The image_variations Django application allows you to create different variations of uploaded images that can be used as thumbnails or for any another purposes.

You can install image_variations using pip:

pip install django-image-variations

Alternatively, you can install it from source:

git clone https://github.com/pisemsky/django-image-variations.git
cd django-image-variations
python setup.py install

After installing append image_variations to INSTALLED_APPS in your project settings file.

Variations defined by setting up variable IMAGE_VARIATIONS in Django project settings file. This is a dict where key is variation name and value is a tuple of 2-tuples. Each of that 2-tuples describes one of transforms that consequentially applied to the original image. The first element of each 2-tuple is a transform name that is method in transforms.py file and second element is a dict with keyword arguments to that method. Example configuration:

IMAGE_VARIATIONS = {
    'small': (
        ('crop', {'width': 120, 'height': 90}),
        ('save', {'quality': 90}),
    ),
    'large': (
        ('resize', {'width': 640}),
        ('save', {'quality': 90, 'progressive': True}),
    ),
}

Currently there are only two transforms implemented - resize and crop. There is also a special transform called save that allows you to specify image quality and another options suitable for PIL's Image.save method. This transfrom is not required, but if used, it must be last in tuple.

Application provides a field called ImageVariationsField that based on standard Django ImageField and performs all magic. Use this field in your models:

from image_variations.fields import ImageVariationsField

class Image(models.Model):
    image = ImageVariationsField(upload_to='images')

After that variations can be accessed as attributes of the image field like so:

object.image.small
object.image.small.name
object.image.small.width
object.image.small.height
object.image.small.path
object.image.small.url

Each variation represented by ImageFile instance with two additional attributes - path and url.