mtybilly/Instruct2DS huggingface dataset:
Factorized Bilinear Models for Image Recognition
Authors: Naiyan Wang, Jiaying Liu, Xiaodi Hou Yanghao Li
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: Although Deep Convolutional Neural Networks (CNNs) have liberated their power in various computer vision tasks, the most important components of CNN, convolutional layers and fully connected layers, are still limited to linear transformations. In this paper, we propose a novel Factorized Bilinear (FB) layer to model the pairwise feature interactions by considering the quadratic terms in the transformations. Compared with existing methods that tried to incorporate complex non-linearity structures into CNNs, the factorized parameterization makes our FB layer only require a linear increase of parameters and affordable computational cost. To further reduce the risk of overfitting of the FB layer, a specific remedy called DropFactor is devised during the training process. We also analyze the connection between FB layer and some existing models, and show FB layer is a generalization to them. Finally, we validate the effectiveness of FB layer on several widely adopted datasets including CIFAR-10, CIFAR-100 and ImageNet, and demonstrate superior results compared with various state-of-the-art deep models.
Octree Generating Networks: Efficient Convolutional Architectures for High-Resolution 3D Outputs
Authors: Alexey Dosovitskiy, Thomas Brox Maxim Tatarchenko
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: We present a deep convolutional decoder architecture that can generate volumetric 3D outputs in a compute- and memory-efficient manner by using an octree representation. The network learns to predict both the structure of the octree, and the occupancy values of individual cells. This makes it a particularly valuable technique for generating 3D shapes. In contrast to standard decoders acting on regular voxel grids, the architecture does not have cubic complexity. This allows representing much higher resolution outputs with a limited memory budget. We demonstrate this in several application domains, including 3D convolutional autoencoders, generation of objects and whole scenes from high-level representations, and shape from a single image.
Truncating Wide Networks Using Binary Tree Architectures
Authors: Mete Ozay, Shuohao Li, Takayuki Okatani Yan Zhang
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: In this paper, we propose a binary tree architecture to truncate architecture of wide networks by reducing the width of the networks. More precisely, in the proposed architecture, the width is incrementally reduced from lower layers to higher layers in order to increase the expressive capacity of networks with a less increase on parameter size. Also, in order to ease the gradient vanishing problem, features obtained at different layers are concatenated to form the output of our architecture. By employing the proposed architecture on a baseline wide network, we can construct and train a new network with same depth but considerably less number of parameters. In our experimental analyses, we observe that the proposed architecture enables us to obtain better parameter size and accuracy trade-off compared to baseline networks using various benchmark image classification datasets. The results show that our model can decrease the classification error of a baseline from 20.43% to 19.22% on Cifar-100 using only 28% of parameters that the baseline has.
Bringing Background Into the Foreground: Making All Classes Equal in Weakly-Supervised Video Semantic Segmentation
Authors: Mohammad Sadegh Aliakbarian, Mathieu Salzmann, Lars Petersson, Jose M. Alvarez Fatemeh Sadat Saleh
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: Pixel-level annotations are expensive and time-consuming to obtain. Hence, weak supervision using only image tags could have a significant impact in semantic segmentation. Recent years have seen great progress in weakly-supervised semantic segmentation, whether from a single image or from videos. However, most existing methods are designed to handle a single background class. In practical applications, such as autonomous navigation, it is often crucial to reason about multiple background classes. In this paper, we introduce an approach to doing so by making use of classifier heatmaps. We then develop a two-stream deep architecture that jointly leverages appearance and motion, and design a loss based on our heatmaps to train it. Our experiments demonstrate the benefits of our classifier heatmaps and of our two-stream architecture on challenging urban scene datasets and on the YouTube-Objects benchmark, where we obtain state-of-the-art results.
View Adaptive Recurrent Neural Networks for High Performance Human Action Recognition From Skeleton Data
Authors: Cuiling Lan, Junliang Xing, Wenjun Zeng, Jianru Xue, Nanning Zheng Pengfei Zhang
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: Skeleton-based human action recognition has recently attracted increasing attention due to the popularity of 3D skeleton data. One main challenge lies in the large view variations in captured human actions. We propose a novel view adaptation scheme to automatically regulate observation viewpoints during the occurrence of an action. Rather than re-positioning the skeletons based on a human defined prior criterion, we design a view adaptive recurrent neural network (RNN) with LSTM architecture, which enables the network itself to adapt to the most suitable observation viewpoints from end to end. Extensive experiment analyses show that the proposed view adaptive RNN model strives to (1) transform the skeletons of various views to much more consistent viewpoints and (2) maintain the continuity of the action rather than transforming every frame to the same position with the same body orientation. Our model achieves significant improvement over the state-of-the-art approaches on three benchmark datasets.
Joint Discovery of Object States and Manipulation Actions
Authors: Ivan Laptev, Josef Sivic, Simon Lacoste-Julien Jean-Baptiste Alayrac
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: Many human activities involve object manipulations aiming to modify the object state. Examples of common state changes include full/empty bottle, open/closed door, and attached/detached car wheel. In this work, we seek to automatically discover the states of objects and the associated manipulation actions. Given a set of videos for a particular task, we propose a joint model that learns to identify object states and to localize state-modifying actions. Our model is formulated as a discriminative clustering cost with constraints. We assume a consistent temporal order for the changes in object states and manipulation actions, and introduce new optimization techniques to learn model parameters without additional supervision. We demonstrate successful discovery of seven manipulation actions and corresponding object states on a new dataset of videos depicting real-life object manipulations. We show that our joint formulation results in an improvement of object state discovery by action recognition and vice versa.
What Actions Are Needed for Understanding Human Actions in Videos?
Authors: Olga Russakovsky, Abhinav Gupta Gunnar A. Sigurdsson
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: What is the right way to reason about human activities? What directions forward are most promising? In this work, we analyze the current state of human activity understanding in videos. The goal of this paper is to examine datasets, evaluation metrics, algorithms, and potential future directions. We look at the qualitative attributes that define activities such as pose variability, brevity, and density. The experiments consider multiple state-of-the-art algorithms and multiple datasets. The results demonstrate that while there is inherent ambiguity in the temporal extent of activities, current datasets still permit effective benchmarking. We discover that fine-grained understanding of objects and pose when combined with temporal reasoning is likely to yield substantial improvements in algorithmic accuracy. We present the many kinds of information that will be needed to achieve substantial gains in activity understanding: objects, verbs, intent, and sequential reasoning. The software and additional information will be made available to provide other researchers detailed diagnostics to understand their own algorithms.
Lattice Long Short-Term Memory for Human Action Recognition
Authors: Kui Jia, Kevin Chen, Dit-Yan Yeung, Bertram E. Shi, Silvio Savarese Lin Sun
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: Human actions captured in video sequences are three-dimensional signals characterizing visual appearance and motion dynamics. To learn action patterns, existing methods adopt Convolutional and/or Recurrent Neural Networks (CNNs and RNNs). CNN based methods are effective in learning spatial appearances, but are limited in modeling long-term motion dynamics. RNNs, especially Long Short-Term Memory (LSTM), are able to learn temporal motion dynamics. However, naively applying RNNs to video sequences in a convolutional manner implicitly assumes that motions in videos are stationary across different spatial locations. This assumption is valid for short-term motions but invalid when the duration of the motion is long. In this work, we propose Lattice-LSTM, which extends LSTM by learning independent hidden state transitions of memory cells for individual spatial locations. This method effectively enhances the ability to model dynamics across time and addresses the non-stationary issue of long-term motion dynamics without significantly increasing the model complexity. Additionally, we introduce a novel multi-modal training procedure for training our network. Unlike traditional two-stream architectures which use RGB and optical flow information as input, our two-stream model leverages both modalities to jointly train both input gates and both forget gates in the network rather than treating the two streams as separate entities with no information about the other. We apply this end-to-end system to benchmark datasets (UCF-101 and HMDB-51) of human action recognition. Experiments show that on both datasets, our proposed method outperforms all existing ones that are based on LSTM and/or CNNs of similar model complexities.
Common Action Discovery and Localization in Unconstrained Videos
Authors: Junsong Yuan Jiong Yang
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: Similar to common object discovery in images or videos, it is of great interests to discover and locate common actions in videos, which can benefit many video analytics applications such as video summarization, search, and understanding. In this work, we tackle the problem of common action discovery and localization in unconstrained videos, where we do not assume to know the types, numbers or locations of the common actions in the videos. Furthermore, each video can contain zero, one or several common action instances. To perform automatic discovery and localization in such challenging scenarios, we first generate action proposals using human prior. By building an affinity graph among all action proposals, we formulate the common action discovery as a subgraph density maximization problem to select the proposals containing common actions. To avoid enumerating in the exponentially large solution space, we propose an efficient polynomial time optimization algorithm. It solves the problem up to a user specified error bound with respect to the global optimal solution. The experimental results on several datasets show that even without any prior knowledge of common actions, our method can robustly locate the common actions in a collection of videos.
Pixel-Level Matching for Video Object Segmentation Using Convolutional Neural Networks
Authors: Francois Rameau, Junsik Kim, Seokju Lee, Seunghak Shin, In So Kweon Jae Shin Yoon
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: We propose a novel video object segmentation algorithm based on pixel-level matching using Convolutional Neural Networks (CNN). Our network aims to distinguish the target area from the background on the basis of the pixel-level similarity between two object units. The proposed network represents a target object using features from different depth layers in order to take advantage of both the spatial details and the category-level semantic information. Furthermore, we propose a feature compression technique that drastically reduces the memory requirements while maintaining the capability of feature representation. Two-stage training (pre-training and fine-tuning) allows our network to handle any target object regardless of its category (even if the object's type does not belong to the pre-training data) or of variations in its appearance through a video sequence. Experiments on large datasets demonstrate the effectiveness of our model - against related methods - in terms of accuracy, speed, and stability. Finally, we introduce the transferability of our network to different domains, such as the infrared data domain.
Am I a Baller? Basketball Performance Assessment From First-Person Videos
Authors: Hyun Soo Park, Stella X. Yu, Jianbo Shi Gedas Bertasius
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: This paper presents a method to assess a basketball player's performance from his/her first-person video. A key challenge lies in the fact that the evaluation metric is highly subjective and specific to a particular evaluator. We leverage the first-person camera to address this challenge. The spatiotemporal visual semantics provided by a first-person view allows us to reason about the camera wearer's actions while he/she is participating in an unscripted basketball game. Our method takes a player's first-person video and provides a player's performance measure that is specific to an evaluator's preference. To achieve this goal, we first use a convolutional LSTM network to detect atomic basketball events from first-person videos. Our network's ability to zoom-in to the salient regions addresses the issue of a severe camera wearer's head movement in first-person videos. The detected atomic events are then passed through the Gaussian mixtures to construct a highly non-linear visual spatiotemporal basketball assessment feature. Finally, we use this feature to learn a basketball assessment model from pairs of labeled first-person basketball videos, for which a basketball expert indicates, which of the two players is better. We demonstrate that despite not knowing the basketball evaluator's criterion, our model learns to accurately assess the players in real-world games. Furthermore, our model can also discover basketball events that contribute positively and negatively to a player's performance.
Deep Cropping via Attention Box Prediction and Aesthetics Assessment
Authors: Jianbing Shen Wenguan Wang
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: We model the photo cropping problem as a cascade of attention box regression and aesthetic quality classification, based on deep learning. A neural network is designed that has two branches for predicting attention bounding box and analyzing aesthetics, respectively. The predicted attention box is treated as an initial crop window where a set of cropping candidates are generated around it, without missing important information. Then, aesthetics assessment is employed to select the final crop as the one with the best aesthetic quality. With our network, cropping candidates share features within full-image convolutional feature maps, thus avoiding repeated feature computation and leading to higher computation efficiency. Via leveraging rich data for attention prediction and aesthetics assessment, the proposed method produces high-quality cropping results, even with the limited availability of training data for photo cropping. The experimental results demonstrate the competitive results and fast processing speed (5 fps with all steps).
Raster-To-Vector: Revisiting Floorplan Transformation
Authors: Jiajun Wu, Pushmeet Kohli, Yasutaka Furukawa Chen Liu
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: This paper addresses the problem of converting a rasterized floorplan image into a vector-graphics representation. Unlike existing approaches that rely on a sequence of low-level image processing heuristics, we adopt a learning-based approach. A neural architecture first transforms a rasterized image to a set of junctions that represent low-level geometric and semantic information (e.g., wall corners or door end-points). Integer programming is then formulated to aggregate junctions into a set of simple primitives (e.g., wall lines, door lines, or icon boxes) to produce a vectorized floorplan, while ensuring a topologically and geometrically consistent result. Our algorithm significantly outperforms existing methods and achieves around 90% precision and recall, getting to the range of production-ready performance. The vector representation allows 3D model popup for better indoor scene visualization, direct model manipulation for architectural remodeling, and further computational applications such as data analysis. Our system is efficient: we have converted hundred thousand production-level floorplan images into the vector representation and generated 3D popup models.
Deep TextSpotter: An End-To-End Trainable Scene Text Localization and Recognition Framework
Authors: Lukas Neumann, Jiri Matas Michal Busta
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: A method for scene text localization and recognition is proposed. The novelties include: training of both text detection and recognition in a single end-to-end pass, the structure of the recognition CNN and the geometry of its input layer that preserves the aspect of the text and adapts its resolution to the data. The proposed method achieves state-of-the-art accuracy in the end-to-end text recognition on two standard datasets - ICDAR 2013 and ICDAR 2015, whilst being an order of magnitude faster than competing methods - the whole pipeline runs at 10 frames per second on an NVidia K80 GPU.
Playing for Benchmarks
Authors: Zeeshan Hayder, Vladlen Koltun Stephan R. Richter
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: We present a benchmark suite for visual perception. The benchmark is based on more than 250K high-resolution video frames, all annotated with ground-truth data for both low-level and high-level vision tasks, including optical flow, semantic instance segmentation, object detection and tracking, object-level 3D scene layout, and visual odometry. Ground-truth data for all tasks is available for every frame. The data was collected while driving, riding, and walking a total of 184 kilometers in diverse ambient conditions in a realistic virtual world. To create the benchmark, we have developed a new approach to collecting ground-truth data from simulated worlds without access to their source code or content. We conduct statistical analyses that show that the composition of the scenes in the benchmark closely matches the composition of corresponding physical environments. The realism of the collected data is further validated via perceptual experiments. We analyze the performance of state-of-the-art methods for multiple tasks, providing reference baselines and highlighting challenges for future research.
Unpaired Image-To-Image Translation Using Cycle-Consistent Adversarial Networks
Authors: Taesung Park, Phillip Isola, Alexei A. Efros Jun-Yan Zhu
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: Image-to-image translation is a class of vision and graphics problems where the goal is to learn the mapping between an input image and an output image using a training set of aligned image pairs. However, for many tasks, paired training data will not be available. We present an approach for learning to translate an image from a source domain X to a target domain Y in the absence of paired examples. Our goal is to learn a mapping G: X -> Y such that the distribution of images from G(X) is indistinguishable from the distribution Y using an adversarial loss. Because this mapping is highly under-constrained, we couple it with an inverse mapping F: Y -> X and introduce a   cycle consistency loss  to push F(G(X)) ~ X (and vice versa). Qualitative results are presented on several tasks where paired training data does not exist, including collection style transfer, object transfiguration, season transfer, photo enhancement, etc. Quantitative comparisons against several prior methods demonstrate the superiority of our approach.
GANs for Biological Image Synthesis
Authors: Anatole Chessel, Rafael E. Carazo Salas, Federico Vaggi Anton Osokin
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: In this paper, we propose a novel application of Generative Adversarial Networks (GAN) to the synthesis of cells imaged by fluorescence microscopy. Compared to natural images, cells tend to have a simpler and more geometric global structure that facilitates image generation. However, the correlation between the spatial pattern of different fluorescent proteins reflects important biological functions, and synthesized images have to capture these relationships to be relevant for biological applications. We adapt GANs to the task at hand and propose new models with casual dependencies between image channels that can generate multi-channel images, which would be impossible to obtain experimentally. We evaluate our approach using two independent techniques and compare it against sensible baselines. Finally, we demonstrate that by interpolating across the latent space we can mimic the known changes in protein localization that occur through time during the cell cycle, allowing us to predict temporal evolution from static images.
Learning to Synthesize a 4D RGBD Light Field From a Single Image
Authors: Tongzhou Wang, Ashwin Sreelal, Ravi Ramamoorthi, Ren Ng Pratul P. Srinivasan
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: We present a machine learning algorithm that takes as input a 2D RGB image and synthesizes a 4D RGBD light field (color and depth of the scene in each ray direction). For training, we introduce the largest public light field dataset, consisting of over 3300 plenoptic camera light fields of scenes containing flowers and plants. Our synthesis pipeline consists of a convolutional neural network (CNN) that estimates scene geometry, a stage that renders a Lambertian light field using that geometry, and a second CNN that predicts occluded rays and non-Lambertian effects. Our algorithm builds on recent view synthesis methods, but is unique in predicting RGBD for each light field ray and improving unsupervised single image depth estimation by enforcing consistency of ray depths that should intersect the same scene point.
Neural EPI-Volume Networks for Shape From Light Field
Authors: Wei Yu, Thomas Pock Stefan Heber
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: This paper presents a novel deep regression network to extract geometric information from Light Field (LF) data. Our network builds upon u-shaped network architectures. Those networks involve two symmetric parts, an encoding and a decoding part. In the first part the network encodes relevant information from the given input into a set of high-level feature maps. In the second part the generated feature maps are then decoded to the desired output. To predict reliable and robust depth information the proposed network examines 3D subsets of the 4D LF called Epipolar Plane Image (EPI) volumes. An important aspect of our network is the use of 3D convolutional layers, that allow to propagate information from two spatial dimensions and one directional dimension of the LF. Compared to previous work this allows for an additional spatial regularization, which reduces depth artifacts and simultaneously maintains clear depth discontinuities. Experimental results show that our approach allows to create high-quality reconstruction results, which outperform current state-of-the-art Shape from Light Field (SfLF) techniques. The main advantage of the proposed approach is the ability to provide those high-quality reconstructions at a low computation time.
Material Editing Using a Physically Based Rendering Network
Authors: Duygu Ceylan, Ersin Yumer, Jimei Yang, Jyh-Ming Lien Guilin Liu
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: The ability to edit materials of objects in images is desirable by many content creators. However, this is an extremely challenging task as it requires to disentangle intrinsic physical properties of an image. We propose an end-to-end network architecture that replicates the forward image formation process to accomplish this task. Specifically, given a single image, the network first predicts intrinsic properties, i.e. shape, illumination, and material, which are then provided to a rendering layer. This layer performs in-network image synthesis, thereby enabling the network to understand the physics behind the image formation process. The proposed rendering layer is fully differentiable, supports both diffuse and specular materials, and thus can be applicable in a variety of problem settings. We demonstrate a rich set of visually plausible material editing examples and provide an extensive comparative study.
Turning Corners Into Cameras: Principles and Methods
Authors: Vickie Ye, Adam B. Yedidia, Fredo Durand, Gregory W. Wornell, Antonio Torralba, William T. Freeman Katherine L. Bouman
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: We show that walls and other obstructions with edges can be exploited as naturally-occurring "cameras" that reveal the hidden scenes beyond them. In particular, we demonstrate methods for using the subtle spatio-temporal radiance variations that arise on the ground at the base of edges to construct a one-dimensional video of the hidden scene. The resulting technique can be used for a variety of applications in diverse physical settings. From standard RGB video recordings of the variations in intensity, we use edge cameras to recover a 1-D video that reveals the number and trajectories of people moving in an occluded scene. We further show that adjacent vertical edges, such as those that arise in the case of an open doorway, yield a stereo camera from which the 2-D location of hidden, moving objects can be recovered. We demonstrate our technique in a number of indoor and outdoor environments involving varied surfaces and illumination conditions.
Linear Differential Constraints for Photo-Polarimetric Height Estimation
Authors: William A. P. Smith, Dizhong Zhu, Ravi Ramamoorthi, Edwin R. Hancock Silvia Tozza
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: In this paper we present a differential approach to photo-polarimetric shape estimation. We propose several alternative differential constraints based on polarisation and photometric shading information and show how to express them in a unified partial differential system. Our method uses the image ratios technique to combine shading and polarisation information in order to directly reconstruct surface height, without first computing surface normal vectors. Moreover, we are able to remove the non-linearities so that the problem reduces to solving a linear differential problem. We also introduce a new method for estimating a polarisation image from multichannel data and, finally, we show it is possible to estimate the illumination directions in a two source setup, extending the method into an uncalibrated scenario. From a numerical point of view, we use a least-squares formulation of the discrete version of the problem. To the best of our knowledge, this is the first work to consider a unified differential approach to solve photo-polarimetric shape estimation directly for height. Numerical results on synthetic and real-world data confirm the effectiveness of our proposed method.
Polynomial Solvers for Saturated Ideals
Authors: Kalle Astrom, Magnus Oskarsson Viktor Larsson
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: In this paper we present a new method for creating polynomial solvers for problems where a (possibly infinite) subset of the solutions are undesirable or uninteresting. These solutions typically arise from simplifications made during modeling, but can also come from degeneracies which are inherent to the geometry of the original problem. The proposed approach extends the standard action matrix method to saturated ideals. This allows us to add constraints that some polynomials should be non-zero on the solutions. This does not only offer the possibility of improved performance by removing superfluous solutions, but makes a larger class of problems tractable. Previously, problems with infinitely many solutions could not be solved directly using the action matrix method as it requires a zero-dimensional ideal. In contrast we only require that after removing the unwanted solutions only finitely many remain. We evaluate our method on three applications, optimal triangulation, time-of-arrival self-calibration and optimal vanishing point estimation.
Shape Inpainting Using 3D Generative Adversarial Network and Recurrent Convolutional Networks
Authors: Qiangui Huang, Suya You, Chao Yang, Ulrich Neumann Weiyue Wang
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: Recent advances in convolutional neural networks have shown promising results in 3D shape completion. But due to GPU memory limitations, these methods can only produce low-resolution outputs. To inpaint 3D models with semantic plausibility and contextual details, we introduce a hybrid framework that combines a 3D Encoder-Decoder Generative Adversarial Network (3D-ED-GAN) and a Long-term Recurrent Convolutional Network (LRCN). The 3D-ED-GAN is a 3D convolutional neural network trained with a generative adversarial paradigm to fill missing 3D data in low-resolution. LRCN adopts a recurrent neural network architecture to minimize GPU memory usage and incorporates an Encoder-Decoder pair into a Long Short-term Memory Network. By handling the 3D model as a sequence of 2D slices, LRCN transforms a coarse 3D shape into a more complete and higher resolution volume. While 3D-ED-GAN captures global contextual structure of the 3D shape, LRCN localizes the fine-grained details. Experimental results on both real-world and synthetic data show reconstructions from corrupted models result in complete and high-resolution 3D objects.
SurfaceNet: An End-To-End 3D Neural Network for Multiview Stereopsis
Authors: Juergen Gall, Haitian Zheng, Yebin Liu, Lu Fang Mengqi Ji
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: This paper proposes an end-to-end learning framework for multiview stereopsis. We term the network SurfaceNet. It takes a set of images and their corresponding camera parameters as input and directly infers the 3D model. The key advantage of the framework is that both photo-consistency as well geometric relations of the surface structure can be directly learned for the purpose of multiview stereopsis in an end-to-end fashion. SurfaceNet is a fully 3D convolutional network which is achieved by encoding the camera parameters together with the images in a 3D voxel representation. We evaluate SurfaceNet on the large-scale DTU benchmark.
Making Minimal Solvers for Absolute Pose Estimation Compact and Robust
Authors: Zuzana Kukelova, Yinqiang Zheng Viktor Larsson
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: In this paper we present new techniques for constructing compact and robust minimal solvers for absolute pose estimation. We focus on the P4Pfr problem, but the methods we propose are applicable to a more general setting. Previous approaches to P4Pfr suffer from artificial degeneracies which come from their formulation and not the geometry of the original problem. In this paper we show how to avoid these false degeneracies to create more robust solvers. Combined with recently published techniques for Grobner basis solvers we are also able to construct solvers which are significantly smaller. We evaluate our solvers on both real and synthetic data, and show improved performance compared to competing solvers. Finally we show that our techniques can be directly applied to the P3.5Pf problem to get a non-degenerate solver, which is competitive with the current state-of-the-art.
3D Surface Detail Enhancement From a Single Normal Map
Authors: Miaohui Wang, Xianbiao Qi, Lei Zhang Wuyuan Xie
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: In 3D reconstruction, the obtained surface details are mainly limited to the visual sensor due to sampling and quantization in the digitalization process. How to get a fine-grained 3D surface with low-cost is still a challenging obstacle in terms of experience, equipment and easy-to-obtain. This work introduces a novel framework for enhancing surfaces reconstructed from normal map, where the assumptions on hardware (e.g., photometric stereo setup) and reflection model (e.g., Lambertion reflection) are not necessarily needed. We propose to use a new measure, angle profile, to infer the hidden micro-structure from existing surfaces. In addition, the inferred results are further improved in the domain of discrete geometry processing (DGP) which is able to achieve a stable surface structure under a selectable enhancement setting. Extensive simulation results show that the proposed method obtains significantly improvements over uniform sharpening method in terms of both subjective visual assessment and objective quality metric.
RMPE: Regional Multi-Person Pose Estimation
Authors: Shuqin Xie, Yu-Wing Tai, Cewu Lu Hao-Shu Fang
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: Multi-person pose estimation in the wild is challenging. Although state-of-the-art human detectors have demonstrated good performance, small errors in localization and recognition are inevitable. These errors can cause failures for a single-person pose estimator (SPPE), especially for methods that solely depend on human detection results. In this paper, we propose a novel regional multi-person pose estimation (RMPE) framework to facilitate pose estimation in the presence of inaccurate human bounding boxes. Our framework consists of three components: Symmetric Spatial Transformer Network (SSTN), Parametric Pose Non-Maximum-Suppression (NMS), and Pose-Guided Proposals Generator (PGPG). Our method is able to handle inaccurate bounding boxes and redundant detections, allowing it to achieve 76.7 mAP on the MPII (multi person) dataset. Our model and source codes are made publicly available.
Online Video Object Detection Using Association LSTM
Authors: Cewu Lu, Chi-Keung Tang Yongyi Lu
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: Video object detection is a fundamental tool for many applications. Since direct application of image-based object detection cannot leverage the rich temporal information inherent in video data, we advocate to the detection of long-range video object pattern. While the Long Short-Term Memory (LSTM) has been the de facto choice for such detection, currently LSTM cannot fundamentally model object association between consecutive frames. In this paper, we propose the association LSTM to address this fundamental association problem. Association LSTM not only regresses and classifiy directly on object locations and categories but also associates features to represent each output object. By minimizing the matching error between these features, we learn how to associate objects in two consecutive frames. Additionally, our method works in an online manner, which is important for most video tasks. Compared to the traditional video object detection methods, our approach outperforms them on standard video datasets.
PolyFit: Polygonal Surface Reconstruction From Point Clouds
Authors: Peter Wonka Liangliang Nan
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: We propose a novel framework for reconstructing lightweight polygonal surfaces from point clouds. Unlike traditional methods that focus on either extracting good geometric primitives or obtaining proper arrangements of primitives, the emphasis of this work lies in intersecting the primitives (planes only) and seeking for an appropriate combination of them to obtain a manifold polygonal surface model without boundary. We show that reconstruction from point clouds can be cast as a binary labeling problem. Our method is based on a hypothesizing and selection strategy. We first generate a reasonably large set of face candidates by intersecting the extracted planar primitives. Then an optimal subset of the candidate faces is selected through optimization. Our optimization is based on a binary linear programming formulation under hard constraints that enforce the final polygonal surface model to be manifold and watertight. Experiments on point clouds from various sources demonstrate that our method can generate lightweight polygonal surface models of arbitrary piecewise planar objects. Besides, our method is capable of recovering sharp features and is robust to noise, outliers, and missing data.
Progressive Large Scale-Invariant Image Matching in Scale Space
Authors: Siyu Zhu, Tianwei Shen, Jinglu Wang, Tian Fang, Long Quan Lei Zhou
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: The power of modern image matching approaches is still fundamentally limited by the abrupt scale changes in images. In this paper, we propose a scale-invariant image matching approach to tackling the very large scale variation of views. Drawing inspiration from the scale space theory, we start with encoding the image's scale space into a compact multi-scale representation. Then, rather than trying to find the exact feature matches all in one step, we propose a progressive two-stage approach. First, we determine the related scale levels in scale space, enclosing the inlier feature correspondences, based on an optimal and exhaustive matching in a limited scale space. Second, we produce both the image similarity measurement and feature correspondences simultaneously after restricting matching between the related scale levels in a robust way. The matching performance has been intensively evaluated on vision tasks including image retrieval, feature matching and Structure-from-Motion (SfM). The successful integration of the challenging fusion of high aerial and low ground-level views with significant scale differences manifests the superiority of the proposed approach.
Efficient Global 2D-3D Matching for Camera Localization in a Large-Scale 3D Map
Authors: Hongdong Li, Yuchao Dai Liu Liu
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: Given an image of a street scene in a city, this paper develops a new method that can quickly and precisely pinpoint at which location (as well as viewing direction) the image was taken, against a pre-stored large-scale 3D point-cloud map of the city. We adopt the recently developed 2D-3D direct feature matching framework for this task [23,31,32,42-44]. This is a challenging task especially for large-scale problems. As the map size grows bigger, many 3D points in the wider geographical area can be visually very similar-or even identical-causing severe ambiguities in 2D-3D feature matching. The key is to quickly and unambiguously find the correct matches between a query image and the large 3D map. Existing methods solve this problem mainly via comparing individual features' visual similarities in a local and per feature manner, thus only local solutions can be found, inadequate for large-scale applications. In this paper, we introduce a global method which harnesses global contextual information exhibited both within the query image and among all the 3D points in the map. This is achieved by a novel global ranking algorithm, applied to a Markov network built upon the 3D map, which takes account of not only visual similarities between individual 2D-3D matches, but also their global compatibilities (as measured by co-visibility) among all matching pairs found in the scene. Tests on standard benchmark datasets show that our method achieved both higher precision and comparable recall, compared with the state-of-the-art.
Multi-View Non-Rigid Refinement and Normal Selection for High Quality 3D Reconstruction
Authors: Venu Madhav Govindu Sk. Mohammadul Haque
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: In recent years, there have been a variety of proposals for high quality 3D reconstruction by fusion of depth and normal maps that contain good low and high frequency information respectively. Typically, these methods create an initial mesh representation of the complete object or scene being scanned. Subsequently, normal estimates are assigned to each mesh vertex and a mesh-normal fusion step is carried out. In this paper, we present a complete pipeline for such depth-normal fusion. The key innovations in our pipeline are twofold. Firstly, we introduce a global multi-view non-rigid refinement step that corrects for the non-rigid misalignment present in the depth and normal maps. We demonstrate that such a correction is crucial for preserving fine-scale 3D features in the final reconstruction. Secondly, despite adequate care, the averaging of multiple normals invariably results in blurring of 3D detail. To mitigate this problem, we propose an approach that selects one out of many available normals. Our global cost for normal selection incorporates a variety of desirable properties and can be efficiently solved using graph cuts. We demonstrate the efficacy of our approach in generating high quality 3D reconstructions of both synthetic and real 3D models and compare with existing methods in the literature.
Multi-Stage Multi-Recursive-Input Fully Convolutional Networks for Neuronal Boundary Detection
Authors: Bin Wang, Yuan Jiang, Yan Wang, Alan Yuille Wei Shen
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: In the field of connectomics, neuroscientists seek to identify cortical connectivity comprehensively. Neuronal boundary detection from the Electron Microscopy (EM) images is often done to assist the automatic reconstruction of neuronal circuit. But the segmentation of EM images is a challenging problem, as it requires the detector to be able to detect both filament-like thin and blob-like thick membrane, while suppressing the ambiguous intracellular structure. In this paper, we propose multi-stage multi-recursiveinput fully convolutional networks to address this problem. The multiple recursive inputs for one stage, i.e., the multiple side outputs with different receptive field sizes learned from the lower stage, provide multi-scale contextual boundary information for the consecutive learning. This design is biologically-plausible, as it likes a human visual system to compare different possible segmentation solutions to address the ambiguous boundary issue. Our multi-stage networks are trained end-to-end. It achieves promising results on two public available EM segmentation datasets, the mouse piriform cortex dataset and the ISBI 2012 EM dataset.
Depth and Image Restoration From Light Field in a Scattering Medium
Authors: Zachary Murez, Tong Cui, Zhen Zhang, David Kriegman, Ravi Ramamoorthi Jiandong Tian
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: Traditional imaging methods and computer vision algorithms are often ineffective when images are acquired in scattering media, such as underwater, fog, and biological tissue. Here, we explore the use of light field imaging and algorithms for image restoration and depth estimation that address the image degradation from the medium. Towards this end, we make the following three contributions. First, we present a new single image restoration algorithm which removes backscatter and attenuation from images better than existing methods, and apply it to each view in the light field. Second, we combine a novel transmission based depth cue with existing correspondence and defocus cues to improve light field depth estimation. In densely scattering media, our transmission depth cue is critical for depth estimation since the images have low signal to noise ratios which significantly degrades the performance of the correspondence and defocus cues. Finally, we propose shearing and refocusing multiple views of the light field to recover a single image of higher quality than what is possible from a single view. We demonstrate the benefits of our method through extensive experimental results in a water tank.
Video Reflection Removal Through Spatio-Temporal Optimization
Authors: Mohamed Elgharib, Changil Kim, Mohamed Hefeeda, Wojciech Matusik Ajay Nandoriya
Published in: IEEE International Conference on Computer Vision (ICCV), 2017 (Main Conference Track), 2017

Abstract: Reflections can obstruct content during video capture and hence their removal is desirable. Current removal techniques are designed for still images, extracting only one reflection (foreground) and one background layer from the input. When extended to videos, unpleasant artifacts such as temporal flickering and incomplete separation are generated. We present a technique for video reflection removal by jointly solving for motion and separation. The novelty of our work is in our optimization formulation as well as the motion initialization strategy. We present a novel spatio-temporal optimization that takes n frames as input and directly estimates 2n frames as output, n for each layer. We aim to fully utilize spatio-temporal information in our objective terms. Our motion initialization is based on iterative frame-to-frame alignment instead of the direct alignment used by current approaches. We compare against advanced video extensions of the state of the art, and we significantly reduce temporal flickering and improve separation. In addition, we reduce image blur and recover moving objects more accurately. We validate our approach through subjective and objective evaluations on real and controlled data.