Question: I have an array of binary numbers in Python:

```
data = [0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1...]

```

I would like to take this data out and save it as a bitmap, with a '0' corresponding to white and a '1' corresponding to black. I know that there are 2500 numbers in the array, corresponding to a 50x50 bitmap. I've downloaded and installed PIL, but I'm not sure how to use it for this purpose. How can I convert this array into the corresponding image?

Answer: 
You can use `Image.new` with [`1`](https://pillow.readthedocs.io/en/4.1.x/handbook/concepts.html#concept-modes) mode and put each integer as pixel in your initial image:

```
>>> from PIL import Image
>>> import random

>>> data = [random.choice((0, 1)) for _ in range(2500)]
>>> data[:] = [data[i:i + 50] for i in range(0, 2500, 50)]
>>> print data
[[0, 1, 0, 0, 1, ...], [0, 1, 1, 0, 1, ...], [1, 1, 0, 1, ...], ...]

>>> img = Image.new('1', (50, 50))
>>> pixels = img.load()

>>> for i in range(img.size[0]):
...    for j in range(img.size[1]):
...        pixels[i, j] = data[i][j]

>>> img.show()
>>> img.save('/tmp/image.bmp')

```

[![enter image description here](https://i.stack.imgur.com/Kwycg.png)](https://i.stack.imgur.com/Kwycg.png)
**Not for binary array**

In case you have **binary data** in this format - `b'\x89PNG\r\n\x1a\n\x00\x00\x00\rIHDR\x00...`, then you may use this method to write it as an image file:

```
with open("image_name.png", "wb") as img:
    img.write(binary_data)

```