Add LCMS2 flags to ImageCms

Tests/test_imagecms.py

@@ -90,6 +90,16 @@ def test_sanity():
     hopper().point(t)
 
 
+def test_flags():
+    assert ImageCms.Flags.NONE == 0
+    assert ImageCms.Flags.GRIDPOINTS(0) == ImageCms.Flags.NONE
+    assert ImageCms.Flags.GRIDPOINTS(256) == ImageCms.Flags.NONE
+
+    assert ImageCms.Flags.GRIDPOINTS(255) == (255 << 16)
+    assert ImageCms.Flags.GRIDPOINTS(-1) == ImageCms.Flags.GRIDPOINTS(255)
+    assert ImageCms.Flags.GRIDPOINTS(511) == ImageCms.Flags.GRIDPOINTS(255)
+
+
 def test_name():
     skip_missing()
     # get profile information for file

docs/deprecations.rst

@@ -338,8 +338,8 @@ ImageCms.CmsProfile attributes
 .. deprecated:: 3.2.0
 .. versionremoved:: 8.0.0
 
-Some attributes in :py:class:`PIL.ImageCms.CmsProfile` have been removed. From 6.0.0,
-they issued a :py:exc:`DeprecationWarning`:
+Some attributes in :py:class:`PIL.ImageCms.core.CmsProfile` have been removed.
+From 6.0.0, they issued a :py:exc:`DeprecationWarning`:
 
 ========================  ===================================================
 Removed                   Use instead

docs/reference/ImageCms.rst

@@ -8,9 +8,31 @@ The :py:mod:`~PIL.ImageCms` module provides color profile management
 support using the LittleCMS2 color management engine, based on Kevin
 Cazabon's PyCMS library.
 
+.. autoclass:: ImageCmsProfile
+    :members:
+    :special-members: __init__
 .. autoclass:: ImageCmsTransform
+    :members:
+    :undoc-members:
+    :show-inheritance:
 .. autoexception:: PyCMSError
 
+Constants
+---------
+
+.. autoclass:: Intent
+    :members:
+    :member-order: bysource
+    :undoc-members:
+.. autoclass:: Direction
+    :members:
+    :member-order: bysource
+    :undoc-members:
+.. autoclass:: Flags
+    :members:
+    :member-order: bysource
+    :undoc-members:
+
 Functions
 ---------
 
@@ -37,13 +59,15 @@ CmsProfile
 ----------
 
 The ICC color profiles are wrapped in an instance of the class
-:py:class:`CmsProfile`.  The specification ICC.1:2010 contains more
+:py:class:`~core.CmsProfile`.  The specification ICC.1:2010 contains more
 information about the meaning of the values in ICC profiles.
 
 For convenience, all XYZ-values are also given as xyY-values (so they
 can be easily displayed in a chromaticity diagram, for example).
 
+.. py:currentmodule:: PIL.ImageCms.core
 .. py:class:: CmsProfile
+    :canonical: PIL._imagingcms.CmsProfile
 
     .. py:attribute:: creation_date
         :type: Optional[datetime.datetime]

docs/releasenotes/8.0.0.rst

@@ -30,7 +30,7 @@ Image.fromstring, im.fromstring and im.tostring
 ImageCms.CmsProfile attributes
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-Some attributes in :py:class:`PIL.ImageCms.CmsProfile` have been removed:
+Some attributes in :py:class:`PIL.ImageCms.core.CmsProfile` have been removed:
 
 ========================  ===================================================
 Removed                   Use instead

src/PIL/ImageCms.py

@@ -16,8 +16,10 @@
 # below for the original description.
 from __future__ import annotations
 
+import operator
 import sys
-from enum import IntEnum
+from enum import IntEnum, IntFlag
+from functools import reduce
 
 from . import Image
 
@@ -119,6 +121,69 @@
 #
 # flags
 
+
+class Flags(IntFlag):
+    """Flags and documentation are taken from ``lcms2.h``."""
+
+    NONE = 0
+    NOCACHE = 0x0040
+    """Inhibit 1-pixel cache"""
+    NOOPTIMIZE = 0x0100
+    """Inhibit optimizations"""
+    NULLTRANSFORM = 0x0200
+    """Don't transform anyway"""
+    GAMUTCHECK = 0x1000
+    """Out of Gamut alarm"""
+    SOFTPROOFING = 0x4000
+    """Do softproofing"""
+    BLACKPOINTCOMPENSATION = 0x2000
+    NOWHITEONWHITEFIXUP = 0x0004
+    """Don't fix scum dot"""
+    HIGHRESPRECALC = 0x0400
+    """Use more memory to give better accuracy"""
+    LOWRESPRECALC = 0x0800
+    """Use less memory to minimize resources"""
+    # this should be 8BITS_DEVICELINK, but that is not a valid name in Python:
+    USE_8BITS_DEVICELINK = 0x0008
+    """Create 8 bits devicelinks"""
+    GUESSDEVICECLASS = 0x0020
+    """Guess device class (for ``transform2devicelink``)"""
+    KEEP_SEQUENCE = 0x0080
+    """Keep profile sequence for devicelink creation"""
+    FORCE_CLUT = 0x0002
+    """Force CLUT optimization"""
+    CLUT_POST_LINEARIZATION = 0x0001
+    """create postlinearization tables if possible"""
+    CLUT_PRE_LINEARIZATION = 0x0010
+    """create prelinearization tables if possible"""
+    NONEGATIVES = 0x8000
+    """Prevent negative numbers in floating point transforms"""
+    COPY_ALPHA = 0x04000000
+    """Alpha channels are copied on ``cmsDoTransform()``"""
+    NODEFAULTRESOURCEDEF = 0x01000000
+
+    _GRIDPOINTS_1 = 1 << 16
+    _GRIDPOINTS_2 = 2 << 16
+    _GRIDPOINTS_4 = 4 << 16
+    _GRIDPOINTS_8 = 8 << 16
+    _GRIDPOINTS_16 = 16 << 16
+    _GRIDPOINTS_32 = 32 << 16
+    _GRIDPOINTS_64 = 64 << 16
+    _GRIDPOINTS_128 = 128 << 16
+
+    @staticmethod
+    def GRIDPOINTS(n: int) -> Flags:
+        """
+        Fine-tune control over number of gridpoints
+
+        :param n: :py:class:`int` in range ``0 <= n <= 255``
+        """
+        return Flags.NONE | ((n & 0xFF) << 16)
+
+
+_MAX_FLAG = reduce(operator.or_, Flags)
+
+
 FLAGS = {
     "MATRIXINPUT": 1,
     "MATRIXOUTPUT": 2,
@@ -142,11 +207,6 @@
     "GRIDPOINTS": lambda n: (n & 0xFF) << 16,  # Gridpoints
 }
 
-_MAX_FLAG = 0
-for flag in FLAGS.values():
-    if isinstance(flag, int):
-        _MAX_FLAG = _MAX_FLAG | flag
-
 
 # --------------------------------------------------------------------.
 # Experimental PIL-level API
@@ -218,7 +278,7 @@
         intent=Intent.PERCEPTUAL,
         proof=None,
         proof_intent=Intent.ABSOLUTE_COLORIMETRIC,
-        flags=0,
+        flags=Flags.NONE,
     ):
         if proof is None:
             self.transform = core.buildTransform(
@@ -303,7 +363,7 @@
     renderingIntent=Intent.PERCEPTUAL,
     outputMode=None,
     inPlace=False,
-    flags=0,
+    flags=Flags.NONE,
 ):
     """
     (pyCMS) Applies an ICC transformation to a given image, mapping from
@@ -420,7 +480,7 @@
     inMode,
     outMode,
     renderingIntent=Intent.PERCEPTUAL,
-    flags=0,
+    flags=Flags.NONE,
 ):
     """
     (pyCMS) Builds an ICC transform mapping from the ``inputProfile`` to the
@@ -482,7 +542,7 @@
         raise PyCMSError(msg)
 
     if not isinstance(flags, int) or not (0 <= flags <= _MAX_FLAG):
-        msg = "flags must be an integer between 0 and %s" + _MAX_FLAG
+        msg = f"flags must be an integer between 0 and {_MAX_FLAG}"
         raise PyCMSError(msg)
 
     try:
@@ -505,7 +565,7 @@
     outMode,
     renderingIntent=Intent.PERCEPTUAL,
     proofRenderingIntent=Intent.ABSOLUTE_COLORIMETRIC,
-    flags=FLAGS["SOFTPROOFING"],
+    flags=Flags.SOFTPROOFING,
 ):
     """
     (pyCMS) Builds an ICC transform mapping from the ``inputProfile`` to the
@@ -586,7 +646,7 @@
         raise PyCMSError(msg)
 
     if not isinstance(flags, int) or not (0 <= flags <= _MAX_FLAG):
-        msg = "flags must be an integer between 0 and %s" + _MAX_FLAG
+        msg = f"flags must be an integer between 0 and {_MAX_FLAG}"
         raise PyCMSError(msg)
 
     try: