Let's start by importing the OpenCV libary
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# Press CTRL + ENTER to run this line
# You should see an * between the [ ] on the left
# OpenCV takes a couple seconds to import the first time
import cv2
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import cv2
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# Now let's import numpy
# We use as np, so that everything we call on numpy, we can type np instead
# It's short and looks neater
import numpy as np
Let's now load our first image
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# We don't need to do this again, but it's a good habit
import cv2
# Load an image using 'imread' specifying the path to image
input = cv2.imread('./images/input.jpg')
# Our file 'input.jpg' is now loaded and stored in python
# as a varaible we named 'image'
# To display our image variable, we use 'imshow'
# The first parameter will be title shown on image window
# The second parameter is the image varialbe
cv2.imshow('Hello World', input)
# 'waitKey' allows us to input information when a image window is open
# By leaving it blank it just waits for anykey to be pressed before
# continuing. By placing numbers (except 0), we can specify a delay for
# how long you keep the window open (time is in milliseconds here)
cv2.waitKey()
# This closes all open windows
# Failure to place this will cause your program to hang
cv2.destroyAllWindows()
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# Same as above without the extraneous comments
import cv2
input = cv2.imread('./images/input.jpg')
cv2.imshow('Hello World', input)
cv2.waitKey(0)
cv2.destroyAllWindows()
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import cv2
image = cv2.imread('./images/20170407-IMG_5559.dng')
# OpenCV's 'split' function splites the image into each color index
B, G, R = cv2.split(image)
print B.shape
cv2.imshow("Red", R)
cv2.imshow("Green", G)
cv2.imshow("Blue", B)
cv2.waitKey(0)
cv2.destroyAllWindows()
# Let's re-make the original image,
merged = cv2.merge([B, G, R])
cv2.imshow("Merged", merged)
# Let's amplify the blue color
merged = cv2.merge([B+100, G, R])
cv2.imshow("Merged with Blue Amplified", merged)
cv2.waitKey(0)
cv2.destroyAllWindows()
cv2.waitKey(0)
cv2.destroyAllWindows()
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# Import numpy
import numpy as np
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print input.shape
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# Let's print each dimension of the image
print 'Height of Image:', int(input.shape[0]), 'pixels'
print 'Width of Image: ', int(input.shape[1]), 'pixels'
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# Simply use 'imwrite' specificing the file name and the image to be saved
cv2.imwrite('output.jpg', input)
cv2.imwrite('output.png', input)
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