app/django/core/files/images.py
author Pawel Solyga <Pawel.Solyga@gmail.com>
Sun, 19 Oct 2008 21:12:08 +0000
changeset 394 4c60652a3947
parent 323 ff1a9aa48cfd
permissions -rw-r--r--
Add BaseForm class to soc.views.helper.forms module (work in progress). This changes the way as_table function displays the form (for more information have a look into doc string). BaseForm is going to be used for all forms in Melange in future. Right now it's still missing custom form errors labels and "required" text in 3rd column, but that's added as TODO and I'm working on it. Patch by: Pawel Solyga Review 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