2023

HyperPRI: A Dataset of Hyperspectral Images for Underground Plant Root Study
Yangyang Song, Gerard Sapes, Spencer Jordan Chang, Retish Chowdhry, Tomas Mejia, Anna Hampton, Shelby Kucharski, TM Shahriar Sazzad, Yuxuan Zhang, S. J. Koppal, Alina Zare, Stefan Gerber, Chris H Wilson, William Hammond
CVPPA ICCV 2023
PDF | PROJECT PAGE

Schrödinger’s Camera: First Steps Towards a Quantum-Based Privacy Preserving Camera
Hannah Kirkland, S. J. Koppal
arXiv 2023 | TCV CVPRW 2023 | WiCV CVPRW 2023 (extended abstract)
PDF | CODE | PROJECT PAGE

Energy-Efficient Adaptive 3D Sensing
Brevin Tilmon, Zhanghao Sun, S. J. Koppal, Yicheng Wu, Georgios Evangelidis, Ramzi Zahreddine, Guru Krishnan, Sizhuo Ma, Jian Wang
CVPR 2023
PDF | PROJECT PAGE

Give me some room please! Personal space bubbles for safety and performance
Karina LaRubbio, Ethan Wilson, S. J. Koppal, Sophie Jörg , Eakta Jain
IEEE VR Conference 2023 (Poster)
PDF

Event-based Dual Photography for Transparent Scene Reconstruction
Xiaomeng Liu, Joshua D. Rego, Suren Jayasuriya, S. J. Koppal
Optics Letters 2023
PDF

2022

BlockSLAM: Privacy and Security in Spatial Computing for the Gig Economy
S. J. Koppal
FOCUS Lab Position Paper 2022
PDF

Optical MEMS enable next generation solutions for robot vision and human-robot interaction
Daniel Lovell, Veljko Milanovic, Abhishek Kasturi, Frank Hu, Karan Soni, Derek Ho, Bryan H. Atwood, Lj Ristic, Xiaomeng Liu, and S. J. Koppal
SPIE OPTO 2022
PDF | VIDEO

2021

SaccadeCam: Adaptive Visual Attention for Monocular Depth Sensing
B. Tilmon and S. J. Koppal
International Conference on Computer Vision (ICCV) 2021
PROJECT PAGE | PDF

A Monolithic Forward-View Optical Scanner by a Pair of Upright MEMS Mirrors on a SiOB for LiDAR Applications
D. Wang, D. Zheng, S. J. Koppal, B. Sun, and H. Xie
Journal of Microelectromechanical Systems
PDF

Dense Lissajous Sampling and Interpolation for Dynamic Light-Transport
X. Liu, K. Henderson, J. Rego, S. Jayasuriya and S. J. Koppal
Optics Express 2021
PDF

A Miniature LiDAR with a Detached MEMS Scanner for Micro-robotics
D. Wang, H. Xie, L. Thomas and S. J. Koppal
IEEE Sensors Journal 2021
PDF

Fast Foveating Cameras for Dense Adaptive Resolution
B. Tilmon, E. Jain, S. Ferrari and S. J. Koppal
IEEE Transactions on Pattern Analysis and Machine Intelligence (PAMI) 2021
PDF

Design and Fabrication of a Forward View Scanner on SIOB with Latch Structure for Improved Vertical Orientation
D. Wang, D. Zheng, S. J. Koppal, B. Sun and H. Xie
IEEE International Conference on Micro Electrical Mechanical Systems (MEMS) 2021
PDF

2020

Towards a MEMS-based Adaptive LIDAR
F. Pittaluga, Z. Tasneem, J. Folden, B. Tilmon, A. Chakrabarti and S. J. Koppal
International Conference on 3D Vision (3DV) 2020
PROJECT PAGE | PDF

Adaptive Fovea for Scanning Depth Sensors
Z. Tasneem, C. Adhivarahan, D. Wang, H. Xie, K. Dantu and S. J. Koppal
International Journal of Robotics Research (IJRR) 2020
PDF

A MEMS-Based Foveating Lidar to Enable Real-Time Adaptive Depth Sensing
F. Pittaluga, Z. Tasneem, J. Folden, B. Tilmon, A. Chakrabarti and S. J. Koppal
arXiv 2020
PROJECT PAGE | PDF

FoveaCam: A MEMS Mirror-Enabled Foveating Camera
B. Tilmon, E. Jain, S. Ferrari, and S. J. Koppal
International Conference on Computational Photography (ICCP) 2020
PROJECT PAGE | CODE | PDF

Design and Calibration of a Fast Flying-Dot Projector for Dynamic Light Transport Acquisition
K. Henderson, X. Liu, J. Folden, B. Tilmon, S. Jayasuriya, and S. J. Koppal
Transactions on Computational Imaging (TCI) 2020
PROJECT PAGE | PDF

Proximity-based Sensor Fusion of Depth Cameras and Isotropic Rad-detectors
K. Henderson, X. Liu, K. Stadnikia, A. Martin, A. Enqvist, and S. J. Koppal
Transactions on Nuclear Science 2020
PDF

The Security-Utility Trade-off for Iris Authentication and Eye Animation for Social Virtual Avatars
B. John, S. Joerg, S. J. Koppal and E. Jain
IEEE VR 2020
PDF

A low-voltage, low-current, digital-driven MEMS mirror for low-power LiDAR
D. Wang, L. Thomas, S. J. Koppal, Y. Ding, H. Xie
IEEE Sensors Letters 2020
PDF

A Monolithic Forward-View MEMS Laser Scanner With Decoupled Raster Scanning and Enlarged Scanning Angle for Micro LiDAR Applications
D. Wang, S. J. Koppal and H. Xie
Journal of Microelectromechanical Systems 2020
PDF

2019

A Compact Omnidirectional Laser Scanner Based on an Electrothermal Tripod MEMS Mirror for LiDAR
D. Wang, C. Watkins, S. J. Koppal, M. Li, Y. Ding and H. Xie
Transducers 2019
PDF

A Large Aperture 2-Axis Electrothermal MEMS Mirror for Compact 3-D LiDAR
D. Wang, C. Watkins, M. Aradhya, S. J. Koppal and H. Xie
International Conference on Optical MEMS and Nanophotonics (OMN) 2019
PDF

Revealing Scenes by Inverting Structure from Motion Reconstructions
Best Paper Finalist
F. Pittaluga, S. J. Koppal, S. Kang and S. Sinha
Conference on Computer Vision and Pattern Recognition (CVPR) 2019
PROJECT PAGE | PDF

EyeVEIL: Degrading Iris Authentication in Eye-Tracking Headsets
B. John, S. J. Koppal and E. Jain
ACM Symposium on Eye Tracking Research & Applications (ETRA) 2019
PDF

Learning Privacy Preserving Encodings through Adversarial Training
F. Pittaluga, S. J. Koppal, A. Chakrabarti
IEEE Winter Conference on Applications of Computer Vision (WACV) 2019
PDF

2018

Directionally Controlled Time-of-Flight Ranging for Mobile Sensing Platforms
Robotics: Science and Systems (RSS) 2018
Z. Tasneem, D. Wang, H. Xie and S. J. Koppal
PROJECT PAGE | PDF

An Integrated Forward-View 2-Axis MEMS Scanner for Compact 3D LIDAR
Winner of Best Student Paper Award
NEMS 2018
D.Wang*, S. S. Rojas, Al. Shuping, Z. Tasneem, S. J. Koppal, H. Xie*
PDF

A Compact 3D LIDAR Based on an Electrothermal Two-Axis MEMS Scanner for Small UAV
SPIE 2018
D. Wang, S. Strassle, A. Stainsby, Y. Bai, S. J. Koppal, et al.
PDF

Designing Light Filters to Detect Skin Using a Low-powered Sensor
SoutheastCon 2018
M. U. Tariq, A. K. Ghosh, K. Badillo-Urquiola, A. Jha, S. J. Koppal, and P. J. Wisniewski
PDF

Data Fusion for a Vision-Aided Radiological Detection System: Calibration Algorithm Performance
Nuclear Instruments and Methods in Physics A
K. Stadnikia, K. Henderson, A. Martin, P. Riley, S. J. Koppal, A. Enqvist
PDF

2017

Tracking Radioactive Sources through Sensor Fusion of Omnidirectional LIDAR and Isotropic Rad-detectors
3DV 2017
K. Henderson, K. Stadnikia, A. Martin, A. Enqvist, and S. J. Koppal
PROJECT PAGE | PDF

Focal Flow: Velocity and Depth from Differential Defocus through Motion
IJCV 2017
E. Alexander, Q. Guo, S. J. Koppal, S.J. Gortler, and T. Zickler
PDF

Situational Information Guidance for Revised Detection Limits
Nuclear Science Symposium/Medical Imaging Conference 2017
K. Stadnikia, K. Henderson, S. J. Koppal and A. Enqvist
PDF

A Compact MEMS-Based Wide-Angle Optical Scanner
OMN 2017
B. Yang, L. Zhou, X. Zhang, D. Wang, S. J. Koppal and H. Xie
PDF

Creating Segments and Effects on Comics by Clustering Gaze Data
Transactions on Multimedia Computing (TOMM), 2017
I. Thirunarayan, K. Khetarpal, S.J. Koppal, O. LeMeur, J. Shea, E. Jain
PROJECT PAGE | PDF

Pre-Capture Privacy for Small Vision Sensors
IEEE Transactions on Pattern Analysis and Machine Intelligence, 2017
F. Pittaluga and S.J. Koppal
PDF

2016

Focal Flow: Measuring Distance and Velocity with Defocus and Differential Motion.
Winner of Best Student Paper Award
European Conference on Computer Vision, 2016.
E. Alexander, Q. Guo, S.J. Koppal, S.J. Gortler, and T. Zickler
PDF

Leveraging Gaze Data for Segmentation and Effects on Comics.
ACM Symposium on Applied Perception Poster, 2016.
I. Thirunarayanan, S. J. Koppal, J. Shea, E. Jain
PROJECT PAGE | PDF

A Survey of Computational Photography in the Small.
IEEE Signal Processing Magazine, 2016.
S. J. Koppal
PDF

A Wide-angle Immersed MEMS Mirror and Its Application in Optical Coherence Tomography.
International Conference on Optical MEMS and Nanophotonics, 2016.
X. Zhang, L. Zhou, C. Duan, D. Zheng, S. J. Koppal, and H. Xie
PROJECT PAGE | PDF

Sensor-level Privacy for Thermal Cameras.
International Conference on Computational Photography, 2016.
F. Pittaluga, A. Zivkovic and S. J. Koppal
PDF

Wide-angle Structured Light with a Scanning MEMS Mirror in Liquid.
Optics Express 2016.
X. Zhang, S. J. Koppal, R. Zhang, L. Zhou, E. Butler, and H. Xie
PROJECT PAGE | PDF

2015

Low Power Depth and Velocity from a Passive Moving Sensors, 2015.
Extreme Imaging Workshop 2015.
E. Alexander, S. J. Koppal and T. Zickler
PDF

Low-Cost Depth and Radiological Sensor Fusion to Detect Moving Sources
3DV, 2015.
P. Riley, A. Enqvist and S. J. Koppal
PROJECT PAGE | PDF

Privacy Preserving Optics for Miniature Vision Sensors
Conference on Computer Vision and Pattern Recognition, 2015.
F. Pittaluga and S. J. Koppal
PDF

Data Fusion for a Vision-Radiological System for Source Tracking and Discovery
Advancements in Nuclear Instrumentation Measurement Methods and their Applic., 2015.
A. Enqvist and S. J. Koppal
PROJECT PAGE

Generalized Assorted Camera Arrays: Robust Cross-channel Registration and Applic.
Transactions on Image Processing, 2015.
J. Holloway, K. Mitra, S. J. Koppal and A. Veeraraghavan
PROJECT PAGE | PDF

MEMS Mirrors Submerged in Liquid for Wide-angle Scanning
International Conference on Solid-State Sensors, Actuators and Microsystems, 2015.
X. Zhang, R. Zhang, S. J. Koppal, L. Butler, X. Cheng and H. Xie
PROJECT PAGE | PDF

Beyond Perspective Dual Photography with Illumination Masks
Transactions on Image Processing, 2015.
S. J. Koppal and S. G. Narasimhan
PROJECT PAGE | PDF

2013

Towards wide-angle micro vision sensors
Transactions on Pattern Analysis and Machine Intelligence, 2013.
Invited paper for special issue
S. J. Koppal, I. Gkioulekas, T. Young, H. Park, K. Crozier, G. Barrows and T. Zickler
PROJECT PAGE | PDF

2012

A low-power structured light sensor for outdoor scene reconstruction and dominant material identification
International Workshop on Projector-Camera Systems, 2012.
C. Mertz, S. J. Koppal, S. Sia and S. G. Narasimhan
PROJECT PAGE | PDF

2011

Exploiting DLP illumination dithering for reconstruction and photography of high-speed scenes
International Journal on Computer Vision, 2011.
S. J. Koppal, S. Yamazaki and S. G. Narasimhan
PROJECT PAGE | PDF

A viewer-centric editor for stereoscopic cinema
IEEE Computer Graphics and Applications, 2011.
S. J. Koppal, L. Zitnick, M. Cohen, S. Kang, B. Ressler and A. Colburn
PROJECT PAGE | PDF

Wide-angle micro sensors for vision on a tight budget
Conference on Computer Vision and Pattern Recognition, 2011.
Oral Presentation, 4% acceptance rate
S. J. Koppal, I. Gkioulekas, T. Zickler and G. Barrows
PROJECT PAGE | PDF

2009

Shadow cameras: Reciprocal views from illumination masks
International Conference on Computer Vision, 2009.
Poster Presentation, 20% acceptance rate
S. J. Koppal and S. G. Narasimhan
PROJECT PAGE | PDF

2008

Temporal dithering of illumination for fast active vision
European Conference on Computer Vision, 2008.
Oral Presentation, 4% acceptance rate
S. G. Narasimhan, S. J. Koppal and S. Yamazaki
PROJECT PAGE | PDF

Illustrating motion through DLP photography
International Workshop on Projector-Camera Systems, 2008.
S. J. Koppal and S. G. Narasimhan
PROJECT PAGE | PDF

Appearance derivatives for iso-normal clustering of scenes
Transactions on Pattern Analysis and Machine Intelligence, 2008.
S. J. Koppal and S. G. Narasimhan
PROJECT PAGE | PDF

2007

Novel depth cues from uncalibrated near-field lighting
International Conference on Computer Vision, 2007.
Poster Presentation, 20% acceptance rate
S. J. Koppal and S. G. Narasimhan
PROJECT PAGE | PDF

2006

Clustering appearance for scene analysis
Conference on Computer Vision and Pattern Recognition, 2006.
Oral Presentation, 4% acceptance rate
S. J. Koppal and S. G. Narasimhan
PROJECT PAGE | PDF

Taylor series of appearance functions
CMU-Robotics Institute Technical report, 2006.
S. J. Koppal, A. Datta, S. G. Narasimhan and K. Nishino

2005

Structured light from scattering media
International Conference on Computer Vision, 2005.
Oral Presentation, 4% acceptance rate
S. G. Narasimhan, S. K. Nayar, B. Sun and S. J. Koppal
PROJECT PAGE