1 files changed, 42 insertions, 0 deletions
diff --git a/webapp/django/core/files/images.py b/webapp/django/core/files/images.py
new file mode 100644
index 0000000000..5ddcdd4322
--- /dev/null
+++ b/webapp/django/core/files/images.py
@@ -0,0 +1,42 @@
+"""
+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