Implement support for "Hellwig and Fairchild (2022) Colour Appearanc…

…e… … Model".

README.rst

@@ -338,6 +338,8 @@ Colour Appearance Models - ``colour.appearance``
     CAM_Specification_CIECAM02(J=34.434525727858997, C=67.365010921125943, h=22.279164147957065, s=62.81485585332716, Q=177.47124941102123, M=70.024939419291414, H=2.6896085344238898, HC=None)
     >>> colour.XYZ_to_CAM16(XYZ, XYZ_w, L_A, Y_b)
     CAM_Specification_CAM16(J=33.880368498111686, C=69.444353357408033, h=19.510887327451748, s=64.03612114840314, Q=176.03752758512178, M=72.18638534116765, H=399.52975599115319, HC=None)
+    >>> colour.XYZ_to_Hellwig2022(XYZ, XYZ_w, L_A)
+    CAM_Specification_Hellwig2022(J=33.880368498111686, C=40.347043294550311, h=19.510887327451748, s=117.38555017188679, Q=45.34489577734751, M=53.228355383108031, H=399.52975599115319, HC=None)
     >>> colour.XYZ_to_Kim2009(XYZ, XYZ_w, L_A)
     CAM_Specification_Kim2009(J=19.879918542450902, C=55.839055250876946, h=22.013388165090046, s=112.97979354939129, Q=36.309026130161449, M=46.346415858227864, H=2.3543198369639931, HC=None)
     >>> colour.XYZ_to_ZCAM(XYZ, XYZ_w, L_A, Y_b)

colour/__init__.py

@@ -146,6 +146,7 @@
     CAM_Specification_ATD95,
     CAM_Specification_CAM16,
     CAM_Specification_CIECAM02,
+    CAM_Specification_Hellwig2022,
     CAM_Specification_Hunt,
     CAM_Specification_Kim2009,
     CAM_Specification_LLAB,
@@ -155,12 +156,14 @@
     CAM16_to_XYZ,
     CIECAM02_to_XYZ,
     HKE_NAYATANI1997_METHODS,
+    Hellwig2022_to_XYZ,
     HelmholtzKohlrausch_effect_object_Nayatani1997,
     HelmholtzKohlrausch_effect_luminous_Nayatani1997,
     Kim2009_to_XYZ,
     MEDIA_PARAMETERS_KIM2009,
     VIEWING_CONDITIONS_CAM16,
     VIEWING_CONDITIONS_CIECAM02,
+    VIEWING_CONDITIONS_Hellwig2022,
     VIEWING_CONDITIONS_HUNT,
     VIEWING_CONDITIONS_KIM2009,
     VIEWING_CONDITIONS_LLAB,
@@ -170,6 +173,7 @@
     XYZ_to_CAM16,
     XYZ_to_CIECAM02,
     XYZ_to_Kim2009,
+    XYZ_to_Hellwig2022,
     XYZ_to_Hunt,
     XYZ_to_LLAB,
     XYZ_to_Nayatani95,
@@ -554,6 +558,7 @@ def __getattr__(self, attribute) -> Any:
     "CAM_Specification_ATD95",
     "CAM_Specification_CAM16",
     "CAM_Specification_CIECAM02",
+    "CAM_Specification_Hellwig2022",
     "CAM_Specification_Hunt",
     "CAM_Specification_Kim2009",
     "CAM_Specification_LLAB",
@@ -563,12 +568,14 @@ def __getattr__(self, attribute) -> Any:
     "CAM16_to_XYZ",
     "CIECAM02_to_XYZ",
     "HKE_NAYATANI1997_METHODS",
+    "Hellwig2022_to_XYZ",
     "HelmholtzKohlrausch_effect_object_Nayatani1997",
     "HelmholtzKohlrausch_effect_luminous_Nayatani1997",
     "Kim2009_to_XYZ",
     "MEDIA_PARAMETERS_KIM2009",
     "VIEWING_CONDITIONS_CAM16",
     "VIEWING_CONDITIONS_CIECAM02",
+    "VIEWING_CONDITIONS_Hellwig2022",
     "VIEWING_CONDITIONS_HUNT",
     "VIEWING_CONDITIONS_KIM2009",
     "VIEWING_CONDITIONS_LLAB",
@@ -578,6 +585,7 @@ def __getattr__(self, attribute) -> Any:
     "XYZ_to_CAM16",
     "XYZ_to_CIECAM02",
     "XYZ_to_Kim2009",
+    "XYZ_to_Hellwig2022",
     "XYZ_to_Hunt",
     "XYZ_to_LLAB",
     "XYZ_to_Nayatani95",

colour/appearance/__init__.py

@@ -20,6 +20,13 @@
     XYZ_to_CAM16,
     CAM16_to_XYZ,
 )
+from .hellwig2022 import (
+    InductionFactors_Hellwig2022,
+    VIEWING_CONDITIONS_Hellwig2022,
+    CAM_Specification_Hellwig2022,
+    XYZ_to_Hellwig2022,
+    Hellwig2022_to_XYZ,
+)
 from .hke import (
     HKE_NAYATANI1997_METHODS,
     HelmholtzKohlrausch_effect_object_Nayatani1997,
@@ -81,6 +88,13 @@
     "XYZ_to_CAM16",
     "CAM16_to_XYZ",
 ]
+__all__ += [
+    "InductionFactors_Hellwig2022",
+    "VIEWING_CONDITIONS_Hellwig2022",
+    "CAM_Specification_Hellwig2022",
+    "XYZ_to_Hellwig2022",
+    "Hellwig2022_to_XYZ",
+]
 __all__ += [
     "HKE_NAYATANI1997_METHODS",
     "HelmholtzKohlrausch_effect_object_Nayatani1997",