Andrés Bruhn - RankMe

115 papers A* 5A 10B 5C 2Journal 44Unranked 44

Year	Rank	Type	Title / Venue / Authors
2025	J	`jnl`	FlowBench: Benchmarking Optical Flow Estimation Methods for Reliability and Generalization. Trans. Mach. Learn. Res. Shashank Agnihotri, Julian Yuya Caspary, Luca Schwarz, Xinyan Gao, Jenny Schmalfuss, Andrés Bruhn, Margret Keuper
2025	J	`jnl`	MS-RAFT-3D: A Multi-Scale Architecture for Recurrent Image-Based Scene Flow. CoRR Jakob Schmid, Azin Jahedi, Noah Berenguel Senn, Andrés Bruhn
2025	—	`conf`	On the Generalization of Optical Flow: Quantifying Robustness to Dataset Shifts. ICCVW Katrin Bauer, Andrés Bruhn, Jenny Schmalfuss
2025	A*	`conf`	PARC: A Quantitative Framework Uncovering the Symmetries within Vision Language Models. CVPR Jenny Schmalfuss, Nadine Chang, Vibashan VS, Maying Shen, Andrés Bruhn, José M. Álvarez
2025	J	`jnl`	PARC: A Quantitative Framework Uncovering the Symmetries within Vision Language Models. CoRR Jenny Schmalfuss, Nadine Chang, Vibashan VS, Maying Shen, Andrés Bruhn, José M. Álvarez
2025	J	`jnl`	RobustSpring: Benchmarking Robustness to Image Corruptions for Optical Flow, Scene Flow and Stereo. CoRR Jenny Schmalfuss, Victor Oei, Lukas Mehl, Madlen Bartsch, Shashank Agnihotri, Margret Keuper, Andrés Bruhn
2024	A	`conf`	CCMR: High Resolution Optical Flow Estimation via Coarse-to-Fine Context-Guided Motion Reasoning. WACV Azin Jahedi, Maximilian Luz, Marc Rivinius, Andrés Bruhn
2024	A	`conf`	Detection Defenses: An Empty Promise against Adversarial Patch Attacks on Optical Flow. WACV Erik Scheurer, Jenny Schmalfuss, Alexander Lis, Andrés Bruhn
2024	J	`jnl`	MS-RAFT+: High Resolution Multi-Scale RAFT. Int. J. Comput. Vis. Azin Jahedi, Maximilian Luz, Marc Rivinius, Lukas Mehl, Andrés Bruhn
2024	A	`conf`	Stereo Conversion with Disparity-Aware Warping, Compositing and Inpainting. WACV Lukas Mehl, Andrés Bruhn, Markus Gross, Christopher Schroers
2023	J	`jnl`	Blind Image Inpainting with Sparse Directional Filter Dictionaries for Lightweight CNNs. J. Math. Imaging Vis. Jenny Schmalfuss, Erik Scheurer, Heng Zhao, Nikolaos Karantzas, Andrés Bruhn, Demetrio Labate
2023	J	`jnl`	CCMR: High Resolution Optical Flow Estimation via Coarse-to-Fine Context-Guided Motion Reasoning. CoRR Azin Jahedi, Maximilian Luz, Marc Rivinius, Andrés Bruhn
2023	J	`jnl`	Detection Defenses: An Empty Promise against Adversarial Patch Attacks on Optical Flow. CoRR Erik Scheurer, Jenny Schmalfuss, Alexander Lis, Andrés Bruhn
2023	A*	`conf`	Distracting Downpour: Adversarial Weather Attacks for Motion Estimation. ICCV Jenny Schmalfuss, Lukas Mehl, Andrés Bruhn
2023	J	`jnl`	Distracting Downpour: Adversarial Weather Attacks for Motion Estimation. CoRR Jenny Schmalfuss, Lukas Mehl, Andrés Bruhn
2023	A	`conf`	M-FUSE: Multi-frame Fusion for Scene Flow Estimation. WACV Lukas Mehl, Azin Jahedi, Jenny Schmalfuss, Andrés Bruhn
2023	A*	`conf`	Spring: A High-Resolution High-Detail Dataset and Benchmark for Scene Flow, Optical Flow and Stereo. CVPR Lukas Mehl, Jenny Schmalfuss, Azin Jahedi, Yaroslava Nalivayko, Andrés Bruhn
2023	J	`jnl`	Spring: A High-Resolution High-Detail Dataset and Benchmark for Scene Flow, Optical Flow and Stereo. CoRR Lukas Mehl, Jenny Schmalfuss, Azin Jahedi, Yaroslava Nalivayko, Andrés Bruhn
2022	J	`jnl`	A Perturbation Constrained Adversarial Attack for Evaluating the Robustness of Optical Flow. CoRR Jenny Schmalfuss, Philipp Scholze, Andrés Bruhn
2022	—	`conf`	A Perturbation-Constrained Adversarial Attack for Evaluating the Robustness of Optical Flow. ECCV (22) Jenny Schmalfuss, Philipp Scholze, Andrés Bruhn
2022	J	`jnl`	Attacking Motion Estimation with Adversarial Snow. CoRR Jenny Schmalfuss, Lukas Mehl, Andrés Bruhn
2022	J	`jnl`	Blind Image Inpainting with Sparse Directional Filter Dictionaries for Lightweight CNNs. CoRR Jenny Schmalfuss, Erik Scheurer, Heng Zhao, Nikolaos Karantzas, Andrés Bruhn, Demetrio Labate
2022	J	`jnl`	Efficient and Robust Background Modeling with Dynamic Mode Decomposition. J. Math. Imaging Vis. Tim Krake, Andrés Bruhn, Bernhard Eberhardt, Daniel Weiskopf
2022	—	`conf`	From Chairs To Brains: Customizing Optical Flow For Surgical Activity Localization. ISBI Markus Philipp, Neal Bacher, Stefan Saur, Franziska Mathis-Ullrich, Andrés Bruhn
2022	J	`jnl`	High Resolution Multi-Scale RAFT (Robust Vision Challenge 2022). CoRR Azin Jahedi, Maximilian Luz, Lukas Mehl, Marc Rivinius, Andrés Bruhn
2022	J	`jnl`	M-FUSE: Multi-frame Fusion for Scene Flow Estimation. CoRR Lukas Mehl, Azin Jahedi, Jenny Schmalfuss, Andrés Bruhn
2022	J	`jnl`	Multi-Scale RAFT: Combining Hierarchical Concepts for Learning-based Optical FLow Estimation. CoRR Azin Jahedi, Lukas Mehl, Marc Rivinius, Andrés Bruhn
2022	B	`conf`	Multi-Scale Raft: Combining Hierarchical Concepts for Learning-Based Optical Flow Estimation. ICIP Azin Jahedi, Lukas Mehl, Marc Rivinius, Andrés Bruhn
2021	—	`conf`	An Anisotropic Selection Scheme for Variational Optical Flow Methods with Order-Adaptive Regularisation. SSVM Lukas Mehl, Cedric Beschle, Andrea Barth, Andrés Bruhn
2020	J	`jnl`	Subjective Annotation for a Frame Interpolation Benchmark using Artifact Amplification. CoRR Hui Men, Vlad Hosu, Hanhe Lin, Andrés Bruhn, Dietmar Saupe
2020	J	`jnl`	Subjective annotation for a frame interpolation benchmark using artefact amplification. Qual. User Exp. Hui Men, Vlad Hosu, Hanhe Lin, Andrés Bruhn, Dietmar Saupe
2020	B	`conf`	Visual Analytics and Annotation of Pervasive Eye Tracking Video. ETRA Kuno Kurzhals, Nils Rodrigues, Maurice Koch, Michael Stoll, Andrés Bruhn, Andreas Bulling, Daniel Weiskopf
2020	B	`conf`	Visual Quality Assessment for Interpolated Slow-Motion Videos Based on a Novel Database. QoMEX Hui Men, Vlad Hosu, Hanhe Lin, Andrés Bruhn, Dietmar Saupe
2019	—	`ed.`	Pattern Recognition - 40th German Conference, GCPR 2018, Stuttgart, Germany, October 9-12, 2018, Proceedings GCPR Thomas Brox, Andrés Bruhn, Mario Fritz
2019	J	`jnl`	Technical Report on Visual Quality Assessment for Frame Interpolation. CoRR Hui Men, Hanhe Lin, Vlad Hosu, Daniel Maurer, Andrés Bruhn, Dietmar Saupe
2019	B	`conf`	Visual Quality Assessment for Motion Compensated Frame Interpolation. QoMEX Hui Men, Hanhe Lin, Vlad Hosu, Daniel Maurer, Andrés Bruhn, Dietmar Saupe
2018	J	`jnl`	Combining Shape from Shading and Stereo: A Joint Variational Method for Estimating Depth, Illumination and Albedo. Int. J. Comput. Vis. Daniel Maurer, Yong Chul Ju, Michael Breuß, Andrés Bruhn
2018	A	`conf`	Directional Priors for Multi-Frame Optical Flow. BMVC Daniel Maurer, Michael Stoll, Andrés Bruhn
2018	A	`conf`	ProFlow: Learning to Predict Optical Flow. BMVC Daniel Maurer, Andrés Bruhn
2018	J	`jnl`	ProFlow: Learning to Predict Optical Flow. CoRR Daniel Maurer, Andrés Bruhn
2018	—	`conf`	Structure-from-Motion-Aware PatchMatch for Adaptive Optical Flow Estimation. ECCV (8) Daniel Maurer, Nico Marniok, Bastian Goldluecke, Andrés Bruhn
2017	—	`conf`	A Comparison of Isotropic and Anisotropic Second Order Regularisers for Optical Flow. SSVM Daniel Maurer, Michael Stoll, Sebastian Volz, Patrick Gairing, Andrés Bruhn
2017	—	`conf`	A Time-Efficient Optimisation Framework for Parameters of Optical Flow Methods. SCIA (1) Michael Stoll, Sebastian Volz, Daniel Maurer, Andrés Bruhn
2017	—	`conf`	FlowBrush: optical flow art. CAe@Expressive Kuno Kurzhals, Michael Stoll, Andrés Bruhn, Daniel Weiskopf
2017	—	`conf`	Illumination-Aware Large Displacement Optical Flow. EMMCVPR Michael Stoll, Daniel Maurer, Sebastian Volz, Andrés Bruhn
2017	—	`conf`	Order-Adaptive Regularisation for Variational Optical Flow: Global, Local and in Between. SSVM Daniel Maurer, Michael Stoll, Andrés Bruhn
2017	A	`conf`	Order-Adaptive and Illumination-Aware Variational Optical Flow Refinement. BMVC Daniel Maurer, Michael Stoll, Andrés Bruhn
2017	—	`conf`	Variational Large Displacement Optical Flow Without Feature Matches. EMMCVPR Michael Stoll, Daniel Maurer, Andrés Bruhn
2016	A	`conf`	Combining Shape from Shading and Stereo: A Variational Approach for the Joint Estimation of Depth, Illumination and Albedo. BMVC Daniel Maurer, Yong Chul Ju, Michael Breuß, Andrés Bruhn
2016	J	`jnl`	Cyclic Schemes for PDE-Based Image Analysis. Int. J. Comput. Vis. Joachim Weickert, Sven Grewenig, Christopher Schroers, Andrés Bruhn
2016	—	`ch.`	Direct Variational Perspective Shape from Shading with Cartesian Depth Parametrisation. Perspectives in Shape Analysis Yong Chul Ju, Daniel Maurer, Michael Breuß, Andrés Bruhn
2015	—	`conf`	An Efficient Linearisation Approach for Variational Perspective Shape from Shading. GCPR Daniel Maurer, Yong Chul Ju, Michael Breuß, Andrés Bruhn
2015	J	`jnl`	Direct Variational Perspective Shape from Shading with Cartesian Depth Parametrisation. CoRR Yong Chul Ju, Daniel Maurer, Michael Breuß, Andrés Bruhn
2015	—	`conf`	Variational Perspective Shape from Shading. SSVM Yong Chul Ju, Andrés Bruhn, Michael Breuß
2015	J	`jnl`	Vision for Autonomous Vehicles and Probes (Dagstuhl Seminar 15461). Dagstuhl Reports Andrés Bruhn, Atsushi Imiya, Ales Leonardis, Tomás Pajdla
2014	—	`ed.`	Efficient Algorithms for Global Optimization Methods in Computer Vision - International Dagstuhl Seminar, Dagstuhl Castle, Germany, November 20-25, 2011, Revised Selected Papers Efficient Algorithms for Global Optimization Methods in Computer Vision Andrés Bruhn, Thomas Pock, Xue-Cheng Tai
2014	—	`conf`	Learning Brightness Transfer Functions for the Joint Recovery of Illumination Changes and Optical Flow. ECCV (1) Oliver Demetz, Michael Stoll, Sebastian Volz, Joachim Weickert, Andrés Bruhn
2014	J	`jnl`	Understanding, Optimising, and Extending Data Compression with Anisotropic Diffusion. Int. J. Comput. Vis. Christian Schmaltz, Pascal Peter, Markus Mainberger, Franziska Ebel, Joachim Weickert, Andrés Bruhn
2013	—	`conf`	Generalised Perspective Shape from Shading in Spherical Coordinates. SSVM Silvano Galliani, Yong Chul Ju, Michael Breuß, Andrés Bruhn
2013	A	`conf`	Generalised Perspective Shape from Shading with Oren-Nayar Reflectance. BMVC Yong Chul Ju, Silvia Tozza, Michael Breuß, Andrés Bruhn, Andreas Kleefeld
2013	B	`conf`	Joint trilateral filtering for multiframe optical flow. ICIP Michael Stoll, Sebastian Volz, Andrés Bruhn
2012	—	`conf`	Adaptive Integration of Feature Matches into Variational Optical Flow Methods. ACCV (3) Michael Stoll, Sebastian Volz, Andrés Bruhn
2012	—	`conf`	Anisotropic Range Image Integration. DAGM/OAGM Symposium Christopher Schroers, Henning Zimmer, Levi Valgaerts, Andrés Bruhn, Oliver Demetz, Joachim Weickert
2012	J	`jnl`	Dense versus Sparse Approaches for Estimating the Fundamental Matrix. Int. J. Comput. Vis. Levi Valgaerts, Andrés Bruhn, Markus Mainberger, Joachim Weickert
2012	J	`jnl`	Lightweight binocular facial performance capture under uncontrolled lighting. ACM Trans. Graph. Levi Valgaerts, Chenglei Wu, Andrés Bruhn, Hans-Peter Seidel, Christian Theobalt
2012	—	`conf`	Motion Compensated Frame Interpolation with a Symmetric Optical Flow Constraint. ISVC (1) Lars Lau Rakêt, Lars Roholm, Andrés Bruhn, Joachim Weickert
2012	A	`conf`	Shape from Shading for Rough Surfaces: Analysis of the Oren-Nayar Model. BMVC Yong Chul Ju, Michael Breuß, Andrés Bruhn, Silvano Galliani
2011	J	`jnl`	Edge-based compression of cartoon-like images with homogeneous diffusion. Pattern Recognit. Markus Mainberger, Andrés Bruhn, Joachim Weickert, Søren Forchhammer
2011	J	`jnl`	Efficient Algorithms for Global Optimisation Methods in Computer Vision (Dagstuhl Seminar 11471). Dagstuhl Reports Andrés Bruhn, Thomas Pock, Xue-Cheng Tai
2011	J	`jnl`	Freehand HDR Imaging of Moving Scenes with Simultaneous Resolution Enhancement. Comput. Graph. Forum Henning Zimmer, Andrés Bruhn, Joachim Weickert
2011	A*	`conf`	Modeling temporal coherence for optical flow. ICCV Sebastian Volz, Andrés Bruhn, Levi Valgaerts, Henning Zimmer
2011	—	`conf`	Optic Flow Scale Space. SSVM Oliver Demetz, Joachim Weickert, Andrés Bruhn, Henning Zimmer
2011	J	`jnl`	Optic Flow in Harmony. Int. J. Comput. Vis. Henning Zimmer, Andrés Bruhn, Joachim Weickert
2011	—	`conf`	Theoretical Foundations of Gaussian Convolution by Extended Box Filtering. SSVM Pascal Gwosdek, Sven Grewenig, Andrés Bruhn, Joachim Weickert
2010	—	`conf`	A Highly Efficient GPU Implementation for Variational Optic Flow Based on the Euler-Lagrange Framework. ECCV Workshops (1) Pascal Gwosdek, Henning Zimmer, Sven Grewenig, Andrés Bruhn, Joachim Weickert
2010	J	`jnl`	Electrostatic Halftoning. Comput. Graph. Forum Christian Schmaltz, Pascal Gwosdek, Andrés Bruhn, Joachim Weickert
2010	—	`conf`	From Box Filtering to Fast Explicit Diffusion. DAGM-Symposium Sven Grewenig, Joachim Weickert, Andrés Bruhn
2010	—	`conf`	Joint Estimation of Motion, Structure and Geometry from Stereo Sequences. ECCV (4) Levi Valgaerts, Andrés Bruhn, Henning Zimmer, Joachim Weickert, Carsten Stoll, Christian Theobalt
2010	J	`jnl`	Variational optic flow on the Sony PlayStation 3 - Accurate dense flow fields for real-time applications. J. Real Time Image Process. Pascal Gwosdek, Andrés Bruhn, Joachim Weickert
2009	—	`conf`	Beating the Quality of JPEG 2000 with Anisotropic Diffusion. DAGM-Symposium Christian Schmaltz, Joachim Weickert, Andrés Bruhn
2009	—	`conf`	Complementary Optic Flow. EMMCVPR Henning Zimmer, Andrés Bruhn, Joachim Weickert, Levi Valgaerts, Agustín Salgado, Bodo Rosenhahn, Hans-Peter Seidel
2008	—	`conf`	A Variational Model for the Joint Recovery of the Fundamental Matrix and the Optical Flow. DAGM-Symposium Levi Valgaerts, Andrés Bruhn, Joachim Weickert
2008	J	`jnl`	Bewegungsschätzung in Echtzeit mit Optimierungsansätzen (Motion Estimation in Real-Time with Optimisation Methods). it Inf. Technol. Andrés Bruhn
2008	—	`conf`	Deinterlacing with Motion-Compensated Anisotropic Diffusion. Statistical and Geometrical Approaches to Visual Motion Analysis Matthias Ghodstinat, Andrés Bruhn, Joachim Weickert
2008	—	`conf`	High Performance Parallel Optical Flow Algorithms on the Sony Playstation 3. VMV Pascal Gwosdek, Andrés Bruhn, Joachim Weickert
2008	J	`jnl`	Image Compression with Anisotropic Diffusion. J. Math. Imaging Vis. Irena Galic, Joachim Weickert, Martin Welk, Andrés Bruhn, Alexander G. Belyaev, Hans-Peter Seidel
2008	—	`conf`	Is Dense Optic Flow Useful to Compute the Fundamental Matrix?. ICIAR Markus Mainberger, Andrés Bruhn, Joachim Weickert
2008	—	`conf`	PDE-Based Anisotropic Disparity-Driven Stereo Vision. VMV Henning Zimmer, Andrés Bruhn, Levi Valgaerts, Michael Breuß, Joachim Weickert, Bodo Rosenhahn, Hans-Peter Seidel
2007	—	`conf`	Beauty with Variational Methods: An Optic Flow Approach to Hairstyle Simulation. SSVM Oliver Demetz, Joachim Weickert, Andrés Bruhn, Martin Welk
2007	—	`conf`	Direct Shape-from-Shading with Adaptive Higher Order Regularisation. SSVM Oliver Vogel, Andrés Bruhn, Joachim Weickert, Stephan Didas
2007	—	`conf`	Illumination-Robust Variational Optical Flow with Photometric Invariants. DAGM-Symposium Yana Momchilova Mileva, Andrés Bruhn, Joachim Weickert
2007	J	`jnl`	Mathematical morphology for matrix fields induced by the Loewner ordering in higher dimensions. Signal Process. Bernhard Burgeth, Andrés Bruhn, Nils Papenberg, Martin Welk, Joachim Weickert
2007	J	`jnl`	Morphology for matrix data: Ordering versus PDE-based approach. Image Vis. Comput. Bernhard Burgeth, Andrés Bruhn, Stephan Didas, Joachim Weickert, Martin Welk
2007	—	`conf`	Robust Variational Reconstruction from Multiple Views. SCIA Natalia Slesareva, Thomas Bühler, Kai Uwe Hagenburg, Joachim Weickert, Andrés Bruhn, Zachi Karni, Hans-Peter Seidel
2006	J	`jnl`	A Multigrid Platform for Real-Time Motion Computation with Discontinuity-Preserving Variational Methods. Int. J. Comput. Vis. Andrés Bruhn, Joachim Weickert, Timo Kohlberger, Christoph Schnörr
2006	J	`jnl`	Highly Accurate Optic Flow Computation with Theoretically Justified Warping. Int. J. Comput. Vis. Nils Papenberg, Andrés Bruhn, Thomas Brox, Stephan Didas, Joachim Weickert
2006	—	`conf`	Variational Motion Segmentation with Level Sets. ECCV (1) Thomas Brox, Andrés Bruhn, Joachim Weickert
2006	—	`—`	Variationelle optische Flussberechnung - präzise Modellierung und effziente Numerik. Andrés Bruhn
2006	—	`ch.`	Variationsansätze zur Bewegungsschätzung: Präzise Modellierung und Effiziente Numerik. Ausgezeichnete Informatikdissertationen Andrés Bruhn
2005	—	`conf`	Discontinuity-Preserving Computation of Variational Optic Flow in Real-Time. Scale-Space Andrés Bruhn, Joachim Weickert, Timo Kohlberger, Christoph Schnörr
2005	J	`jnl`	Domain decomposition for variational optical-flow computation. IEEE Trans. Image Process. Timo Kohlberger, Christoph Schnörr, Andrés Bruhn, Joachim Weickert
2005	J	`jnl`	Lucas/Kanade Meets Horn/Schunck: Combining Local and Global Optic Flow Methods. Int. J. Comput. Vis. Andrés Bruhn, Joachim Weickert, Christoph Schnörr
2005	C	`conf`	Morphology for Higher-Dimensional Tensor Data Via Loewner Ordering. ISMM Bernhard Burgeth, Nils Papenberg, Andrés Bruhn, Martin Welk, Christian Feddern, Joachim Weickert
2005	—	`conf`	Optic Flow Goes Stereo: A Variational Method for Estimating Discontinuity-Preserving Dense Disparity Maps. DAGM-Symposium Natalia Slesareva, Andrés Bruhn, Joachim Weickert
2005	—	`conf`	Towards PDE-Based Image Compression. VLSM Irena Galic, Joachim Weickert, Martin Welk, Andrés Bruhn, Alexander G. Belyaev, Hans-Peter Seidel
2005	A*	`conf`	Towards Ultimate Motion Estimation: Combining Highest Accuracy with Real-Time Performance. ICCV Andrés Bruhn, Joachim Weickert
2005	J	`jnl`	Variational optical flow computation in real time. IEEE Trans. Image Process. Andrés Bruhn, Joachim Weickert, Christian Feddern, Timo Kohlberger, Christoph Schnörr
2004	—	`conf`	High Accuracy Optical Flow Estimation Based on a Theory for Warping. ECCV (4) Thomas Brox, Andrés Bruhn, Nils Papenberg, Joachim Weickert
2004	J	`jnl`	High performance cluster computing with 3-D nonlinear diffusion filters. Real Time Imaging Andrés Bruhn, Tobias Jakob, Markus Fischer, Timo Kohlberger, Joachim Weickert, Ulrich Brüning, Christoph Schnörr
2004	—	`conf`	Parallel Variational Motion Estimation by Domain Decomposition and Cluster Computing. ECCV (4) Timo Kohlberger, Christoph Schnörr, Andrés Bruhn, Joachim Weickert
2003	—	`conf`	Domain Decomposition for Parallel Variational Optical Flow Computation. DAGM-Symposium Timo Kohlberger, Christoph Schnörr, Andrés Bruhn, Joachim Weickert
2003	—	`conf`	Low Level Parallelization of Nonlinear Diffusion Filtering Algorithms for Cluster Computing Environments. Euro-Par David Slogsnat, Markus Fischer, Andrés Bruhn, Joachim Weickert, Ulrich Brüning
2003	C	`conf`	Real-Time Optic Flow Computation with Variational Methods. CAIP Andrés Bruhn, Joachim Weickert, Christian Feddern, Timo Kohlberger, Christoph Schnörr
2002	—	`conf`	Combining the Advantages of Local and Global Optic Flow Methods. DAGM-Symposium Andrés Bruhn, Joachim Weickert, Christoph Schnörr
2002	—	`conf`	Designing 3-D Nonlinear Diffusion Filters for High Performance Cluster Computing. DAGM-Symposium Andrés Bruhn, Tobias Jakob, Markus Fischer, Timo Kohlberger, Joachim Weickert, Ulrich Brüning, Christoph Schnörr