/SB2383-Configuration-Generation

Eduardo Suazo and Chris Brejon experimental OpenColorIO configuration.

Primary LanguagePython

Who

If you have to ask, this probably isn't ready for you.

If you don't have to ask, the following will provide insight.

How

usage: generate_config.py [-h] [-et EXPONENT_TOE] [-ps EXPONENT_SHOULDER] [-fs FULCRUM_SLOPE] [-fi FULCRUM_INPUT] [-fo FULCRUM_OUTPUT] [-ll LIMIT_LOW] [-lh LIMIT_HIGH] [-pi PRIMARIES_INSET PRIMARIES_INSET PRIMARIES_INSET] [-pr PRIMARIES_ROTATE PRIMARIES_ROTATE PRIMARIES_ROTATE] [-to TINTING_OFFSET] [-tr TINTING_ROTATE]

All of the following creative options will influence what you end up seeing in terms of hue, value, and chroma.

-h, --help

Shows help.

-et EXPONENT_TOE, --exponent_toe EXPONENT_TOE

Set toe curve rate of change as an exponential power, hello Sean Cooper (default: 1.5)

Description

This will set the rate of change of the primary image formation curve as applied to the interstitial log encoding applied toward the lower end of the log2 encoding. Higher values tension the curve toward the y = 0.0 line, making the rate of change transition more abrupt.

Visual Impact

Will have an impact on rate of change of hue toward the lower end.

-ps EXPONENT_SHOULDER, --exponent_shoulder EXPONENT_SHOULDER

Set shoulder curve rate of change as an exponential power (default: 1.5)

Description

This will set the rate of change of the primary image formation curve as applied to the interstitial log encoding applied toward the lower end of the log2 encoding. Higher values tension the curve toward the y = 1.0 line, making the rate of change transition more abrupt.

Visual Impact

Will have an impact on rate of change of hue toward the upper end.

-fs FULCRUM_SLOPE, --fulcrum_slope FULCRUM_SLOPE

Set central section rate of change as rise over run slope (default: 2.4)

Description

This controls the slope at the fulcrum region of the curve. Higher values make the rate of change in terms of rise over run more agressive.

Visual Impact

Influences rate of change on chroma, and hue flight.

-fi FULCRUM_INPUT, --fulcrum_input FULCRUM_INPUT

Input fulcrum point relative to the normalized log2 range (default: 0.606060606061)

Description

The input value relative to the interstitial log2 encoding range. Given an achromatic sweep of values, input "middle grey".

Visual Impact

Influences value mapped to "middle grey" in relation to the output value.

-fo FULCRUM_OUTPUT, --fulcrum_output FULCRUM_OUTPUT

Output fulcrum point relative to the normalized log2 range (default: 0.4586564468643811)

Description

The output value relative to the interstitial log2 encoding range. Given an achromatic sweep of values, output "middle grey".

Visual Impact

Influences value mapped to "middle grey" in relation to the input value.

-ll LIMIT_LOW, --limit_low LIMIT_LOW

Lowest value of the normalized log2 range (default: -10.0)

Description

Given a range of open domain tristimulus values, the lowest ratio value accepted, expressed in normalized log2.

Visual Impact

In relation to the upper boundary value, determines the total ratio magnitude. Larger overall ranges increase density and may result in over-compression, and possibly posterization relative to the quantisation range of the output medium. Too large ranges may also yield an "uncanny" picture.

-lh LIMIT_HIGH, --limit_high LIMIT_HIGH

Highest value of the normalized log2 range (default: 6.5)

Description

Given a range of open domain tristimulus values, the highest ratio value accepted, expressed in normalized log2.

Visual Impact

In relation to the lower boundary value, determines the total ratio magnitude. Larger overall ranges increase density and may result in over-compression, and possibly posterization relative to the quantisation range of the output medium. Too large ranges may also yield an "uncanny" picture.

-pi PRIMARIES_INSET PRIMARIES_INSET PRIMARIES_INSET, --primaries_inset PRIMARIES_INSET PRIMARIES_INSET PRIMARIES_INSET

Percentage of scaling inset for the primaries (default: [0.15, 0.15, 0.1])

Description

Three values that dictate how much each "primary" is inset relative to the specified working space.

Visual Impact

Primarily influences the chromatic attenuation / amplification. Higher values toward one will yield more rapid attenuation of chroma, while lower values will relax, potentially to the point of posterization and picture breakup.

-pr PRIMARIES_ROTATE PRIMARIES_ROTATE PRIMARIES_ROTATE, --primaries_rotate PRIMARIES_ROTATE PRIMARIES_ROTATE PRIMARIES_ROTATE

Rotational adjustment in degrees for each of the RGB primaries, positive counterclockwise, negative clockwise (default: [1.75, -0.5, -1.0])

Description

Three values that dictate how much each "primary" is rotated in relation to the resulting working space.

Visual Impact

Primarily influences the flight of hue toward compliments, and the rate at which the hues traverse.

-to TINTING_OUTSET, --tinting_outset TINTING_OUTSET

Adjusts the tinting centroid for all R=G=B tristimulus values as a decimal percentage. (default: 0.00)

Description

The amount to shift the tint value toward the bisection line of the hull and the desired angle.

Visual Impact

Applies a general tint to the original achromatic axis flight toward white. Also impacts the rate of change and flight of all hues.

-tr TINTING_ROTATE, --tinting_rotate TINTING_ROTATE

Adjusts the rotational angle of the tinting point. Zero degrees is due north on the CIE chromaticity diagram. Positive values will rotate counterclockwise, negative values clockwise. (default: 0.0)

Description

The amount to rotate, in degrees, about the achromatic centroid toward the hull. The result shifts the achromatic centroid to the new position, applying an overall tint.

Visual Impact

Controls the general hue of the tinting centroid on its flight toward white, moving the hue to the tinting position selected in conjunction with the tinting outset value. Also impacts the rate of change and flight of all hues.