CVPR 2024 论文列表

Tracking with bio-inspired event cameras has garnered increasing interest in recent years. Existing works either utilize aligned RGB and event data for accurate tracking or directly learn an event-based tracker. The former incurs higher inference costs while the latter may be susceptible to the impact of noisy events or sparse spatial resolution. In this paper we propose a novel hierarchical knowledge distillation framework that can fully utilize multi-modal / multi-view information during training to facilitate knowledge transfer enabling us to achieve high-speed and low-latency visual tracking during testing by using only event signals. Specifically a teacher Transformer-based multi-modal tracking framework is first trained by feeding the RGB frame and event stream simultaneously. Then we design a new hierarchical knowledge distillation strategy which includes pairwise similarity feature representation and response maps-based knowledge distillation to guide the learning of the student Transformer network. In particular since existing event-based tracking datasets are all low-resolution (346 * 260) we propose the first large-scale high-resolution (1280 * 720) dataset named EventVOT. It contains 1141 videos and covers a wide range of categories such as pedestrians vehicles UAVs ping pong etc. Extensive experiments on both low-resolution (FE240hz VisEvent COESOT) and our newly proposed high-resolution EventVOT dataset fully validated the effectiveness of our proposed method. The dataset evaluation toolkit and source code will be released.

We present a new egocentric procedural error dataset containing videos with various types of errors as well as normal videos and propose a new framework for procedural error detection using error-free training videos only. Our framework consists of an action segmentation model and a contrastive step prototype learning module to segment actions and learn useful features for error detection. Based on the observation that interactions between hands and objects often inform action and error understanding we propose to combine holistic frame features with relations features which we learn by building a graph using active object detection followed by a Graph Convolutional Network. To handle errors unseen during training we use our contrastive step prototype learning to learn multiple prototypes for each step capturing variations of error-free step executions. At inference time we use feature-prototype similarities for error detection. By experiments on three datasets we show that our proposed framework outperforms state-of-the-art video anomaly detection methods for error detection and provides smooth action and error predictions.

In this work we present a novel perspective on detecting out-of-distribution (OOD) samples and propose an algorithm for sample-aware model selection to enhance the effectiveness of OOD detection. Our algorithm determines for each test input which pre-trained models in the model zoo are capable of identifying the test input as an OOD sample. If no such models exist in the model zoo the test input is classified as an in-distribution (ID) sample. We theoretically demonstrate that our method maintains the true positive rate of ID samples and accurately identifies OOD samples with high probability when there are a sufficient number of diverse pre-trained models in the model zoo. Extensive experiments were conducted to validate our method demonstrating that it leverages the complementarity among single-model detectors to consistently improve the effectiveness of OOD sample identification. Compared to base-line methods our approach improved the relative performance by 65.40% and 37.25% on the CIFAR10 and ImageNet benchmarks respectively.

Multi-camera-based 3D object detection has made notable progress in the past several years. However we observe that there are cases (e.g. faraway regions) in which popular 2D object detectors are more reliable than state-of-the-art 3D detectors. In this paper to improve the performance of query-based 3D object detectors we present a novel query generating approach termed QAF2D which infers 3D query anchors from 2D detection results. A 2D bounding box of an object in an image is lifted to a set of 3D anchors by associating each sampled point within the box with depth yaw angle and size candidates. Then the validity of each 3D anchor is verified by comparing its projection in the image with its corresponding 2D box and only valid anchors are kept and used to construct queries. The class information of the 2D bounding box associated with each query is also utilized to match the predicted boxes with ground truth for the set-based loss. The image feature extraction backbone is shared between the 3D detector and 2D detector by adding a small number of prompt parameters. We integrate QAF2D into three popular query-based 3D object detectors and carry out comprehensive evaluations on the nuScenes dataset. The largest improvement that QAF2D can bring about on the nuScenes validation subset is 2.3% NDS and 2.7% mAP. Code is available at https://github.com/max-vision/QAF2D.

The Segment Anything Model (SAM) a prompt-driven foundational model has demonstrated remarkable performance in natural image segmentation. However its application in video camouflaged object detection (VCOD) encounters challenges chiefly stemming from the overlooked temporal-spatial associations and the unreliability of user-provided prompts for camouflaged objects that are difficult to discern with the naked eye. To tackle the above issues we endow SAM with keen eyes and propose the Temporal-spatial Prompt SAM (TSP-SAM) a novel approach tailored for VCOD via an ingenious prompted learning scheme. Firstly motion-driven self-prompt learning is employed to capture the camouflaged object thereby bypassing the need for user-provided prompts. With the detected subtle motion cues across consecutive video frames the overall movement of the camouflaged object is captured for more precise spatial localization. Subsequently to eliminate the prompt bias resulting from inter-frame discontinuities the long-range consistency within the video sequences is taken into account to promote the robustness of the self-prompts. It is also injected into the encoder of SAM to enhance the representational capabilities. Extensive experimental results on two benchmarks demonstrate that the proposed TSP-SAM achieves a significant improvement over the state-of-the-art methods. With the mIoU metric increasing by 7.8% and 9.6% TSP-SAM emerges as a groundbreaking step forward in the field of VCOD.

Recently temporal action detection (TAD) has seen significant performance improvement with end-to-end training. However due to the memory bottleneck only models with limited scales and limited data volumes can afford end-to-end training which inevitably restricts TAD performance. In this paper we reduce the memory consumption for end-to-end training and manage to scale up the TAD backbone to 1 billion parameters and the input video to 1536 frames leading to significant detection performance. The key to our approach lies in our proposed temporal-informative adapter (TIA) which is a novel lightweight module that reduces training memory. Using TIA we free the humongous backbone from learning to adapt to the TAD task by only updating the parameters in TIA. TIA also leads to better TAD representation by temporally aggregating context from adjacent frames throughout the backbone. We evaluate our model across four representative datasets. Owing to our efficient design we are able to train end-to-end on VideoMAEv2-giant and achieve 75.4% mAP on THUMOS14 being the first end-to-end model to outperform the best feature-based methods.

Group synchronization plays a crucial role in global pipelines for Structure from Motion (SfM). Its formulation is nonconvex and it is faced with highly corrupted measurements. Cycle consistency has been effective in addressing these challenges. However computationally efficient solutions are needed for cycles longer than three especially in practical scenarios where 3-cycles are unavailable. To overcome this computational bottleneck we propose an algorithm for group synchronization that leverages information from cycles of lengths ranging from three to six with a complexity of O(n^3) (or O(n^ 2.373 ) when using a faster matrix multiplication algorithm). We establish non-trivial theory for this and related methods that achieves competitive sample complexity assuming the uniform corruption model. To advocate the practical need for our method we consider distributed group synchronization which requires at least 4-cycles and we illustrate state-of-the-art performance by our method in this context.

Image-based mirror detection has recently undergone rapid research due to its significance in applications such as robotic navigation semantic segmentation and scene reconstruction. Recently VMD-Net was proposed as the first video mirror detection technique by modeling dual correspondences between the inside and outside of the mirror both spatially and temporally. However this approach is not reliable as correspondences can occur completely inside or outside of the mirrors. In addition the proposed dataset VMD-D contains many small mirrors limiting its applicability to real-world scenarios. To address these problems we developed a more challenging dataset that includes mirrors of various shapes and sizes at different locations of the frames providing a better reflection of real-world scenarios. Next we observed that the motions between the inside and outside of the mirror are often inconsistent. For instance when moving in front of a mirror the motion inside the mirror is often much smaller than the motion outside due to increased depth perception. With these observations we propose modeling inconsistent motion cues to detect mirrors and a new network with two novel modules. The Motion Attention Module (MAM) explicitly models inconsistent motions around mirrors via optical flow and the Motion-Guided Edge Detection Module (MEDM) uses motions to guide mirror edge feature learning. Experimental results on our proposed dataset show that our method outperforms state-of-the-arts. The code and dataset are available at https://github.com/AlexAnthonyWarren/MG-VMD.

This paper views the DETR's non-duplicate detection ability as a competition result among object queries. Around each object there are usually multiple queries within which only a single one can win the chance to become the final detection. Such a competition is hard: while some competing queries initially have very close prediction scores their leading query has to dramatically enlarge its score superiority after several decoder layers. To help the leading query stands out this paper proposes EASE-DETR which eases the competition by introducing bias that favours the leading one. EASE-DETR is very simple: in every intermediate decoder layer we identify the "leading / trailing" relationship between any two queries and encode this binary relationship into the following decoder layer to amplify the superiority of the leading one. More concretely the leading query is to be protected from mutual query suppression in the self-attention layer and encouraged to absorb more object features in the cross-attention layer therefore accelerating to win. Experimental results show that EASE-DETR brings consistent and remarkable improvement to various DETRs.

Semantic segmentation has innately relied on extensive pixel-level annotated data leading to the emergence of unsupervised methodologies. Among them leveraging self-supervised Vision Transformers for unsupervised semantic segmentation (USS) has been making steady progress with expressive deep features. Yet for semantically segmenting images with complex objects a predominant challenge remains: the lack of explicit object-level semantic encoding in patch-level features. This technical limitation often leads to inadequate segmentation of complex objects with diverse structures. To address this gap we present a novel approach EAGLE which emphasizes object-centric representation learning for unsupervised semantic segmentation. Specifically we introduce EiCue a spectral technique providing semantic and structural cues through an eigenbasis derived from the semantic similarity matrix of deep image features and color affinity from an image. Further by incorporating our object-centric contrastive loss with EiCue we guide our model to learn object-level representations with intra- and inter-image object-feature consistency thereby enhancing semantic accuracy. Extensive experiments on COCO-Stuff Cityscapes and Potsdam-3 datasets demonstrate the state-of-the-art USS results of EAGLE with accurate and consistent semantic segmentation across complex scenes.

Unsupervised video object segmentation (VOS) aims to detect and segment the most salient object in videos. The primary techniques used in unsupervised VOS are 1) the collaboration of appearance and motion information; and 2) temporal fusion between different frames. This paper proposes two novel prototype-based attention mechanisms inter-modality attention (IMA) and inter-frame attention (IFA) to incorporate these techniques via dense propagation across different modalities and frames. IMA densely integrates context information from different modalities based on a mutual refinement. IFA injects global context of a video to the query frame enabling a full utilization of useful properties from multiple frames. Experimental results on public benchmark datasets demonstrate that our proposed approach outperforms all existing methods by a substantial margin. The proposed two components are also thoroughly validated via ablative study.

In the context of pose-invariant object recognition and retrieval we demonstrate that it is possible to achieve significant improvements in performance if both the category-based and the object-identity-based embeddings are learned simultaneously during training. In hindsight that sounds intuitive because learning about the categories is more fundamental than learning about the individual objects that correspond to those categories. However to the best of what we know no prior work in pose invariant learning has demonstrated this effect. This paper presents an attention-based dual-encoder architecture with specially designed loss functions that optimize the inter- and intra-class distances simultaneously in two different embedding spaces one for the category embeddings and the other for the object level embeddings. The loss functions we have proposed are pose-invariant ranking losses that are designed to minimize the intra-class distances and maximize the inter-class distances in the dual representation spaces. We demonstrate the power of our approach with three challenging multi-view datasets ModelNet-40 ObjectPI and FG3D. With our dual approach for single view object recognition we outperform the previous best by 20.0% on ModelNet40 2.0% on ObjectPI and 46.5% on FG3D. On the other hand for single-view object retrieval we outperform the previous best by 33.7% on ModelNet40 18.8% on ObjectPI and 56.9% on FG3D.

Temporal Action Detection (TAD) aims to identify the action boundaries and the corresponding category within untrimmed videos. Inspired by the success of DETR in object detection several methods have adapted the query-based framework to the TAD task. However these approaches primarily followed DETR to predict actions at the instance level (i.e. identify each action by its center point) leading to sub-optimal boundary localization. To address this issue we propose a new Dual-level query-based TAD framework namely DualDETR to detect actions from both instance-level and boundary-level. Decoding at different levels requires semantics of different granularity therefore we introduce a two-branch decoding structure. This structure builds distinctive decoding processes for different levels facilitating explicit capture of temporal cues and semantics at each level. On top of the two-branch design we present a joint query initialization strategy to align queries from both levels. Specifically we leverage encoder proposals to match queries from each level in a one-to-one manner. Then the matched queries are initialized using position and content prior from the matched action proposal. The aligned dual-level queries can refine the matched proposal with complementary cues during subsequent decoding. We evaluate DualDETR on three challenging multi-label TAD benchmarks. The experimental results demonstrate the superior performance of DualDETR to the existing state-of-the-art methods achieving a substantial improvement under det-mAP and delivering impressive results under seg-mAP.

Saliency object ranking (SOR) has attracted significant attention recently. Previous methods usually failed to explicitly explore the saliency degree-related relationships between objects. In this paper we propose a novel Domain Separation Graph Neural Network (DSGNN) which starts with separately extracting the shape and texture cues from each object and builds an shape graph as well as a texture graph for all objects in the given image. Then we propose a Shape-Texture Graph Domain Separation (STGDS) module to separate the task-relevant and irrelevant information of target objects by explicitly modelling the relationship between each pair of objects in terms of their shapes and textures respectively. Furthermore a Cross Image Graph Domain Separation (CIGDS) module is introduced to explore the saliency degree subspace that is robust to different scenes aiming to create a unified representation for targets with the same saliency levels in different images. Importantly our DSGNN automatically learns a multi-dimensional feature to represent each graph edge allowing complex diverse and ranking-related relationships to be modelled. Experimental results show that our DSGNN achieved the new state-of-the-art performance on both ASSR and IRSR datasets with large improvements of 5.2% and 4.1% SA-SOR respectively. Our code is provided in https://github.com/Wu-ZJ/DSGNN.

Out-of-distribution (OOD) detection is essential for deploying machine learning models in open-world environments. Activation-based methods are a key approach in OOD detection working to mitigate overconfident predictions of OOD data. These techniques rectifying anomalous activations enhancing the distinguishability between in-distribution (ID) data and OOD data. However they assume by default that every channel is necessary for OOD detection and rectify anomalous activations in each channel. Empirical evidence has shown that there is a significant difference among various channels in OOD detection and discarding some channels can greatly enhance the performance of OOD detection. Based on this insight we propose \underline D iscriminability-\underline D riven \underline C hannel \underline S election (DDCS) which leverages an adaptive channel selection by estimating the discriminative score of each channel to boost OOD detection. The discriminative score takes inter-class similarity and inter-class variance of training data into account. However the estimation of discriminative score itself is susceptible to anomalous activations. To better estimate score we pre-rectify anomalous activations for each channel mildly. The experimental results show that DDCS achieves state-of-the-art performance on CIFAR and ImageNet-1K benchmarks. Moreover DDCS can generalize to different backbones and OOD scores.

Recently Vision-Language Model (VLM) has greatly advanced the Human-Object Interaction (HOI) detection. The existing VLM-based HOI detectors typically adopt a hand-crafted template (e.g. a photo of a person [action] a/an [object]) to acquire text knowledge through the VLM text encoder. However such approaches only encoding the action-specific text prompts in vocabulary level may suffer from learning ambiguity without exploring the fine-grained clues from the perspective of interaction context. In this paper we propose a novel method to discover Syntactic Interaction Clues for HOI detection (SICHOI) by using VLM. Specifically we first investigate what are the essential elements for an interaction context and then establish a syntactic interaction bank from three levels: spatial relationship action-oriented posture and situational condition. Further to align visual features with the syntactic interaction bank we adopt a multi-view extractor to jointly aggregate visual features from instance interaction and image levels accordingly. In addition we also introduce a dual cross-attention decoder to perform context propagation between text knowledge and visual features thereby enhancing the HOI detection. Experimental results demonstrate that our proposed method achieves state-of-the-art performance on HICO-DET and V-COCO.

Existing Siamese or transformer trackers commonly pose visual object tracking as a one-shot detection problem i.e. locating the target object in a single forward evaluation scheme. Despite the demonstrated success these trackers may easily drift towards distractors with similar appearance due to the single forward evaluation scheme lacking self-correction. To address this issue we cast visual tracking as a point set based denoising diffusion process and propose a novel generative learning based tracker dubbed DiffusionTrack. Our DiffusionTrack possesses two appealing properties: 1) It follows a novel noise-to-target tracking paradigm that leverages multiple denoising diffusion steps to localize the target in a dynamic searching manner per frame. 2) It models the diffusion process using a point set representation which can better handle appearance variations for more precise localization. One side benefit is that DiffusionTrack greatly simplifies the post-processing e.g. removing window penalty scheme. Without bells and whistles our DiffusionTrack achieves leading performance over the state-of-the-art trackers and runs in real-time. The code is in https://github.com/VISION-SJTU/DiffusionTrack.

In Multiple Object Tracking objects often exhibit non-linear motion of acceleration and deceleration with irregular direction changes. Tacking-by-detection (TBD) trackers with Kalman Filter motion prediction work well in pedestrian-dominant scenarios but fall short in complex situations when multiple objects perform non-linear and diverse motion simultaneously. To tackle the complex non-linear motion we propose a real-time diffusion-based MOT approach named DiffMOT. Specifically for the motion predictor component we propose a novel Decoupled Diffusion-based Motion Predictor (D^2MP). It models the entire distribution of various motion presented by the data as a whole. It also predicts an individual object's motion conditioning on an individual's historical motion information. Furthermore it optimizes the diffusion process with much fewer sampling steps. As a MOT tracker the DiffMOT is real-time at 22.7FPS and also outperforms the state-of-the-art on DanceTrack and SportsMOT datasets with 62.3% and 76.2% in HOTA metrics respectively. To the best of our knowledge DiffMOT is the first to introduce a diffusion probabilistic model into the MOT to tackle non-linear motion prediction.