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Updated Filter to resize a ImageField on demand (ver.2)

Author:
rawjam
Posted:
January 25, 2010
Language:
Python
Version:
1.1
Tags:
image templatetag thumbnail resize imagefield
Score:
2 (after 2 ratings)

An update to snippet 1718 (http://www.djangosnippets.org/snippets/1718/). This update lets you pass an image URL string as well as a model ImageField instance. This means that you can then create thumbnails on demand for images outside of model

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import os
import Image
from django.template import Library

register = Library()

def thumbnail(file, size='200x200'):
    """
    Example:
    <img src="object.get_image_url" alt="original image" />
    <img src="object.image|thumbnail" alt="image resized to default 200x200 format" />
    <img src="object.image|thumbnail:"200x300" alt="image resized to 200x300" />

    The filter is applied to a image field (not the image url get from
    get_image_url method of the model), supposing the image filename is
    "image.jpg", it checks if there is a file called "image_200x200.jpg" or
    "image_200x300.jpg" on the second case, if the file isn't there, it resizes
    the original image, finally it returns the proper url to the resized image.
    """
    
    path = ""
    url = ""
    
    if type(file) == str:
        path = "%s/%s" % (settings.MEDIA_ROOT, file)
        url = "%s%s" % (settings.MEDIA_URL, file)
    elif file:
        path = file.path
        url = file.url
    
    if file:
        # defining the size
        x, y = [int(x) for x in size.split('x')]
        # defining the filename and the miniature filename
        basename, format = path.rsplit('.', 1)
        baseurl, _format = url.rsplit('.', 1)

        miniature_filename = basename + '_' + size + '.' +  format
        miniature_url = baseurl + '_' + size + '.' +  format

        # if the image wasn't already resized, resize it
        if not os.path.exists(miniature_filename):
            image = Image.open(path)
            image.thumbnail([x, y])
            image.save(miniature_filename, image.format)
        print miniature_url
        return miniature_url

    return ''

register.filter(thumbnail)

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  1. [UPDATE]Filter to resize a ImageField on demand by rafacdb 6 years, 8 months ago
  2. Updated Filter to resize a ImageField on demand by gmandx 5 years, 7 months ago
  3. Filter to resize a ImageField on demand by michelts 8 years ago
  4. [UPDATE]Filter to resize a ImageField on demand + RATIO OPTION + CLEANUP by karlsberg 4 years, 8 months ago
  5. Download an image using requests, resize it using PIL, and save it to a model ImageField. by stewx 1 month ago

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