Jaakko Lehtinen

Associate Professor, Department of Computer Science, Aalto University
Distinguished Research Scientist, NVIDIA Research
ELLIS Fellow

Contact

Email: first.last at aalto.fi, jlehtinen at nvidia com
Mailing address: PO BOX 15400, FI-00076 Aalto, Finland
Office: B308, Aalto CS Building (Konemiehentie 2, Espoo, map)

Important resources

Important Note to prospective international students: unless accompanied by a strong recommendation from a faculty member I personally know, I will only be accepting new PhD students who I have not worked with before through the yearly call of the ELLIS PhD Program. If I'm not listed in the call, I will not be accepting new candidates.

Advice for (prospective) students
Important! Read this before contacting me on potential student exchanges etc.

Bill Freeman's excellent notes on how to do research
Frédo Durand's fun notes on writing
Kayvon Fatahalian's advice for CMU CS students. Applies to everyone ambitious here too.

Short Bio

I am a tenured associate professor at Aalto University, and a distinguished research scientist at NVIDIA Research. I work on computer graphics, computer vision, and machine learning, with particular interests in generative modelling, realistic image synthesis, and appearance acquisition and reproduction. Overall, I'm fascinated by the combination of machine learning techniques with physical simulators in the search for robust, interpretable AI.

Prior to taking my current positions, I spent 2007-10 as a postdoc with Frédo Durand at MIT. Before my research career, I worked for the game developer Remedy Entertainment in 1996-2005 as a graphics programmer, and contributed significantly to the graphics technology behind the worldwide blockbuster hit games Max Payne (2001), Max Payne 2 (2003), and Alan Wake (2009).

In my free time, I enjoy rock climbing, photography, cooking, and music (e.g. singing).

In the Media

New York Times interview on illusory faces generated by progressively grown GANs.
BBC Click on progressively grown GANs.
MIT Technology Review on progressively grown GANs.
The Verge on progressively grown GANs.
NVIDIA Blog on learning to restore corrupted images without ever seeing clean ones.

Suomeksi (in Finnish)

"Kuvan ihmistä ei ole olemassa", Helsingin Sanomat on progressively grown GANs.
Me on YLE Aamu-TV talking about progressively grown GANs.
Suomen Kuvalehti on GANs (paywall).
Tietoviikko on GANs.
TEK-verkkolehti on my former student, Dr. Miika Aittala, and our work on capture and reproduction of realistic surface appearance.

Practical impact

My research has had direct practical impact in at least the following ways:

The texture space shading (TSS) feature introduced in 2018 in NVIDIA's Turing GPU architecture has its direct roots in our 2011 work on decoupled sampling for graphics pipelines (with Jonathan Ragan-Kelley & al.).
Our 2010 paper on sketching clothoid splines with pleasing appearance (with Ilya Baran and Jovan Popovic) is now the basis of Adobe Illustrator's freehand drawing tool.
Our work on facial performance capture has been used extensively by Remedy Entertainment in the production of the critically-acclaimed Control (2019).
I had a small part in the design of the NVIDIA RTX ray tracing hardware architecture introduced with the Turing GPUs in 2018.

Students, collaborators, funding

PhD students

Erik Härkönen
Pauli Kemppinen
Heikki Timonen

Undergraduate RAs

Henri Ojanen, Aapo Pajunen.

Former Students

Miika Aittala (PhD 2016 → postdoc at MIT → NVIDIA Research; several thesis awards)
Markus Kettunen (PhD 2020 → postdoc at NVIDIA Research in Zurich → NVIDIA Research Helsinki)
Tuomas Kynkäänniemi (PhD 2025; Principal Machine Learning Engineer at IXI Eyewear)
Adam Celarek (Visiting MSc student → PhD at TU Wien)
Jonathan Granskog (graphics undergrad → MSc at ETH Zürich)
Peter Hedman (MSc 2015 → PhD at UCL; MSc thesis award)
Ari Silvennoinen (at Activision Central Tech; on leave from PhD)
Daniel Thul (Visiting MSc student 2015-16 → PhD at ETH Zürich)
Henrik Dahlberg (MSc 2019 → Industrial Light & Magic, London)
Dann Mensah (MSc 2023)
Sergei Kozlukov
Victoria Oberländer

Collaborators

Timo Aila, Samuli Laine, Tero Karras, Frédo Durand, Tim Weyrich, Jonathan Ragan-Kelley, Ilya Baran, Jiawen Chen, Matthias Zwicker, Marco Manzi, Fabrice Rousselle, Tzu-Mao Li, Luke Anderson.

Funding

My research is supported by the European Research Council (ERC), Academy of Finland (grant# 277833), Helsinki Doctoral Education Network in Information and Communications Technology (HICT), Aalto Media Factory, Aalto University, and NVIDIA Corporation.

Teaching

CS-C3100 Computer Graphics (Fall 2024)
CS-E5520 Advanced Computer Graphics (Spring 2024)

I had the honor to be elected Teacher of the Year 2013 in the Computer Science Degree Program at Aalto, and received the Aalto University School of Science Teaching Award in 2018. Also, both my introductory and advanced computer graphics classes have been chosen by the students to be among the Best Computer Science Classes at Aalto every year I've given them. In addition, I've helped Prof. Jukka Suomela to design and teach his multiple award-winning Programming Parallel Computers class.

Publications (Google Scholar)

2025

Evaluating and Sampling Glinty NDFs in Constant Time

Pauli Kemppinen, Loïs Paulin, Théo Thonat, Jean-Marc Thiery, Jaakko Lehtinen, and Tamy Boubekeur

ACM Trans. Graph. (Proc. SIGGRAPH Asia 2025) 44(6), 2025.

PDF

@article{Kemppinen2025GlintyNDFs,
    title="Evaluating and Sampling Glinty NDFs in Constant Time",
    author={Pauli Kemppinen and Loïs Paulin and Théo Thonat and Jean-Marc Thiery and Jaakko Lehtinen and Tamy Boubekeur},
    year=2025,
    journal={ACM Trans. Graph. (Proc. SIGGRAPH Asia 2025)},
    volume=44,
    number=6,
}

Enhanced EEG Forecasting: A Probabilistic Deep Learning Approach

Hanna Pankka, Jaakko Lehtinen, Risto J. Ilmoniemi, and Timo Roine

Neural Comput. 37(4), 2025.

DOI

@article{Pankka2025EEG,
    title="Enhanced EEG Forecasting: A Probabilistic Deep Learning Approach",
    author={Hanna Pankka and Jaakko Lehtinen and Risto J. Ilmoniemi and Timo Roine},
    year=2025,
    journal={Neural Comput.},
    volume=37,
    number=4,
}

2024

Guiding a Diffusion Model with a Bad Version of Itself

Tero Karras, Miika Aittala, Tuomas Kynkäänniemi, Jaakko Lehtinen, Timo Aila, and Samuli Laine

Neural Information Processing Systems (Proc. NeurIPS 2024) , 2024.

Note: Selected for an oral presentation (top-1% of submissions). Best paper runner-up (top-0.1% of accepted papers).

PDF

@inproceedings{Karras2024AUTO,
    title="Guiding a Diffusion Model with a Bad Version of Itself",
    author={Tero Karras and Miika Aittala and Tuomas Kynkäänniemi and Jaakko Lehtinen and Timo Aila and Samuli Laine},
    year=2024,
    booktitle={Neural Information Processing Systems (Proc. NeurIPS 2024)},
}

Applying guidance in a limited interval improves sample and distribution quality in diffusion models

Tuomas Kynkäänniemi, Miika Aittala, Tero Karras, Janne Hellsten, Samuli Laine, Timo Aila, and Jaakko Lehtinen

Neural Information Processing Systems (Proc. NeurIPS 2024) , 2024.

PDF

@inproceedings{Kynkaanniemi2024INT,
    title="Applying guidance in a limited interval improves sample and distribution quality in diffusion models",
    author={Tuomas Kynkäänniemi and Miika Aittala and Tero Karras and Janne Hellsten and Samuli Laine and Timo Aila and Jaakko Lehtinen},
    year=2024,
    booktitle={Neural Information Processing Systems (Proc. NeurIPS 2024)},
}

Analyzing and Improving the Training Dynamics of Diffusion Models

Tero Karras, Miika Aittala, Jaakko Lehtinen, Janne Hellsten, Timo Aila, and Samuli Laine

Proc. Computer Vision and Pattern Recognition (CVPR) 2024 , 2024.

Note: Selected for an oral presentation (top-1% of papers). Best paper runner-up.

PDF

@article{Karras2024EDM2,
    title="Analyzing and Improving the Training Dynamics of Diffusion Models",
    author={Tero Karras and Miika Aittala and Jaakko Lehtinen and Janne Hellsten and Timo Aila and Samuli Laine},
    year=2024,
    journal={Proc. Computer Vision and Pattern Recognition (CVPR) 2024},
}

2023

Invertible Hierarchical Generative Model for Images

Heikki Timonen, Miika Aittala, and Jaakko Lehtinen

Transactions on Machine Learning Research 11, 2023.

PDF

@article{Timonen2023Flow,
    title="Invertible Hierarchical Generative Model for Images",
    author={Heikki Timonen and Miika Aittala and Jaakko Lehtinen},
    year=2023,
    journal={Transactions on Machine Learning Research},
    volume=11,
}

A Hybrid Generator Architecture for Controllable Face Synthesis

Dann Mensah, Nam Hee Kim, Miika Aittala, Samuli Laine, and Jaakko Lehtinen

Proc. SIGGRAPH , 2023.

PDF DOI

@inproceedings{Mensah2023StyleGAN3D,
    title="A Hybrid Generator Architecture for Controllable Face Synthesis",
    author={Dann Mensah and Nam Hee Kim and Miika Aittala and Samuli Laine and Jaakko Lehtinen},
    year=2023,
    booktitle={Proc. SIGGRAPH},
}

Data-driven Pixel Filter Aware MIP Maps for SVBRDFs

Pauli Kemppinen, Miika Aittala, and Jaakko Lehtinen

Proc. Eurographics Symposium on Rendering (EGSR) , 2023.

@inproceedings{Kemppinen2023SVBRDF,
    title="Data-driven Pixel Filter Aware MIP Maps for SVBRDFs",
    author={Pauli Kemppinen and Miika Aittala and Jaakko Lehtinen},
    year=2023,
    booktitle={Proc. Eurographics Symposium on Rendering (EGSR)},
}

Solving Audio Inverse Problems with a Diffusion Model

Eloi Moliner, Jaakko Lehtinen, and Vesa Välimäki

Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP) , 2023.

Note: ICASSP Top-3% Notable Paper.

Project page Code

@inproceedings{Moliner2023Diffusion,
    title="Solving Audio Inverse Problems with a Diffusion Model",
    author={Eloi Moliner and Jaakko Lehtinen and Vesa Välimäki},
    year=2023,
    booktitle={Proc. IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP)},
}

The Role of ImageNet Classes in Fréchet Inception Distance

Tuomas Kynkäänniemi, Tero Karras, Miika Aittala, Timo Aila, and Jaakko Lehtinen

Proc. International Conference on Learning Representations (ICLR) , 2023.

Note: ICLR Top-25% Notable Paper.

Project page Code

@inproceedings{Kynkaanniemi2022FID,
    title="The Role of ImageNet Classes in Fréchet Inception Distance",
    author={Tuomas Kynkäänniemi and Tero Karras and Miika Aittala and Timo Aila and Jaakko Lehtinen},
    year=2023,
    booktitle={Proc. International Conference on Learning Representations (ICLR)},
}

2022

Generating Long Videos of Dynamic Scenes

Tim Brooks, Janne Hellsten, Miika Aittala, Ting-Chun Wang, Timo Aila, Jaakko Lehtinen, Ming-Yu Liu, Alexei Efros, and Tero Karras

Advances in Neural Information Processing Systems (Proc. NeurIPS) , 2022.

PDF

@inproceedings{Brooks2022LongVideos,
    title="Generating Long Videos of Dynamic Scenes",
    author={Tim Brooks and Janne Hellsten and Miika Aittala and Ting-Chun Wang and Timo Aila and Jaakko Lehtinen and Ming-Yu Liu and Alexei Efros and Tero Karras},
    year=2022,
    booktitle={Advances in Neural Information Processing Systems (Proc. NeurIPS)},
}

Targeted land management strategies could halve peatland fire occurrences in Central Kalimantan, Indonesia

Alexander Horton, Jaakko Lehtinen, and Matti Kummu

Nature Communications Earth & Environment , 2022.

Note: Advised ecologists Horton and Kummu on CNN models.

Project page

@article{Horton2022LandManagement,
    title="Targeted land management strategies could halve peatland fire occurrences in Central Kalimantan, Indonesia",
    author={Alexander Horton and Jaakko Lehtinen and Matti Kummu},
    year=2022,
    journal={Nature Communications Earth & Environment},
}

Disentangling Random and Cyclic Effects in Time-Lapse Sequences

Erik Härkönen, Miika Aittala, Tuomas Kynkäänniemi, Samuli Laine, Timo Aila, and Jaakko Lehtinen

ACM Trans. Graph. (Proc. SIGGRAPH) 41(4), 2022.

Code DOI

@article{Harkonen2022TLGAN,
    title="Disentangling Random and Cyclic Effects in Time-Lapse Sequences",
    author={Erik Härkönen and Miika Aittala and Tuomas Kynkäänniemi and Samuli Laine and Timo Aila and Jaakko Lehtinen},
    year=2022,
    journal={ACM Trans. Graph. (Proc. SIGGRAPH)},
    volume=41,
    number=4,
}

Simulator-Based Self-Supervision for Learned 3D Tomography Reconstruction

Onni Kosomaa, Samuli Laine, Tero Karras, Miika Aittala, and Jaakko Lehtinen

eprint arxiv: 2212.07431 , 2022.

Project page

@article{Kosomaa2022SIMCT,
    title="Simulator-Based Self-Supervision for Learned {3D} Tomography Reconstruction",
    author={Onni Kosomaa and Samuli Laine and Tero Karras and Miika Aittala and Jaakko Lehtinen},
    year=2022,
    journal={eprint arxiv: 2212.07431},
}

2021

Alias-Free Generative Adversarial Networks

Tero Karras, Miika Aittala, Samuli Laine, Erik Härkönen, Janne Hellsten, Jaakko Lehtinen, and Timo Aila

Advances in Neural Information Processing Systems (Proc. NeurIPS) , 2021.

Note: Selected for an oral presentation (top-1% of papers).

PDF

@article{Karras2021AliasFreeGAN,
    title="Alias-Free Generative Adversarial Networks",
    author={Tero Karras and Miika Aittala and Samuli Laine and Erik Härkönen and Janne Hellsten and Jaakko Lehtinen and Timo Aila},
    year=2021,
    journal={Advances in Neural Information Processing Systems (Proc. NeurIPS)},
}

Appearance-Driven Automatic 3D Model Simplification

Jon Hasselgren, Jacob Munkberg, Jaakko Lehtinen, Miika Aittala, and Samuli Laine

Proc. Eurographics Symposium on Rendering (EGSR) , 2021.

PDF

@article{Hasselgren2021ADS,
    title="Appearance-Driven Automatic 3D Model Simplification",
    author={Jon Hasselgren and Jacob Munkberg and Jaakko Lehtinen and Miika Aittala and Samuli Laine},
    year=2021,
    journal={Proc. Eurographics Symposium on Rendering (EGSR)},
}

2020

Modular Primitives for High-Performance Differentiable Rendering

Samuli Laine, Janne Hellsten, Tero Karras, Yeongho Seol, Jaakko Lehtinen, and Timo Aila

ACM Trans. Graph. (Proc. SIGGRAPH Asia) 39(6), 2020.

PDF Code DOI

@article{Laine2020DR,
    title="Modular Primitives for High-Performance Differentiable Rendering",
    author={Samuli Laine and Janne Hellsten and Tero Karras and Yeongho Seol and Jaakko Lehtinen and Timo Aila},
    year=2020,
    journal={ACM Trans. Graph. (Proc. SIGGRAPH Asia)},
    volume=39,
    number=6,
}

Training Generative Adversarial Networks with Limited Data

Tero Karras, Miika Aittala, Janne Hellsten, Samuli Laine, Jaakko Lehtinen, and Timo Aila

Advances in Neural Information Processing Systems (Proc. NeurIPS) , 2020.

Note: Selected for an oral presentation (top-1% of papers).

PDF

@article{Karras2020ADA,
    title="Training Generative Adversarial Networks with Limited Data",
    author={Tero Karras and Miika Aittala and Janne Hellsten and Samuli Laine and Jaakko Lehtinen and Timo Aila},
    year=2020,
    journal={Advances in Neural Information Processing Systems (Proc. NeurIPS)},
}

GANSpace: Discovering Interpretable GAN Controls

Erik Härkönen, Aaron Hertzmann, Jaakko Lehtinen, and Sylvain Paris

Neural Information Processing Systems (Proc. NeurIPS 2020) , 2020.

PDF Code

@article{Harkonen2020GANSpace,
    title="{GANSpace}: Discovering Interpretable {GAN} Controls",
    author={Erik Härkönen and Aaron Hertzmann and Jaakko Lehtinen and Sylvain Paris},
    year=2020,
    journal={Neural Information Processing Systems (Proc. NeurIPS 2020)},
}

Analyzing and Improving the Image Quality of StyleGAN

Tero Karras, Samuli Laine, Miika Aittala, Janne Hellsten, Jaakko Lehtinen, and Timo Aila

Proc. Computer Vision and Pattern Recognition (CVPR) 2020 , 2020.

Note: This paper describes what is known as StyleGAN2.

Project page Code

@inproceedings{Karras2020StyleGAN2,
    title="Analyzing and Improving the Image Quality of {StyleGAN}",
    author={Tero Karras and Samuli Laine and Miika Aittala and Janne Hellsten and Jaakko Lehtinen and Timo Aila},
    year=2020,
    booktitle={Proc. Computer Vision and Pattern Recognition (CVPR) 2020},
}

Predicting Mid-Air Interaction Movements and Fatigue Using Deep Reinforcement Learning

Noshaba Cheema, Laura Frey-Law, Kourosh Naderi, Jaakko Lehtinen, Philipp Slusallek, and Perttu Hämäläinen

Proc. Conference on Human Factors in Computing Systems (CHI) 2020 , 2020.

@article{Cheema2020Predicting,
    title="Predicting Mid-Air Interaction Movements and Fatigue Using Deep Reinforcement Learning",
    author={Noshaba Cheema and Laura Frey-Law and Kourosh Naderi and Jaakko Lehtinen and Philipp Slusallek and Perttu Hämäläinen},
    year=2020,
    journal={Proc. Conference on Human Factors in Computing Systems (CHI) 2020},
}

2019

Improved Precision and Recall Metric for Assessing Generative Models

Tuomas Kynkäänniemi, Tero Karras, Samuli Laine, Jaakko Lehtinen, and Timo Aila

Neural Information Processing Systems (Proc. NeurIPS) 2019 , 2019.

Project page Code

@inproceedings{Kynkaanniemi2019IPR,
    title="Improved Precision and Recall Metric for Assessing Generative Models",
    author={Tuomas Kynkäänniemi and Tero Karras and Samuli Laine and Jaakko Lehtinen and Timo Aila},
    year=2019,
    booktitle={Neural Information Processing Systems (Proc. NeurIPS) 2019},
}

High-Quality Self-Supervised Deep Image Denoising

Samuli Laine, Tero Karras, Jaakko Lehtinen, and Timo Aila

Neural Information Processing Systems (Proc. NeurIPS) 2019 , 2019.

Project page Code

@inproceedings{Laine2019Selfsup,
    title="High-Quality Self-Supervised Deep Image Denoising",
    author={Samuli Laine and Tero Karras and Jaakko Lehtinen and Timo Aila},
    year=2019,
    booktitle={Neural Information Processing Systems (Proc. NeurIPS) 2019},
}

Learning to Predict 3D Objects with an Interpolation-based Differentiable Renderer

Wenzheng Chen, Jun Gao, Huan Ling, Edward J Smith, Jaakko Lehtinen, Alec Jacobson, and Sanja Fidler

Neural Information Processing Systems (Proc. NeurIPS 2019) , 2019.

Project page

@inproceedings{chen2019dr,
    title="Learning to Predict {3D} Objects with an Interpolation-based Differentiable Renderer",
    author={Wenzheng Chen and Jun Gao and Huan Ling and Edward J Smith and Jaakko Lehtinen and Alec Jacobson and Sanja Fidler},
    year=2019,
    booktitle={Neural Information Processing Systems (Proc. NeurIPS 2019)},
}

Few-Shot Unsupervised Image-to-Image Translation

Ming-Yu Liu, Xun Huang, Arun Mallya, Tero Karras, Timo Aila, Jaakko Lehtinen, and Jan Kautz

Proc. International Conference on Computer Vision (ICCV) 2019 , 2019.

Project page

@inproceedings{Liu2019FUNIT,
    title="Few-Shot Unsupervised Image-to-Image Translation",
    author={Ming-Yu Liu and Xun Huang and Arun Mallya and Tero Karras and Timo Aila and Jaakko Lehtinen and Jan Kautz},
    year=2019,
    booktitle={Proc. International Conference on Computer Vision (ICCV) 2019},
}

E-LPIPS: Robust Perceptual Image Similarity via Random Transformation Ensembles

Markus Kettunen, Erik Härkönen, and Jaakko Lehtinen

eprint arxiv: 1906.03973 , 2019.

Project page Code

@article{Kettunen2019ELPIPS,
    title="{E-LPIPS}: Robust Perceptual Image Similarity via Random Transformation Ensembles",
    author={Markus Kettunen and Erik Härkönen and Jaakko Lehtinen},
    year=2019,
    journal={eprint arxiv: 1906.03973},
}

Sample-Based Monte Carlo Denoising Using a Kernel-Splatting Network

Michaël Gharbi, Tzu-Mao Li, Miika Aittala, Jaakko Lehtinen, and Frédo Durand

ACM Trans. Graph. (Proc. SIGGRAPH) 38(4), 2019.

Project page PDF

@article{Gharbi2019SIG,
    title="Sample-Based {Monte} {Carlo} Denoising Using a Kernel-Splatting Network",
    author={Michaël Gharbi and Tzu-Mao Li and Miika Aittala and Jaakko Lehtinen and Frédo Durand},
    year=2019,
    journal={ACM Trans. Graph. (Proc. SIGGRAPH)},
    volume=38,
    number=4,
}

Deep Convolutional Reconstruction for Gradient-Domain Rendering

Markus Kettunen, Erik Härkönen, and Jaakko Lehtinen

ACM Trans. Graph. (Proc. SIGGRAPH) 38(4), 2019.

Note: Open Access PDF available from ACM through link below

Project page

@article{Kettunen2019SIG,
    title="Deep Convolutional Reconstruction for Gradient-Domain Rendering",
    author={Markus Kettunen and Erik Härkönen and Jaakko Lehtinen},
    year=2019,
    journal={ACM Trans. Graph. (Proc. SIGGRAPH)},
    volume=38,
    number=4,
}

Quantifying the Error of Light Transport Algorithms

Adam Celarek, Wenzel Jakob, Michael Wimmer, and Jaakko Lehtinen

Computer Graphics Forum (Proc. EGSR 2019) 38(4), 2019.

Project page Code

@article{Celarek2019EGSR,
    title="Quantifying the Error of Light Transport Algorithms",
    author={Adam Celarek and Wenzel Jakob and Michael Wimmer and Jaakko Lehtinen},
    year=2019,
    journal={Computer Graphics Forum (Proc. EGSR 2019)},
    volume=38,
    number=4,
}

2018

Differentiable Monte Carlo Ray Tracing through Edge Sampling

Tzu-Mao Li, Miika Aittala, Frédo Durand, and Jaakko Lehtinen

ACM Trans. Graph. (Proc. SIGGRAPH Asia) 37(6), 2018.

Project page

@article{Li2018SIGA,
    title="Differentiable Monte Carlo Ray Tracing through Edge Sampling",
    author={Tzu-Mao Li and Miika Aittala and Frédo Durand and Jaakko Lehtinen},
    year=2018,
    journal={ACM Trans. Graph. (Proc. SIGGRAPH Asia)},
    volume=37,
    number=6,
}

Noise2Noise: Learning Image Restoration without Clean Data

Jaakko Lehtinen, Jacob Munkberg, Jon Hasselgren, Samuli Laine, Tero Karras, Miika Aittala, and Timo Aila

Proc. International Conference on Machine Learning (ICML) 80, 2018.

Project page PDF Video

@inproceedings{Lehtinen2018ICML,
    title="Noise2Noise: Learning Image Restoration without Clean Data",
    author={Jaakko Lehtinen and Jacob Munkberg and Jon Hasselgren and Samuli Laine and Tero Karras and Miika Aittala and Timo Aila},
    year=2018,
    booktitle={Proceedings of the 35th International Conference on Machine Learning, PMLR},
    volume=80,
}

Progressive Growing of GANs for Improved Quality, Stability, and Variation

Tero Karras, Timo Aila, Samuli Laine, and Jaakko Lehtinen

Proc. International Conference on Learning Representations (ICLR) , 2018.

Note: Selected for an oral presentation. See the Media section above for a sample of the news coverage and buzz.

Project page PDF Video

@inproceedings{Karras2018ICLR,
    title="Progressive Growing of {GANs} for Improved Quality, Stability, and Variation",
    author={Tero Karras and Timo Aila and Samuli Laine and Jaakko Lehtinen},
    year=2018,
    booktitle={Proc. International Conference on Learning Representations (ICLR)},
}

2017

Real-time Global Illumination by Precomputed Local Reconstruction from Sparse Radiance Probes

Ari Silvennoinen and Jaakko Lehtinen

ACM Transactions on Graphics (Proc. SIGGRAPH Asia) 36(6), 2017.

DOI (Open Access)

@article{Silvennoinen2017SIGA,
    title="Real-time Global Illumination by Precomputed Local Reconstruction from Sparse Radiance Probes",
    author={Ari Silvennoinen and Jaakko Lehtinen},
    year=2017,
    journal={ACM Trans. Graph.},
    volume=36,
    number=6,
}

Audio-Driven Facial Animation by Joint End-to-End Learning of Pose and Emotion

Tero Karras, Timo Aila, Samuli Laine, Antti Herva, and Jaakko Lehtinen

ACM Transactions on Graphics (Proc. SIGGRAPH) 36(4), 2017.

PDF Video

@article{Karras2017SIG,
    title="Audio-Driven Facial Animation by Joint End-to-End Learning of Pose and Emotion",
    author={Tero Karras and Timo Aila and Samuli Laine and Antti Herva and Jaakko Lehtinen},
    year=2017,
    journal={ACM Trans. Graph.},
    volume=36,
    number=4,
}

Aether: An Embedded Domain Specific Sampling Language for Monte Carlo Rendering

Luke Anderson, Tzu-Mao Li, Jaakko Lehtinen, and Frédo Durand

ACM Transactions on Graphics (Proc. SIGGRAPH) 36(4), 2017.

Project page

@article{Anderson2017SIG,
    title="Aether: An Embedded Domain Specific Sampling Language for Monte Carlo Rendering",
    author={Luke Anderson and Tzu-Mao Li and Jaakko Lehtinen and Frédo Durand},
    year=2017,
    journal={ACM Trans. Graph.},
    volume=36,
    number=4,
}

Production-Level Facial Performance Capture Using Deep Convolutional Neural Networks

Samuli Laine, Tero Karras, Timo Aila, Antti Herva, Shunsuke Saito, Ronald Yu, Hao Li, and Jaakko Lehtinen

Proc. SIGGRAPH/EUROGRAPHICS Symposium on Computer Animation (SCA) 2017 , 2017.

PDF Video

@inproceedings{Karras2017SCA,
    title="Production-Level Facial Performance Capture Using Deep Convolutional Neural Networks",
    author={Samuli Laine and Tero Karras and Timo Aila and Antti Herva and Shunsuke Saito and Ronald Yu and Hao Li and Jaakko Lehtinen},
    year=2017,
    booktitle={Proc. SIGGRAPH/EUROGRAPHICS Symposium on Computer Animation (SCA) 2017},
}

Sequential Monte Carlo Instant Radiosity

Peter Hedman, Tero Karras, and Jaakko Lehtinen

IEEE Transactions on Visualization and Computer Graphics 23(5), 2017.

Note: This is an extended version of the I3D 2016 paper of the same name (see below).

Project page DOI

@article{Hedman2017TVCG,
    title="Sequential {Monte} {Carlo} Instant Radiosity",
    author={Peter Hedman and Tero Karras and Jaakko Lehtinen},
    year=2017,
    journal={IEEE Transactions on Visualization and Computer Graphics},
    volume=23,
    number=5,
}

2016

Temporal Gradient-Domain Path Tracing

Marco Manzi, Markus Kettunen, Matthias Zwicker, Frédo Durand, and Jaakko Lehtinen

ACM Transactions on Graphics (Proc. SIGGRAPH Asia) 35(6), 2016.

Project page Code DOI (Open Access)

@article{Manzi2016SIGA,
    title="Temporal Gradient-Domain Path Tracing",
    author={Marco Manzi and Markus Kettunen and Matthias Zwicker and Frédo Durand and Jaakko Lehtinen},
    year=2016,
    journal={ACM Trans. Graph.},
    volume=35,
    number=6,
}

Reflectance Modeling by Neural Texture Synthesis

Miika Aittala, Timo Aila, and Jaakko Lehtinen

ACM Transactions on Graphics (Proc. SIGGRAPH) 35(4), 2016.

Project page DOI (Open Access)

@article{Aittala2016SIG,
    title="Reflectance Modeling by Neural Texture Synthesis",
    author={Miika Aittala and Timo Aila and Jaakko Lehtinen},
    year=2016,
    journal={ACM Trans. Graph.},
    volume=35,
    number=4,
}

Sequential Monte Carlo Instant Radiosity

Peter Hedman, Tero Karras, and Jaakko Lehtinen

Proc. ACM SIGGRAPH Symposium on Interactive 3D Graphics and Games 2016 , 2016.

Project page DOI

@inproceedings{Hedman2016I3D,
    title="Sequential {Monte Carlo} Instant Radiosity",
    author={Peter Hedman and Tero Karras and Jaakko Lehtinen},
    year=2016,
    booktitle={Proc. ACM SIGGRAPH Symposium on Interactive 3D Graphics and Games 2016},
}

2015

Anisotropic Gaussian Mutations for Metropolis Light Transport through Hessian-Hamiltonian Dynamics

Tzu-Mao Li, Jaakko Lehtinen, Ravi Ramamoorthi, Wenzel Jakob, and Frédo Durand

ACM Transactions on Graphics (Proc. SIGGRAPH Asia) 34(6), 2015.

Project page DOI

@article{Li2015SIGA,
    title="Anisotropic Gaussian Mutations for {Metropolis} Light Transport through {Hessian-Hamiltonian} Dynamics",
    author={Tzu-Mao Li and Jaakko Lehtinen and Ravi Ramamoorthi and Wenzel Jakob and Frédo Durand},
    year=2015,
    journal={ACM Trans. Graph.},
    volume=34,
    number=6,
}

Gradient-Domain Bidirectional Path Tracing

Marco Manzi, Markus Kettunen, Miika Aittala, Jaakko Lehtinen, Frédo Durand, and Matthias Zwicker

Proc. Eurographics Symposium on Rendering 2015 (Experimental Ideas & Implementations) , 2015.

Project page Code

@inproceedings{Manzi2015EGSR,
    title="Gradient-Domain Bidirectional Path Tracing",
    author={Marco Manzi and Markus Kettunen and Miika Aittala and Jaakko Lehtinen and Frédo Durand and Matthias Zwicker},
    year=2015,
    booktitle={Proc. Eurographics Symposium on Rendering 2015 (Experimental Ideas & Implementations)},
}

Gradient-Domain Path Tracing

Markus Kettunen, Marco Manzi, Miika Aittala, Jaakko Lehtinen, Frédo Durand, and Matthias Zwicker

ACM Transactions on Graphics (Proc. SIGGRAPH) 34(4), 2015.

Project page Code DOI (Open Access)

@article{Kettunen2015SIG,
    title="Gradient-Domain Path Tracing",
    author={Markus Kettunen and Marco Manzi and Miika Aittala and Jaakko Lehtinen and Frédo Durand and Matthias Zwicker},
    year=2015,
    journal={ACM Trans. Graph.},
    volume=34,
    number=4,
}

Two-shot SVBRDF Capture for Stationary Materials

Miika Aittala, Tim Weyrich, and Jaakko Lehtinen

ACM Transactions on Graphics (Proc. SIGGRAPH) 34(4), 2015.

Project page DOI (Open Access)

@article{Aittala2015SIG,
    title="Two-shot {SVBRDF} Capture for Stationary Materials",
    author={Miika Aittala and Tim Weyrich and Jaakko Lehtinen},
    year=2015,
    journal={ACM Trans. Graph.},
    volume=34,
    number=4,
}

Recent advances in adaptive sampling and reconstruction for Monte Carlo rendering

Matthias Zwicker, Wojciech Jarosz, Jaakko Lehtinen, Bochang Moon, Ravi Ramamoorthi, Fabrice Rousselle, Pradeep Sen, Cyril Soler, and Sung-Eui Yoon

Computer Graphics Forum (STAR State of the Art Report) 34(2), 2015.

Project page DOI

@article{Zwicker2015STAR,
    title="Recent advances in adaptive sampling and reconstruction for {Monte} {Carlo} rendering",
    author={Matthias Zwicker and Wojciech Jarosz and Jaakko Lehtinen and Bochang Moon and Ravi Ramamoorthi and Fabrice Rousselle and Pradeep Sen and Cyril Soler and Sung-Eui Yoon},
    year=2015,
    journal={Computer Graphics Forum},
    volume=34,
    number=2,
}

2014

Improved Sampling for Gradient-Domain Metropolis Light Transport

Marco Manzi, Fabrice Rousselle, Markus Kettunen, Jaakko Lehtinen, and Matthias Zwicker

ACM Transactions on Graphics (Proc. SIGGRAPH Asia) 33(6), 2014.

Project page DOI (Open Access)

@article{Manzi2014SIGA,
    title="Improved Sampling for Gradient-Domain {Metropolis} Light Transport",
    author={Marco Manzi and Fabrice Rousselle and Markus Kettunen and Jaakko Lehtinen and Matthias Zwicker},
    year=2014,
    journal={ACM Trans. Graph.},
    volume=33,
    number=6,
}

Online Motion Synthesis Using Sequential Monte Carlo

Perttu Hämäläinen, Sebastian Eriksson, Esa Tanskanen, Ville Kyrki, and Jaakko Lehtinen

ACM Transactions on Graphics (Proc. SIGGRAPH) 33(4), 2014.

Project page DOI

@article{Hamalainen2014SIG,
    title="Online Motion Synthesis Using Sequential {Monte} {Carlo}",
    author={Perttu Hämäläinen and Sebastian Eriksson and Esa Tanskanen and Ville Kyrki and Jaakko Lehtinen},
    year=2014,
    journal={ACM Trans. Graph.},
    volume=33,
    number=4,
}

Occluder Simplification Using Planar Sections

Ari Silvennoinen, Hannu Saransaari, Samuli Laine, and Jaakko Lehtinen

Computer Graphics Forum 33(1), 2014.

DOI

@article{Silvennoinen2014CGF,
    title="Occluder Simplification Using Planar Sections",
    author={Ari Silvennoinen and Hannu Saransaari and Samuli Laine and Jaakko Lehtinen},
    year=2014,
    journal={Computer Graphics Forum},
    volume=33,
    number=1,
}

2013

Gradient-Domain Metropolis Light Transport

Jaakko Lehtinen, Tero Karras, Samuli Laine, Miika Aittala, Frédo Durand, and Timo Aila

ACM Transactions on Graphics (Proc. SIGGRAPH) 32(4), 2013.

Project page DOI

@article{Lehtinen2013SIG,
    title="Gradient-Domain {Metropolis} Light Transport",
    author={Jaakko Lehtinen and Tero Karras and Samuli Laine and Miika Aittala and Frédo Durand and Timo Aila},
    year=2013,
    journal={ACM Trans. Graph.},
    volume=32,
    number=4,
}

Practical SVBRDF Capture in the Frequency Domain

Miika Aittala, Tim Weyrich, and Jaakko Lehtinen

ACM Transactions on Graphics (Proc. SIGGRAPH) 32(4), 2013.

Project page DOI

@article{Aittala2013SIG,
    title="Practical {SVBRDF} Capture in the Frequency Domain",
    author={Miika Aittala and Tim Weyrich and Jaakko Lehtinen},
    year=2013,
    journal={ACM Trans. Graph.},
    volume=32,
    number=4,
}

2012

Reconstructing the Indirect Light Field for Global Illumination

Jaakko Lehtinen, Timo Aila, Samuli Laine, and Frédo Durand

ACM Transactions on Graphics (Proc. SIGGRAPH) 31(4), 2012.

Project page

@article{Lehtinen2012SIG,
    title="Reconstructing the Indirect Light Field for Global Illumination",
    author={Jaakko Lehtinen and Timo Aila and Samuli Laine and Frédo Durand},
    year=2012,
    journal={ACM Trans. Graph.},
    volume=31,
    number=4,
}

2011

Temporal Light Field Reconstruction for Rendering Distribution Effects

Jaakko Lehtinen, Timo Aila, Jiawen Chen, Samuli Laine, and Frédo Durand

ACM Transactions on Graphics (Proc. SIGGRAPH) 30(4), 2011.

Project page

@article{Lehtinen2011SIG,
    title="Temporal Light Field Reconstruction for Rendering Distribution Effects",
    author={Jaakko Lehtinen and Timo Aila and Jiawen Chen and Samuli Laine and Frédo Durand},
    year=2011,
    journal={ACM Trans. Graph.},
    volume=30,
    number=4,
}

Clipless Dual-Space Bounds for Faster Stochastic Rasterization

Samuli Laine, Timo Aila, Tero Karras, and Jaakko Lehtinen

ACM Transactions on Graphics (Proc. SIGGRAPH) 30(4), 2011.

PDF DOI

@article{Laine2011SIG,
    title="Clipless Dual-Space Bounds for Faster Stochastic Rasterization",
    author={Samuli Laine and Timo Aila and Tero Karras and Jaakko Lehtinen},
    year=2011,
    journal={ACM Trans. Graph.},
    volume=30,
    number=4,
}

Decoupled Sampling for Real-Time Graphics Pipelines

Jonathan Ragan-Kelley, Jaakko Lehtinen, Jiawen Chen, Michael Doggett, and Frédo Durand

ACM Transactions on Graphics 30(3), 2011.

Note: Presented at SIGGRAPH 2011.

Project page

@article{JRK2011TOG,
    title="Decoupled Sampling for Real-Time Graphics Pipelines",
    author={Jonathan Ragan-Kelley and Jaakko Lehtinen and Jiawen Chen and Michael Doggett and Frédo Durand},
    year=2011,
    journal={ACM Trans. Graph.},
    volume=30,
    number=3,
}

2010

A Hierarchical Volumetric Shadow Algorithm for Single Scattering

Ilya Baran, Jiawen Chen, Jonathan Ragan-Kelley, Frédo Durand, and Jaakko Lehtinen

ACM Transactions on Graphics (Proc. SIGGRAPH Asia) 29(6), 2010.

Project page

@article{Baran2010SIGA,
    title="A Hierarchical Volumetric Shadow Algorithm for Single Scattering",
    author={Ilya Baran and Jiawen Chen and Jonathan Ragan-Kelley and Frédo Durand and Jaakko Lehtinen},
    year=2010,
    journal={ACM Trans. Graph.},
    volume=29,
    number=6,
}

Sketching Clothoid Splines Using Shortest Paths

Ilya Baran, Jaakko Lehtinen, and Jovan Popović

Computer Graphics Forum (Proc. Eurographics 2010) 29(2), 2010.

Project page

@article{Baran2010EG,
    title="Sketching Clothoid Splines Using Shortest Paths",
    author={Ilya Baran and Jaakko Lehtinen and Jovan Popović},
    year=2010,
    journal={Computer Graphics Forum},
    volume=29,
    number=2,
}

2008

A Meshless Hierarchical Representation for Light Transport

Jaakko Lehtinen, Matthias Zwicker, Emmanuel Turquin, Janne Kontkanen, Frédo Durand, François Sillion, and Timo Aila

ACM Transactions on Graphics (Proc. SIGGRAPH) 27(3), 2008.

Project page

@article{Lehtinen2008SIG,
    title="A Meshless Hierarchical Representation for Light Transport",
    author={Jaakko Lehtinen and Matthias Zwicker and Emmanuel Turquin and Janne Kontkanen and Frédo Durand and François Sillion and Timo Aila},
    year=2008,
    journal={ACM Trans. Graph.},
    volume=27,
    number=3,
}

2007

Incremental Instant Radiosity for Real-Time Indirect Illumination

Samuli Laine, Hannu Saransaari, Janne Kontkanen, Jaakko Lehtinen, and Timo Aila

Rendering Techniques 2007 (Proc. Eurographics Symposium on Rendering) , 2007.

PDF

@inproceedings{Laine2007EGSR,
    title="Incremental Instant Radiosity for Real-Time Indirect Illumination",
    author={Samuli Laine and Hannu Saransaari and Janne Kontkanen and Jaakko Lehtinen and Timo Aila},
    year=2007,
    booktitle={Rendering Techniques 2007 (Proc. Eurographics Symposium on Rendering)},
}

A Framework for Precomputed and Captured Light Transport

Jaakko Lehtinen

ACM Transactions on Graphics 26(4), 2007.

Note: Presented at SIGGRAPH 2008.

DOI

@article{Lehtinen2007TOG,
    title="A Framework for Precomputed and Captured Light Transport",
    author={Jaakko Lehtinen},
    year=2007,
    journal={ACM Trans. Graph.},
    volume=26,
    number=4,
}

2006

An Improved Physically-Based Soft Shadow Volume Algorithm

Jaakko Lehtinen, Samuli Laine, and Timo Aila

Computer Graphics Forum (Proc. Eurographics 2006) 25(3), 2006.

PDF

@article{Lehtinen2006EG,
    title="An Improved Physically-Based Soft Shadow Volume Algorithm",
    author={Jaakko Lehtinen and Samuli Laine and Timo Aila},
    year=2006,
    journal={Computer Graphics Forum},
    volume=25,
    number=3,
}

2005

Soft Shadow Volumes for Ray Tracing

Samuli Laine, Timo Aila, Ulf Assarsson, Jaakko Lehtinen, and Tomas Akenine-Möller

ACM Transactions on Graphics (Proc. SIGGRAPH) 24(3), 2005.

Note: See our EG 2006 paper for improvements.

PDF DOI

@article{Laine2005SIG,
    title="Soft Shadow Volumes for Ray Tracing",
    author={Samuli Laine and Timo Aila and Ulf Assarsson and Jaakko Lehtinen and Tomas Akenine-Möller},
    year=2005,
    journal={ACM Trans. Graph.},
    volume=24,
    number=3,
}

2004

Hemispherical Rasterization for Self-Shadowing of Dynamic Objects

Jan Kautz, Jaakko Lehtinen, and Timo Aila

Rendering Techniques 2004 (Proc. Eurographics Symposium on Rendering) , 2004.

PDF

@inproceedings{Kautz2004EGSR,
    title="Hemispherical Rasterization for Self-Shadowing of Dynamic Objects",
    author={Jan Kautz and Jaakko Lehtinen and Timo Aila},
    year=2004,
    booktitle={Rendering Techniques 2004 (Proc. Eurographics Symposium on Rendering)},
}

2003

Matrix Radiance Transfer

Jaakko Lehtinen and Jan Kautz

Proc. ACM SIGGRAPH 2003 Symposium on Interactive 3D Graphics , 2003.

PDF

@inproceedings{Lehtinen2003I3D,
    title="Matrix Radiance Transfer",
    author={Jaakko Lehtinen and Jan Kautz},
    year=2003,
    booktitle={Proc. ACM SIGGRAPH 2003 Symposium on Interactive 3D Graphics},
}

Theses

Theory and Algorithms for Efficient Physically-Based Illumination

Jaakko Lehtinen

Doctoral dissertation. Publications in Telecommunications Software and Multimedia TML-A20, Helsinki University of Technology, 2007.

DOI

@phdthesis{Lehtinen2007PHD,
    title="Theory and Algorithms for Efficient Physically-Based Illumination",
    author={Jaakko Lehtinen},
    year=2007,
    school={Publications in Telecommunications Software and Multimedia TML-A20, Helsinki University of Technology},
}

Foundations of Precomputed Radiance Transfer

Jaakko Lehtinen

Master's thesis, Helsinki University of Technology, 2004.

Note: An extended version of this thesis appears in my 2007 paper 'A framework for precomputed and captured light transport'.

PDF

@phdthesis{Lehtinen2004MSC,
    title="Foundations of Precomputed Radiance Transfer",
    author={Jaakko Lehtinen},
    year=2004,
    school={Helsinki University of Technology},
    type={Master's thesis},

}