Allow encoderconfig and encoderinfo to be set for appended TIFF images

Tests/test_file_tiff.py

@@ -661,6 +661,18 @@ class TestFileTiff:
             assert isinstance(im, TiffImagePlugin.TiffImageFile)
             assert im.tag_v2[278] == 256
 
+        im = hopper()
+        im2 = Image.new("L", (128, 128))
+        im2.encoderinfo = {"tiffinfo": {278: 256}}
+        im.save(outfile, save_all=True, append_images=[im2])
+
+        with Image.open(outfile) as im:
+            assert isinstance(im, TiffImagePlugin.TiffImageFile)
+            assert im.tag_v2[278] == 128
+
+            im.seek(1)
+            assert im.tag_v2[278] == 256
+
     def test_strip_raw(self) -> None:
         infile = "Tests/images/tiff_strip_raw.tif"
         with Image.open(infile) as im:

docs/handbook/image-file-formats.rst

@@ -1162,9 +1162,7 @@ The :py:meth:`~PIL.Image.Image.save` method can take the following keyword argum
 
 **append_images**
     A list of images to append as additional frames. Each of the
-    images in the list can be single or multiframe images. Note however, that for
-    correct results, all the appended images should have the same
-    ``encoderinfo`` and ``encoderconfig`` properties.
+    images in the list can be single or multiframe images.
 
     .. versionadded:: 4.2.0
 

src/PIL/TiffImagePlugin.py

@@ -2295,9 +2295,7 @@ class AppendingTiffWriter(io.BytesIO):
 
 
 def _save_all(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
-    encoderinfo = im.encoderinfo.copy()
-    encoderconfig = im.encoderconfig
-    append_images = list(encoderinfo.get("append_images", []))
+    append_images = list(im.encoderinfo.get("append_images", []))
     if not hasattr(im, "n_frames") and not append_images:
         return _save(im, fp, filename)
 
@@ -2305,12 +2303,11 @@ def _save_all(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
     try:
         with AppendingTiffWriter(fp) as tf:
             for ims in [im] + append_images:
-                ims.encoderinfo = encoderinfo
-                ims.encoderconfig = encoderconfig
-                if not hasattr(ims, "n_frames"):
-                    nfr = 1
-                else:
-                    nfr = ims.n_frames
+                if not hasattr(ims, "encoderinfo"):
+                    ims.encoderinfo = {}
+                if not hasattr(ims, "encoderconfig"):
+                    ims.encoderconfig = ()
+                nfr = getattr(ims, "n_frames", 1)
 
                 for idx in range(nfr):
                     ims.seek(idx)