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Ambient occlusion (AO) is a widely-used real-time rendering technique which estimates light intensity on visible scene surfaces. Recently, a number of learning-based AO approaches have been proposed, which bring a new angle to solving screen space shading via a unified learning framework with competitive quality and speed. However, most such methods have high error for complex scenes or tend to ignore details. We propose an end-to-end generative adversarial network for the production of realistic AO, and explore the importance of perceptual loss in the generative model to AO accuracy. An attention mechanism is also described to improve the accuracy of details, whose effectiveness is demonstrated on a wide variety of scenes.


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AOGAN: A generative adversarial network for screen space ambient occlusion

Show Author's information Lei Ren1Ying Song1,2,3( )
Zhejiang Sci-Tech University, Hangzhou 310018, China
2011 Collaborative Innovation Center for Garment Personal Customization of Zhejiang Province, China
Key Lab of Silk and Culture Heritage and Products Design Digital Technology, Ministry of Culture and Tourism, China

Abstract

Ambient occlusion (AO) is a widely-used real-time rendering technique which estimates light intensity on visible scene surfaces. Recently, a number of learning-based AO approaches have been proposed, which bring a new angle to solving screen space shading via a unified learning framework with competitive quality and speed. However, most such methods have high error for complex scenes or tend to ignore details. We propose an end-to-end generative adversarial network for the production of realistic AO, and explore the importance of perceptual loss in the generative model to AO accuracy. An attention mechanism is also described to improve the accuracy of details, whose effectiveness is demonstrated on a wide variety of scenes.

Keywords: perceptual loss, generative adversarial network (GAN), ambient occlusion (AO), attention me-chanism

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Publication history

Received: 13 May 2021
Accepted: 13 July 2021
Published: 06 January 2022
Issue date: September 2022

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© The Author(s) 2021.

Acknowledgements

The authors would like to thank the anonymous reviewers for their helpful suggestions and comments. Ying Song was supported by the National Natural Science Foundation of China (No. 61602416), ShaoxingScience and Technology Bureau Key Project (No. 2020B41006), and the Opening Fund (No. 2020WLB10) of the Key Laboratory of Silk Culture Heritage and Product Design Digital Technology.

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