Rewrite rejpg with argparse and preserve exif orientation.

rejpg.py

@@ -1,29 +1,35 @@
 '''
 Recompress all jpg images in the current directory.
-Add /r to do nested directories as well.
 '''
-
-from voussoirkit import bytestring
+import argparse
 import io
 import os
+import PIL.ExifTags
 import PIL.Image
 import PIL.ImageFile
 import string
 import sys
 
+from voussoirkit import bytestring
+
 PIL.ImageFile.LOAD_TRUNCATED_IMAGES = True
 
-if '/r' in sys.argv:
+for (ORIENTATION_KEY, val) in PIL.ExifTags.TAGS.items():
+    if val == 'Orientation':
+        break
+
+def rejpg_argparse(args):
+    if args.recurse:
         from voussoirkit import spinal
         walker = spinal.walk_generator()
         files = list(walker)
-    files = [f.absolute_path for f in files]
-
     else:
-    files = os.listdir()
-    files = [f for f in files if os.path.isfile(f)]
+        from voussoirkit import pathclass
+        files = pathclass.cwd().listdir()
+        files = [f for f in files if f.is_file]
 
-files = [f for f in files if any(ext in f.lower() for ext in ['.jpg', '.jpeg'])]
+    files = [f for f in files if f.extension in ['.jpg', '.jpeg']]
+    files = [f.absolute_path for f in files]
 
     bytes_saved = 0
     remaining_size = 0
@@ -31,6 +37,20 @@ for filename in files:
         print(''.join(c for c in filename if c in string.printable))
         bytesio = io.BytesIO()
         i = PIL.Image.open(filename)
+        exif = i._getexif()
+
+        # Preserve orientation according to exif
+        # Thank you Scabbiaza
+        # https://stackoverflow.com/a/26928142
+        if exif is None:
+            pass
+        elif exif[ORIENTATION_KEY] == 3:
+            i = i.rotate(180, expand=True)
+        elif exif[ORIENTATION_KEY] == 6:
+            i = i.rotate(270, expand=True)
+        elif exif[ORIENTATION_KEY] == 8:
+            i = i.rotate(90, expand=True)
+
         i.save(bytesio, format='jpeg', quality=80)
 
         bytesio.seek(0)
@@ -46,3 +66,15 @@ for filename in files:
 
     print('Saved', bytestring.bytestring(bytes_saved))
     print('Remaining are', bytestring.bytestring(remaining_size))
+
+def main(argv):
+    parser = argparse.ArgumentParser(description=__doc__)
+
+    parser.add_argument('--recurse', dest='recurse', action='store_true')
+    parser.set_defaults(func=rejpg_argparse)
+
+    args = parser.parse_args(argv)
+    return args.func(args)
+
+if __name__ == '__main__':
+    raise SystemExit(main(sys.argv[1:]))