Removed support for LibTIFF < 4

Tests/test_file_libtiff.py

@@ -256,19 +256,7 @@ class TestFileLibTiff(LibTiffTestCase):
 
             im.save(out, tiffinfo=new_ifd)
 
-    @pytest.mark.parametrize(
-        "libtiff",
-        (
-            pytest.param(
-                True,
-                marks=pytest.mark.skipif(
-                    not getattr(Image.core, "libtiff_support_custom_tags", False),
-                    reason="Custom tags not supported by older libtiff",
-                ),
-            ),
-            False,
-        ),
-    )
+    @pytest.mark.parametrize("libtiff", (True, False))
     def test_custom_metadata(
         self, monkeypatch: pytest.MonkeyPatch, tmp_path: Path, libtiff: bool
     ) -> None:
@@ -724,7 +712,6 @@ class TestFileLibTiff(LibTiffTestCase):
 
         with Image.open(out) as reloaded:
             assert isinstance(reloaded, TiffImagePlugin.TiffImageFile)
-            if Image.core.libtiff_support_custom_tags:
             assert reloaded.tag_v2[34665] == 125456
 
     def test_crashing_metadata(
@@ -777,19 +764,7 @@ class TestFileLibTiff(LibTiffTestCase):
             assert icc_libtiff is not None
         assert icc == icc_libtiff
 
-    @pytest.mark.parametrize(
-        "libtiff",
-        (
-            pytest.param(
-                True,
-                marks=pytest.mark.skipif(
-                    not getattr(Image.core, "libtiff_support_custom_tags", False),
-                    reason="Custom tags not supported by older libtiff",
-                ),
-            ),
-            False,
-        ),
-    )
+    @pytest.mark.parametrize("libtiff", (True, False))
     def test_write_icc(
         self, monkeypatch: pytest.MonkeyPatch, tmp_path: Path, libtiff: bool
     ) -> None:

docs/deprecations.rst

@@ -77,14 +77,6 @@ The use in :py:mod:`.ImageCms` of input modes and output modes that are not Pill
 image modes has been deprecated. Defaulting to "L" or "1" if the mode cannot be mapped
 is also deprecated.
 
-Support for LibTIFF earlier than 4
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-.. deprecated:: 10.4.0
-
-Support for LibTIFF earlier than version 4 has been deprecated.
-Upgrade to a newer version of LibTIFF instead.
-
 ImageDraw.getdraw hints parameter
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
@@ -194,6 +186,15 @@ BGR;15, BGR 16 and BGR;24
 
 The experimental BGR;15, BGR;16 and BGR;24 modes have been removed.
 
+Support for LibTIFF earlier than 4
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. deprecated:: 10.4.0
+.. versionremoved:: 12.0.0
+
+Support for LibTIFF earlier than version 4 has been removed.
+Upgrade to a newer version of LibTIFF instead.
+
 Image isImageType()
 ^^^^^^^^^^^^^^^^^^^
 

src/PIL/TiffImagePlugin.py

@@ -56,7 +56,6 @@ from . import ExifTags, Image, ImageFile, ImageOps, ImagePalette, TiffTags
 from ._binary import i16be as i16
 from ._binary import i32be as i32
 from ._binary import o8
-from ._deprecate import deprecate
 from ._typing import StrOrBytesPath
 from ._util import DeferredError, is_path
 from .TiffTags import TYPES
@@ -284,9 +283,6 @@ PREFIXES = [
     b"II\x2b\x00",  # BigTIFF with little-endian byte order
 ]
 
-if not getattr(Image.core, "libtiff_support_custom_tags", True):
-    deprecate("Support for LibTIFF earlier than version 4", 12)
-
 
 def _accept(prefix: bytes) -> bool:
     return prefix.startswith(tuple(PREFIXES))
@@ -1934,9 +1930,6 @@ def _save(im: Image.Image, fp: IO[bytes], filename: str | bytes) -> None:
             # Custom items are supported for int, float, unicode, string and byte
             # values. Other types and tuples require a tagtype.
             if tag not in TiffTags.LIBTIFF_CORE:
-                if not getattr(Image.core, "libtiff_support_custom_tags", False):
-                    continue
-
                 if tag in TiffTags.TAGS_V2_GROUPS:
                     types[tag] = TiffTags.LONG8
                 elif tag in ifd.tagtype:

src/_imaging.c

@@ -4352,16 +4352,6 @@ setup_module(PyObject *m) {
         PyObject *v = PyUnicode_FromString(ImagingTiffVersion());
         PyDict_SetItemString(d, "libtiff_version", v ? v : Py_None);
         Py_XDECREF(v);
-
-        // Test for libtiff 4.0 or later, excluding libtiff 3.9.6 and 3.9.7
-        PyObject *support_custom_tags;
-#if TIFFLIB_VERSION >= 20111221 && TIFFLIB_VERSION != 20120218 && \
-    TIFFLIB_VERSION != 20120922
-        support_custom_tags = Py_True;
-#else
-        support_custom_tags = Py_False;
-#endif
-        PyDict_SetItemString(d, "libtiff_support_custom_tags", support_custom_tags);
     }
 #endif
 

src/libImaging/TiffDecode.c

@@ -884,7 +884,6 @@ ImagingLibTiffMergeFieldInfo(
     // Refer to libtiff docs (http://www.simplesystems.org/libtiff/addingtags.html)
     TIFFSTATE *clientstate = (TIFFSTATE *)state->context;
     uint32_t n;
-    int status = 0;
 
     // custom fields added with ImagingLibTiffMergeFieldInfo are only used for
     // decoding, ignore readcount;
@@ -907,14 +906,7 @@ ImagingLibTiffMergeFieldInfo(
 
     n = sizeof(info) / sizeof(info[0]);
 
-    // Test for libtiff 4.0 or later, excluding libtiff 3.9.6 and 3.9.7
-#if TIFFLIB_VERSION >= 20111221 && TIFFLIB_VERSION != 20120218 && \
-    TIFFLIB_VERSION != 20120922
-    status = TIFFMergeFieldInfo(clientstate->tiff, info, n);
-#else
-    TIFFMergeFieldInfo(clientstate->tiff, info, n);
-#endif
-    return status;
+    return TIFFMergeFieldInfo(clientstate->tiff, info, n);
 }
 
 int