神经表面重建旨在基于多视图图像重建准确的3D表面。基于神经量的先前方法主要训练完全隐式的模型，它们需要单个场景的数小时培训。最近的努力探讨了明确的体积表示，该表示通过记住可学习的素网格中的重要信息，从而大大加快了优化过程。但是，这些基于体素的方法通常在重建细粒几何形状方面遇到困难。通过实证研究，我们发现高质量的表面重建取决于两个关键因素：构建相干形状的能力和颜色几何依赖性的精确建模。特别是，后者是准确重建细节的关键。受这些发现的启发，我们开发了Voxurf，这是一种基于体素的方法，用于有效，准确的神经表面重建，该方法由两个阶段组成：1）利用可学习的特征网格来构建颜色场并获得连贯的粗糙形状，并且2）使用双色网络来完善详细的几何形状，可捕获精确的颜色几何依赖性。我们进一步引入了层次几何特征，以启用跨体素的信息共享。我们的实验表明，Voxurf同时达到了高效率和高质量。在DTU基准测试中，与最先进的方法相比，Voxurf获得了更高的重建质量，训练的加速度为20倍。

2D图像是对用几何形状，材料和照明组件描绘的3D物理世界的观察。从2D图像（也称为逆渲染）中恢复这些基本的内在组件通常需要有监督的设置，并从多个观点和照明条件中收集的配对图像，这是资源要求的。在这项工作中，我们提出了GAN2X，这是一种无监督的逆渲染方法，仅使用未配对的图像进行训练。与以前主要集中在3D形状的形状 - 从GAN的方法不同，我们首次尝试通过利用GAN生成的伪配对数据来恢复非陆层材料的性能。为了实现精确的逆渲染，我们设计了一种镜面感知的神经表面表示，该表示连续建模几何和材料特性。采用基于阴影的改进技术来进一步提炼目标图像中的信息并恢复更多细节。实验表明，GAN2X可以准确地将2D图像分解为不同对象类别的3D形状，反照率和镜面特性，并实现无监督的单视图3D面部重建的最先进性能。我们还显示了其在下游任务中的应用，包括真实的图像编辑和将2D GAN抬高到分解3D GAN。

神经辐射场（NERF）在建模3D对象和受控场景中取得了出色的性能，通常在单一的范围内。在这项工作中，我们首次尝试将NERF带到城市规模，观点包括卫星级，旨在捕获一个城市的概览，到地面图像，显示架构的复杂细节。到现场的相机距离的广泛跨度产生了具有不同细节水平和空间覆盖率的多尺度数据，这对Vanilla Nerf产生了极大的挑战，并将其偏向于受损结果。为了解决这些问题，我们介绍了CitynerF，这是一个渐进式学习范例，可以同步地增长NERF模型和训练。从拟合浅景层的遥远的视图开始，随着训练的进展，附加新的块以在越来越近的视图中适应新兴细节。该策略有效地激活了位置编码中的高频信道，并将更复杂的细节展开，因为训练进行了。我们展示了CitalnerF在模拟各种城市规模场景中的优越性，具有巨大的不同视图，以及在不同级别的细节中渲染视图的支持。

生成辐射田地的出现显着促进了3D感知图像合成的发展。辐射字段中的累积渲染过程使得这些生成模型更容易，因为渐变在整个音量上分布，但导致扩散的物体表面。与此同时，与Radiance Fields相比，占用表示可以本质地确保确定性表面。但是，如果我们直接向生成模型应用占用表示，在培训期间，它们只会在物体表面上接收稀疏梯度，并最终遭受收敛问题。在本文中，我们提出了一种基于生成的辐射场的新型模型的生成占用场（GOF），这些模型可以在不妨碍其训练收敛的情况下学习紧凑的物体表面。 GOF的关键介绍是从辐射字段中累积渲染到渲染的专用过渡，只有在学习的表面越来越准确的情况下，只有曲面点渲染。通过这种方式，GOF将两个表示的优点组合在统一的框架中。在实践中，通过逐渐将采样区域从整个体积逐渐缩小到表面周围的最小相邻区域，在GOF中实现了从辐射场和3月到占用表示的训练时间转换。通过对多个数据集的全面实验，我们证明了GOF可以合成具有3D一致性的高质量图像，并同时学习紧凑且光滑的物体表面。代码，模型和演示视频可在https://shedontsui.g​​ithub.io/projects/gof中获得

生成辐射场的进步推动了3D感知图像合成的边界。通过观察到3D对象应该从多个观点看起来真实的观察，这些方法将多视图约束引入正则化以从2D图像学习有效的3D辐射场。尽管有了进步，但由于形状彩色模糊，它们通常会缺少准确的3D形状，这限制了它们在下游任务中的适用性。在这项工作中，我们通过提出一种新的阴影引导的生成隐式模型来解决这种模糊性，能够学习持续改进的形状表示。我们的主要洞察力是，在不同的照明条件下，精确的3D形状还应产生逼真的渲染。通过明确地模拟照明和具有各种照明条件的阴影来实现这种多照明约束。通过将合成的图像馈送到鉴别器来导出梯度。为了补偿计算表面法线的额外计算负担，我们进一步通过表面跟踪设计了高效的体积渲染策略，将培训和推理时间分别将培训和推理时间减少了24％和48％。我们在多个数据集上的实验表明，该方法在捕获准确的基础3D形状时实现了光电型3D感知图像合成。我们展示了我们对现有方法的3D形重建的方法的改进性能，并展示了其对图像复兴的适用性。我们的代码将在https://github.com/xingangpan/shadegan发布。

Learning a good image prior is a long-term goal for image restoration and manipulation. While existing methods like deep image prior (DIP) capture low-level image statistics, there are still gaps toward an image prior that captures rich image semantics including color, spatial coherence, textures, and high-level concepts. This work presents an effective way to exploit the image prior captured by a generative adversarial network (GAN) trained on large-scale natural images. As shown in Fig. 1, the deep generative prior (DGP) provides compelling results to restore missing semantics, e.g., color, patch, resolution, of various degraded images. It also enables diverse image manipulation including random jittering, image morphing, and category transfer. Such highly flexible restoration and manipulation are made possible through relaxing the assumption of existing GAN-inversion methods, which tend to fix the generator. Notably, we allow the generator to be fine-tuned on-the-fly in a progressive manner regularized by feature distance obtained by the discriminator in GAN. We show that these easy-to-implement and practical changes help preserve the reconstruction to remain in the manifold of nature image, and thus lead to more precise and faithful reconstruction for real images. Code is available at https://github.com/XingangPan/deepgenerative-prior.

Convolutional neural networks (CNNs) have achieved great successes in many computer vision problems. Unlike existing works that designed CNN architectures to improve performance on a single task of a single domain and not generalizable, we present IBN-Net, a novel convolutional architecture, which remarkably enhances a CNN's modeling ability on one domain (e.g. Cityscapes) as well as its generalization capacity on another domain (e.g. GTA5) without finetuning. IBN-Net carefully integrates Instance Normalization (IN) and Batch Normalization (BN) as building blocks, and can be wrapped into many advanced deep networks to improve their performances. This work has three key contributions. (1) By delving into IN and BN, we disclose that IN learns features that are invariant to appearance changes, such as colors, styles, and virtuality/reality, while BN is essential for preserving content related information. (2) IBN-Net can be applied to many advanced deep architectures, such as DenseNet, ResNet, ResNeXt, and SENet, and consistently improve their performance without increasing computational cost. 1 (3) When applying the trained networks to new domains, e.g. from GTA5 to Cityscapes, IBN-Net achieves comparable improvements as domain adaptation methods, even without using data from the target domain. With IBN-Net, we won the 1st place on the WAD 2018 Challenge Drivable Area track, with an mIoU of 86.18%.

Blind image quality assessment (BIQA) remains challenging due to the diversity of distortion and image content variation, which complicate the distortion patterns crossing different scales and aggravate the difficulty of the regression problem for BIQA. However, existing BIQA methods often fail to consider multi-scale distortion patterns and image content, and little research has been done on learning strategies to make the regression model produce better performance. In this paper, we propose a simple yet effective Progressive Multi-Task Image Quality Assessment (PMT-IQA) model, which contains a multi-scale feature extraction module (MS) and a progressive multi-task learning module (PMT), to help the model learn complex distortion patterns and better optimize the regression issue to align with the law of human learning process from easy to hard. To verify the effectiveness of the proposed PMT-IQA model, we conduct experiments on four widely used public datasets, and the experimental results indicate that the performance of PMT-IQA is superior to the comparison approaches, and both MS and PMT modules improve the model's performance.

In this paper, we study the problem of knowledge-intensive text-to-SQL, in which domain knowledge is necessary to parse expert questions into SQL queries over domain-specific tables. We formalize this scenario by building a new Chinese benchmark KnowSQL consisting of domain-specific questions covering various domains. We then address this problem by presenting formulaic knowledge, rather than by annotating additional data examples. More concretely, we construct a formulaic knowledge bank as a domain knowledge base and propose a framework (ReGrouP) to leverage this formulaic knowledge during parsing. Experiments using ReGrouP demonstrate a significant 28.2% improvement overall on KnowSQL.

Temporal sentence grounding (TSG) aims to identify the temporal boundary of a specific segment from an untrimmed video by a sentence query. All existing works first utilize a sparse sampling strategy to extract a fixed number of video frames and then conduct multi-modal interactions with query sentence for reasoning. However, we argue that these methods have overlooked two indispensable issues: 1) Boundary-bias: The annotated target segment generally refers to two specific frames as corresponding start and end timestamps. The video downsampling process may lose these two frames and take the adjacent irrelevant frames as new boundaries. 2) Reasoning-bias: Such incorrect new boundary frames also lead to the reasoning bias during frame-query interaction, reducing the generalization ability of model. To alleviate above limitations, in this paper, we propose a novel Siamese Sampling and Reasoning Network (SSRN) for TSG, which introduces a siamese sampling mechanism to generate additional contextual frames to enrich and refine the new boundaries. Specifically, a reasoning strategy is developed to learn the inter-relationship among these frames and generate soft labels on boundaries for more accurate frame-query reasoning. Such mechanism is also able to supplement the absent consecutive visual semantics to the sampled sparse frames for fine-grained activity understanding. Extensive experiments demonstrate the effectiveness of SSRN on three challenging datasets.