With the growing prevalence of HDR-capable cinema venues such as Cinity LED theaters, there is an increasing demand to convert existing Standard Dynamic Range (SDR) films into High Dynamic Range (HDR) formats for theatrical presentation. However, existing SDR-to-HDR conversion methods are primarily tailored for consumer-grade content such as television and therefore fall short of the stringent requirements of professional cinematic material. To bridge this gap, we present HDRMovie7K, the first large-scale, lossless dataset of cinematic SDR-HDR frame pairs sourced from professional Digital Cinema Distribution Master (DCDM) workflows. Based on this foundation, we introduce HDRMovieformer, a transformer-based framework featuring a Luminance Estimator module for luminance guidance, a Luminance-Guided Multi-Head Self-Attention to focus on critical fine-detail recovery, and a Chroma Refiner for color accuracy, optimized with a novel Wide Color Gamut Loss. To further evaluate our model in online streaming media scenarios, we introduce HDRMovie1K, a dataset curated from publicly available HDR film clips. Extensive experiments on both HDRMovie7K and HDRMovie1K demonstrate that our method achieves state-of-the-art performance.

Arbitrary-scale video super-resolution (VSR) aims to enhance video resolution at continuous scales and has attracted increasing attention in recent years. However, existing methods typically rely on fixed degradation modes, such as bicubic downsampling, which often fail to handle the complex degradations of real-world videos. Current real-world datasets only cover limited scales (e.g., ×2, ×4) and are insufficient to capture the diverse degradations required for arbitrary-scale VSR. To address this, we present RealArbVSR, the first real-world VSR dataset with both integer and decimal scale factors, providing a wider range of degradation levels. Moreover, to generate continuous degradations beyond the collected scales, we propose the Continuous Degradation Generation Network (CDGN), which synthesizes realistic LR videos with arbitrary degradations. Specifically, we design a Scale-aware Degradation Module (SDM) to adaptively learn scale-specific degradations and an Implicit Filter Module (IFM) that represents spatial-temporal features as a continuous feature domain for arbitrary-scale LR frame generation. Extensive experiments demonstrate that our CDGN trained on RealArbVSR produces high-fidelity LR videos with arbitrary degradations and significantly enhances the performance of VSR models in real-world scenarios. The RealArbVSR dataset and source code will be publicly released for further research.

Optimizing user Quality of Experience (QoE) for live video streaming remains a long-standing challenge. The Bitrate Control Algorithm (BCA) plays a crucial role in shaping user QoE. Recent advancements have seen RL-based algorithms overtake traditional rule-based methods, promising enhanced QoE optimization. Nevertheless, our comprehensive study reveals a pressing issue: current RL-based BCAs are limited to the fixed and formulaic reward functions, rendering them ill-equipped to adapt to dynamic network environments and varied viewer preferences. In this work, we present AraLivePro, an automatically adaptive reward learning method that can be seamlessly integrated with any existing learning-based approach in live streaming contexts. To achieve this goal, we have three main designs. First, we construct a dedicated user QoE assessment dataset for live streaming, which includes thousands of videos with millisecond-level metrics. Second, we custom-design an adversarial model that skillfully aligns human feedback with actual network scenarios. Third, we incorporate a QoE-guaranteed reward calibration to deal with the tail-lag effect, which refers to the delayed human feedback caused by network fluctuations near the end of a video segment. We have deployed AraLivePro in practical video streaming systems and conducted massive experiments in comparison to a series of state-of-the-art BCAs. The experimental results demonstrate that AraLivePro not only elevates overall QoE but also exhibits remarkable adaptability to varied network conditions and users.

Object re-identification (ReID) is committed to searching for objects of the same identity across cameras, and its real-world deployment is gradually increasing. Current ReID methods assume that the deployed system follows the centralized processing paradigm, i.e., all computations are conducted in the cloud server and edge devices are only used to capture images. As the number of videos experiences a rapid escalation, this paradigm has become impractical due to the finite computational resources in the cloud server. Therefore, the ReID system should be converted to fit in the cloud-edge collaborative processing paradigm, which is crucial to boost its scalability and practicality. However, current works lack relevant research on this important specific issue, making it difficult to adapt them into a cloud-edge framework effectively. In this paper, we propose a cloud-edge collaborative inference framework for ReID systems, aiming to expedite the return of the desired image captured by the camera to the cloud server by learning the spatial-temporal correlations among objects. In the system, a Distribution-aware Correlation Modeling network (DaCM) is particularly proposed to embed the spatial-temporal correlations of the camera network implicitly into a graph structure, and it can be applied 1) in the cloud to regulate the size of the upload window and 2) on the edge device to adjust the sequence of images, respectively. Notably, the proposed DaCM can be seamlessly combined with traditional ReID methods, enabling their application within our proposed edge-cloud collaborative framework. Extensive experiments demonstrate that our method obviously reduces transmission overhead and significantly improves performance.

Event-based image reconstruction has achieved remarkable progress, benefiting from the high temporal resolution and high dynamic range of event cameras. However, most event-based methods focus on enhancing sRGB image quality, neglecting the potential of leveraging event data for RAW-to-sRGB conversion. Due to the limitations of camera sensors, images processed through standard ISP pipelines often suffer from motion blur and color distortion in dynamic scenes. In contrast, RAW images preserve uncompressed scene information, integrating event signals at this stage enables finer texture recovery and more accurate color correction. To tackle these challenges, we propose EvRAW, a novel event-assisted RAW-to-sRGB image reconstruction network that integrates event signals to promote high-fidelity sRGB image reconstruction. Specifically, we introduce a Motion-guided Structural Enhancement (MSE) module that extracts motion patterns from event streams and aggregates dynamic features to restore fine textures. Additionally, we propose an Adaptive Color Correction (ACC) module that performs region-wise gamma correction and channel-wise color decoding to enhance color fidelity under complex lighting conditions. To evaluate performance in challenging real-world scenarios, we collect a pixel-aligned RAW-Event dataset specifically for this task. Extensive experiments demonstrate that EvRAW achieves state-of-the-art performance in RAW-to-sRGB reconstruction on both synthetic and real-world datasets.

Recently, an increasing number of few-shot image classification methods have been proposed, and they aim at seeking a learning paradigm to train a high-performance classification model with limited labeled samples. However, the neglect of part-level relationships causes few-shot methods to struggle to distinguish between closely similar subcategories, which makes it difficult for them to solve the fine-grained image classification problem. To tackle this challenging task, this paper proposes a fine-grained few-shot image classification method that exploits both intra-part and inter-part relationships among different samples. To establish comprehensive relationships, we first extract multiple discriminative descriptors from the input image, representing its different parts. Then, we propose to define the metric spaces by interpolating intra-part relationships, which can help the model adaptively find clear boundaries for these confusing classes. Finally, since the unlabeled image has high similarities to all classes, we project these similarities into a high-dimension space according to the inter-part relationship and interpolate a parameterized classifier to discover the subtle differences among these similar classes. To evaluate our proposed method, we conduct extensive experiments on various fine-grained datasets. Without any pre-train/fine-tuning process, our approach clearly outperforms previous few-shot learning methods, which demonstrates the effectiveness of our approach.

Exposure correction aims to enhance images suffering from improper exposure to achieve satisfactory visual effects. Despite recent progress, existing methods generally mitigate either overexposure or underexposure in input images, and they still struggle to handle images with mixed exposure, i.e., one image incorporates both overexposed and underexposed regions. The mixed exposure distribution is non-uniform and leads to varying representation, which makes it challenging to address in a unified process. In this paper, we introduce an effective Region-aware Exposure Correction Network (RECNet) that can handle mixed exposure by adaptively learning and bridging different regional exposure representations. Specifically, to address the challenge posed by mixed exposure disparities, we develop a region-aware de-exposure module that effectively translates regional features of mixed exposure scenarios into an exposure-invariant feature space. Simultaneously, as de-exposure operation inevitably reduces discriminative information, we introduce a mixed-scale restoration unit that integrates exposure-invariant features and unprocessed features to recover local information. To further achieve a uniform exposure distribution in the global image, we propose an exposure contrastive regularization strategy under the constraints of intra-regional exposure consistency and inter-regional exposure continuity. Extensive experiments are conducted on various datasets, and the experimental results demonstrate the superiority and generalization of our proposed method. The code is released at: https://github.com/kravrolens/RECNet.

Weakly-supervised temporal action localization aims to locate action regions and identify action categories in untrimmed videos simultaneously by taking only video-level labels as the supervision. Pseudo label generation is a promising strategy to solve the challenging problem, but the current methods ignore the natural temporal structure of the video that can provide rich information to assist such a generation process. In this paper, we propose a novel weakly-supervised temporal action localization method by inferring salient snippet-feature. First, we design a saliency inference module that exploits the variation relationship between temporal neighbor snippets to discover salient snippet-features, which can reflect the significant dynamic change in the video. Secondly, we introduce a boundary refinement module that enhances salient snippet-features through the information interaction unit. Then, a discrimination enhancement module is introduced to enhance the discriminative nature of snippet-features. Finally, we adopt the refined snippet-features to produce high-fidelity pseudo labels, which could be used to supervise the training of the action localization network. Extensive experiments on two publicly available datasets, i.e., THUMOS14 and ActivityNet v1.3, demonstrate our proposed method achieves significant improvements compared to the state-of-the-art methods. Our source code is available at https://github.com/wuli55555/ISSF.

Remarkable advancements have been made in the field of object detection, and given its widespread application, it is of paramount importance to investigate the robustness of detection models. However, previous methods have primarily focused on models based on Convolutional Neural Networks (CNNs), seriously neglecting the Transformer-based models that develop rapidly but exhibit obvious differences in terms of information processing. Therefore, this paper aims to address this gap by exploring potential attacks arising from the self-attention mechanism inhered in Transformer. Specifically, we propose a novel adversarial attack scenario targeting Transformer-based object detection models, where only objects of specific class fail to be detected, while irrelevant objects remain undisturbed. Therefore, human perception is hard to find errors even with the detector fail. To achieve this goal, we introduce an adversarial patch generation method, termed Class-Specific Adversarial (CSAdv) patches, which simultaneously leverages class probability to attack specific objects and utilizes the output from Transformer decoder structures, Query Output, to protect irrelevant objects. Due to the long-range interactions of Transformer, the adversarial patch does not need to directly cover or closely surround the specific objects. Instead, it achieves remote targeted attacks simply by being placed in the corner of image, which greatly enhances the concealment of patches. Extensive experiments are conducted on various benchmark datasets and Transformer-based baselines, and the experimental results show that CSAdv can effectively mask certain class while keeping other classes as unaffected as far as possible.

Exposure correction aims to enhance visual data suffering from improper exposures, which can greatly improve satisfactory visual effects. However, previous methods mainly focus on the image modality, and the video counterpart is less explored in the literature. Directly applying prior image-based methods to videos results in temporal incoherence with low visual quality. Through thorough investigation, we find that the development of relevant communities is limited by the absence of a benchmark dataset. Therefore, in this paper, we construct the first real-world paired video dataset, including both underexposure and overexposure dynamic scenes. To achieve spatial alignment, we utilize two DSLR cameras and a beam splitter to simultaneously capture improper and normal exposure videos. Additionally, we propose an end-to-end video exposure correction network, in which a dual-stream module is designed to deal with both underexposure and overexposure factors, enhancing the illumination based on Retinex theory. The extensive experiments based on various metrics and user studies demonstrate the significance of our dataset and the effectiveness of our method. The code and dataset are available at https://github.com/kravrolens/VECNet.

With the rapid advancements in deep learning technologies, person re-identification (ReID) has witnessed remarkable performance improvements. However, the majority of prior works have traditionally focused on solving the problem via extracting features solely from a single perspective, such as uniform partitioning, attention mechanisms, or semantic masks. While these approaches have demonstrated efficacy within specific contexts, they fall short in diverse situations. In this paper, we propose a novel approach, Mutual Distillation Learning For Person Re-identification (termed as MDPR), which addresses the challenging problem from multiple perspectives within a single unified model, leveraging the power of mutual distillation to enhance the feature representations collectively. Specifically, our approach encompasses two branches: a hard content branch to extract local features via a uniform horizontal partitioning strategy and a soft content branch to dynamically distinguish between foreground and background and facilitate the extraction of multi-granularity features via a carefully designed attention mechanism. To facilitate knowledge exchange between these two branches, a mutual distillation and fusion process is employed, promoting the capability of the outputs of each branch. Extensive experiments are conducted on widely used person ReID datasets to validate the effectiveness and superiority of our approach. Notably, our method achieves an impressive 88.7%/94.4% in mAP/Rank-1 on the DukeMTMC-reID dataset, surpassing the current state-of-the-art results. Our source code is available athttps://github.com/KuilongCui/MDPR.

Fine-grained image classification (FGIC) aims to separate different subcategories from one general superclass, which requires the classification model to extract distinctive representations from subtle yet discriminative regions of the objects. Learning multiple part representations can give a detailed description of the object from different perspectives, boosting the classification performance. However, it still remains a challenging problem to effectively locate diverse parts and extract their features without the assistance of part annotations. In this article, we present a novel method to achieve accurate fine-grained image classification by learning a set of diverse and discriminative part representations without requiring additional supervision. Firstly, our method utilizes a simple attention interaction module to lead learned spatial attentions to focus on different parts, resulting in mutually exclusive part representations. Then, to reduce the impairment of channel coupling among part representations, a part-wise channel weighting module is designed to adjust the amplitudes of different representations adaptively, making them to be diverse along the channel dimension. Moreover, to ensure comprehensive and sufficient part representations, our method introduces multi-granularity feature learning. It enables the extraction of part representations from different semantic and content levels, capturing fine-grained details effectively. To evaluate our method, extensive experiments are conducted on various benchmark fine-grained image datasets, and the results show that our method can achieve outstanding performance for FGIC, demonstrating its effectiveness.

Images captured in low-light conditions often suffer from significant quality degradation. Recent works have built a large variety of deep Retinex-based networks to enhance low-light images. The Retinex-based methods require decomposing the image into reflectance and illumination components, which is a highly ill-posed problem and there is no available ground truth. Previous works addressed this problem by imposing some additional priors or regularizers. However, finding an effective prior or regularizer that can be applied in various scenes is challenging, and the performance of the model suffers from too many additional constraints. We propose a contrastive learning method and a self-knowledge distillation method for Retinex decomposition that allow training our Retinex-based model without elaborate hand-crafted regularization functions. Rather than estimating reflectance and illuminance images and representing the final images as their element-wise products as in previous works, our regularizer-free Retinex decomposition and synthesis network (RFR) extracts reflectance and illuminance features and synthesizes them end-to-end. In addition, we propose a loss function for contrastive learning and a progressive learning strategy for self-knowledge distillation. Extensive experimental results demonstrate that our proposed methods can achieve superior performance compared with state-of-the-art approaches.

Fine-grained image classification focuses on distinguishing objects from different similar subcategories, which requires the classification model to extract subtle yet discriminative descriptors. Recent Vision Transformer (ViT) has shown an enormous potential for this challenging task, but previous ViT-based methods have primarily focused on improving the relationship between image patches, neglecting the limited expressive capability caused by the single class token.To address this limitation, we propose to learn a Multi-part Token Transformer (MpT-Trans), which extends the class token to multiple tokens presenting various parts, enhancing the model's capability of extracting discriminative information. Specifically, our MpT-Trans model interpolates the vision transformer framework with two modules: (i) the Part-wise Shift Learning (PwSL) module is proposed to extend the single class token to a set of part tokens with differentiable shifts, enabling the model to extract informative representations from different perspectives; (ii) the Dual Contrastive Learning (DuCL) module is introduced to exploit the inter-class and inter-part relationships to regularize the learning of part tokens, enhancing their diversity and discrimination for accurate classification. Extensive experiments and ablation study demonstrate that the proposed MpT-Trans achieves state-of-the-art performance on various fine-grained image benchmark datasets, demonstrating the effectiveness of our proposed method.

Recently, it is gaining increasingly attention to incorporate self-supervised technologies into few-shot learning. Previous methods have exclusively focused on image-level self-supervision, but they ignore that capturing subtle part features plays an important role in distinguishing fine-grained images. In this paper, we propose an approach named PaCL that embeds part-level contrastive learning into fine-grained few-shot image classification, strengthening the models' capability to extract discriminative features from indistinguishable images. PaCL treats parts as the inputs of contrastive learning, and it uses a transformation module to involve image-specific information into pre-defined meta parts, generating multiple features from each meta part depending on different images. To alleviate the impact of changes in views or occlusions, we propose to adopt part prototypes in contrastive learning. Part prototypes are generated by aggregating the features of each certain type of part, which are more reliable than directly using part features. A few-shot classifier is adopted to predict query images, which calculates the classification loss to optimize the transformation module and meta parts in conjunction with the loss calculated in contrastive learning. The optimization process will enforce the model to learn to extract discriminative and diverse features from different parts of the objects, even for the samples of unseen classes. Extensive studies show that our proposed method improves the performance of fine-grained few-shot image classification across several backbones, datasets, and tasks, achieving superior results compared with state-of-the-art methods.

Fine-grained vehicle recognition is a challenging problem due to the subtle intra-category appearance variation, which requires the recognition model can capture discriminative features from distinguishing regions. The structure is an important characteristic of vehicles which can help to find substantial parts and learn distinguishing representations. In this paper, we propose an approach that introduces the structure graph into consideration to learn distinguishing representations for vehicle recognition. Our proposed method first constructs a global structure graph from the features generated by the convolutional network and then it applies the graph as the guidance to produce effective representations of vehicles. The results of extensive experiments demonstrate that our proposed method can produce more promising results than other state-of-the-art methods. The results of the visualization illustrate that our approach can construct a suitable structure graph and the global structure information facilitates learning discriminative representations at crucial parts of vehicles.