changeset 3332:1512cbd6c4ac

tools (image): fix_orientation on resize + `fix_orientation` method: a new argument (`True` by default) fix orientation (i.e. rotate according to EXIF data) of image when resizing it. A new `fix_orientation` method (unused for now) let do it independently
author Goffi <goffi@goffi.org>
date Thu, 13 Aug 2020 23:46:18 +0200
parents b1e9f17fbb5a
children ac9342f359e9
files sat/tools/image.py
diffstat 1 files changed, 33 insertions(+), 6 deletions(-) [+]
line wrap: on
line diff
--- a/sat/tools/image.py	Thu Aug 13 23:46:18 2020 +0200
+++ b/sat/tools/image.py	Thu Aug 13 23:46:18 2020 +0200
@@ -20,7 +20,7 @@
 
 import tempfile
 import mimetypes
-from PIL import Image
+from PIL import Image, ImageOps
 from pathlib import Path
 from twisted.internet import threads
 from sat.core.i18n import _
@@ -69,10 +69,12 @@
     return report
 
 
-def _resizeBlocking(image_path, new_size, dest):
+def _resize_blocking(image_path, new_size, dest, fix_orientation):
     im_path = Path(image_path)
     im = Image.open(im_path)
     resized = im.resize(new_size, Image.LANCZOS)
+    if fix_orientation:
+        resized = ImageOps.fix_orientation(resized)
 
     if dest is None:
         dest = tempfile.NamedTemporaryFile(suffix=im_path.suffix, delete=False)
@@ -85,7 +87,7 @@
     return Path(f.name)
 
 
-def resize(image_path, new_size, dest=None):
+def resize(image_path, new_size, dest=None, fix_orientation=True):
     """Resize an image to a new file, and return its path
 
     @param image_path(str, Path): path of the original image
@@ -95,13 +97,15 @@
             file will be converted to PNG
         - Path: path to the file to create/overwrite
         - file: a file object which must be opened for writing in binary mode
+    @param fix_orientation: if True, use EXIF data to set orientation
     @return (Path): path of the resized file.
         The image at this path should be deleted after use
     """
-    return threads.deferToThread(_resizeBlocking, image_path, new_size, dest)
+    return threads.deferToThread(
+        _resize_blocking, image_path, new_size, dest, fix_orientation)
 
 
-def _convertBlocking(image_path, dest, extra):
+def _convert_blocking(image_path, dest, extra):
     media_type = mimetypes.guess_type(str(image_path), strict=False)[0]
 
     if dest is None:
@@ -173,7 +177,30 @@
         raise ValueError(f"There is no file at {image_path}!")
     if extra is None:
         extra = {}
-    return threads.deferToThread(_convertBlocking, image_path, dest, extra)
+    return threads.deferToThread(_convert_blocking, image_path, dest, extra)
+
+
+def __fix_orientation_blocking(image_path):
+    im = Image.open(image_path)
+    im_format = im.format
+    exif = im.getexif()
+    orientation = exif.get(0x0112)
+    if orientation is None or orientation<2:
+        # nothing to do
+        return False
+    im = ImageOps.exif_transpose(im)
+    im.save(image_path, im_format)
+    log.debug(f"image {image_path} orientation has been fixed")
+    return True
+
+
+def fix_orientation(image_path: Path) -> bool:
+    """Apply orientation found in EXIF data if any
+
+    @param image_path: image location, image will be modified in place
+    @return True if image has been modified
+    """
+    return threads.deferToThread(__fix_orientation_blocking, image_path)
 
 
 def guess_type(source):