由于具有强大的功能学习能力和高效率,深层哈希在大规模图像检索中取得了巨大的成功。同时,广泛的作品表明,深层神经网络(DNN)容易受到对抗例子的影响,并且探索针对深哈希的对抗性攻击吸引了许多研究工作。然而,尚未对Backdoor攻击(对DNNS的另一个著名威胁)进行深入研究。尽管图像分类领域已经提出了各种后门攻击,但现有方法未能实现真正的不可思议的后门攻击,该攻击享受着隐形触发器并同时享受清洁标签设置,而且它们也无法满足图像检索后门的内在需求。在本文中,我们提出了Badhash,这是第一个基于生成的无透感的后门攻击,对深哈希的攻击,它可以有效地用干净的标签产生隐形和投入特定的中毒图像。具体而言,我们首先提出了一种新的条件生成对抗网络(CGAN)管道,以有效生成中毒样品。对于任何给定的良性图像,它试图产生具有独特无形扳机的自然中毒对应物。为了提高攻击效果,我们引入了基于标签的对比学习网络LabCln来利用不同标签的语义特征,随后将其用于混淆和误导目标模型以学习嵌入式触发器。我们终于探索了在哈希空间中对图像检索的后门攻击的机制。在多个基准数据集上进行的广泛实验证明,Badhash可以生成不察觉的中毒样本,具有强大的攻击能力和对最新的深层哈希方案的可转移性。主要主题领域:[参与]多媒体搜索和建议
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多尺度特征的学习和聚集对于授权神经网络以捕获点云上采样任务中的细颗粒几何细节至关重要。大多数现有方法从固定分辨率的点云中提取多尺度功能,因此仅获得有限的细节。尽管现有的方法汇总了一系列Upplampling子网络的不同分辨率的特征层次结构,但培训既复杂又具有昂贵的计算。为了解决这些问题,我们构建了一个名为BIMS-PU的新点云上采样管道,该管道将特征金字塔体系结构与双向上下采样路径集成在一起。具体而言,我们通过将目标采样因子分解为较小的因素,将上/下采样过程分解为几个上/下采​​样子步骤。多尺度特征是自然而然地以平行方式生产的,并使用快速特征融合方法进行聚合。监督信号同时应用于不同尺度的所有上采样点云。此外,我们制定一个残留块,以减轻模型的训练。不同数据集上的广泛定量和定性实验表明,我们的方法取得了优于最先进方法的结果。最后但并非最不重要的一点是,我们证明了点云上采样可以通过改善3D数据质量来改善机器人感知。
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利用多尺度功能在解决语义细分问题方面表现出了巨大的潜力。聚集通常是用总和或串联(Concat)进行的,然后是卷积(Conv)层。但是,它将高级上下文完全通过了以下层次结构,而无需考虑它们的相互关系。在这项工作中,我们旨在启用低级功能,以通过跨尺度像素到区域关系操作从相邻的高级特征图中汇总互补上下文。我们利用跨尺度上下文的传播,即使高分辨率的低级特征也可以使远程依赖关系也可以捕获。为此,我们采用有效的功能金字塔网络来获得多尺度功能。我们提出了一个关系语义提取器(RSE)和关系语义传播器(RSP),分别用于上下文提取和传播。然后,我们将几个RSP堆叠到RSP头中,以实现上下文的渐进自上而下分布。两个具有挑战性的数据集和可可的实验结果表明,RSP头在语义细分和泛型分割方面都具有高效率的竞争性。在语义分割任务中,它的表现优于DeepLabv3 [1],而在语义分割任务中少75%(多重添加)。
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Masked image modeling (MIM) performs strongly in pre-training large vision Transformers (ViTs). However, small models that are critical for real-world applications cannot or only marginally benefit from this pre-training approach. In this paper, we explore distillation techniques to transfer the success of large MIM-based pre-trained models to smaller ones. We systematically study different options in the distillation framework, including distilling targets, losses, input, network regularization, sequential distillation, etc, revealing that: 1) Distilling token relations is more effective than CLS token- and feature-based distillation; 2) An intermediate layer of the teacher network as target perform better than that using the last layer when the depth of the student mismatches that of the teacher; 3) Weak regularization is preferred; etc. With these findings, we achieve significant fine-tuning accuracy improvements over the scratch MIM pre-training on ImageNet-1K classification, using all the ViT-Tiny, ViT-Small, and ViT-base models, with +4.2%/+2.4%/+1.4% gains, respectively. Our TinyMIM model of base size achieves 52.2 mIoU in AE20K semantic segmentation, which is +4.1 higher than the MAE baseline. Our TinyMIM model of tiny size achieves 79.6% top-1 accuracy on ImageNet-1K image classification, which sets a new record for small vision models of the same size and computation budget. This strong performance suggests an alternative way for developing small vision Transformer models, that is, by exploring better training methods rather than introducing inductive biases into architectures as in most previous works. Code is available at https://github.com/OliverRensu/TinyMIM.
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In this paper, we propose a robust 3D detector, named Cross Modal Transformer (CMT), for end-to-end 3D multi-modal detection. Without explicit view transformation, CMT takes the image and point clouds tokens as inputs and directly outputs accurate 3D bounding boxes. The spatial alignment of multi-modal tokens is performed implicitly, by encoding the 3D points into multi-modal features. The core design of CMT is quite simple while its performance is impressive. CMT obtains 73.0% NDS on nuScenes benchmark. Moreover, CMT has a strong robustness even if the LiDAR is missing. Code will be released at https://github.com/junjie18/CMT.
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Dataset distillation has emerged as a prominent technique to improve data efficiency when training machine learning models. It encapsulates the knowledge from a large dataset into a smaller synthetic dataset. A model trained on this smaller distilled dataset can attain comparable performance to a model trained on the original training dataset. However, the existing dataset distillation techniques mainly aim at achieving the best trade-off between resource usage efficiency and model utility. The security risks stemming from them have not been explored. This study performs the first backdoor attack against the models trained on the data distilled by dataset distillation models in the image domain. Concretely, we inject triggers into the synthetic data during the distillation procedure rather than during the model training stage, where all previous attacks are performed. We propose two types of backdoor attacks, namely NAIVEATTACK and DOORPING. NAIVEATTACK simply adds triggers to the raw data at the initial distillation phase, while DOORPING iteratively updates the triggers during the entire distillation procedure. We conduct extensive evaluations on multiple datasets, architectures, and dataset distillation techniques. Empirical evaluation shows that NAIVEATTACK achieves decent attack success rate (ASR) scores in some cases, while DOORPING reaches higher ASR scores (close to 1.0) in all cases. Furthermore, we conduct a comprehensive ablation study to analyze the factors that may affect the attack performance. Finally, we evaluate multiple defense mechanisms against our backdoor attacks and show that our attacks can practically circumvent these defense mechanisms.
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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.
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Automatic music generation with artificial intelligence typically requires a large amount of data which is hard to obtain for many less common genres and musical instruments. To tackle this issue, we present ongoing work and preliminary findings on the possibility for deep models to transfer knowledge from language to music, by finetuning large language models pre-trained on a massive text corpus on only hundreds of MIDI files of drum performances. We show that by doing so, one of the largest, state-of-the-art models (GPT3) is capable of generating reasonable drum grooves, while models that are not pre-trained (Transformer) shows no such ability beyond naive repetition. Evaluating generated music is a challenging task, more so is evaluating drum grooves with little precedence in literature. Hence, we propose a tailored structural evaluation method and analyze drum grooves produced by GPT3 compared to those played by human professionals, exposing the strengths and weaknesses of such generation by language-to-music transfer. Our findings suggest that language-to-music transfer learning with large language models is viable and promising.
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Few Shot Instance Segmentation (FSIS) requires models to detect and segment novel classes with limited several support examples. In this work, we explore a simple yet unified solution for FSIS as well as its incremental variants, and introduce a new framework named Reference Twice (RefT) to fully explore the relationship between support/query features based on a Transformer-like framework. Our key insights are two folds: Firstly, with the aid of support masks, we can generate dynamic class centers more appropriately to re-weight query features. Secondly, we find that support object queries have already encoded key factors after base training. In this way, the query features can be enhanced twice from two aspects, i.e., feature-level and instance-level. In particular, we firstly design a mask-based dynamic weighting module to enhance support features and then propose to link object queries for better calibration via cross-attention. After the above steps, the novel classes can be improved significantly over our strong baseline. Additionally, our new framework can be easily extended to incremental FSIS with minor modification. When benchmarking results on the COCO dataset for FSIS, gFSIS, and iFSIS settings, our method achieves a competitive performance compared to existing approaches across different shots, e.g., we boost nAP by noticeable +8.2/+9.4 over the current state-of-the-art FSIS method for 10/30-shot. We further demonstrate the superiority of our approach on Few Shot Object Detection. Code and model will be available.
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Graph Neural Networks (GNNs) have shown satisfying performance on various graph learning tasks. To achieve better fitting capability, most GNNs are with a large number of parameters, which makes these GNNs computationally expensive. Therefore, it is difficult to deploy them onto edge devices with scarce computational resources, e.g., mobile phones and wearable smart devices. Knowledge Distillation (KD) is a common solution to compress GNNs, where a light-weighted model (i.e., the student model) is encouraged to mimic the behavior of a computationally expensive GNN (i.e., the teacher GNN model). Nevertheless, most existing GNN-based KD methods lack fairness consideration. As a consequence, the student model usually inherits and even exaggerates the bias from the teacher GNN. To handle such a problem, we take initial steps towards fair knowledge distillation for GNNs. Specifically, we first formulate a novel problem of fair knowledge distillation for GNN-based teacher-student frameworks. Then we propose a principled framework named RELIANT to mitigate the bias exhibited by the student model. Notably, the design of RELIANT is decoupled from any specific teacher and student model structures, and thus can be easily adapted to various GNN-based KD frameworks. We perform extensive experiments on multiple real-world datasets, which corroborates that RELIANT achieves less biased GNN knowledge distillation while maintaining high prediction utility.
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