One of the main challenges in deep learning-based underwater image enhancement is the limited availability of high-quality training data. Underwater images are difficult to capture and are often of poor quality due to the distortion and loss of colour and contrast in water. This makes it difficult to train supervised deep learning models on large and diverse datasets, which can limit the model's performance. In this paper, we explore an alternative approach to supervised underwater image enhancement. Specifically, we propose a novel unsupervised underwater image enhancement framework that employs a conditional variational autoencoder (cVAE) to train a deep learning model with probabilistic adaptive instance normalization (PAdaIN) and statistically guided multi-colour space stretch that produces realistic underwater images. The resulting framework is composed of a U-Net as a feature extractor and a PAdaIN to encode the uncertainty, which we call UDnet. To improve the visual quality of the images generated by UDnet, we use a statistically guided multi-colour space stretch module that ensures visual consistency with the input image and provides an alternative to training using a ground truth image. The proposed model does not need manual human annotation and can learn with a limited amount of data and achieves state-of-the-art results on underwater images. We evaluated our proposed framework on eight publicly-available datasets. The results show that our proposed framework yields competitive performance compared to other state-of-the-art approaches in quantitative as well as qualitative metrics. Code available at https://github.com/alzayats/UDnet .

当有足够的训练数据时，在某些视力任务中，基于变压器的模型（例如Vision Transformer（VIT））可以超越跨趋化神经网络（CNN）。然而，（CNN）对视力任务（即翻译均衡和局部性）具有强大而有用的归纳偏见。在这项工作中，我们开发了一种新颖的模型架构，我们称之为移动鱼类地标检测网络（MFLD-NET）。我们已经使用基于VIT的卷积操作（即斑块嵌入，多层感知器）制作了该模型。 MFLD-NET可以在轻巧的同时获得竞争性或更好的结果，同时轻巧，因此适用于嵌入式和移动设备。此外，我们表明MFLD-NET可以在PAR上获得关键点（地标）估计精度，甚至比FISH图像数据集上的某些最先进的（CNN）更好。此外，与VIT不同，MFLD-NET不需要预训练的模型，并且在小型数据集中训练时可以很好地概括。我们提供定量和定性的结果，以证明该模型的概括能力。这项工作将为未来开发移动但高效的鱼类监测系统和设备的努力奠定基础。

基于高质量标签的鱼类跟踪和细分的DNN很昂贵。替代无监督的方法取决于视频数据中自然发生的空间和时间变化来生成嘈杂的伪界图标签。这些伪标签用于训练多任务深神经网络。在本文中，我们提出了一个三阶段的框架，用于强大的鱼类跟踪和分割，其中第一阶段是光流模型，该模型使用帧之间的空间和时间一致性生成伪标签。在第二阶段，一个自我监督的模型会逐步完善伪标签。在第三阶段，精制标签用于训练分割网络。在培训或推理期间没有使用人类注释。进行了广泛的实验来验证我们在三个公共水下视频数据集中的方法，并证明它对视频注释和细分非常有效。我们还评估框架对不同成像条件的鲁棒性，并讨论当前实施的局限性。

海洋生态系统及其鱼类栖息地越来越重要，因为它们在提供有价值的食物来源和保护效果方面的重要作用。由于它们的偏僻且难以接近自然，因此通常使用水下摄像头对海洋环境和鱼类栖息地进行监测。这些相机产生了大量数字数据，这些数据无法通过当前的手动处理方法有效地分析，这些方法涉及人类观察者。 DL是一种尖端的AI技术，在分析视觉数据时表现出了前所未有的性能。尽管它应用于无数领域，但仍在探索其在水下鱼类栖息地监测中的使用。在本文中，我们提供了一个涵盖DL的关键概念的教程，该教程可帮助读者了解对DL的工作原理的高级理解。该教程还解释了一个逐步的程序，讲述了如何为诸如水下鱼类监测等挑战性应用开发DL算法。此外，我们还提供了针对鱼类栖息地监测的关键深度学习技术的全面调查，包括分类，计数，定位和细分。此外，我们对水下鱼类数据集进行了公开调查，并比较水下鱼类监测域中的各种DL技术。我们还讨论了鱼类栖息地加工深度学习的新兴领域的一些挑战和机遇。本文是为了作为希望掌握对DL的高级了解，通过遵循我们的分步教程而为其应用开发的海洋科学家的教程，并了解如何发展其研究，以促进他们的研究。努力。同时，它适用于希望调查基于DL的最先进方法的计算机科学家，以进行鱼类栖息地监测。

由于水下环境复杂，水下鱼类分割以估计鱼体测量值仍然无法解决。依靠完全监督的分割模型需要收集每个像素标签，这很耗时且容易过度拟合。自我监督的学习方法可以帮助避免大型注释的培训数据集的要求，但是，在现实世界中，它们应该达到良好的细分质量。在本文中，我们介绍了一种基于变压器的方法，该方法使用自学意义重大的鱼类分割。我们提出的模型对视频进行了培训 - 没有任何注释，可以在野外现场拍摄的水下视频中进行鱼类分割。我们表明，当对一个数据集的一系列水下视频进行培训时，该建议的模型超过了以前的基于CNN的基于CNN和基于变压器的自我监督方法，并在两个未见的水下视频数据集中相对接近具有监督方法的性能。这表明了我们的模型的概括性以及它不需要预培训模型的事实。此外，我们表明，由于其密集的表示学习，我们的模型是计算效率的。我们提供定量和定性的结果，以证明我们的模型的重要功能。

Datasets for training recommender systems are often subject to distribution shift induced by users' and recommenders' selection biases. In this paper, we study the impact of selection bias on datasets with different quantization. We then leverage two differently quantized datasets from different source distributions to mitigate distribution shift by applying the inverse probability scoring method from causal inference. Empirically, our approach gains significant performance improvement over single-dataset methods and alternative ways of combining two datasets.

We consider the problem of continually releasing an estimate of the population mean of a stream of samples that is user-level differentially private (DP). At each time instant, a user contributes a sample, and the users can arrive in arbitrary order. Until now these requirements of continual release and user-level privacy were considered in isolation. But, in practice, both these requirements come together as the users often contribute data repeatedly and multiple queries are made. We provide an algorithm that outputs a mean estimate at every time instant $t$ such that the overall release is user-level $\varepsilon$-DP and has the following error guarantee: Denoting by $M_t$ the maximum number of samples contributed by a user, as long as $\tilde{\Omega}(1/\varepsilon)$ users have $M_t/2$ samples each, the error at time $t$ is $\tilde{O}(1/\sqrt{t}+\sqrt{M}_t/t\varepsilon)$. This is a universal error guarantee which is valid for all arrival patterns of the users. Furthermore, it (almost) matches the existing lower bounds for the single-release setting at all time instants when users have contributed equal number of samples.

A fundamental characteristic common to both human vision and natural language is their compositional nature. Yet, despite the performance gains contributed by large vision and language pretraining, we find that - across 6 architectures trained with 4 algorithms on massive datasets - they exhibit little compositionality. To arrive at this conclusion, we introduce a new compositionality evaluation benchmark CREPE which measures two important aspects of compositionality identified by cognitive science literature: systematicity and productivity. To measure systematicity, CREPE consists of three test datasets. The three test sets are designed to test models trained on three of the popular training datasets: CC-12M, YFCC-15M, and LAION-400M. They contain 385K, 385K, and 373K image-text pairs and 237K, 210K, and 178K hard negative captions. To test productivity, CREPE contains 17K image-text pairs with nine different complexities plus 246K hard negative captions with atomic, swapping, and negation foils. The datasets are generated by repurposing the Visual Genome scene graphs and region descriptions and applying handcrafted templates and GPT-3. For systematicity, we find that model performance decreases consistently when novel compositions dominate the retrieval set, with Recall@1 dropping by up to 8%. For productivity, models' retrieval success decays as complexity increases, frequently nearing random chance at high complexity. These results hold regardless of model and training dataset size.

The lack of standardization is a prominent issue in magnetic resonance (MR) imaging. This often causes undesired contrast variations due to differences in hardware and acquisition parameters. In recent years, MR harmonization using image synthesis with disentanglement has been proposed to compensate for the undesired contrast variations. Despite the success of existing methods, we argue that three major improvements can be made. First, most existing methods are built upon the assumption that multi-contrast MR images of the same subject share the same anatomy. This assumption is questionable since different MR contrasts are specialized to highlight different anatomical features. Second, these methods often require a fixed set of MR contrasts for training (e.g., both Tw-weighted and T2-weighted images must be available), which limits their applicability. Third, existing methods generally are sensitive to imaging artifacts. In this paper, we present a novel approach, Harmonization with Attention-based Contrast, Anatomy, and Artifact Awareness (HACA3), to address these three issues. We first propose an anatomy fusion module that enables HACA3 to respect the anatomical differences between MR contrasts. HACA3 is also robust to imaging artifacts and can be trained and applied to any set of MR contrasts. Experiments show that HACA3 achieves state-of-the-art performance under multiple image quality metrics. We also demonstrate the applicability of HACA3 on downstream tasks with diverse MR datasets acquired from 21 sites with different field strengths, scanner platforms, and acquisition protocols.

Machine learning models are known to be susceptible to adversarial perturbation. One famous attack is the adversarial patch, a sticker with a particularly crafted pattern that makes the model incorrectly predict the object it is placed on. This attack presents a critical threat to cyber-physical systems that rely on cameras such as autonomous cars. Despite the significance of the problem, conducting research in this setting has been difficult; evaluating attacks and defenses in the real world is exceptionally costly while synthetic data are unrealistic. In this work, we propose the REAP (REalistic Adversarial Patch) benchmark, a digital benchmark that allows the user to evaluate patch attacks on real images, and under real-world conditions. Built on top of the Mapillary Vistas dataset, our benchmark contains over 14,000 traffic signs. Each sign is augmented with a pair of geometric and lighting transformations, which can be used to apply a digitally generated patch realistically onto the sign. Using our benchmark, we perform the first large-scale assessments of adversarial patch attacks under realistic conditions. Our experiments suggest that adversarial patch attacks may present a smaller threat than previously believed and that the success rate of an attack on simpler digital simulations is not predictive of its actual effectiveness in practice. We release our benchmark publicly at https://github.com/wagner-group/reap-benchmark.