EddyGun/aces-dev

Academy Color Encoding System Developer Resources

The Academy Color Encoding System (ACES) is a set of components that facilitates a wide range of motion picture and television workflows while eliminating the ambiguity of legacy file formats. The system is designed to support both all-digital and hybrid film-digital motion picture workflows.

The basic ACES components are:

Color encoding and metric specifications, file format specifications, color transformations, and an open source reference implementation
A set of reference images and calibration targets for film scanners and recorders
Documentation on the system and software tools

This toolkit is intended to serve as a distribution mechanism for key components of the system, including the reference implementation transforms, reference images, and documentation.

Package Contents

documents/ – ACES-related documents
images/ - "golden" images created using the reference implementation transforms
transforms/ - ACES reference implementation transforms

Changes from Previous Release

Though the "master" branch is 1.0.3, the current major version of ACES remains 1.0. The 1.0.3 "patch" release adds features, but does not change the look, or modify the existing core transforms beyond addressing reported bugs since the major version release.

As always, you should check the hotfixes and dev branches for the latest bug fixes and new features that will ultimately be rolled into a future version of ACES. These improvements will continue to be staged on the dev branch for testing as they become available.

Included in ACES 1.0.3:

New Features:
- Add new ACEScct color correction working space transforms
- Add ACEScct specification document
- Add Sony S-Log3 / S-Gamut3 IDTs
- Add functions to convert between premultiplied and straight alpha
- Add D65 RGB Monitor ODT
- Add new reference images for new transforms
Bug Fixes:
- Update copy and paste typo in ACESproxy document
- Update ODT functions legal range input variable usage to avoid a situation where it may not execute as intended.
- Update miscellaneous to local variables in utility functions to avoid clashes with existing global variables
- Update miscellaneous minor errors in Transform IDs
- Update miscellaneous transforms missing ACESuserName Tags
Other:
- Update IDT READMEs to reflect latest manufacturer provided information including broken links
- Restructure utility and lib functions directories for use clarification
- Restructure directories to consolidate CSC transforms
- Update equation variables names in ACEScc and ACESproxy documents for greater clarity
- Miscellaneous math simplifications in utility functions
- Miscellaneous white space fixes in CTL transforms
- Miscellaneous typo fixes in CTL transform comments
- Remove version number from CTL file names
- Add Python script to rename CTL files based on TransformID
- Update all documents to remove version numbers and use date as unique identifier
- Update all documents to use vector logo
- Update reference images to reflect code changes
- Update README and CHANGELOG

For a more detailed list of changes see the CHANGELOG and in the commit history.

Notes on ACEScct

A new color correction working space has been added to ACES 1.0.3. The new working space, known as ACEScct, is intended to address some colorists' desire for a grading behavior similar to that of traditional log film scans. ACEScct is intended to be an alternate color correction working space to ACEScc for those who prefer its grading behavior. As such, developers implementing ACES 1.0.3 in products that previously only used ACEScc should offer end users a choice of ACEScc or ACEScct in the user interface as the color correction working space. Among the characteristics of ACEScct is a more distict "milking" or "fogging" of shadows when a lift operation is applied when compared to the same operation applied in ACEScc. This is a result of the addition of a "toe" to the non-linear encoding function. It is important to note that ACEScct is NOT compatible with ASC-CDL values generated on-set using the ACESproxy encoding. If there is a need to reproduce a look generated on-set where ACESproxy was used, ACEScc must be used in the dailies and/or DI environment.

Versioning

The links to the current and all past versions of the ACES Developer Resources can be found at https://github.com/ampas/aces-dev/releases.

Source code is version controlled using the git version control system and hosted on GitHub at https://github.com/ampas/aces-dev/.

Individual files now conform to the ACES System Versioning Specification. Details can be found in the Academy Specification "S-2014-002 - Academy Color Encoding System - Versioning System" included in documents/

Branch Structure

Master Branch

The current release version of ACES can always be found at the HEAD of the master branch. The master branch contains no intermediate commits and all commits on the master branch are tagged to represent a release of ACES.

Dev Branch

Intermediate commits between releases will be staged on the dev branch. Commits staged on the dev branch, but not yet merged into the master, should be considered as "planned for inclusion" in the next release version. Commits on the dev branch will ultimately be merged into the master branch as part of a future release.

Hotfixes Branch

In some instances it may be necessary to create a hotfixes branch. The hotfixes branch will include important, but not fully tested, fixes for bugs found in a particular release. Hotfixes should only be implemented by developers if the bug they are intending to correct is encountered in the course of production and is deemed to be a barrier to using a particular ACES release. Hotfixes, once fully tested, will be merged into the dev branch, and ultimately the master.

Prerequisites

Color Transformation Language

Color Transformation Language (CTL) can be downloaded from https://github.com/ampas/CTL

License Terms for Academy Color Encoding System Components

Academy Color Encoding System (ACES) software and tools are provided by the Academy under the following terms and conditions: A worldwide, royalty-free, non-exclusive right to copy, modify, create derivatives, and use, in source and binary forms, is hereby granted, subject to acceptance of this license.

Performance of any of the aforementioned acts indicates acceptance to be bound by the following terms and conditions:

Copies of source code, in whole or in part, must retain the above copyright notice, this list of conditions and the Disclaimer of Warranty.
Use in binary form must retain the above copyright notice, this list of conditions and the Disclaimer of Warranty in the documentation and/or other materials provided with the distribution.
Nothing in this license shall be deemed to grant any rights to trademarks, copyrights, patents, trade secrets or any other intellectual property of A.M.P.A.S. or any contributors, except as expressly stated herein.
Neither the name "A.M.P.A.S." nor the name of any other contributors to this software may be used to endorse or promote products derivative of or based on this software without express prior written permission of A.M.P.A.S. or the contributors, as appropriate.

This license shall be construed pursuant to the laws of the State of California, and any disputes related thereto shall be subject to the jurisdiction of the courts therein.

Disclaimer of Warranty: THIS SOFTWARE IS PROVIDED BY A.M.P.A.S. AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT ARE DISCLAIMED. IN NO EVENT SHALL A.M.P.A.S., OR ANY CONTRIBUTORS OR DISTRIBUTORS, BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, RESITUTIONARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

WITHOUT LIMITING THE GENERALITY OF THE FOREGOING, THE ACADEMY SPECIFICALLY DISCLAIMS ANY REPRESENTATIONS OR WARRANTIES WHATSOEVER RELATED TO PATENT OR OTHER INTELLECTUAL PROPERTY RIGHTS IN THE ACADEMY COLOR ENCODING SYSTEM, OR APPLICATIONS THEREOF, HELD BY PARTIES OTHER THAN A.M.P.A.S.,WHETHER DISCLOSED OR UNDISCLOSED.

EddyGun / aces-dev