+
−"""
+
−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