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Python converts images to webp

We can use python to convert image files to webp format to improve website access speed

Table of contents

TL;DR / [Geek Summary]:

  • Site Acceleration: Batch convert bloated JPGs/PNGs to WebP using Pillow to shave milliseconds off page load times.
  • Script Logic: Automates directory traversal with os.walk and tunes output with fine-grained quality controls (quality=80).
  • Geek Edge: Reclaim privacy and speed by ditching online converters for a self-hosted, local media preprocessing pipeline.

# Python batch converts images to webp

Python 3.8.10 is required, I don’t want to use online conversion awa

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import os
import sys
from PIL import Image

def convert_to_webp(input_file, output_file, quality=80):
    try:
        with Image.open(input_file) as im: 
            im.save(output_file, "webp", quality=quality)
            print(f"Converted: {input_file} => {output_file}")
    except Exception as e:
        print(f"Error converting file: {input_file}")
        print(str(e))

def process_folder(folder_path):
    for root, dirs, files in os.walk(folder_path):
        for filename in files:
            if any(filename.lower().endswith(ext) for ext in ['.jpg', '.jpeg', '.png']):
                input_file = os.path.join(root, filename)
                output_file = os.path.splitext(input_file)[0] + ".webp"
                convert_to_webp(input_file, output_file)

if __name__ == "__main__":
    folder_path = os.path.dirname(sys.argv[0])
    process_folder(folder_path)

# Comment version

This code is used to batch convert JPG, JPEG and PNG images in a folder to WEBP format.

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import os # Process files and directories
import sys # Get command line parameters
from PIL import Image # Process images

def convert_to_webp(input_file, output_file, quality=80):
    # Function used to convert an image file
    # input_file: input image file path
    # output_file: output webp file path
    # quality: webp file quality, value range 1-100, default value 80
    try:
        # Open input image file
        with Image.open(input_file) as im:
            # Save in webp format
            im.save(output_file, "webp", quality=quality)
            print(f"Converted: {input_file} => {output_file}")
    except Exception as e:
        # Catch exceptions
        print(f"Error converting file: {input_file}")
        print(str(e))

def process_folder(folder_path):
    # Function used to process the entire folder
    # folder_path: folder path
    for root, dirs, files in os.walk(folder_path):
        for filename in files:
            # Check if the file suffix is ​​jpg/jpeg/png
            if any(filename.lower().endswith(ext) for ext in ['.jpg', '.jpeg', '.png']):
                input_file = os.path.join(root, filename)
                output_file = os.path.splitext(input_file)[0] + ".webp"
                # Call the conversion function
                convert_to_webp(input_file, output_file)

if __name__ == "__main__":
    # Get the current script path
    folder_path = os.path.dirname(sys.argv[0])
    process_folder(folder_path)

# Libraries to be installed

Here are the steps to install the Pillow library:

  1. Make sure you have Python installed.

  2. Open the command prompt (Windows) or terminal (Mac/Linux).

  3. Enter the following command to install Pillow:

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pip install Pillow
  1. After the installation is successful, you can import the Pillow library for image processing:
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from PIL import Image
  1. If you encounter permission issues, you can use sudo or add administrator privileges to install:
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sudo pip install Pillow

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pip install Pillow --user

  1. In Windows, you sometimes need to upgrade pip using the pip install -U Pillow command to install Pillow.

  2. Pillow has some dependencies, so you may also need to install these during installation.

Example installation command:

  • Linux system/Mac: pip install Pillow

  • Windows: pip install Pillow or pip install Pillow --user

The main step is to use pip to install the Pillow library, and then you can import the PIL package in Python code and use Pillow.

# Postscript

Perfectly achieve the requirements of converting webp