colour_clf_io.LogParams#

class colour_clf_io.LogParams(base: float | None, log_side_slope: float | None, log_side_offset: float | None, lin_side_slope: float | None, lin_side_offset: float | None, lin_side_break: float | None, linear_slope: float | None, channel: Channel | None)[source]#

Bases: XMLParsable, XMLWritable

Represent a LogParams element for a colour_clf_io.Log Process Node.

Attributes

Methods

References

Parameters:

  • base (float | None)

  • log_side_slope (float | None)

  • log_side_offset (float | None)

  • lin_side_slope (float | None)

  • lin_side_offset (float | None)

  • lin_side_break (float | None)

  • linear_slope (float | None)

  • channel (Channel | None)

base: float | None#

The base of the logarithmic function. Default is 2.

log_side_slope: float | None#

Slope” (or gain) applied to the log side of the logarithmic segment. Default is 1.

__eq__(other)#

Return self==value.

__hash__ = None#
__init__(base: float | None, log_side_slope: float | None, log_side_offset: float | None, lin_side_slope: float | None, lin_side_offset: float | None, lin_side_break: float | None, linear_slope: float | None, channel: Channel | None) → None#
Parameters:

  • base (float | None)

  • log_side_slope (float | None)

  • log_side_offset (float | None)

  • lin_side_slope (float | None)

  • lin_side_offset (float | None)

  • lin_side_break (float | None)

  • linear_slope (float | None)

  • channel (Channel | None)

Return type:

None

__repr__()#

Return repr(self).

log_side_offset: float | None#

Offset applied to the log side of the logarithmic segment. Default is 0.

lin_side_slope: float | None#

Slope of the linear side of the logarithmic segment. Default is 1.

lin_side_offset: float | None#

Offset applied to the linear side of the logarithmic segment. Default is 0.

lin_side_break: float | None#

The break-point, defined in linear space, at which the piece-wise function transitions between the logarithmic and linear segments. This is required if style=”cameraLinToLog” or “cameraLogToLin”.

linear_slope: float | None#

The slope of the linear segment of the piecewise function. This attribute does not need to be provided unless the formula being implemented requires it. The default is to calculate using linSideBreak such that the linear portion is continuous in value with the logarithmic portion of the curve, by using the value of the logarithmic portion of the curve at the break-point.

channel: Channel | None#

The colour channel to which the exponential function is applied. Possible values are “R”, “G”, “B”. If this attribute is utilized to target different adjustments per channel, then up to three LogParams elements may be used, provided that “channel” is set differently in each. However, the same value of base must be used for all channels. If this attribute is not otherwise specified, the logarithmic function is applied identically to all three colour channels.

static from_xml(xml: _Element | None, config: ParserConfig) → LogParams | None[source]#

Parse and return a colour_clf_io.LogParams class instance from the given XML element. Returns None` if the given XML element is None.

Expects the XML element to be a valid element according to the CLF specification.

Parameters:

  • xml (_Element | None) – XML element to parse.

  • config (ParserConfig) – XML parser config.

Returns:

class – Parsed XML node.

Return type:

colour_clf_io.LogParams or None

Raises:

colour_clf_io.errors.ParsingError – If the node does not conform to the specification, a ParsingError exception will be raised. The error message will indicate the details of the issue that was encountered.

to_xml() → _Element[source]#

Serialise this object as an XML object.

Return type:

lxml.etree._Element

classmethod default() → LogParams[source]#

Return the default LogParams instance. Contains the default values that should be used per specification in case the actual value is not provided.

Returns:

class – Parsed XML node.

Return type:

colour_clf_io.LogParams