Create 1 x 1 Pixel Image (Gray & RGB) using Python

1. Gray Image (for the pixel intensity from 0 to 255)

import numpy as np

import matplotlib.pyplot as plt

w = 1h = 1
imgArray = np.zeros([h, w, 3],dtype = np.uint8)

for i in range(1,256):
    plt.subplot(16,16,i)
    plt.axis('off')
    imgArray[:, :] = [i - 1]
    print(str(i) + ' >>> ' + str(imgArray))
    plt.imshow(imgArray)

plt.show()

Output

1 >>> [[[0 0 0]]]
2 >>> [[[1 1 1]]]
3 >>> [[[2 2 2]]]
4 >>> [[[3 3 3]]]
5 >>> [[[4 4 4]]]
6 >>> [[[5 5 5]]]
7 >>> [[[6 6 6]]]
8 >>> [[[7 7 7]]]
9 >>> [[[8 8 8]]]
10 >>> [[[9 9 9]]]
11 >>> [[[10 10 10]]]
12 >>> [[[11 11 11]]]

...

256 >>> [[[255 255 255]]]

2. RGB Image (for the pixel intensity from 0 to 255)


import numpy as np
import matplotlib.pyplot as plt

w = 1h = 1
imgArray = np.zeros([h, w, 3],dtype = np.uint8)

for i in range(1,256):
    plt.subplot(16,16,i)
    plt.axis('off')
    imgArray[:, :] = [255, 128, i - 1]
    print(str(i) + ' >>> ' + str(imgArray))
    plt.imshow(imgArray)

plt.show()

Output

1 >>> [[[255 128   0]]]
2 >>> [[[255 128   1]]]
3 >>> [[[255 128   2]]]
4 >>> [[[255 128   3]]]
5 >>> [[[255 128   4]]]
6 >>> [[[255 128   5]]]
7 >>> [[[255 128   6]]]
8 >>> [[[255 128   7]]]
9 >>> [[[255 128   8]]]
10 >>> [[[255 128   9]]]
11 >>> [[[255 128  10]]]
12 >>> [[[255 128  11]]]
...
256 >>> [[[255 128  255]]]