colour.models.rgb.transfer_functions.aces Module

Academy Color Encoding System - Log Encodings

Defines the Academy Color Encoding System (ACES) log encodings:

References

[1]The Academy of Motion Picture Arts and Sciences, Science and Technology Council, & Academy Color Encoding System (ACES) Project Subcommittee. (n.d.). Academy Color Encoding System. Retrieved February 24, 2014, from http://www.oscars.org/science-technology/council/projects/aces.html
[2]The Academy of Motion Picture Arts and Sciences, Science and Technology Council, & Academy Color Encoding System (ACES) Project Subcommittee. (2014). Technical Bulletin TB-2014-004 - Informative Notes on SMPTE ST 2065-1 – Academy Color Encoding Specification (ACES). Retrieved from https://github.com/ampas/aces-dev/tree/master/documents
[3]The Academy of Motion Picture Arts and Sciences, Science and Technology Council, & Academy Color Encoding System (ACES) Project Subcommittee. (2014). Specification S-2014-003 - ACEScc , A Logarithmic Encoding of ACES Data for use within Color Grading Systems. Retrieved from https://github.com/ampas/aces-dev/tree/master/documents
[4]The Academy of Motion Picture Arts and Sciences, Science and Technology Council, & Academy Color Encoding System (ACES) Project Subcommittee. (2014). Specification S-2013-001 - ACESproxy , an Integer Log Encoding of ACES Image Data. Retrieved from https://github.com/ampas/aces-dev/tree/master/documents
[5]The Academy of Motion Picture Arts and Sciences. (2016). Specification S-2016-001 - ACEScct, A Quasi-Logarithmic Encoding of ACES Data for use within Color Grading Systems. Retrieved October 10, 2016, from https://github.com/ampas/aces-dev/tree/v1.0.3/documents
colour.models.rgb.transfer_functions.aces.ACES_PROXY_10_CONSTANTS = {'CV_min': 64, 'steps_per_stop': 50, 'mid_CV_offset': 425, 'CV_max': 940, 'mid_log_offset': 2.5}

ACESproxy 10 bit colourspace constants.

ACES_PROXY_10_CONSTANTS : Structure

colour.models.rgb.transfer_functions.aces.ACES_PROXY_12_CONSTANTS = {'CV_min': 256, 'steps_per_stop': 200, 'mid_CV_offset': 1700, 'CV_max': 3760, 'mid_log_offset': 2.5}

ACESproxy 12 bit colourspace constants.

ACES_PROXY_12_CONSTANTS : Structure

colour.models.rgb.transfer_functions.aces.ACES_PROXY_CONSTANTS = CaseInsensitiveMapping({u'12 Bit': {'CV_min': 256, 'steps_per_stop': 200, 'mid_CV_offset': 1700, 'CV_max': 3760, 'mid_log_offset': 2.5}, u'10 Bit': {'CV_min': 64, 'steps_per_stop': 50, 'mid_CV_offset': 425, 'CV_max': 940, 'mid_log_offset': 2.5}})

Aggregated ACESproxy colourspace constants.

ACES_PROXY_CONSTANTS : CaseInsensitiveMapping
{‘10 Bit’, ‘12 Bit’}
colour.models.rgb.transfer_functions.aces.ACES_CCT_CONSTANTS = {'A': 10.5402377416545, 'B': 0.0729055341958355, 'X_BRK': 0.0078125, 'Y_BRK': 0.155251141552511}

ACEScct colourspace constants.

ACES_CCT_CONSTANTS : Structure

colour.models.rgb.transfer_functions.aces.log_encoding_ACESproxy(lin_AP1, bit_depth=u'10 Bit')[source]

Defines the ACESproxy colourspace log encoding curve / opto-electronic transfer function.

Parameters:
  • lin_AP1 (numeric or array_like) – lin_AP1 value.
  • bit_depth (unicode, optional) – {‘10 Bit’, ‘12 Bit’}, ACESproxy bit depth.
Returns:

ACESproxy non-linear value.

Return type:

numeric or ndarray

Examples

>>> log_encoding_ACESproxy(0.18)
426
colour.models.rgb.transfer_functions.aces.log_decoding_ACESproxy(ACESproxy, bit_depth=u'10 Bit')[source]

Defines the ACESproxy colourspace log decoding curve / electro-optical transfer function.

Parameters:
  • ACESproxy (numeric or array_like) – ACESproxy non-linear value.
  • bit_depth (unicode, optional) – {‘10 Bit’, ‘12 Bit’}, ACESproxy bit depth.
Returns:

lin_AP1 value.

Return type:

numeric or ndarray

Examples

>>> log_decoding_ACESproxy(426)  
0.1792444...
colour.models.rgb.transfer_functions.aces.log_encoding_ACEScc(lin_AP1)[source]

Defines the ACEScc colourspace log encoding / opto-electronic transfer function.

Parameters:lin_AP1 (numeric or array_like) – lin_AP1 value.
Returns:ACEScc non-linear value.
Return type:numeric or ndarray

Examples

>>> log_encoding_ACEScc(0.18)  
0.4135884...
colour.models.rgb.transfer_functions.aces.log_decoding_ACEScc(ACEScc)[source]

Defines the ACEScc colourspace log decoding / electro-optical transfer function.

Parameters:ACEScc (numeric or array_like) – ACEScc non-linear value.
Returns:lin_AP1 value.
Return type:numeric or ndarray

Examples

>>> log_decoding_ACEScc(0.413588402492442)  
0.1799999...
colour.models.rgb.transfer_functions.aces.log_encoding_ACEScct(lin_AP1)[source]

Defines the ACEScct colourspace log encoding / opto-electronic transfer function.

Parameters:lin_AP1 (numeric or array_like) – lin_AP1 value.
Returns:ACEScct non-linear value.
Return type:numeric or ndarray

Examples

>>> log_encoding_ACEScct(0.18)  
0.4135884...
colour.models.rgb.transfer_functions.aces.log_decoding_ACEScct(ACEScct)[source]

Defines the ACEScct colourspace log decoding / electro-optical transfer function.

Parameters:ACEScct (numeric or array_like) – ACEScct non-linear value.
Returns:lin_AP1 value.
Return type:numeric or ndarray

Examples

>>> log_decoding_ACEScct(0.413588402492442)  
0.1799999...