In this article, we will learn how to convert a NumPy Array to an image in Python.

**Table Of Contents**

- How the images are stored in a computer?
- Convert NumPy Array to Image using fromarray() from pillow library
- Convert NumPy Array to Image using imsave() from matplotlib.pyplot
- Convert NumPy Array to Image using imwrite() from imageio module
- Convert NumPy Array to Image using imwrite() from opencv module

Given a NumPy array we need to convert it into an image in Python.

## How the images are stored in a computer?

The usual black and white images are represented using a matrix. Where each cell in the matrix represent a pixel and the pixel color is either black or white. The value in the cell represent the intensity of the color, like 0 is for black and 255 is for white. The color intensity changes with the numbers in cell. So we will create a numpy array with size as (144 x 144) and fill it with random values between 0 and 255. Later we will convert this 2D NumPy Array into an image.

There are multiple ways to convert a NumPy Array to an image in Python. Lets discuss all the methods one by one with proper approach and a working code example

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## Convert NumPy Array to Image using fromarray() from pillow library

The pillow library has an image module. This image module provide a fromarray() method, to convert the array into any image format. We will create a 2D NumPy Aarray and will pass that array to the fromarray() method.

Let’s have a quick look at the functions that we are going to use in this example,

**Syntax of randint()**

random.randint(low, high=None, size=None, dtype=int)

- Parameters:
- low = least value of the random number to be generated.
- high = highest value of the random number to be generated.
- size = This specifies the shape of the numpy array to be created
- dtype = datatype of array, by default it is int.

- Returns:
- Returns a numpy array filled with random numbers

**Syntax of fromarray()**

PIL.Image.fromarray(Array)

- Parameters:
- Array = Array which needs to be converted into image.

- Returns:
- Returns a Image object.

**Syntax of save()**

Image.save(fp)

- Parameters:
- fp = Name or path of the image file to be saved.

- Returns:
- None

**The Approach to convert NumPy Array to an Image:**

- Import numpy library and create 2D NumPy array using randint() method.
- Pass this array to the fromarray() method. This will return an image object.
- Save the image to the filesystem using the save() method.

**Source Code**

from PIL import Image import numpy as np # Creating the 144 X 144 NumPy Array with random values arr = np.random.randint(255, size=(144, 144), dtype=np.uint8) # Converting the numpy array into image img = Image.fromarray(arr) # Saving the image img.save("Image_from_array.png") print(" The Image is saved successfully")

**Output:**

The Image is saved successfully

It will create an image file with name “Image_from_array.png” in the same folder. Image file will be like this,

If you get an error like this,

ModuleNotFoundError: No module named 'PIL'

Then use the following command to install the pillow module,

pip3 install Pillow

## Convert NumPy Array to Image using imsave() from matplotlib.pyplot

The matplotlib.pyplot module provide an imsave() method to convert the array into any image format. Create a numpy array and pass that array to the imsave() method.

Let’s have a quick look at the functions that we are going to use in this example,

**Syntax of imsave()**

matplotlib.pyplot.imsave(fp, Array)

- Parameters:
- Array = Array which needs to be converted into image.
- fp = Name or path to save the image.

- Returns:
- None

**The Approach to convert NumPy Array to an Image:**

- Import numpy library and create 2D NumPy array using randint() method.
- Pass this array to the imsave() method.
- The image will be saved to the path mentioned in the method arguments.

**Source Code:**

import matplotlib.pyplot as mp import numpy as np # Creating the 144 X 144 NumPy Array with random values arr = np.random.randint(255, size=(144, 144),dtype=np.uint8) # Converting the NumPy Array into an image mp.imsave("Image_from_array.png", arr) print(" The Image is saved successfully ")

**Output:**

The Image is saved successfully

It will create an image file with name “Image_from_array.png” in the same folder. Image file will be like this,

It might be possible that you can get an error, if matplotlib module is not installed. Like,

ModuleNotFoundError: No module named 'matplotlib'

Then use the following command to install the matplotlib module,

pip3 install matplotlib

## Convert NumPy Array to Image using imwrite() from imageio module

The imageio module provide imwrite() method to convert the array into any image format. We will create a numpy array and pass the array to imwrite() method.

**Syntax of imwrite()**

imageio.imwrite(fp, Array)

- Parameters:
- Array = Array which needs to be converted into image.
- fp = Name or path to save the image.

- Returns:
- None

**The Approach to convert NumPy Array to an Image:**

- Import numpy library and create numpy array using randint() method.
- Pass this array to the imwrite() method.
- The image will be saved to the path mentioned in the method.

**Source Code:**

import imageio import numpy as np # Creating the 144 X 144 NumPy Array with random values arr = np.random.randint(255, size=(144, 144), dtype=np.uint8) # Converting the numpy array into image imageio.imwrite('Image_from_array.png', arr) print(" The Image is saved successfully ")

**Output:**

The Image is saved successfully

It will create an image file with name “Image_from_array.png” in the same folder. Image file will be like this,

It might be possible that you can get an error, if imageio module is not installed. Like,

ModuleNotFoundError: No module named 'imageio'

Then use the following command to install the imageio module,

pip3 install imageio

## Convert NumPy Array to Image using imwrite() from opencv module

The opencv module provide imwrite() method to convert the array into any image format. We will create a numpy array and pass the array to imwrite() method

**Syntax of imwrite()**

cv2.imwrite(fp, Array)

- Parameters:
- Array = Array which needs to be converted into image.
- fp = Name or path to save the image.

- Returns:
- None

**The Approach to convert NumPy Array to an Image:**

- Import numpy library and create numpy array using randint() method.
- Pass this array to the imwrite() method.
- The image will be saved to the path mentioned in the method.

**Source Code**

import cv2 import numpy as np # Creating the 144 X 144 NumPy Array with random values arr = np.random.randint(255, size=(144, 144),dtype=np.uint8) # Converting the numpy array into image cv2.imwrite('Image_from_array.png', arr) print(" The Image is saved successfully ")

**Output:**

The Image is saved successfully

It might be possible that you can get an error, if opencv-python module is not installed. Like,

ModuleNotFoundError: No module named 'cv2'

Then use the following command to install the opencv-python module,

pip3 install opencv-python

**Summary**

Great! you made it, We have discussed All possible methods to convert a NumPy Array to an image in Python. Happy learning.

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Thanks for reading.