Printing Images With Python-CodePudding

I want to plot a 37x37 black&white image, so far I have created a matrix and was hoping to get black pixels for 1's and white pixels for 0's. I dont know what went wrong.

import numpy as np
from PIL import Image
cols37 = [1,0,1,1,0,0,1,0,1,1,1,1,0,0,0,1,0,0,0,0,1,0,0,0,1,1,1,1,0,1,0,0,1,1,0,1]
rows = []

for i in range (37):
    rows.append(cols37)

mura = np.array(rows, dtype = np.bool)
temp = Image.fromarray(mura, '1')
temp.save('my1.png')
temp.open('my1.png')

I am currently getting this image:

current output

Instead, I am supposed to get something like this:

desired output

CodePudding user response：

It is caused by two issues

Option mode specified with '1' will get rawmode '1;8', then it will decode wrong raw data from numpy array, remove option '1' will get rawmode '1', also result image with mode '1'.
Same row data in rows, so you won't get right image as requested, or ten vertical black lines in your images.

import numpy as np
from PIL import Image

cols37 = [1,0,1,1,0,0,1,0,1,1,1,1,0,0,0,1,0,0,0,0,1,0,0,0,1,1,1,1,0,1,0,0,1,1,0,1,0]
rows = []

for i in range (37):
    rows.append(cols37)

mura = np.array(rows, dtype = np.bool)
temp = Image.fromarray(mura)        # temp.mode will be `'1'`

import numpy as np
from PIL import Image

cols37 = [1,0,1,1,0,0,1,0,1,1,1,1,0,0,0,1,0,0,0,0,1,0,0,0,1,1,1,1,0,1,0,0,1,1,0,1,0]
row_data = [255 if item else 0 for item in cols37]
rows = [row_data for i in range(37)]

mura = np.array(rows, dtype=np.uint8)
temp = Image.fromarray(mura, mode='L')
temp.convert('1')

Both scripts will get same image

Update: Actually, there's only 36 data in cols37, here I convert your data from 1D to 2D with NOT XOR operation , then get picture like yours.

import numpy as np
from PIL import Image

cols36 = [1,0,1,1,0,0,1,0,1,1,1,1,0,0,0,1,0,0,0,0,1,0,0,0,1,1,1,1,0,1,0,0,1,1,0,1]
row = cols36   cols36[::-1]

rows = []
for y in range(72):
    line = []
    for x in range(72):
        line.append(not(row[x] != row[y]))
    rows.append(line)
    line = []

mura = np.array(rows, dtype = np.bool)
im = Image.fromarray(mura)        # temp.mode will be `'1'`
im.show()