5 Best Ways to Convert an Image to ASCII Art in Python

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💡 Problem Formulation: Converting images to ASCII art is a creative process of mapping the pixels of an image to characters that approximate the brightness of each pixel. This technique can produce a text-based visual representation that retains some details of the original image. This article describes how to take an input image—such as a JPEG or PNG—and output a text file or console printout that visually resembles the original image using ASCII characters.

Method 1: Using Python’s PIL and Numpy Libraries

This method involves utilizing Python’s Pillow (PIL) library to read the image and the Numpy library to process the pixel data. Each pixel’s brightness is mapped to a corresponding ASCII character, resulting in the ASCII art representation.

Here’s an example:

from PIL import Image
import numpy as np

def convert_to_ascii(image_path, output_file='ascii_image.txt'):
    grayscale_chars = "@%#*+=-:. "
    img = Image.open(image_path).convert('L')
    width, height = img.size
    img = img.resize((width//10, height//10))
    pixel_array = np.array(img)

    with open(output_file, 'w') as f:
        for row in pixel_array:
            line = ''.join(grayscale_chars[pixel//25] for pixel in row)
            f.write(line + '\n')

convert_to_ascii('path_to_image.jpg')

The output is an ASCII art representation of the image contained within 'ascii_image.txt'.

This code snippet opens an image and resizes it to a manageable width and height. The brightness of each pixel is used to select an appropriate ASCII character from the grayscale_chars string. The resulting characters are written to a text file, creating the ASCII art.

Method 2: Using the PyWhatKit Library

PyWhatKit is a simple library that provides utilities to work with WhatsApp among other features including image to ASCII conversion. The library provides a straightforward function that does the conversion without requiring explicit manipulation of the image.

Here’s an example:

import pywhatkit as pwk

def convert_to_ascii_with_pywhatkit(image_path, output_file='ascii_image.txt'):
    pwk.image_to_ascii_art(image_path, output_file)

convert_to_ascii_with_pywhatkit('path_to_image.jpg')

The output is a .txt file named 'ascii_image.txt' containing the ASCII art version of the provided image.

This code uses the function image_to_ascii_art() from the PyWhatKit library to handle the conversion of the input image to ASCII art. The ASCII art is then saved to the designated text file.

Method 3: Using ASCII Art Libraries

Specialized ASCII art libraries, like `ascii_magic`, can convert images to ASCII art with a variety of options for customization. This method focuses on using such a library to accomplish the task.

Here’s an example:

import ascii_magic

def convert_to_ascii_with_magic(image_path):
    output = ascii_magic.from_image_file(image_path)
    ascii_magic.to_file('ascii_image.txt', output)

convert_to_ascii_with_magic('path_to_image.jpg')

The output is a text file named 'ascii_image.txt' containing the generated ASCII art.

By using the `ascii_magic` library, this snippet reads an image file and converts it to ASCII art which is then saved to a .txt file. Various output customization options are available in the library to tweak the art generation.

Method 4: Using OpenCV and ASCII Mappings

Using OpenCV, one can read and manipulate image data at a low level, and by applying a simple ASCII mapping, it is possible to convert images to ASCII art with precise control over the process.

Here’s an example:

import cv2

def convert_to_ascii_with_opencv(image_path, output_file='ascii_image.txt'):
    grayscale_chars = "@%#*+=-:. "
    img = cv2.imread(image_path, 0)
    height, width = img.shape
    img = cv2.resize(img, (width//10, height//10))

    with open(output_file, 'w') as f:
        for y in range(0, img.shape[0]):
            for x in range(0, img.shape[1]):
                f.write(grayscale_chars[img[y][x] // 25])
            f.write('\n')

convert_to_ascii_with_opencv('path_to_image.jpg')

The output is a file named 'ascii_image.txt', which displays the ASCII art of the image.

This code uses OpenCV to read the image in grayscale mode, and resize it for easier processing. The pixels are then mapped to ASCII characters which are written to an output file, creating the ASCII art representation.

Bonus One-Liner Method 5: Using Python’s Art Library

For a quick and straightforward approach, the Python ‘art’ library offers a convenient one-liner function to create ASCII art from an image.

Here’s an example:

from art import *

def convert_to_ascii_one_liner(image_path):
    print(art("random"))
    print(a2a_from_image(image_path))

convert_to_ascii_one_liner('path_to_image.jpg')

The output is ASCII art representing the given image, displayed in the console.

This code simply calls the a2a_from_image() function from the ‘art’ library, which takes the path to an image and prints out its ASCII art representation to the console.

Summary/Discussion

  • Method 1: Using PIL and Numpy. Strengths: Offers fine control over the conversion process and allows pre-processing of images using powerful image manipulation libraries. Weaknesses: Requires multiple libraries and more lines of code.
  • Method 2: Using PyWhatKit. Strengths: Extremely simple and requires minimal code. Weaknesses: Less customization and depends on an external library that might be less specialized in ASCII art.
  • Method 3: Using ASCII Art Libraries. Strengths: Designed for ASCII art creation, offering customization and convenience. Weaknesses: Limited flexibility compared to more general image processing libraries.
  • Method 4: Using OpenCV and ASCII Mappings. Strengths: Offers the most control and customization over the resulting ASCII art. Weaknesses: It requires familiarity with OpenCV and more complex code.
  • Bonus Method 5: Using Python’s Art Library. Strengths: The simplest and fastest way to get ASCII art from an image. Weaknesses: Offers little to no customization and is limited to console output.