Use EXIF info to fix orientation.

sigal/image.py

@@ -34,6 +34,10 @@ from PIL import Image as PILImage
 from PIL import ImageDraw, ImageOps
 
 
+# EXIF specs Orientation constant
+EXIF_ORIENTATION_TAG = 274
+
+
 class Image:
     """ Image container
 
@@ -48,6 +52,15 @@ class Image:
         self.imgname = os.path.split(filename)[1]
         self.img = PILImage.open(filename)
 
+        exif = self.img._getexif()
+        orientation = exif.get(EXIF_ORIENTATION_TAG)
+
+        # see: http://www.impulseadventure.com/photo/exif-orientation.html
+        rotate_map = {3: 180, 6: -90, 8: 90}
+        rotation = rotate_map.get(orientation)
+        if rotation:
+            self.img = self.img.rotate(rotation)
+
     def save(self, filename, quality=90):
         self.img.save(filename, quality=quality)