From 4fa160259deaeca196453947ba62bc319b6bf151 Mon Sep 17 00:00:00 2001
From: mara004 <geisserml@gmail.com>
Date: Sun, 25 Aug 2024 17:52:38 +0200
Subject: [PATCH] Slightly simplify the getexif procedure

No need for a loop here either.
Note that you could also use a dictionary rather than an if-elif tree
for the value -> rotation mapping (where valid/supported).
---
 src/img2pdf.py | 73 +++++++++++++++++++++++++-------------------------
 1 file changed, 37 insertions(+), 36 deletions(-)

diff --git a/src/img2pdf.py b/src/img2pdf.py
index f89670b..f219fdb 100755
--- a/src/img2pdf.py
+++ b/src/img2pdf.py
@@ -22,7 +22,7 @@ import sys
 import os
 import zlib
 import argparse
-from PIL import Image, TiffImagePlugin, GifImagePlugin, ImageCms
+from PIL import Image, TiffImagePlugin, GifImagePlugin, ImageCms, ExifTags
 
 if hasattr(GifImagePlugin, "LoadingStrategy"):
     # Pillow 9.0.0 started emitting all frames but the first as RGB instead of
@@ -1372,41 +1372,42 @@ def get_imgmetadata(
 
     rotation = 0
     if rotreq in (None, Rotation.auto, Rotation.ifvalid):
-        if hasattr(imgdata, "_getexif") and imgdata._getexif() is not None:
-            for tag, value in imgdata._getexif().items():
-                if TAGS.get(tag, tag) == "Orientation":
-                    # Detailed information on EXIF rotation tags:
-                    # http://impulseadventure.com/photo/exif-orientation.html
-                    if value == 1:
-                        rotation = 0
-                    elif value == 6:
-                        rotation = 90
-                    elif value == 3:
-                        rotation = 180
-                    elif value == 8:
-                        rotation = 270
-                    elif value in (2, 4, 5, 7):
-                        if rotreq == Rotation.ifvalid:
-                            logger.warning(
-                                "Unsupported flipped rotation mode (%d): use "
-                                "--rotation=ifvalid or "
-                                "rotation=img2pdf.Rotation.ifvalid to ignore",
-                                value,
-                            )
-                        else:
-                            raise ExifOrientationError(
-                                "Unsupported flipped rotation mode (%d): use "
-                                "--rotation=ifvalid or "
-                                "rotation=img2pdf.Rotation.ifvalid to ignore" % value
-                            )
-                    else:
-                        if rotreq == Rotation.ifvalid:
-                            logger.warning("Invalid rotation (%d)", value)
-                        else:
-                            raise ExifOrientationError(
-                                "Invalid rotation (%d): use --rotation=ifvalid "
-                                "or rotation=img2pdf.Rotation.ifvalid to ignore" % value
-                            )
+        exif_dict = imgdata.getexif()
+        o_key = ExifTags.Base.Orientation.value  # 274 rsp. 0x112
+        if exif_dict and o_key in exif_dict:
+            # Detailed information on EXIF rotation tags:
+            # http://impulseadventure.com/photo/exif-orientation.html
+            value = exif_dict[o_key]
+            if value == 1:
+                rotation = 0
+            elif value == 6:
+                rotation = 90
+            elif value == 3:
+                rotation = 180
+            elif value == 8:
+                rotation = 270
+            elif value in (2, 4, 5, 7):
+                if rotreq == Rotation.ifvalid:
+                    logger.warning(
+                        "Unsupported flipped rotation mode (%d): use "
+                        "--rotation=ifvalid or "
+                        "rotation=img2pdf.Rotation.ifvalid to ignore",
+                        value,
+                    )
+                else:
+                    raise ExifOrientationError(
+                        "Unsupported flipped rotation mode (%d): use "
+                        "--rotation=ifvalid or "
+                        "rotation=img2pdf.Rotation.ifvalid to ignore" % value
+                    )
+            else:
+                if rotreq == Rotation.ifvalid:
+                    logger.warning("Invalid rotation (%d)", value)
+                else:
+                    raise ExifOrientationError(
+                        "Invalid rotation (%d): use --rotation=ifvalid "
+                        "or rotation=img2pdf.Rotation.ifvalid to ignore" % value
+                    )
     elif rotreq in (Rotation.none, Rotation["0"]):
         rotation = 0
     elif rotreq == Rotation["90"]: