remove all exif tags but a few

[django-panik-emissions.git] / emissions / utils.py

diff --git a/emissions/utils.py b/emissions/utils.py
index 7f3b9318d7d9bd2497374b19888f2d6b052e7a9f..5c647293b82f224888fba29404608e51b55690c2 100644 (file)
--- a/emissions/utils.py
+++ b/emissions/utils.py
@@ -6,7 +6,7 @@ from datetime import datetime, time, timedelta
 import piexif
 import taggit.utils
 from django.utils.encoding import force_str
-from PIL import Image
+from PIL import ExifTags, Image
 
 from .app_settings import app_settings
 
@@ -56,15 +56,29 @@ def maybe_resize(image_path):
 
     if 'exif' in image.info:
         exif_dict = piexif.load(image.info['exif'])
-        if 0x9208 in exif_dict.get('Exif', {}):
-            # remove LightSource exif data as it's corrupt on some motorola phones
-            del exif_dict['Exif'][0x9208]
+        if exif_dict.get('GPS'):
+            exif_dict['GPS'] = {}
+            save_image = True
+        if 'thumbnail' in exif_dict:
+            del exif_dict['thumbnail']
+            save_image = True
+        for ifd in list(exif_dict.get('Exif', {}).keys()):
+            # remove all tags except width/height/orientation
+            # this is because some phone/apps create bogus metadata
+            # that would break basic things like rotation.
+            if ifd not in (
+                ExifTags.Base.ExifImageWidth,
+                ExifTags.Base.ExifImageHeight,
+                ExifTags.Base.Orientation,
+            ):
+                del exif_dict['Exif'][ifd]
+                save_image = True
+        if save_image:
             try:
                 kwargs = {'exif': piexif.dump(exif_dict)}
             except ValueError:
                 # really broken content, remove it all
                 kwargs = {'exif': piexif.dump({})}
-            save_image = True
 
     if max(image.size) > 1400:
         # no sense storing images that large