Interactive High-Quality Green-Screen Keying via Color Unmixing

Yagiz Aksoy, Tunc Ozan Aydin, Marc Pollefeys and Aljoscha Smolic
ACM Transactions on Graphics (TOG), 2016
Interactive High-Quality Green-Screen Keying via Color Unmixing

Major steps of our method. First, parameters of a global color model are obtained from a key frame via a simple scribble interface (a). For a different query frame (b), the global color model is refined into local color models (c) which are utilized for extracting multiple color layers via color unmixing (d). A subset of layers is then combined to get the final keying result (e). The layers can be used for compositing as well as color editing (f).

Abstract

Due to the widespread use of compositing in contemporary feature films, green-screen keying has become an essential part of post-production workflows. To comply with the ever-increasing quality requirements of the industry, specialized compositing artists spend countless hours using multiple commercial software tools, while eventually having to resort to manual painting because of the many shortcomings of these tools. Due to the sheer amount of manual labor involved in the process, new green-screen keying approaches that produce better keying results with less user interaction are welcome additions to the compositing artist's arsenal. We found that --- contrary to the common belief in the research community --- production-quality green-screen keying is still an unresolved problem with its unique challenges. In this paper, we propose a novel green-screen keying method utilizing a new energy minimization-based color unmixing algorithm. We present comprehensive comparisons with commercial software packages and relevant methods in literature, which show that the quality of our results is superior to any other currently available green-screen keying solution. Importantly, using the proposed method, these high-quality results can be generated using only one-tenth of the manual editing time that a professional compositing artist requires to process the same content having all previous state-of-the-art tools at his disposal.

Paper

Paper Video

Media Coverage

Two Minute Papers - Interactive Green-Screen Keying | Two Minute Papers #174

Gizmodo UK - Disney Algorithm Makes Green-Screen Visual Effects Even Easier

TVTechnology - Disney Research Creates Keying Algorithm, AI See 'n Say

phys.org - Green-screen keying method cuts time, boosts quality in film compositing

BibTeX

@ARTICLE{keying,
author={Ya\u{g}{\i}z Aksoy and Tun\c{c} Ozan Ayd{\i}n and Marc Pollefeys and Aljo\v{s}a Smoli\'{c}},
title={Interactive High-Quality Green-Screen Keying via Color Unmixing},
journal={ACM Trans. Graph.},
year={2016},
volume = {35},
number = {5},
pages = {152:1--152:12},
}

Data

Input sequences (780MB) Keying results (255MB)

Related Publications


Yağız Aksoy, Tunç Ozan Aydın, Aljoša Smolić and Marc Pollefeys
ACM Transactions on Graphics, 2017
We present a new method for decomposing an image into a set of soft color segments, which are analogous to color layers with alpha channels that have been commonly utilized in modern image manipulation software. We show that the resulting decomposition serves as an effective intermediate image representation, which can be utilized for performing various, seemingly unrelated image manipulation tasks. We identify a set of requirements that soft color segmentation methods have to fulfill, and present an in-depth theoretical analysis of prior work. We propose an energy formulation for producing compact layers of homogeneous colors and a color refinement procedure, as well as a method for automatically estimating a statistical color model from an image. This results in a novel framework for automatic and high-quality soft color segmentation, which is efficient, parallelizable, and scalable. We show that our technique is superior in quality compared to previous methods through quantitative analysis as well as visually through an extensive set of examples. We demonstrate that our soft color segments can easily be exported to familiar image manipulation software packages and used to produce compelling results for numerous image manipulation applications without forcing the user to learn new tools and workflows.
@ARTICLE{scs,
author={Ya\u{g}{\i}z Aksoy and Tun\c{c} Ozan Ayd{\i}n and Aljo\v{s}a Smoli\'{c} and Marc Pollefeys},
title={Unmixing-Based Soft Color Segmentation for Image Manipulation},
journal={ACM Trans. Graph.},
year={2017},
pages = {19:1-19:19},
volume = {36},
number = {2}
}

Yağız Aksoy
PhD Thesis, ETH Zurich, 2019
@phdthesis{ssi,
author={Ya\u{g}{\i}z Aksoy},
title={Soft Segmentation of Images},
year={2019},
school={ETH Zurich},
}