快捷方式学习对深度学习模型很常见，但导致了退化的特征表示形式，因此危害了该模型的可推广性和解释性。但是，在广泛使用的视觉变压器框架中的快捷方式学习在很大程度上是未知的。同时，引入特定领域的知识是纠正捷径的主要方法，捷径为背景相关因素。例如，在医学成像领域中，放射科医生的眼睛凝视数据是一种有效的人类视觉先验知识，具有指导深度学习模型的巨大潜力，可以专注于有意义的前景区域。但是，获得眼睛凝视数据是时必的，劳动密集型的，有时甚至是不切实际的。在这项工作中，我们提出了一种新颖而有效的显着性视觉变压器（SGT）模型，以在没有眼神数据的情况下在VIT中纠正快捷方式学习。具体而言，采用计算视觉显着性模型来预测输入图像样本的显着性图。然后，显着图用于散布最有用的图像贴片。在拟议的中士中，图像贴片之间的自我注意力仅集中于蒸馏的信息。考虑到这种蒸馏操作可能会导致全局信息丢失，我们在最后一个编码器层中进一步介绍了一个残留的连接，该连接捕获了所有图像贴片中的自我注意力。四个独立公共数据集的实验结果表明，我们的SGT框架可以有效地学习和利用人类的先验知识，而无需眼睛凝视数据，并且比基线更好。同时，它成功地纠正了有害的快捷方式学习并显着提高了VIT模型的解释性，证明了传递人类先验知识在纠正快捷方式学习方面传递人类先验知识的承诺

通常，对于基于深网的良好性能文本检测器获得良好的培训和长期培训计算是必要的。在本文中，我们提出了一个新的场景文本检测网络（称为狂热者），其快速收敛速度和准确的文本本地化。所提出的粉丝是基于变压器特征学习和标准化的傅立叶描述符建模的端到端文本检测器，在该图案中，傅立叶描述符建议网络和迭代文本解码网络旨在有效，准确地识别文本建议。此外，还提出了一个密集的匹配策略和精心设计的损失函数，以优化网络性能。进行了广泛的实验，以证明所提出的粉丝可以通过更少的训练时期和没有预训练来实现SOTA性能。当我们引入其他数据进行预训练时，提出的粉丝可以在MSRATD500，CTW1500和TotalText上实现SOTA性能。消融实验还验证了我们贡献的有效性。

在本文中，我们提出了两种技术，即联合建模和数据增强，以改善视听场景分类（AVSC）的系统性能。我们采用仅在图像数据集中培训的预训练网络来提取视频嵌入；而对于音频嵌入模型，我们决定从头开始训练它们。我们探索不同的神经网络体系结构，以有效地结合视频和音频方式。此外，研究了数据增强策略以增加视听训练设置的规模。对于视频方式，验证了兰德金几个操作的有效性。提出了Audio-Video关节混合方案，以进一步改善AVSC的性能。在Tau Urban Audio Visual Spacees 2021的开发集中，我们的最终系统可以在提交给Dcase 2021 Task 1B的所有单个AVSC系统中达到94.2％的最佳准确性。

Deep learning models can achieve high accuracy when trained on large amounts of labeled data. However, real-world scenarios often involve several challenges: Training data may become available in installments, may originate from multiple different domains, and may not contain labels for training. Certain settings, for instance medical applications, often involve further restrictions that prohibit retention of previously seen data due to privacy regulations. In this work, to address such challenges, we study unsupervised segmentation in continual learning scenarios that involve domain shift. To that end, we introduce GarDA (Generative Appearance Replay for continual Domain Adaptation), a generative-replay based approach that can adapt a segmentation model sequentially to new domains with unlabeled data. In contrast to single-step unsupervised domain adaptation (UDA), continual adaptation to a sequence of domains enables leveraging and consolidation of information from multiple domains. Unlike previous approaches in incremental UDA, our method does not require access to previously seen data, making it applicable in many practical scenarios. We evaluate GarDA on two datasets with different organs and modalities, where it substantially outperforms existing techniques.

The development of social media user stance detection and bot detection methods rely heavily on large-scale and high-quality benchmarks. However, in addition to low annotation quality, existing benchmarks generally have incomplete user relationships, suppressing graph-based account detection research. To address these issues, we propose a Multi-Relational Graph-Based Twitter Account Detection Benchmark (MGTAB), the first standardized graph-based benchmark for account detection. To our knowledge, MGTAB was built based on the largest original data in the field, with over 1.55 million users and 130 million tweets. MGTAB contains 10,199 expert-annotated users and 7 types of relationships, ensuring high-quality annotation and diversified relations. In MGTAB, we extracted the 20 user property features with the greatest information gain and user tweet features as the user features. In addition, we performed a thorough evaluation of MGTAB and other public datasets. Our experiments found that graph-based approaches are generally more effective than feature-based approaches and perform better when introducing multiple relations. By analyzing experiment results, we identify effective approaches for account detection and provide potential future research directions in this field. Our benchmark and standardized evaluation procedures are freely available at: https://github.com/GraphDetec/MGTAB.

As one of the prevalent methods to achieve automation systems, Imitation Learning (IL) presents a promising performance in a wide range of domains. However, despite the considerable improvement in policy performance, the corresponding research on the explainability of IL models is still limited. Inspired by the recent approaches in explainable artificial intelligence methods, we proposed a model-agnostic explaining framework for IL models called R2RISE. R2RISE aims to explain the overall policy performance with respect to the frames in demonstrations. It iteratively retrains the black-box IL model from the randomized masked demonstrations and uses the conventional evaluation outcome environment returns as the coefficient to build an importance map. We also conducted experiments to investigate three major questions concerning frames' importance equality, the effectiveness of the importance map, and connections between importance maps from different IL models. The result shows that R2RISE successfully distinguishes important frames from the demonstrations.

Compressed videos often exhibit visually annoying artifacts, known as Perceivable Encoding Artifacts (PEAs), which dramatically degrade video visual quality. Subjective and objective measures capable of identifying and quantifying various types of PEAs are critical in improving visual quality. In this paper, we investigate the influence of four spatial PEAs (i.e. blurring, blocking, bleeding, and ringing) and two temporal PEAs (i.e. flickering and floating) on video quality. For spatial artifacts, we propose a visual saliency model with a low computational cost and higher consistency with human visual perception. In terms of temporal artifacts, self-attention based TimeSFormer is improved to detect temporal artifacts. Based on the six types of PEAs, a quality metric called Saliency-Aware Spatio-Temporal Artifacts Measurement (SSTAM) is proposed. Experimental results demonstrate that the proposed method outperforms state-of-the-art metrics. We believe that SSTAM will be beneficial for optimizing video coding techniques.

We propose a distributionally robust return-risk model for Markov decision processes (MDPs) under risk and reward ambiguity. The proposed model optimizes the weighted average of mean and percentile performances, and it covers the distributionally robust MDPs and the distributionally robust chance-constrained MDPs (both under reward ambiguity) as special cases. By considering that the unknown reward distribution lies in a Wasserstein ambiguity set, we derive the tractable reformulation for our model. In particular, we show that that the return-risk model can also account for risk from uncertain transition kernel when one only seeks deterministic policies, and that a distributionally robust MDP under the percentile criterion can be reformulated as its nominal counterpart at an adjusted risk level. A scalable first-order algorithm is designed to solve large-scale problems, and we demonstrate the advantages of our proposed model and algorithm through numerical experiments.

Witnessing the impressive achievements of pre-training techniques on large-scale data in the field of computer vision and natural language processing, we wonder whether this idea could be adapted in a grab-and-go spirit, and mitigate the sample inefficiency problem for visuomotor driving. Given the highly dynamic and variant nature of the input, the visuomotor driving task inherently lacks view and translation invariance, and the visual input contains massive irrelevant information for decision making, resulting in predominant pre-training approaches from general vision less suitable for the autonomous driving task. To this end, we propose PPGeo (Policy Pre-training via Geometric modeling), an intuitive and straightforward fully self-supervised framework curated for the policy pretraining in visuomotor driving. We aim at learning policy representations as a powerful abstraction by modeling 3D geometric scenes on large-scale unlabeled and uncalibrated YouTube driving videos. The proposed PPGeo is performed in two stages to support effective self-supervised training. In the first stage, the geometric modeling framework generates pose and depth predictions simultaneously, with two consecutive frames as input. In the second stage, the visual encoder learns driving policy representation by predicting the future ego-motion and optimizing with the photometric error based on current visual observation only. As such, the pre-trained visual encoder is equipped with rich driving policy related representations and thereby competent for multiple visuomotor driving tasks. Extensive experiments covering a wide span of challenging scenarios have demonstrated the superiority of our proposed approach, where improvements range from 2% to even over 100% with very limited data. Code and models will be available at https://github.com/OpenDriveLab/PPGeo.

As one of the most important psychic stress reactions, micro-expressions (MEs), are spontaneous and transient facial expressions that can reveal the genuine emotions of human beings. Thus, recognizing MEs (MER) automatically is becoming increasingly crucial in the field of affective computing, and provides essential technical support in lie detection, psychological analysis and other areas. However, the lack of abundant ME data seriously restricts the development of cutting-edge data-driven MER models. Despite the recent efforts of several spontaneous ME datasets to alleviate this problem, it is still a tiny amount of work. To solve the problem of ME data hunger, we construct a dynamic spontaneous ME dataset with the largest current ME data scale, called DFME (Dynamic Facial Micro-expressions), which includes 7,526 well-labeled ME videos induced by 671 participants and annotated by more than 20 annotators throughout three years. Afterwards, we adopt four classical spatiotemporal feature learning models on DFME to perform MER experiments to objectively verify the validity of DFME dataset. In addition, we explore different solutions to the class imbalance and key-frame sequence sampling problems in dynamic MER respectively on DFME, so as to provide a valuable reference for future research. The comprehensive experimental results show that our DFME dataset can facilitate the research of automatic MER, and provide a new benchmark for MER. DFME will be published via https://mea-lab-421.github.io.