Image to ASCII Art

This project converts images into ASCII art using Python. Below is the chunk-by-chunk explanation of the code with each chunk in its own code block and a short description.

1. Importing required libraries

This chunk imports the PIL library for image manipulation and os.path to check file paths.

from PIL import Image
import os.path 

2. Mapping grayscale values to ASCII characters

Defines a dictionary that maps ranges of grayscale values to ASCII characters for visualization.

# setting ASCII values based on the gray scale
VALUES = {
    30:" ",
    60 :"*",
    100: "%",
    150 :"o",
    255 :"@"
}

3. Defining output image size

Sets the width and height for the resized image to ensure proper ASCII art proportion.

# setting the picture new size width and height
W, H = 60, 30

4. Calculating grayscale of a pixel

A function to convert an RGB pixel to a single grayscale value by averaging the channels.

# Calculating the gray scale (summing the rgb values and dividing by 3)
def calculate_gray_scale(pixel_rgb_values):
    pix = 0 
    for z in range(3):
            pix = pix + pixel_rgb_values[z]
    return pix / 3

5. Mapping grayscale to ASCII character

This function takes a grayscale value and returns the corresponding ASCII character from VALUES.

# Output valid ASCII character (comparing to the VALUES dictionary)
def get_valid_char(gray_scale):
    for z in VALUES:
        if (gray_scale <= z):
            return VALUES[z]

6. Main function: input and validation

Prompts the user to input a local image path and validates the file type.

def main():
    # Getting the picture path and checking validity
    path = input("insert your full image path here (should be local):")
    if not os.path.isfile(path) or not path.lower().endswith(('.png', '.jpg', '.jpeg')):
        return main()

7. Opening and resizing the image

Opens the image with PIL and resizes it to the predefined width and height.

    # Opening image and resizing it for better quality
    myImage = Image.open(path)
    myImage = myImage.resize((W,H))

8. Extracting pixel data and building output

Loops through each pixel, converts it to grayscale, maps to ASCII, and builds the final output string.

    # Declaring the output string
    output = "\n"

    # Extracting the pixel values
    pixel_values = list(myImage.getdata())

    # Generating the output ASCII string
    for y in range(H):
        for x in range(W):
            pix = calculate_gray_scale(pixel_values[x + W * y])
            output = output + get_valid_char(pix)
        output = output + "\n"

9. Printing and restarting

Prints the generated ASCII art and restarts the script to allow processing another image.

    # Printing out
    print(output)
    
    # Restarting the script
    main()

# Starting the script
main()

This chunk-by-chunk explanation shows how the program converts any local image into ASCII art while keeping it readable and reusable.