Django Image Optimizer

   

Django Image Optimizer converts images to WebP format while allowing you to specify the quality of the image. Optimized images that are larger than their originals are automatically deleted.

Installation

pip install django-img-optimizer

Configuration

Add django_img_optimizer to INSTALLED_APPS in your projects settings.py file:

    INSTALLED_APPS = [
        ...
        'django_img_optimizer',
        ...
    ]

Set OPTIMIZE_IMAGE_ROOT to the top-level folder containing the images that you would like to optimize. django_img_optimizer will search through all subfolders for the specified image types.

Example:

If you have a folder inside static called images:

OPTIMIZE_IMAGE_ROOT = PROJECT_DIR / "static" / "images"

Note: The path above uses a Path object (from pathlib import Path).

---

Optional Settings

Image Quality

OPTIMIZE_IMAGE_QUALITY specifies the optimization image quality on a scale from 0 (lowest) to 100 (best). The lower the quality, the smaller the size of the file.

Default is 100.

Example:

OPTIMIZE_IMAGE_QUALITY = 100

---

Image Types

OPTIMIZE_IMAGE_TYPES specifies a list of image types that you want to optimize.

Default is ['jpg', 'jpeg', 'png'].

Example:

OPTIMIZE_IMAGE_TYPES = ['jpg', 'jpeg', 'png']

---

Exclude Folders

OPTIMIZE_IMAGE_EXCLUDED_FOLDERS is used to exclude specific folders from the optimization process.

Default is None.

Example:

OPTIMIZE_IMAGE_EXCLUDED_FOLDERS = ['backup-larger-versions']

Usage

Command line

Optimize all images:

python manage.py optimize_images

Delete all optimized images:

python manage.py optimize_images --delete

Django templates

Load the optimized images in Django templates:

{% load image_optimizer %}

{% optimized_image loading="lazy" decoding="async" src="images/logo.jpg" alt="Logo" class="img-fluid" %}

This will render:

<picture>
    <source srcset="/static/images/logo.webp" type="image/webp">
    <img loading="lazy" decoding="async" src="/static/images/logo.jpg" alt="Logo" class="img-fluid">
</picture>

You can use auto to generated the value of the alt and title attribute automatically using its filename.

Example:

{% optimized_image loading="lazy" decoding="async" src="images/logo-auto-attributes.jpg" alt="auto" title="auto" %}

This will render alt="Logo Auto Attributes" and title="Logo Auto Attributes".

You can use variables with the optimize_image template tag that have been passed through include by using the built-in Django filter add.

Example:

index.html

{% include 'partials/include.html' with image_name='logo' %}

include.html

{% with src="images/"|add:image_name|add:".jpg" %}
    {% optimized_image src=src %}
{% endwith %}

This will render:

<picture>
    <source srcset="/static/images/logo.webp" type="image/webp">
    <img src="/static/images/logo.jpg">
</picture>

Code Breakdown:

src is set to: src="images/

|add:image_name adds the image_name variable to the string, resulting in: src="images/logo

|add:".jpg" adds .jpg" to the string, resulting in: src="images/logo.jpg"