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How can I convert an RGB image into grayscale in Python?
...png')
Using matplotlib and the formula
Y' = 0.2989 R + 0.5870 G + 0.1140 B
you could do:
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
def rgb2gray(rgb):
return np.dot(rgb[...,:3], [0.2989, 0.5870, 0.1140])
img = mpimg.imread('image.png')
gra...
How to read the content of a file to a string in C?
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145
I tend to just load the entire buffer as a raw memory chunk into memory and do the parsing on m...
How to correctly use the extern keyword in C
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Iharob Al Asimi
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answered Jan 30 '09 at 17:49
bluebrotherbluebrot...
Spring Boot - inject map from application.yml
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answered Jul 23 '14 at 21:27
Andy WilkinsonAndy Wilkinson
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Java and SQLite [closed]
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edited Jun 19 '15 at 17:54
Display Name
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String concatenation in Ruby
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edited Jan 1 '16 at 20:14
scarver2
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answered De...
MySQL, better to insert NULL or empty string?
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4
but which one you think is faster? 0 or NULL or ""
– Atul Dravid
Oct 16 '10 at 23:48
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Best practices for storing postal addresses in a database (RDBMS)?
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14 Answers
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Do AJAX requests retain PHP Session info?
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answered Mar 24 '09 at 11:10
thomasrutterthomasrutter
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Painless way to install a new version of R?
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edited May 8 '19 at 2:46
Gregor Thomas
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