app/django/core/files/images.py
author Lennard de Rijk <ljvderijk@gmail.com>
Thu, 05 Feb 2009 22:15:38 +0000
changeset 1225 1d5c58e24fd3
parent 323 ff1a9aa48cfd
permissions -rw-r--r--
Org applications can now only be made by a user when a program allows it. To do this a new access_type has been added called apply. This ensures that users can only used the seeded version of create. Also the review_overview now has his own access type to ensure the separability of hosts for different sponsors in case of org app reviews. Note that the access checks for hosts are broken and only give access to developers at the moment. Patch by: Lennard de Rijk Reviewed by: to-be-reviewed

"""
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