我们提出Segnext,这是一种简单的卷积网络体系结构,用于语义分割。由于自我注意力在编码空间信息中的效率,基于变压器的最新模型已主导语义分割领域。在本文中,我们表明卷积注意是一种比变形金刚中的自我注意机制更有效的编码上下文信息的方法。通过重新检查成功分割模型所拥有的特征,我们发现了几个关键组件,从而导致分割模型的性能提高。这促使我们设计了一个新型的卷积注意网络,该网络使用廉价的卷积操作。没有铃铛和哨子,我们的Segnext显着提高了先前最先进的方法对流行基准测试的性能,包括ADE20K,CityScapes,Coco-stuff,Pascal VOC,Pascal Context和ISAID。值得注意的是,segnext优于w/ nas-fpn的效率超过lavenet-l2,在帕斯卡VOC 2012测试排行榜上仅使用1/10参数,在Pascal VOC 2012测试排行榜上达到90.6%。平均而言,与具有相同或更少计算的ADE20K数据集上的最新方法相比,Segnext的改进约为2.0%。代码可在https://github.com/uyzhang/jseg(jittor)和https://github.com/visual-cratch-network/segnext(pytorch)获得。
translated by 谷歌翻译
虽然最初是为自然语言处理任务而设计的,但自我发挥的机制最近逐渐席卷了各种计算机视觉领域。但是,图像的2D性质带来了在计算机视觉中应用自我注意力的三个挑战。 (1)将图像作为1D序列忽略了其2D结构。 (2)对于高分辨率图像而言,二次复杂性太贵了。 (3)它仅捕获空间适应性,但忽略了通道适应性。在本文中,我们提出了一种新颖的线性注意力,名为“大核心注意”(LKA),以使自适应和远程相关性在自我注意力中避免其缺点。此外,我们提出了基于LKA的神经网络,即视觉注意力网络(VAN)。虽然非常简单,但范超过了相似的大小视觉变压器(VIT)和各种任务中的卷积神经网络(CNN),包括图像分类,对象检测,语义细分,泛型分割,姿势估计等。 ImageNet基准测试的精度为%,并为全景分割设置新的最先进性能(58.2 PQ)。此外,Van-B2超过Sw​​in-T 4%MIOU(50.1 vs. 46.1),用于ADE20K基准上的语义分割,2.6%AP(48.8 vs. 46.2)在COCO数据集上进行对象检测。它为社区提供了一种新颖的方法和简单而强大的基线。代码可从https://github.com/visual-crestention-network获得。
translated by 谷歌翻译
人类自然有效地在复杂的场景中找到突出区域。通过这种观察的动机,引入了计算机视觉中的注意力机制,目的是模仿人类视觉系统的这一方面。这种注意机制可以基于输入图像的特征被视为动态权重调整过程。注意机制在许多视觉任务中取得了巨大的成功,包括图像分类,对象检测,语义分割,视频理解,图像生成,3D视觉,多模态任务和自我监督的学习。在本调查中,我们对计算机愿景中的各种关注机制进行了全面的审查,并根据渠道注意,空间关注,暂时关注和分支注意力进行分类。相关的存储库https://github.com/menghaoguo/awesome-vision-tions致力于收集相关的工作。我们还建议了未来的注意机制研究方向。
translated by 谷歌翻译
作为现代深度学习的重要成分,关注机制,特别是自我关注,在全球相关发现中起着至关重要的作用。但是,在建模全局背景时,手工制作的注意力不可替代?我们的兴趣发现是自我关注并不优于20年前开发的矩阵分解(MD)模型,了解编码长距离依赖性的性能和计算成本。我们将全局上下文问题模拟为低级别恢复问题,并显示其优化算法可以帮助设计全局信息块。然后,本文提出了一系列汉堡包,其中我们采用了优化算法来解决MD,以将输入表示分解为子矩阵并重建低级别嵌入。具有不同MDS的汉堡包可以在小心地应对通过MDS的梯度时,对流行的全球背景模块自我关注进行。在愿景任务中进行综合实验,在那里学习全球范围至关重要,包括语义分割和图像生成,展示了对自我关注及其变体的显着改善。
translated by 谷歌翻译
卷积神经网络(CNNS)在2D计算机视觉中取得了很大的突破。然而,它们的不规则结构使得难以在网格上直接利用CNNS的潜力。细分表面提供分层多分辨率结构,其中闭合的2 - 歧管三角网格中的每个面正恰好邻近三个面。本文推出了这两种观察,介绍了具有环形细分序列连接的3D三角形网格的创新和多功能CNN框架。在2D图像中的网格面和像素之间进行类比允许我们呈现网状卷积操作者以聚合附近面的局部特征。通过利用面部街区,这种卷积可以支持标准的2D卷积网络概念,例如,可变内核大小,步幅和扩张。基于多分辨率层次结构,我们利用汇集层,将四个面均匀地合并成一个和上采样方法,该方法将一个面分为四个。因此,许多流行的2D CNN架构可以容易地适应处理3D网格。可以通过自我参数化来回收具有任意连接的网格,以使循环细分序列连接,使子变量是一般的方法。广泛的评估和各种应用展示了SubDIVNet的有效性和效率。
translated by 谷歌翻译
The irregular domain and lack of ordering make it challenging to design deep neural networks for point cloud processing. This paper presents a novel framework named Point Cloud Transformer(PCT) for point cloud learning. PCT is based on Transformer, which achieves huge success in natural language processing and displays great potential in image processing. It is inherently permutation invariant for processing a sequence of points, making it well-suited for point cloud learning. To better capture local context within the point cloud, we enhance input embedding with the support of farthest point sampling and nearest neighbor search. Extensive experiments demonstrate that the PCT achieves the state-of-the-art performance on shape classification, part segmentation, semantic segmentation and normal estimation tasks.
translated by 谷歌翻译
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.
translated by 谷歌翻译
It has been observed in practice that applying pruning-at-initialization methods to neural networks and training the sparsified networks can not only retain the testing performance of the original dense models, but also sometimes even slightly boost the generalization performance. Theoretical understanding for such experimental observations are yet to be developed. This work makes the first attempt to study how different pruning fractions affect the model's gradient descent dynamics and generalization. Specifically, this work considers a classification task for overparameterized two-layer neural networks, where the network is randomly pruned according to different rates at the initialization. It is shown that as long as the pruning fraction is below a certain threshold, gradient descent can drive the training loss toward zero and the network exhibits good generalization performance. More surprisingly, the generalization bound gets better as the pruning fraction gets larger. To complement this positive result, this work further shows a negative result: there exists a large pruning fraction such that while gradient descent is still able to drive the training loss toward zero (by memorizing noise), the generalization performance is no better than random guessing. This further suggests that pruning can change the feature learning process, which leads to the performance drop of the pruned neural network. Up to our knowledge, this is the \textbf{first} generalization result for pruned neural networks, suggesting that pruning can improve the neural network's generalization.
translated by 谷歌翻译
Time-series anomaly detection is an important task and has been widely applied in the industry. Since manual data annotation is expensive and inefficient, most applications adopt unsupervised anomaly detection methods, but the results are usually sub-optimal and unsatisfactory to end customers. Weak supervision is a promising paradigm for obtaining considerable labels in a low-cost way, which enables the customers to label data by writing heuristic rules rather than annotating each instance individually. However, in the time-series domain, it is hard for people to write reasonable labeling functions as the time-series data is numerically continuous and difficult to be understood. In this paper, we propose a Label-Efficient Interactive Time-Series Anomaly Detection (LEIAD) system, which enables a user to improve the results of unsupervised anomaly detection by performing only a small amount of interactions with the system. To achieve this goal, the system integrates weak supervision and active learning collaboratively while generating labeling functions automatically using only a few labeled data. All of these techniques are complementary and can promote each other in a reinforced manner. We conduct experiments on three time-series anomaly detection datasets, demonstrating that the proposed system is superior to existing solutions in both weak supervision and active learning areas. Also, the system has been tested in a real scenario in industry to show its practicality.
translated by 谷歌翻译
As an important variant of entity alignment (EA), multi-modal entity alignment (MMEA) aims to discover identical entities across different knowledge graphs (KGs) with multiple modalities like images. However, current MMEA algorithms all adopt KG-level modality fusion strategies but ignore modality differences among individual entities, hurting the robustness to potential noise involved in modalities (e.g., unidentifiable images and relations). In this paper we present MEAformer, a multi-modal entity alignment transformer approach for meta modality hybrid, to dynamically predict the mutual correlation coefficients among modalities for instance-level feature fusion. A modal-aware hard entity replay strategy is also proposed for addressing vague entity details. Extensive experimental results show that our model not only achieves SOTA performance on multiple training scenarios including supervised, unsupervised, iterative, and low resource, but also has limited parameters, optimistic speed, and good interpretability. Our code will be available soon.
translated by 谷歌翻译