Add Canon CLFs

Signed-off-by: Doug Walker <[email protected]>

Author: doug-walker

opencolorio_config_aces/clf/transforms/canon/__init__.py

@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright Contributors to the OpenColorIO Project.
+
+from .generate import (
+    generate_clf_transforms_canon,
+)
+
+__all__ = [
+    "generate_clf_transforms_canon",
+]

opencolorio_config_aces/clf/transforms/canon/generate.py

@@ -0,0 +1,141 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright Contributors to the OpenColorIO Project.
+"""
+*Canon* CLF Transforms Generation
+===============================
+
+Defines procedures for generating Canon *Common LUT Format* (CLF)
+transforms:
+
+-   :func:`opencolorio_config_aces.clf.generate_clf_transforms_canon`
+"""
+
+import PyOpenColorIO as ocio
+from pathlib import Path
+
+from opencolorio_config_aces.clf.transforms import (
+    clf_basename,
+    format_clf_transform_id,
+    generate_clf_transform,
+    matrix_RGB_to_RGB_transform,
+)
+from opencolorio_config_aces.config import transform_factory
+
+__author__ = "OpenColorIO Contributors"
+__copyright__ = "Copyright Contributors to the OpenColorIO Project."
+__license__ = "New BSD License - https://opensource.org/licenses/BSD-3-Clause"
+__maintainer__ = "OpenColorIO Contributors"
+__email__ = "[email protected]"
+__status__ = "Production"
+
+__all__ = [
+    "FAMILY",
+    "GENUS",
+    "VERSION",
+    "generate_clf_transforms_canon",
+]
+
+FAMILY = "Canon"
+"""
+*CLF* transforms family.
+"""
+
+GENUS = "Input"
+"""
+*CLF* transforms genus.
+"""
+
+VERSION = "1.0"
+"""
+*CLF* transforms version.
+"""
+
+
+def generate_clf_transforms_canon(output_directory):
+    """
+    Make the CLF file for Canon C-Log3 Cinema Gamut plus matrix/curve CLFs.
+
+    Returns
+    -------
+    dict
+        Dictionary of *CLF* transforms and *OpenColorIO* `GroupTransform`
+        instances.
+
+    References
+    ----------
+    -   Canon. (2018). White Paper on Canon Log.
+        Retrieved September 22, 2022, from http://downloads.canon.com/nw/learn/\
+white-papers/cinema-eos/white-paper-canon-log-gamma-curves.pdf
+
+    Notes
+    -----
+    -   The resulting *CLF* transforms were reviewed by *Canon*.
+    """
+
+    output_directory.mkdir(parents=True, exist_ok=True)
+
+    clf_transforms = {}
+
+    bt = ocio.BuiltinTransform(style="CANON_CLOG3-CGAMUT_to_ACES2065-1")
+
+    mtx = matrix_RGB_to_RGB_transform(
+        "Cinema Gamut", "ACES2065-1", "CAT02"
+    )
+
+    aces_transform_id = (
+        "urn:ampas:aces:transformId:v1.5:"
+        "ACEScsc.Academy.CLog3_CGamut_to_ACES.a1.1.0"
+    )
+
+    # Generate full transform.
+    #     NB: This is being saved in CTF format to allow us of a Built-in Transform
+    #     and thus avoid the need for an external LUT file.
+
+    name = "CanonLog3_CinemaGamut-D55_to_ACES2065-1"
+    input_descriptor = "Canon Log 3 Cinema Gamut (Daylight)"
+    output_descriptor = "ACES2065-1"
+    clf_transform_id = format_clf_transform_id(FAMILY, GENUS, name, VERSION)
+    filename = output_directory / clf_basename(clf_transform_id)
+    clf_transforms[filename] = generate_clf_transform(
+        filename,
+        [bt],
+        clf_transform_id,
+        f"{input_descriptor} to {output_descriptor}",
+        input_descriptor,
+        output_descriptor,
+        aces_transform_id,
+    )
+
+    # Generate transform for primaries only.
+
+    name = "Linear-CinemaGamut-D55_to_ACES2065-1"
+    input_descriptor = "Linear Canon Cinema Gamut (Daylight)"
+    output_descriptor = "ACES2065-1"
+    clf_transform_id = format_clf_transform_id(FAMILY, GENUS, name, VERSION)
+    filename = output_directory / clf_basename(clf_transform_id)
+    clf_transforms[filename] = generate_clf_transform(
+        filename,
+        [mtx],
+        clf_transform_id,
+        f"{input_descriptor} to {output_descriptor}",
+        input_descriptor,
+        output_descriptor,
+    )
+
+    # Generate `NamedTransform` for log curve only.
+
+    # TODO: This will have to wait for OCIO 2.2 in order to do this without 
+    # requiring an external LUT file.
+
+    return clf_transforms
+
+
+if __name__ == "__main__":
+    import logging
+
+    logging.basicConfig()
+    logging.getLogger().setLevel(logging.INFO)
+
+    output_directory = Path(__file__).parent.resolve() / "input"
+
+    generate_clf_transforms_canon(output_directory)