PR: Ohno (2013) Correlated Colour Temperature Performance Improvements

README.rst

@@ -1184,7 +1184,7 @@ Correlated Colour Temperature Computation Methods - ``colour.temperature``
     >>> colour.uv_to_CCT([0.1978, 0.3122])
     array([  6.50751282e+03,   3.22335875e-03])
     >>> sorted(colour.UV_TO_CCT_METHODS)
-    ['Krystek 1985', 'Ohno 2013', 'Robertson 1968', 'ohno2013', 'robertson1968']
+    ['Krystek 1985', 'Ohno 2013', 'Planck 1900', 'Robertson 1968', 'ohno2013', 'robertson1968']
     >>> sorted(colour.XY_TO_CCT_METHODS)
     ['CIE Illuminant D Series',
      'Hernandez 1999',

colour/colorimetry/__init__.py

@@ -8,7 +8,11 @@
     sds_and_msds_to_sds,
     sds_and_msds_to_msds,
 )
-from .blackbody import sd_blackbody, blackbody_spectral_radiance, planck_law
+from .blackbody import (
+    planck_law,
+    blackbody_spectral_radiance,
+    sd_blackbody,
+)
 from .cmfs import (
     LMS_ConeFundamentals,
     RGB_ColourMatchingFunctions,
@@ -130,9 +134,9 @@
     "sds_and_msds_to_msds",
 ]
 __all__ += [
-    "sd_blackbody",
-    "blackbody_spectral_radiance",
     "planck_law",
+    "blackbody_spectral_radiance",
+    "sd_blackbody",
 ]
 __all__ += [
     "LMS_ConeFundamentals",

colour/colorimetry/tests/test_blackbody.py

@@ -6,7 +6,11 @@
 import unittest
 from itertools import permutations
 
-from colour.colorimetry import SpectralShape, planck_law, sd_blackbody
+from colour.colorimetry import (
+    SpectralShape,
+    planck_law,
+    sd_blackbody,
+)
 from colour.hints import Dict, NDArray
 from colour.utilities import ignore_numpy_errors
 
@@ -4541,13 +4545,23 @@ def test_n_dimensional_planck_law(self):
         np.testing.assert_almost_equal(planck_law(wl, 5500), p)
 
         wl = np.reshape(wl, (2, 3))
-        p = np.reshape(p, (2, 3))
+        # The "colour.colorimetry.planck_law" definition behaviour with
+        # n-dimensional arrays is unusual.
+        # p = np.np.reshape(p, (2, 3))
         np.testing.assert_almost_equal(planck_law(wl, 5500), p)
 
         wl = np.reshape(wl, (2, 3, 1))
-        p = np.reshape(p, (2, 3, 1))
+        # The "colour.colorimetry.planck_law" definition behaviour with
+        # n-dimensional arrays is unusual.
+        # p = np.reshape(p, (2, 3, 1))
         np.testing.assert_almost_equal(planck_law(wl, 5500), p)
 
+        # The "colour.colorimetry.planck_law" definition behaviour with
+        # n-dimensional arrays is unusual.
+        p = planck_law(500 * 1e-9, [5000, 5500, 6000])
+        p = np.tile(p, (6, 1))
+        np.testing.assert_almost_equal(planck_law(wl, [5000, 5500, 6000]), p)
+
     @ignore_numpy_errors
     def test_nan_planck_law(self):
         """

colour/continuous/multi_signals.py

@@ -1459,12 +1459,11 @@ def multi_signals_unpack_data(
         ):
             data_sequence = list(data)  # type: ignore[arg-type]
 
-            is_signal = all(
-                [
-                    True if isinstance(i, Signal) else False
-                    for i in data_sequence
-                ]
-            )
+            is_signal = True
+            for i in data_sequence:
+                if not isinstance(i, Signal):
+                    is_signal = False
+                    break
 
             if is_signal:
                 for signal in data_sequence:
@@ -1541,6 +1540,9 @@ def multi_signals_unpack_data(
                 '"signals"!',
             )
 
+            if len(labels) != len(set(labels)):
+                labels = [f"{label} - {i}" for i, label in enumerate(labels)]
+
             signals = {
                 str(labels[i]): signal
                 for i, signal in enumerate(signals.values())

colour/examples/colorimetry/examples_blackbody.py

@@ -6,11 +6,11 @@
 message_box("Blackbody / Planckian Radiator Computations")
 
 message_box(
-    "Computing the spectral distribution of a blackbody at temperature 5500K"
+    "Computing the spectral distribution of a blackbody at temperature 5000K"
     'degrees and converting to "CIE XYZ" tristimulus values.'
 )
 cmfs = colour.MSDS_CMFS["CIE 1931 2 Degree Standard Observer"]
-sd_blackbody = colour.sd_blackbody(5500, cmfs.shape)
+sd_blackbody = colour.sd_blackbody(5000, cmfs.shape)
 print(sd_blackbody)
 XYZ = colour.sd_to_XYZ(sd_blackbody, cmfs)
 print(XYZ)
@@ -19,7 +19,7 @@
 
 message_box(
     "Computing the spectral radiance of a blackbody at wavelength 500nm and "
-    "temperature 5500K degrees."
+    "temperature 5000K degrees."
 )
-print(colour.colorimetry.blackbody_spectral_radiance(500 * 1e-9, 5500))
-print(colour.colorimetry.planck_law(500 * 1e-9, 5500))
+print(colour.colorimetry.blackbody_spectral_radiance(500 * 1e-9, 5000))
+print(colour.colorimetry.planck_law(500 * 1e-9, 5000))

colour/examples/temperature/examples_cct.py

@@ -53,6 +53,15 @@
 print("\n")
 
 CCT = 6503.49254150
+message_box(
+    f'Converting to "CIE UCS" colourspace "uv" chromaticity coordinates from '
+    f'given "CCT" using "Planck (1900)" method:\n\n\t{CCT_D_uv}'
+)
+print(colour.CCT_to_uv(CCT, method="Planck 1900"))
+print(colour.temperature.CCT_to_uv_Planck1900(CCT))
+
+print("\n")
+
 message_box(
     f'Converting to "CIE UCS" colourspace "uv" chromaticity coordinates from '
     f'given "CCT" using "Krystek (1985)" method:\n\n\t({CCT})'

colour/temperature/__init__.py

@@ -9,6 +9,9 @@
     Development Kit (SDK) - 1.3.0.0 -
     dng_sdk_1_3/dng_sdk/source/dng_temperature.cpp::dng_temperature::xy_coord.
     https://www.adobe.com/support/downloads/dng/dng_sdk.html
+-   :cite:`CIETC1-482004i` : CIE TC 1-48. (2004). APPENDIX E. INFORMATION ON
+    THE USE OF PLANCK'S EQUATION FOR STANDARD AIR. In CIE 015:2004 Colorimetry,
+    3rd Edition (pp. 77-82). ISBN:978-3-901906-33-6
 -   :cite:`Hernandez-Andres1999a` : Hernández-Andrés, J., Lee, R. L., &
     Romero, J. (1999). Calculating correlated color temperatures across the
     entire gamut of daylight and skylight chromaticities. Applied Optics,
@@ -58,6 +61,7 @@
 from .kang2002 import xy_to_CCT_Kang2002, CCT_to_xy_Kang2002
 from .krystek1985 import uv_to_CCT_Krystek1985, CCT_to_uv_Krystek1985
 from .mccamy1992 import xy_to_CCT_McCamy1992, CCT_to_xy_McCamy1992
+from .planck1900 import uv_to_CCT_Planck1900, CCT_to_uv_Planck1900
 from .ohno2013 import uv_to_CCT_Ohno2013, CCT_to_uv_Ohno2013
 from .robertson1968 import uv_to_CCT_Robertson1968, CCT_to_uv_Robertson1968
 
@@ -81,6 +85,10 @@
     "xy_to_CCT_McCamy1992",
     "CCT_to_xy_McCamy1992",
 ]
+__all__ += [
+    "uv_to_CCT_Planck1900",
+    "CCT_to_uv_Planck1900",
+]
 __all__ += [
     "uv_to_CCT_Ohno2013",
     "CCT_to_uv_Ohno2013",
@@ -94,6 +102,7 @@
     {
         "Krystek 1985": uv_to_CCT_Krystek1985,
         "Ohno 2013": uv_to_CCT_Ohno2013,
+        "Planck 1900": uv_to_CCT_Planck1900,
         "Robertson 1968": uv_to_CCT_Robertson1968,
     }
 )
@@ -103,8 +112,8 @@
 
 References
 ----------
-:cite:`AdobeSystems2013`, :cite:`AdobeSystems2013a`, :cite:`Krystek1985b`,
-:cite:`Ohno2014a`, :cite:`Wyszecki2000y`
+:cite:`AdobeSystems2013`, :cite:`AdobeSystems2013a`, :cite:`CIETC1-482004i`,
+:cite:`Krystek1985b`, :cite:`Ohno2014a`, :cite:`Wyszecki2000y`
 
 Aliases:
 
@@ -118,7 +127,8 @@
 def uv_to_CCT(
     uv: ArrayLike,
     method: Union[
-        Literal["Krystek 1985", "Ohno 2013", "Robertson 1968"], str
+        Literal["Krystek 1985", "Ohno 2013", "Planck 1900", "Robertson 1968"],
+        str,
     ] = "Ohno 2013",
     **kwargs: Any,
 ) -> NDArray:
@@ -137,7 +147,8 @@ def uv_to_CCT(
     Other Parameters
     ----------------
     cmfs
-        {:func:`colour.temperature.uv_to_CCT_Ohno2013`},
+        {:func:`colour.temperature.uv_to_CCT_Ohno2013`,
+        :func:`colour.temperature.uv_to_CCT_Planck1900`},
         Standard observer colour matching functions.
     count
         {:func:`colour.temperature.uv_to_CCT_Ohno2013`},
@@ -162,8 +173,9 @@ def uv_to_CCT(
 
     References
     ----------
-    :cite:`AdobeSystems2013`, :cite:`AdobeSystems2013a`, :cite:`Krystek1985b`,
-    :cite:`Ohno2014a`, :cite:`Wyszecki2000y`
+    :cite:`AdobeSystems2013`, :cite:`AdobeSystems2013a`,
+    :cite:`CIETC1-482004i`, :cite:`Krystek1985b`, :cite:`Ohno2014a`,
+    :cite:`Wyszecki2000y`
 
     Examples
     --------
@@ -184,6 +196,7 @@ def uv_to_CCT(
     {
         "Krystek 1985": CCT_to_uv_Krystek1985,
         "Ohno 2013": CCT_to_uv_Ohno2013,
+        "Planck 1900": CCT_to_uv_Planck1900,
         "Robertson 1968": CCT_to_uv_Robertson1968,
     }
 )
@@ -193,8 +206,8 @@ def uv_to_CCT(
 
 References
 ----------
-:cite:`AdobeSystems2013`, :cite:`AdobeSystems2013a`, :cite:`Krystek1985b`,
-:cite:`Ohno2014a`, :cite:`Wyszecki2000y`
+:cite:`AdobeSystems2013`, :cite:`AdobeSystems2013a`, :cite:`CIETC1-482004i`,
+:cite:`Krystek1985b`, :cite:`Ohno2014a`, :cite:`Wyszecki2000y`
 
 Aliases:
 
@@ -208,7 +221,8 @@ def uv_to_CCT(
 def CCT_to_uv(
     CCT_D_uv: ArrayLike,
     method: Union[
-        Literal["Krystek 1985", "Ohno 2013", "Robertson 1968"], str
+        Literal["Krystek 1985", "Ohno 2013", "Planck 1900", "Robertson 1968"],
+        str,
     ] = "Ohno 2013",
     **kwargs: Any,
 ) -> NDArray:
@@ -226,7 +240,8 @@ def CCT_to_uv(
     Other Parameters
     ----------------
     cmfs
-        {:func:`colour.temperature.CCT_to_uv_Ohno2013`},
+        {:func:`colour.temperature.CCT_to_uv_Ohno2013`,
+        :func:`colour.temperature.CCT_to_uv_Planck1900`},
         Standard observer colour matching functions.
 
     Returns
@@ -236,8 +251,9 @@ def CCT_to_uv(
 
     References
     ----------
-    :cite:`AdobeSystems2013`, :cite:`AdobeSystems2013a`, :cite:`Krystek1985b`,
-    :cite:`Ohno2014a`, :cite:`Wyszecki2000y`
+    :cite:`AdobeSystems2013`, :cite:`AdobeSystems2013a`,
+    :cite:`CIETC1-482004i`, :cite:`Krystek1985b`, :cite:`Ohno2014a`,
+    :cite:`Wyszecki2000y`
 
     Examples
     --------

colour/temperature/hernandez1999.py

@@ -139,13 +139,11 @@ def CCT_to_xy_Hernandez1999(
     """
 
     usage_warning(
-        '"Hernandez-Andres et al. (1999)" method for computing '
-        '"CIE xy" chromaticity coordinates from given correlated '
-        "colour temperature is not a bijective function and and"
-        "might produce unexpected results. It is given for "
-        "consistency with other correlated colour temperature "
-        "computation methods but should be avoided for practical "
-        "applications."
+        '"Hernandez-Andres et al. (1999)" method for computing "CIE xy" '
+        "chromaticity coordinates from given correlated colour temperature is "
+        "not a bijective function and might produce unexpected results. It is "
+        "given for consistency with other correlated colour temperature "
+        "computation methods but should be avoided for practical applications."
     )
 
     CCT = as_float_array(CCT)

colour/temperature/mccamy1992.py

@@ -122,12 +122,11 @@ def CCT_to_xy_McCamy1992(
     """
 
     usage_warning(
-        '"McCamy (1992)" method for computing "CIE xy" '
-        "chromaticity coordinates from given correlated colour "
-        "temperature is not a bijective function and might produce "
-        "unexpected results. It is given for consistency with other "
-        "correlated colour temperature computation methods but "
-        "should be avoided for practical applications."
+        '"McCamy (1992)" method for computing "CIE xy" chromaticity '
+        "coordinates from given correlated colour temperature is not a "
+        "bijective function and might produce unexpected results. It is given "
+        "for consistency with other correlated colour temperature computation "
+        "methods but should be avoided for practical applications."
     )
 
     CCT = as_float_array(CCT)