【Python OPENCV】 analog clock values opencv
"""
Example to show how to get the values for the hour markings to build the clock
"""
# Import required packages:
import math
radius = 300
center = (320, 320)
for x in (0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330):
x_coordinate = center[0] + radius * math.cos(x * 3.14 / 180)
y_coordinate = center[1] + radius * math.sin(x * 3.14 / 180)
print("x: {} y: {}".format(round(x_coordinate), round(y_coordinate)))
print("..............")
for x in (0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330):
x_coordinate = center[0] + (radius - 20) * math.cos(x * 3.14 / 180)
y_coordinate = center[1] + (radius - 20) * math.sin(x * 3.14 / 180)
print("x: {} y: {}".format(round(x_coordinate), round(y_coordinate)))
【Python OPENCV】 Video Buffer and Threading
import threading, time
import cv2
import queue
input_buffer = queue.Queue()
def processing():
while True:
print("get")
frame=input_buffer.get()
cv2.imshow("Video",frame)
time.sleep(0.025)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
return
cap = cv2.VideoCapture('cats.mp4')
t = threading.Thread(target=processing)
t.start()
while True:
ret, frame = cap.read()
input_buffer.put(frame)
time.sleep(0.025)
print("put")
【Python OPENCV】 argparse load image
"""
Example to load an image using argparse
"""
# Import the required packages
import argparse
import cv2
# We first create the ArgumentParser object# The created object 'parser' will have the necessary information
# to parse the command-line arguments into data types.
parser = argparse.ArgumentParser()
# We add 'path_image' argument using add_argument() including a help. The type of this argument is string (by default)
parser.add_argument("path_image", help="path to input image to be displayed")
# The information about program arguments is stored in 'parser'
# Then, it is used when the parser calls parse_args().
# ArgumentParser parses arguments through the parse_args() method:
args = parser.parse_args()
print(args.path_image)
# We can now load the input image from disk:
image = cv2.imread(args.path_image)
# Parse the argument and store it in a dictionary:
args = vars(parser.parse_args())
# Now, we can also load the input image from disk using args:
image2 = cv2.imread(args["path_image"])
# Show the loaded image:
cv2.imshow("loaded image", image)
cv2.imshow("loaded image2", image2)
# Wait until a key is pressed:
cv2.waitKey(0)
# Destroy all windows:
cv2.destroyAllWindows()
【Python OPENCV】 drawing images
import cv2
import numpy as np
import os
if not os.path.exists('drawing_images'):
os.makedirs('drawing_images')
# Create a black image
image = np.zeros((512,512,3), np.uint8)
# Can we make this in black and white?
image_bw = np.zeros((512,512), np.uint8)
cv2.imshow("Black Rectangle (Color)", image)
cv2.imshow("Black Rectangle (B&W)", image_bw)
cv2.waitKey(0)
cv2.destroyAllWindows()
cv2.imwrite('./drawing_images/black_rectangle.jpg', image)
cv2.imwrite('./drawing_images/black_rectangle_b_w.jpg', image_bw)
image = np.zeros((512,512,3), np.uint8)
cv2.line(image, (0,0), (511,511), (255,127,0), 5)
cv2.imshow("Blue Line", image)
cv2.waitKey(0)
cv2.destroyAllWindows()
cv2.imwrite('./drawing_images/blue_line.jpg', image)
# Draw a Rectangle in
image = np.zeros((512,512,3), np.uint8)
cv2.rectangle(image, (100,100), (300,250), (127,50,127), -1)
cv2.imshow("Rectangle", image)
cv2.waitKey(0)
cv2.destroyAllWindows()
cv2.imwrite('./drawing_images/rectangle.jpg', image)
image = np.zeros((512,512,3), np.uint8)
cv2.circle(image, (350, 350), 100, (15,75,50), -1)
cv2.imshow("Circle", image)
cv2.waitKey(0)
cv2.destroyAllWindows()
cv2.imwrite('./drawing_images/circle.jpg', image)
image = np.zeros((512,512,3), np.uint8)
# Let's define four points
pts = np.array( [[10,50], [400,50], [90,200], [50,500]], np.int32)
# Let's now reshape our points in form required by polylines
pts = pts.reshape((-1,1,2))
cv2.polylines(image, [pts], True, (0,0,255), 3)
cv2.imshow("Polygon", image)
cv2.waitKey(0)
cv2.destroyAllWindows()
cv2.imwrite('./drawing_images/polygon.jpg', image)
image = np.zeros((512,512,3), np.uint8)
cv2.putText(image, 'Hello World!', (75,290), cv2.FONT_HERSHEY_COMPLEX, 2, (100,170,0), 3)
cv2.imshow("Hello World!", image)
cv2.waitKey(0)
cv2.destroyAllWindows()
cv2.imwrite('./drawing_images/hello_world.jpg', image)【Python OPENCV】 histograms
import cv2
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