colour.models.log_encoding_CanonLog3

colour.models.log_encoding_CanonLog3(x: Domain1, bit_depth: int = 10, out_normalised_code_value: bool = True, in_reflection: bool = True, method: Literal['v1', 'v1.2'] | str = 'v1.2') → Range1

Apply the Canon Log 3 log encoding opto-electronic transfer function (OETF).

Parameters:

• x (Domain1) – Linear data \(x\).

• bit_depth (int) – Bit-depth used for conversion.

• out_normalised_code_value (bool) – Whether the Canon Log 3 non-linear data is encoded as normalised code values.

• in_reflection (bool) – Whether the light level \(x\) to a camera is reflection.

• method (Literal['v1', 'v1.2'] | str) – Computation method.

Returns:

Canon Log 3 non-linear encoded data.

Return type:

numpy.ndarray

Notes

• Introspection of the grafting points by Shaw, N. (2018) shows that the Canon Log 3 v1 IDT was likely derived from its encoding curve as the latter is grafted at +/-0.014:

  >>> clog3 = 0.04076162
  >>> (clog3 - 0.073059361) / 2.3069815
  -0.014000000000000002
  >>> clog3 = 0.105357102
  >>> (clog3 - 0.073059361) / 2.3069815
  0.013999999999999997
  

Domain	Scale - Reference	Scale - 1
x	1	1

Range	Scale - Reference	Scale - 1
clog3	1	1

References

[Canon16], [Canon20]

Examples

>>> log_encoding_CanonLog3(0.18) * 100
34.3389370...