How to convert a 0, 255 binary image to a 0, 1 binary image?

Question

I have an image img in the form

array([[  0,   0,   0, ..., 255, 255, 255],
       [  0,   0,   0, ..., 255, 255,   0],
       [  0,   0,   0, ..., 255,   0,   0],
        ...,
       [  0,   0,   0, ...,   0,   0,   0],
       [  0,   0,   0, ...,   0,   0,   0],
       [  0,   0,   0, ...,   0,   0,   0]], dtype=uint8)

Is there any build in python function that convert images like that to 0,1 binarization?

See * https://stackoverflow.com/questions/1735025/how-to-normalize-a-numpy-array-to-within-a-certain-range * for your answer. — zgebac26, Nov 16 '20 at 13:11

score 1 · Answer 1 · answered Nov 16 '20 at 13:18

Your each row is a list, and from each list you want to check whether the value is 255 or not. If it is 255 convert to 1.

To get the index of each row and column , you can enumerate through the list

for i, v1 in enumerate(img):
    for j, v2 in enumerate(v1):
        if v2 == 255:
            img[i, j] = 1

Result:

[[0 0 0 1 1 1]
 [0 0 0 1 1 0]
 [0 0 0 1 0 0]
 [0 0 0 0 0 0]
 [0 0 0 0 0 0]
 [0 0 0 0 0 0]]

Code:

import numpy as np

img = np.array([[0,   0,   0, 255, 255, 255],
                [0,   0,   0, 255, 255,   0],
                [0,   0,   0, 255,   0,   0],
                [0,   0,   0,   0,   0,   0],
                [0,   0,   0,   0,   0,   0],
                [0,   0,   0,   0,   0,   0]], dtype=np.uint8)

for i, v1 in enumerate(img):
    for j, v2 in enumerate(v1):
        if v2 == 255:
            img[i, j] = 1

print(img)

score 0 · Answer 2 · answered Nov 23 '21 at 10:23

0

Simply divide whole image with 255 as treat as float,

img = img / 255.

answered Nov 23 '21 at 10:23

DomagojM

81
1
3

How to convert a 0, 255 binary image to a 0, 1 binary image?

2 Answers2