosted with ❤ by GitHub

	import cv2
	import datetime
	vcap = cv2.VideoCapture(r'C:\Users\video3.mp4') # 0=camera
	if vcap.isOpened():
	width = vcap.get(cv2.CAP_PROP_FRAME_WIDTH)
	height = vcap.get(cv2.CAP_PROP_FRAME_HEIGHT)
	fps = vcap.get(cv2.CAP_PROP_FPS)
	frames = vcap.get(cv2.CAP_PROP_FRAME_COUNT)
	seconds = int(frames / fps)
	video_time = str(datetime.timedelta(seconds=seconds))
	print("duration in seconds:", seconds)
	print("video time:", video_time)
	print("width:", width)
	print("Height:", height)

view raw videostats.py hosted with ❤ by GitHub

	#Mulththread and call back
	#Thread with parameters
	#https://pythonexamples.org/python-callback-function/
	from threading import Thread
	import time
	def callbackFunc1(results):
	print('results - callback')
	print(results[0])
	print(results[1])
	def read_value(i,callbackFunc1):
	print("Read value is: " + str(i))
	square = i*i
	cube = i*i*i
	results = [square,cube]
	callbackFunc1(results)
	i = 0
	while i < 10:
	read_thread = Thread(target=read_value,args=(i,callbackFunc1,))
	read_thread.start()
	i = i + 1

view raw Mulththreadcallback.py hosted with ❤ by GitHub

Keep Exploring!!!