django-thumbs

Create thumbnails for your images with Django.

Fork

Forked from https://code.google.com/p/django-thumbs/.

Features

• Easy to integrate in your code (no database changes, works as an ImageField)
• Works with any storage backend
• Generates thumbnails after image is uploaded into memory
• Deletes thumbnails when the image file is deleted
• Provides easy access to the thumbnails' URLs (similar method as with ImageField)

Example

from django.db import models
from thumbs.fields import ImageThumbsField

class Person(models.Model):

    SIZES = (
        {'code': 'avatar', 'wxh': '125x125', 'resize': 'crop'},
        {'code': 'm', 'wxh': '640x480', 'resize': 'scale'},
        {'code': '150', 'wxh': '150x150'},  # 'resize' defaults to 'scale'
    )
    photo = ImageThumbsField(upload_to='images', sizes=SIZES)

The field photo has a sizes attribute specifying desired sizes for the thumbnails. This field works the same way as ImageField but it also creates the desired thumbnails when uploading a new file and deletes the thumbnails when deleting the file.

With ImageThumbsField you retrieve the URL for every thumbnail specifying its size code. In this example we use someone.photo.url_avatar, someone.photo.url_150 or someone.photo.url_m to get the thumbnail URL.

Install

Install django-thumbs into a virtualenv using pip:

(env)$ pip install -e git+https://github.com/brettstil/django-thumbs.git#egg=django-thumbs

Add thumbs to your installed apps:

INSTALLED_APPS = (
    # ...
    'thumbs',
)

Usage

• Import it in your models.py and replace ImageField with ImageThumbsField in your model
• Add a sizes attribute with a list of sizes you want to use for the thumbnails
• Make sure you have defined STATIC_URL in your settings.py

Sizes

Each size is a dictionary that defines a thumbnail. For example,

SIZES = (
    {'code': 'avatar', 'wxh': '125x125', 'resize': 'crop'},
    {'code': 'm', 'wxh': '640x480', 'resize': 'scale'},
    {'code': 'flatrow', 'wxh': 'x120'},
    {'code': '150', 'wxh': '150x150'},  # 'resize' defaults to 'scale'
)

Size validation errors will raise SizeError.

code (required)

matches re: RE_CODE

code is the size name. It appears in the thumb filename separated by THUMBS_DELIMITER. For example, 'original.jpg' becomes 'original-small.jpg' for the default delimiter '-' and code 'small'.

wxh (required)

matches re: RE_WXH

wxh is the width x height as a string.

Fixed width images are supported with 240x. The thumbnail will be scaled down or up to a 240 pixel width. Fixed height images are similarly supported with 90x.

resize (optional)

default: 'scale' options: 'scale' or 'crop'

resize determines how the image will be resized.

'scale' resizes the thumb to wxh. For example, a 2000 x 1000 image will become 500 x 250 for 'scale' and a wxh of '500x500'. 'scale' does not enlarge a photo. A 200 x 100 image will remain 200 x 100 for 'scale' and wxh of '500x500'. 'scale' does not crop.

'crop' crops and centers the image fit wxh exactly. For example, a 2000 x 1000 image will become 500 x 500 for 'crop' and a wxh of '500x500'. 'crop' will enlarge a photo to exactly fit wxh. A 200 x 100 image will enlarge and crop to 500 x 500 for 'crop' and wxh of '500x500'.

Settings

django-thumbs will use default settings unless these settings are found in Django settings.

THUMBS_DELIMITER

default: '-'

THUMBS_DELIMITER sets the delimiter between the original image base name and the thumb size code. For example, 'original.jpg' becomes 'original-small.jpg' for the default delimiter '-' and code 'small'.

THUMBS_JPG

default: False

Set THUMBS_JPG to True to force all thumbnails to .jpg format and file extension regardless of original image format or file extension.

THUMBS_QUALITY

default: 75

THUMBS_QUALITY sets PIL quality. See http://www.pythonware.com/library/pil/handbook/format-jpeg.htm

THUMBS_OPTIMIZE

default: True

THUMBS_OPTIMIZE sets PIL optimize option on JPG or PNG images.

THUMBS_PROGRESSIVE

default: False

THUMBS_PROGRESSIVE sets PIL progressive option on JPG images.

THUMBS_AUTOROTATE

default: True

THUMBS_AUTOROTATE rotates thumbnails based on original EXIF data, if any.

PublicS3BotoStorage

PublicS3BotoStorage generates clean URLs for Amazon S3 in code--without calling Amazon and without S3 querystring auth and expires. Hooray! URLs are 'public-read'.

PublicS3BotoStorage is based on S3BotoStorage_AllPublic from https://github.com/duointeractive/django-athumb.

Add to requirements.txt:

django-storages==1.1.4
boto==2.5.2

In Django settings, instead of

DEFAULT_FILE_STORAGE = 'storages.backends.s3boto.S3BotoStorage'

use PublicS3BotoStorage:

DEFAULT_FILE_STORAGE = 'thumbs.backends.PublicS3BotoStorage'

PublicS3BotoStorage looks for AWS_S3_SECURE_URLS and AWS_S3_CUSTOM_DOMAIN settings. AWS_S3_SECURE_URLS sets https or http. AWS_S3_CUSTOM_DOMAIN sets custom domain or s3.amazonaws.com.

Uninstall

At any time you can go back and use ImageField again without altering the database or anything else. Just replace ImageThumbsField with ImageField again and make sure you delete the sizes attribute. Everything will work the same way it worked before using django-thumbs. Just remember to delete generated thumbnails in the case you don't want to have them anymore.