Converting an image to black and white
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This code is a project that I am working on to eventually analyze some images but right now I am purely trying to read an image and convert it to black and white. The input should be either white or something else which would end up as black so it is easy to check for this.
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
import numpy as np
img = mpimg.imread('./Training/Image1.png')
imgplot = plt.imshow(img)
width = img.shape[1]
height = img.shape[0]
def generateArray():
arr =
for y in range(img.shape[0]):
arr.append()
for x in range(img.shape[1]):
if img[y][x][0] != 1:
arr[y].append(1)
else:
arr[y].append(0)
return arr
arr = generateArray()
plt.show()
To be clear, I desire to create an array arr that contains either a 0 if the corresponding pixel in the inputted image is white or 1 if it is anything other than white.
I am somewhat of a beginner with Python but I am confused as to why this code takes so long to run (>19 seconds on my older Mac). Is there something that I am missing that would speed it up significantly?
python performance
edited 14 mins ago
Jamal♦
30.2k11115226
asked 47 mins ago
dalearn
1113
add a comment |
up vote
0
down vote
favorite
This code is a project that I am working on to eventually analyze some images but right now I am purely trying to read an image and convert it to black and white. The input should be either white or something else which would end up as black so it is easy to check for this.
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
import numpy as np
img = mpimg.imread('./Training/Image1.png')
imgplot = plt.imshow(img)
width = img.shape[1]
height = img.shape[0]
def generateArray():
arr =
for y in range(img.shape[0]):
arr.append()
for x in range(img.shape[1]):
if img[y][x][0] != 1:
arr[y].append(1)
else:
arr[y].append(0)
return arr
arr = generateArray()
plt.show()
To be clear, I desire to create an array arr that contains either a 0 if the corresponding pixel in the inputted image is white or 1 if it is anything other than white.
I am somewhat of a beginner with Python but I am confused as to why this code takes so long to run (>19 seconds on my older Mac). Is there something that I am missing that would speed it up significantly?
python performance
edited 14 mins ago
Jamal♦
30.2k11115226
asked 47 mins ago
dalearn
1113
add a comment |
up vote
0
down vote
favorite
up vote
0
down vote
favorite
This code is a project that I am working on to eventually analyze some images but right now I am purely trying to read an image and convert it to black and white. The input should be either white or something else which would end up as black so it is easy to check for this.
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
import numpy as np
img = mpimg.imread('./Training/Image1.png')
imgplot = plt.imshow(img)
width = img.shape[1]
height = img.shape[0]
def generateArray():
arr =
for y in range(img.shape[0]):
arr.append()
for x in range(img.shape[1]):
if img[y][x][0] != 1:
arr[y].append(1)
else:
arr[y].append(0)
return arr
arr = generateArray()
plt.show()
To be clear, I desire to create an array arr that contains either a 0 if the corresponding pixel in the inputted image is white or 1 if it is anything other than white.
I am somewhat of a beginner with Python but I am confused as to why this code takes so long to run (>19 seconds on my older Mac). Is there something that I am missing that would speed it up significantly?
python performance
edited 14 mins ago
Jamal♦
30.2k11115226
asked 47 mins ago
dalearn
1113
This code is a project that I am working on to eventually analyze some images but right now I am purely trying to read an image and convert it to black and white. The input should be either white or something else which would end up as black so it is easy to check for this.
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
import numpy as np
img = mpimg.imread('./Training/Image1.png')
imgplot = plt.imshow(img)
width = img.shape[1]
height = img.shape[0]
def generateArray():
arr =
for y in range(img.shape[0]):
arr.append()
for x in range(img.shape[1]):
if img[y][x][0] != 1:
arr[y].append(1)
else:
arr[y].append(0)
return arr
arr = generateArray()
plt.show()
To be clear, I desire to create an array arr that contains either a 0 if the corresponding pixel in the inputted image is white or 1 if it is anything other than white.
I am somewhat of a beginner with Python but I am confused as to why this code takes so long to run (>19 seconds on my older Mac). Is there something that I am missing that would speed it up significantly?
python performance
python performance
edited 14 mins ago
Jamal♦
30.2k11115226
asked 47 mins ago
dalearn
1113
edited 14 mins ago
Jamal♦
30.2k11115226
asked 47 mins ago
dalearn
1113
edited 14 mins ago
Jamal♦
30.2k11115226
edited 14 mins ago
Jamal♦
30.2k11115226
edited 14 mins ago
Jamal♦
30.2k11115226
30.2k11115226
asked 47 mins ago
dalearn
1113
asked 47 mins ago
dalearn
1113
asked 47 mins ago
dalearn
1113
1113
add a comment |
add a comment |
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