plugin XEP-0264: fix orientation of thumbnails:

Rotation of thumbnailis is now modified according to EXIF orientation data. Original image
is not modified as user may want to keep it, and orientation transformation can modify
encoding parameters.

Update `pillow` minimum version to the first one with `exif_transpose` implementation.

sat/plugins/plugin_xep_0264.py

@@ -34,7 +34,7 @@ from sat.core import exceptions
 import hashlib
 
 try:
-    from PIL import Image
+    from PIL import Image, ImageOps
 except:
     raise exceptions.MissingModule(
         "Missing module pillow, please download/install it from https://python-pillow.github.io"
@@ -138,7 +138,9 @@ class XEP_0264(object):
         """
         return hashlib.sha256(repr((image_uid, size)).encode()).hexdigest()
 
-    def _blockingGenThumb(self, source_path, size=None, max_age=None, image_uid=None):
+    def _blockingGenThumb(
+            self, source_path, size=None, max_age=None, image_uid=None,
+            fix_orientation=True):
         """Generate a thumbnail for image
 
         This is a blocking method and must be executed in a thread
@@ -152,16 +154,21 @@ class XEP_0264(object):
             return Failure(exceptions.DataError("Can't open image"))
 
         img.thumbnail(size)
+        if fix_orientation:
+            img = ImageOps.exif_transpose(img)
+
         uid = self.getThumbId(image_uid or source_path, size)
 
         with self.host.common_cache.cacheData(
             PLUGIN_INFO[C.PI_IMPORT_NAME], uid, MIME_TYPE, max_age
         ) as f:
             img.save(f, SAVE_FORMAT)
+            log.debug(f"fixed orientation for {f.name}")
 
         return img.size, uid
 
-    def generateThumbnail(self, source_path, size=None, max_age=None, image_uid=None):
+    def generateThumbnail(
+        self, source_path, size=None, max_age=None, image_uid=None, fix_orientation=True):
         """Generate a thumbnail of image
 
         @param source_path(unicode): absolute path to source image
@@ -172,13 +179,14 @@ class XEP_0264(object):
         @param image_uid(unicode, None): unique ID to identify the image
             use hash whenever possible
             if None, source_path will be used
+        @param fix_orientation(bool): if True, fix orientation using EXIF data
         @return D(tuple[tuple[int,int], unicode]): tuple with:
             - size of the thumbnail
             - unique Id of the thumbnail
         """
-
         d = threads.deferToThread(
-            self._blockingGenThumb, source_path, size, max_age, image_uid=image_uid
+            self._blockingGenThumb, source_path, size, max_age, image_uid=image_uid,
+            fix_orientation=fix_orientation
         )
         d.addErrback(
             lambda failure_: log.error("thumbnail generation error: {}".format(failure_))

setup.py

@@ -33,7 +33,7 @@ install_requires = [
     'miniupnpc',
     'mutagen',
     'netifaces',
-    'pillow',
+    'pillow >= 6.0.0',
     'progressbar2',
     'cryptography',
     'pygments',