神经网络的宽度很重要，因为增加了宽度，这必然会增加模型容量。但是，网络的性能不会随宽度而线性地提高，并且很快就会饱和。在这种情况下，我们认为，增加网络数量（合奏）的数量比纯粹增加宽度可以实现更好的准确性效率折衷。为了证明这一点，一个大型网络就其参数和正则化组件分为几个小网络。这些小型网络中的每一个都有原始参数的一小部分。然后，我们一起训练这些小型网络，使他们看到相同数据的各种观点，以增加它们的多样性。在此共同培训过程中，网络也可以相互学习。结果，小型网络可以比几乎没有或没有额外参数或拖船的大型网络获得更好的合奏性能，即实现更好的准确性效率折衷。通过并发运行，小型网络还可以比大型推理速度更快。以上所有内容都表明，网络的数量是模型缩放的新维度。我们通过广泛的实验在共同基准上使用8种不同的神经体系结构来验证我们的论点。该代码可在\ url {https://github.com/freeformrobotics/divide-and-co-training}中获得。

多EXIT体系结构由骨干和分支分类器组成，这些分类器提供缩短的推理途径，以减少深神经网络的运行时间。在本文中，我们分析了不同分支模式在分支分类器的计算复杂性分配方面有所不同。恒定复杂性分支使所有分支保持相同，同时复杂性增强和复杂性降低分支位置分别在骨架后期或更早的骨架上更复杂的分支。通过对多个骨干和数据集进行广泛的实验，我们发现复杂性削弱分支比恒定复杂性或复杂性增长分支更有效，这实现了最佳的准确性成本折衷。我们通过使用知识一致性来研究原因，以探测将分支添加到主链上的效果。我们的发现表明，复杂性降低的分支对骨干的特征抽象层次结构产生最小的破坏，这解释了分支模式的有效性。

由于存储器和计算资源有限，部署在移动设备上的卷积神经网络（CNNS）是困难的。我们的目标是通过利用特征图中的冗余来设计包括CPU和GPU的异构设备的高效神经网络，这很少在神经结构设计中进行了研究。对于类似CPU的设备，我们提出了一种新颖的CPU高效的Ghost（C-Ghost）模块，以生成从廉价操作的更多特征映射。基于一组内在的特征映射，我们使用廉价的成本应用一系列线性变换，以生成许多幽灵特征图，可以完全揭示内在特征的信息。所提出的C-Ghost模块可以作为即插即用组件，以升级现有的卷积神经网络。 C-Ghost瓶颈旨在堆叠C-Ghost模块，然后可以轻松建立轻量级的C-Ghostnet。我们进一步考虑GPU设备的有效网络。在建筑阶段的情况下，不涉及太多的GPU效率（例如，深度明智的卷积），我们建议利用阶段明智的特征冗余来制定GPU高效的幽灵（G-GHOST）阶段结构。舞台中的特征被分成两个部分，其中使用具有较少输出通道的原始块处理第一部分，用于生成内在特征，另一个通过利用阶段明智的冗余来生成廉价的操作。在基准测试上进行的实验证明了所提出的C-Ghost模块和G-Ghost阶段的有效性。 C-Ghostnet和G-Ghostnet分别可以分别实现CPU和GPU的准确性和延迟的最佳权衡。代码可在https://github.com/huawei-noah/cv-backbones获得。

大多数现有的深神经网络都是静态的，这意味着它们只能以固定的复杂性推断。但资源预算可以大幅度不同。即使在一个设备上，实惠预算也可以用不同的场景改变，并且对每个所需预算的反复培训网络是非常昂贵的。因此，在这项工作中，我们提出了一种称为Mutualnet的一般方法，以训练可以以各种资源约束运行的单个网络。我们的方法列举了具有各种网络宽度和输入分辨率的模型配置队列。这种相互学习方案不仅允许模型以不同的宽度分辨率配置运行，而且还可以在这些配置之间传输独特的知识，帮助模型来学习更强大的表示。 Mutualnet是一般的培训方法，可以应用于各种网络结构（例如，2D网络：MobileNets，Reset，3D网络：速度，X3D）和各种任务（例如，图像分类，对象检测，分段和动作识别），并证明了实现各种数据集的一致性改进。由于我们只培训了这一模型，它对独立培训多种型号而言，它也大大降低了培训成本。令人惊讶的是，如果动态资源约束不是一个问题，则可以使用Mutualnet来显着提高单个网络的性能。总之，Mutualnet是静态和自适应，2D和3D网络的统一方法。代码和预先训练的模型可用于\ url {https://github.com/tayang1122/mutualnet}。

Deploying convolutional neural networks (CNNs) on embedded devices is difficult due to the limited memory and computation resources. The redundancy in feature maps is an important characteristic of those successful CNNs, but has rarely been investigated in neural architecture design. This paper proposes a novel Ghost module to generate more feature maps from cheap operations. Based on a set of intrinsic feature maps, we apply a series of linear transformations with cheap cost to generate many ghost feature maps that could fully reveal information underlying intrinsic features. The proposed Ghost module can be taken as a plug-and-play component to upgrade existing convolutional neural networks. Ghost bottlenecks are designed to stack Ghost modules, and then the lightweight Ghost-Net can be easily established. Experiments conducted on benchmarks demonstrate that the proposed Ghost module is an impressive alternative of convolution layers in baseline models, and our GhostNet can achieve higher recognition performance (e.g. 75.7% top-1 accuracy) than MobileNetV3 with similar computational cost on the ImageNet ILSVRC-2012 classification dataset. Code is available at https: //github.com/huawei-noah/ghostnet.

Deep residual networks were shown to be able to scale up to thousands of layers and still have improving performance. However, each fraction of a percent of improved accuracy costs nearly doubling the number of layers, and so training very deep residual networks has a problem of diminishing feature reuse, which makes these networks very slow to train. To tackle these problems, in this paper we conduct a detailed experimental study on the architecture of ResNet blocks, based on which we propose a novel architecture where we decrease depth and increase width of residual networks. We call the resulting network structures wide residual networks (WRNs) and show that these are far superior over their commonly used thin and very deep counterparts. For example, we demonstrate that even a simple 16-layer-deep wide residual network outperforms in accuracy and efficiency all previous deep residual networks, including thousand-layerdeep networks, achieving new state-of-the-art results on CIFAR, SVHN, COCO, and significant improvements on ImageNet. Our code and models are available at https: //github.com/szagoruyko/wide-residual-networks.

We present a simple, highly modularized network architecture for image classification. Our network is constructed by repeating a building block that aggregates a set of transformations with the same topology. Our simple design results in a homogeneous, multi-branch architecture that has only a few hyper-parameters to set. This strategy exposes a new dimension, which we call "cardinality" (the size of the set of transformations), as an essential factor in addition to the dimensions of depth and width. On the ImageNet-1K dataset, we empirically show that even under the restricted condition of maintaining complexity, increasing cardinality is able to improve classification accuracy. Moreover, increasing cardinality is more effective than going deeper or wider when we increase the capacity. Our models, named ResNeXt, are the foundations of our entry to the ILSVRC 2016 classification task in which we secured 2nd place. We further investigate ResNeXt on an ImageNet-5K set and the COCO detection set, also showing better results than its ResNet counterpart. The code and models are publicly available online 1 .

We introduce an extremely computation-efficient CNN architecture named ShuffleNet, which is designed specially for mobile devices with very limited computing power (e.g., 10-150 MFLOPs). The new architecture utilizes two new operations, pointwise group convolution and channel shuffle, to greatly reduce computation cost while maintaining accuracy. Experiments on ImageNet classification and MS COCO object detection demonstrate the superior performance of ShuffleNet over other structures, e.g. lower top-1 error (absolute 7.8%) than recent MobileNet [12] on Ima-geNet classification task, under the computation budget of 40 MFLOPs. On an ARM-based mobile device, ShuffleNet achieves ∼13× actual speedup over AlexNet while maintaining comparable accuracy.

深度学习技术在各种任务中都表现出了出色的有效性，并且深度学习具有推进多种应用程序（包括在边缘计算中）的潜力，其中将深层模型部署在边缘设备上，以实现即时的数据处理和响应。一个关键的挑战是，虽然深层模型的应用通常会产生大量的内存和计算成本，但Edge设备通常只提供非常有限的存储和计算功能，这些功能可能会在各个设备之间差异很大。这些特征使得难以构建深度学习解决方案，以释放边缘设备的潜力，同时遵守其约束。应对这一挑战的一种有希望的方法是自动化有效的深度学习模型的设计，这些模型轻巧，仅需少量存储，并且仅产生低计算开销。该调查提供了针对边缘计算的深度学习模型设计自动化技术的全面覆盖。它提供了关键指标的概述和比较，这些指标通常用于量化模型在有效性，轻度和计算成本方面的水平。然后，该调查涵盖了深层设计自动化技术的三类最新技术：自动化神经体系结构搜索，自动化模型压缩以及联合自动化设计和压缩。最后，调查涵盖了未来研究的开放问题和方向。

Much of the recent progress made in image classification research can be credited to training procedure refinements, such as changes in data augmentations and optimization methods. In the literature, however, most refinements are either briefly mentioned as implementation details or only visible in source code. In this paper, we will examine a collection of such refinements and empirically evaluate their impact on the final model accuracy through ablation study. We will show that, by combining these refinements together, we are able to improve various CNN models significantly. For example, we raise ResNet-50's top-1 validation accuracy from 75.3% to 79.29% on ImageNet. We will also demonstrate that improvement on image classification accuracy leads to better transfer learning performance in other application domains such as object detection and semantic segmentation.

This paper introduces EfficientNetV2, a new family of convolutional networks that have faster training speed and better parameter efficiency than previous models. To develop these models, we use a combination of training-aware neural architecture search and scaling, to jointly optimize training speed and parameter efficiency. The models were searched from the search space enriched with new ops such as Fused-MBConv. Our experiments show that EfficientNetV2 models train much faster than state-of-the-art models while being up to 6.8x smaller.Our training can be further sped up by progressively increasing the image size during training, but it often causes a drop in accuracy. To compensate for this accuracy drop, we propose an improved method of progressive learning, which adaptively adjusts regularization (e.g. data augmentation) along with image size.With progressive learning, our EfficientNetV2 significantly outperforms previous models on Im-ageNet and CIFAR/Cars/Flowers datasets. By pretraining on the same ImageNet21k, our Effi-cientNetV2 achieves 87.3% top-1 accuracy on ImageNet ILSVRC2012, outperforming the recent ViT by 2.0% accuracy while training 5x-11x faster using the same computing resources. Code is available at https://github.com/google/ automl/tree/master/efficientnetv2.

在每个卷积层中学习一个静态卷积内核是现代卷积神经网络（CNN）的常见训练范式。取而代之的是，动态卷积的最新研究表明，学习$ n $卷积核与输入依赖性注意的线性组合可以显着提高轻重量CNN的准确性，同时保持有效的推断。但是，我们观察到现有的作品endow卷积内核具有通过一个维度（关于卷积内核编号）的动态属性（关于内核空间的卷积内核编号），但其他三个维度（关于空间大小，输入通道号和输出通道编号和输出通道号，每个卷积内核）被忽略。受到这一点的启发，我们提出了Omni维动态卷积（ODCONV），这是一种更普遍而优雅的动态卷积设计，以推进这一研究。 ODCONV利用了一种新型的多维注意机制，采用平行策略来学习沿着任何卷积层的内核空间的所有四个维度学习卷积内核的互补关注。作为定期卷积的倒数替换，可以将ODCONV插入许多CNN架构中。 ImageNet和MS-Coco数据集的广泛实验表明，ODCONV为包括轻量重量和大型的各种盛行的CNN主链带来了可靠的准确性提升，例如3.77％〜5.71％| 1.86％〜3.72％〜3.72％的绝对1个绝对1改进至ImabivLenetV2 | ImageNet数据集上的重新连接家族。有趣的是，由于其功能学习能力的提高，即使具有一个单个内核的ODCONV也可以与具有多个内核的现有动态卷积对应物竞争或超越现有的动态卷积对应物，从而大大降低了额外的参数。此外，ODCONV也优于其他注意模块，用于调节输出特征或卷积重量。

Light-weight convolutional neural networks (CNNs) suffer performance degradation as their low computational budgets constrain both the depth (number of convolution layers) and the width (number of channels) of CNNs, resulting in limited representation capability. To address this issue, we present Dynamic Convolution, a new design that increases model complexity without increasing the network depth or width. Instead of using a single convolution kernel per layer, dynamic convolution aggregates multiple parallel convolution kernels dynamically based upon their attentions, which are input dependent. Assembling multiple kernels is not only computationally efficient due to the small kernel size, but also has more representation power since these kernels are aggregated in a non-linear way via attention. By simply using dynamic convolution for the state-ofthe-art architecture MobileNetV3-Small, the top-1 accuracy of ImageNet classification is boosted by 2.9% with only 4% additional FLOPs and 2.9 AP gain is achieved on COCO keypoint detection.

Recent work has shown that convolutional networks can be substantially deeper, more accurate, and efficient to train if they contain shorter connections between layers close to the input and those close to the output. In this paper, we embrace this observation and introduce the Dense Convolutional Network (DenseNet), which connects each layer to every other layer in a feed-forward fashion. Whereas traditional convolutional networks with L layers have L connections-one between each layer and its subsequent layer-our network has L(L+1) 2 direct connections. For each layer, the feature-maps of all preceding layers are used as inputs, and its own feature-maps are used as inputs into all subsequent layers. DenseNets have several compelling advantages: they alleviate the vanishing-gradient problem, strengthen feature propagation, encourage feature reuse, and substantially reduce the number of parameters. We evaluate our proposed architecture on four highly competitive object recognition benchmark tasks SVHN, and ImageNet). DenseNets obtain significant improvements over the state-of-the-art on most of them, whilst requiring less computation to achieve high performance. Code and pre-trained models are available at https://github.com/liuzhuang13/DenseNet.

多年来，Yolo系列一直是有效对象检测的事实上的行业级别标准。尤洛社区（Yolo Community）绝大多数繁荣，以丰富其在众多硬件平台和丰富场景中的使用。在这份技术报告中，我们努力将其限制推向新的水平，以坚定不移的行业应用心态前进。考虑到对真实环境中速度和准确性的多种要求，我们广泛研究了行业或学术界的最新对象检测进步。具体而言，我们从最近的网络设计，培训策略，测试技术，量化和优化方法中大量吸收了思想。最重要的是，我们整合了思想和实践，以在各种规模上建立一套可供部署的网络，以适应多元化的用例。在Yolo作者的慷慨许可下，我们将其命名为Yolov6。我们还向用户和贡献者表示热烈欢迎，以进一步增强。为了了解性能，我们的Yolov6-N在NVIDIA TESLA T4 GPU上以1234 fps的吞吐量在可可数据集上击中35.9％的AP。 Yolov6-S在495 fps处的43.5％AP罢工，在相同规模〜（Yolov5-S，Yolox-S和Ppyoloe-S）上超过其他主流探测器。我们的量化版本的Yolov6-S甚至在869 fps中带来了新的43.3％AP。此外，与其他推理速度相似的检测器相比，Yolov6-m/L的精度性能（即49.5％/52.3％）更好。我们仔细进行了实验以验证每个组件的有效性。我们的代码可在https://github.com/meituan/yolov6上提供。

我们提出了一种多移民通道（MGIC）方法，该方法可以解决参数数量相对于标准卷积神经网络（CNN）中的通道数的二次增长。因此，我们的方法解决了CNN中的冗余，这也被轻量级CNN的成功所揭示。轻巧的CNN可以达到与参数较少的标准CNN的可比精度。但是，权重的数量仍然随CNN的宽度四倍地缩放。我们的MGIC体系结构用MGIC对应物代替了每个CNN块，该块利用了小组大小的嵌套分组卷积的层次结构来解决此问题。因此，我们提出的架构相对于网络的宽度线性扩展，同时保留了通道的完整耦合，如标准CNN中。我们对图像分类，分割和点云分类进行的广泛实验表明，将此策略应用于Resnet和MobilenetV3等不同体系结构，可以减少参数的数量，同时获得相似或更好的准确性。

在本文中，我们通过利用视觉数据中的空间稀疏性提出了一种新的模型加速方法。我们观察到，视觉变压器中的最终预测仅基于最有用的令牌的子集，这足以使图像识别。基于此观察，我们提出了一个动态的令牌稀疏框架，以根据加速视觉变压器的输入逐渐和动态地修剪冗余令牌。具体而言，我们设计了一个轻量级预测模块，以估计给定当前功能的每个令牌的重要性得分。该模块被添加到不同的层中以层次修剪冗余令牌。尽管该框架的启发是我们观察到视觉变压器中稀疏注意力的启发，但我们发现自适应和不对称计算的想法可能是加速各种体系结构的一般解决方案。我们将我们的方法扩展到包括CNN和分层视觉变压器在内的层次模型，以及更复杂的密集预测任务，这些任务需要通过制定更通用的动态空间稀疏框架，并具有渐进性的稀疏性和非对称性计算，用于不同空间位置。通过将轻质快速路径应用于少量的特征，并使用更具表现力的慢速路径到更重要的位置，我们可以维护特征地图的结构，同时大大减少整体计算。广泛的实验证明了我们框架对各种现代体系结构和不同视觉识别任务的有效性。我们的结果清楚地表明，动态空间稀疏为模型加速提供了一个新的，更有效的维度。代码可从https://github.com/raoyongming/dynamicvit获得

深度卷积神经网络（CNNS）通常是复杂的设计，具有许多可学习的参数，用于准确性原因。为了缓解在移动设备上部署它们的昂贵成本，最近的作品使挖掘预定识别架构中的冗余作出了巨大努力。然而，尚未完全研究现代CNN的输入分辨率的冗余，即输入图像的分辨率是固定的。在本文中，我们观察到，用于准确预测给定图像的最小分辨率使用相同的神经网络是不同的。为此，我们提出了一种新颖的动态分辨率网络（DRNET），其中基于每个输入样本动态地确定输入分辨率。其中，利用所需网络共同地探索具有可忽略的计算成本的分辨率预测器。具体地，预测器学习可以保留的最小分辨率，并且甚至超过每个图像的原始识别准确性。在推断过程中，每个输入图像将被调整为其预测的分辨率，以最小化整体计算负担。然后，我们对几个基准网络和数据集进行了广泛的实验。结果表明，我们的DRNET可以嵌入到任何现成的网络架构中，以获得计算复杂性的相当大降低。例如，DR-RESET-50实现了类似的性能，计算减少约34％，同时增加了1.4％的准确度，与原始Resnet-50上的计算减少相比，在ImageNet上的原始resnet-50增加了10％。

Representing features at multiple scales is of great importance for numerous vision tasks. Recent advances in backbone convolutional neural networks (CNNs) continually demonstrate stronger multi-scale representation ability, leading to consistent performance gains on a wide range of applications. However, most existing methods represent the multi-scale features in a layerwise manner. In this paper, we propose a novel building block for CNNs, namely Res2Net, by constructing hierarchical residual-like connections within one single residual block. The Res2Net represents multi-scale features at a granular level and increases the range of receptive fields for each network layer. The proposed Res2Net block can be plugged into the state-of-the-art backbone CNN models, e.g., ResNet, ResNeXt, and DLA. We evaluate the Res2Net block on all these models and demonstrate consistent performance gains over baseline models on widely-used datasets, e.g., CIFAR-100 and ImageNet. Further ablation studies and experimental results on representative computer vision tasks, i.e., object detection, class activation mapping, and salient object detection, further verify the superiority of the Res2Net over the state-of-the-art baseline methods. The source code and trained models are available on https://mmcheng.net/res2net/.

更好的准确性和效率权衡在对象检测中是一个具有挑战性的问题。在这项工作中，我们致力于研究对象检测的关键优化和神经网络架构选择，以提高准确性和效率。我们调查了无锚策略对轻质对象检测模型的适用性。我们增强了骨干结构并设计了颈部的轻质结构，从而提高了网络的特征提取能力。我们改善标签分配策略和损失功能，使培训更稳定和高效。通过这些优化，我们创建了一个名为PP-Picodet的新的实时对象探测器系列，这在移动设备的对象检测上实现了卓越的性能。与其他流行型号相比，我们的模型在准确性和延迟之间实现了更好的权衡。 Picodet-s只有0.99m的参数达到30.6％的地图，它是地图的绝对4.8％，同时与yolox-nano相比将移动CPU推理延迟减少55％，并且与Nanodet相比，MAP的绝对改善了7.1％。当输入大小为320时，它在移动臂CPU上达到123个FPS（使用桨Lite）。Picodet-L只有3.3M参数，达到40.9％的地图，这是地图的绝对3.7％，比yolov5s更快44％ 。如图1所示，我们的模型远远优于轻量级对象检测的最先进的结果。代码和预先训练的型号可在https://github.com/paddlepaddle/paddledentions提供。