app/django/core/files/images.py
author Sverre Rabbelier <srabbelier@gmail.com>
Wed, 05 Nov 2008 23:32:59 +0000
changeset 443 94568ac6e3e1
parent 323 ff1a9aa48cfd
permissions -rw-r--r--
Implements base.Logic functions in home_settings, site_settings and work This patch implements the base.Logic funtions needed for making logic/key_name.py obsolete. This patch defines the needed functions in home_settings, site_settings and work. All modules in logic/models now have these functions defined. logic/models/site_settings.py now inherits from logic/models/home_settings.py because of their similar connection in the corresponding models. Please note that the self._keyName for these two modules still points to logic/key_name.py since entity_type is still used in views/home.py. A partial_path and link_name were added to HomeSettings as requested by SRabbelier.

"""
Utility functions for handling images.

Requires PIL, as you might imagine.
"""

from django.core.files import File

class ImageFile(File):
    """
    A mixin for use alongside django.core.files.base.File, which provides
    additional features for dealing with images.
    """
    def _get_width(self):
        return self._get_image_dimensions()[0]
    width = property(_get_width)

    def _get_height(self):
        return self._get_image_dimensions()[1]
    height = property(_get_height)

    def _get_image_dimensions(self):
        if not hasattr(self, '_dimensions_cache'):
            self._dimensions_cache = get_image_dimensions(self)
        return self._dimensions_cache

def get_image_dimensions(file_or_path):
    """Returns the (width, height) of an image, given an open file or a path."""
    from PIL import ImageFile as PILImageFile
    p = PILImageFile.Parser()
    if hasattr(file_or_path, 'read'):
        file = file_or_path
    else:
        file = open(file_or_path, 'rb')
    while 1:
        data = file.read(1024)
        if not data:
            break
        p.feed(data)
        if p.image:
            return p.image.size
    return None