SHAN: Object-Level Privacy Detection via Inference on Scene Heterogeneous Graph

With the rise of social platforms, protecting privacy has become an important issue. Privacy object detection aims to accurately locate private objects in images. It is the foundation of safeguarding individuals' privacy rights and ensuring responsible data handling practices in the digital age. Since privacy of object is not shift-invariant, the essence of the privacy object detection task is inferring object privacy based on scene information. However, privacy object detection has long been studied as a subproblem of common object detection tasks. Therefore, existing methods suffer from serious deficiencies in accuracy, generalization, and interpretability. Moreover, creating large-scale privacy datasets is difficult due to legal constraints and existing privacy datasets lack label granularity. The granularity of existing privacy detection methods remains limited to the image level. To address the above two issues, we introduce two benchmark datasets for object-level privacy detection and propose SHAN, Scene Heterogeneous graph Attention Network, a model constructs a scene heterogeneous graph from an image and utilizes self-attention mechanisms for scene inference to obtain object privacy. Through experiments, we demonstrated that SHAN performs excellently in privacy object detection tasks, with all metrics surpassing those of the baseline model.

Pre-training-free Image Manipulation Localization through Non-Mutually Exclusive Contrastive Learning

Deep Image Manipulation Localization (IML) models suffer from training data insufficiency and thus heavily rely on pre-training. We argue that contrastive learning is more suitable to tackle the data insufficiency problem for IML. Crafting mutually exclusive positives and negatives is the prerequisite for contrastive learning. However, when adopting contrastive learning in IML, we encounter three categories of image patches: tampered, authentic, and contour patches. Tampered and authentic patches are naturally mutually exclusive, but contour patches containing both tampered and authentic pixels are non-mutually exclusive to them. Simply abnegating these contour patches results in a drastic performance loss since contour patches are decisive to the learning outcomes. Hence, we propose the Non-mutually exclusive Contrastive Learning (NCL) framework to rescue conventional contrastive learning from the above dilemma. In NCL, to cope with the non-mutually exclusivity, we first establish a pivot structure with dual branches to constantly switch the role of contour patches between positives and negatives while training. Then, we devise a pivot-consistent loss to avoid spatial corruption caused by the role-switching process. In this manner, NCL both inherits the self-supervised merits to address the data insufficiency and retains a high manipulation localization accuracy. Extensive experiments verify that our NCL achieves state-of-the-art performance on all five benchmarks without any pre-training and is more robust on unseen real-life samples. The code is available at: https://github.com/Knightzjz/NCL-IML.

Adaptive Gradient Refinement for Adversarial Perturbation Generation

Deep Neural Networks have achieved remarkable success in computer vision, natural language processing, and audio tasks. However, in classification domains, researches proved that Deep neural models are easily fooled and make different or wrong classification prediction, which may cause server results. Many attack methods generate adversarial perturbation with large-scale pixel modification and low cosine-similarity between origin and corresponding adversarial examples, to address these issues, we propose an adversarial method with adaptive adjusting perturbation strength and update gradient in direction to generate attacks, it generate perturbation tensors by adjusting its strength adaptively and update gradient in direction which can escape local minimal or maximal by combining with previous calculate history gradient. In this paper, we evaluate several traditional perturbations creating methods in image classification with ours. Experimental results show that our approach works well and outperform recent techniques in the change of misclassifying image classification, and excellent efficiency in fooling deep network models.