CVPR 2024 论文列表

Distribution shift widely exists in medical images acquired from different medical centres and poses a significant obstacle to deploying the pre-trained semantic segmentation model in real-world applications. Test-time adaptation has proven its effectiveness in tackling the cross-domain distribution shift during inference. However most existing methods achieve adaptation by updating the pre-trained models rendering them susceptible to error accumulation and catastrophic forgetting when encountering a series of distribution shifts (i.e. under the continual test-time adaptation setup). To overcome these challenges caused by updating the models in this paper we freeze the pre-trained model and propose the Visual Prompt-based Test-Time Adaptation (VPTTA) method to train a specific prompt for each test image to align the statistics in the batch normalization layers. Specifically we present the low-frequency prompt which is lightweight with only a few parameters and can be effectively trained in a single iteration. To enhance prompt initialization we equip VPTTA with a memory bank to benefit the current prompt from previous ones. Additionally we design a warm-up mechanism which mixes source and target statistics to construct warm-up statistics thereby facilitating the training process. Extensive experiments demonstrate the superiority of our VPTTA over other state-of-the-art methods on two medical image segmentation benchmark tasks. The code and weights of pre-trained source models are available at https://github.com/Chen-Ziyang/VPTTA.

Point cloud analysis has achieved outstanding performance by transferring point cloud pre-trained models. However existing methods for model adaptation usually update all model parameters i.e. full fine-tuning paradigm which is inefficient as it relies on high computational costs (e.g. training GPU memory) and massive storage space. In this paper we aim to study parameter-efficient transfer learning for point cloud analysis with an ideal trade-off between task performance and parameter efficiency. To achieve this goal we freeze the parameters of the default pre-trained models and then propose the Dynamic Adapter which generates a dynamic scale for each token considering the token significance to the downstream task. We further seamlessly integrate Dynamic Adapter with Prompt Tuning (DAPT) by constructing Internal Prompts capturing the instance-specific features for interaction. Extensive experiments conducted on five challenging datasets demonstrate that the proposed DAPT achieves superior performance compared to the full fine-tuning counterparts while significantly reducing the trainable parameters and training GPU memory by 95% and 35% respectively. Code is available at https://github.com/LMD0311/DAPT.

Adapting driving behavior to new environments customs and laws is a long-standing problem in autonomous driving precluding the widespread deployment of autonomous vehicles (AVs). In this paper we present LLaDA a simple yet powerful tool that enables human drivers and autonomous vehicles alike to drive everywhere by adapting their tasks and motion plans to traffic rules in new locations. LLaDA achieves this by leveraging the impressive zero-shot generalizability of large language models (LLMs) in interpreting the traffic rules in the local driver handbook. Through an extensive user study we show that LLaDA's instructions are useful in disambiguating in-the-wild unexpected situations. We also demonstrate LLaDA's ability to adapt AV motion planning policies in real-world datasets; LLaDA outperforms baseline planning approaches on all our metrics. Please check our website for more details: https://boyiliee.github.io/llada.

In this paper we look at cross-domain few-shot classification which presents the challenging task of learning new classes in previously unseen domains with few labelled examples. Existing methods though somewhat effective encounter several limitations which we alleviate through two significant improvements. First we introduce a lightweight parameter-efficient adaptation strategy to address overfitting associated with fine-tuning a large number of parameters on small datasets. This strategy employs a linear transformation of pre-trained features significantly reducing the trainable parameter count. Second we replace the traditional nearest centroid classifier with a discriminative sample-aware loss function enhancing the model's sensitivity to the inter- and intra-class variances within the training set for improved clustering in feature space. Empirical evaluations on the Meta-Dataset benchmark showcase that our approach not only improves accuracy up to 7.7% and 5.3% on previously seen and unseen datasets respectively but also achieves the above performance while being at least 3x more parameter-efficient than existing methods establishing a new state-of-the-art in cross-domain few-shot learning. Our code is available at https://github.com/rashindrie/DIPA.

Source-free domain adaptation (SFDA) assumes that model adaptation only accesses the well-learned source model and unlabeled target instances for knowledge transfer. However cross-domain distribution shift easily triggers invalid discriminative semantics from source model on recognizing the target samples. Hence understanding the specific content of discriminative pattern and adjusting their representation in target domain become the important key to overcome SFDA. To achieve such a vision this paper proposes a novel explanation paradigm "Discriminative Pattern Calibration (DPC)" mechanism on solving SFDA issue. Concretely DPC first utilizes learning network to infer the discriminative regions on the target images and specifically emphasizes them in feature space to enhance their representation. Moreover DPC relies on the attention-reversed mixup mechanism to augment more samples and improve the robustness of the classifier. Considerable experimental results and studies suggest that the effectiveness of our DPC in enhancing the performance of existing SFDA baselines.

Micro-mesh (u-mesh) is a new graphics primitive for compact representation of extreme geometry consisting of a low-polygon base mesh enriched by per micro-vertex displacement. A new generation of GPUs supports this structure with hardware evolution on u-mesh ray tracing achieving real-time rendering in pixel level geometric details. In this article we present a differentiable framework to convert standard meshes into this efficient format offering a holistic scheme in contrast to the previous stage-based methods. In our construction context a u-mesh is defined where each base triangle is a parametric primitive which is then reparameterized with Laplacian operators for efficient geometry optimization. Our framework offers numerous advantages for high-quality u-mesh production: (i) end-to-end geometry optimization and displacement baking; (ii) enabling the differentiation of renderings with respect to umesh for faithful reprojectability; (iii) high scalability for integrating useful features for u-mesh production and rendering such as minimizing shell volume maintaining the isotropy of the base mesh and visual-guided adaptive level of detail. Extensive experiments on u-mesh construction for a large set of high-resolution meshes demonstrate the superior quality achieved by the proposed scheme.

Diffusion models trained on large-scale datasets have achieved remarkable progress in image synthesis. However due to the randomness in the diffusion process they often struggle with handling diverse low-level tasks that require details preservation. To overcome this limitation we present a new Diff-Plugin framework to enable a single pre-trained diffusion model to generate high-fidelity results across a variety of low-level tasks. Specifically we first propose a lightweight Task-Plugin module with a dual branch design to provide task-specific priors guiding the diffusion process in preserving image content. We then propose a Plugin-Selector that can automatically select different Task-Plugins based on the text instruction allowing users to edit images by indicating multiple low-level tasks with natural language. We conduct extensive experiments on 8 low-level vision tasks. The results demonstrate the superiority of Diff-Plugin over existing methods particularly in real-world scenarios. Our ablations further validate that Diff-Plugin is stable schedulable and supports robust training across different dataset sizes.

To insert Trojan into a Deep Neural Network (DNN) the existing attack assumes the attacker can access the victim's training facilities. However a realistic threat model was recently developed by leveraging memory fault to inject Trojans at the inference stage. In this work we develop a novel Trojan attack by adopting a unique memory fault injection technique that can inject bit-flip into the page table of the main memory. In the main memory each weight block consists of a group of weights located at a specific address of a DRAM row. A bit-flip in the page frame number replaces a target weight block of a DNN model with another replacement weight block. To develop a successful Trojan attack leveraging this unique fault model the attacker must solve three key challenges: i) how to identify a minimum set of target weight blocks to be modified? ii) how to identify the corresponding optimal replacement weight block? iii) how to optimize the trigger to maximize the attacker's objective given a target and replacement weight block set? We address them by proposing a novel Deep-TROJ attack algorithm that can identify a minimum set of vulnerable target and corresponding replacement weight blocks while optimizing the trigger at the same time. We evaluate the performance of our proposed Deep-TROJ on CIFAR-10 CIFAR-100 and ImageNet dataset for sixteen different DNN architectures including vision transformers. Proposed Deep-TROJ is the most successful one to date that does not require access to training facilities while successfully bypassing the existing defenses. Our code is available at https://github.com/ML-Security-Research-LAB/Deep-TROJ.

Quantization for model compression can efficiently reduce the network complexity and storage requirement but the original training data is necessary to remedy the performance loss caused by quantization. The Data-Free Quantization (DFQ) methods have been proposed to handle the absence of original training data with synthetic data. However there are differences between the synthetic and original training data which affects the performance of the quantized network but none of the existing methods considers the differences. In this paper we propose an efficient data-free quantization via pseudo-label filtering which is the first to evaluate the synthetic data before quantization. We design a new metric for evaluating synthetic data using self-entropy which indicates the reliability of synthetic data. The synthetic data can be categorized with the metric into high- and low-reliable datasets for the following training process. Besides the multiple pseudo-labels are designed to label the synthetic data with different reliability which can provide valuable supervision information and avoid misleading training by low-reliable samples. Extensive experiments are implemented on several datasets including CIFAR-10 CIFAR-100 and ImageNet with various models. The experimental results show that our method can perform excellently and outperform existing methods in accuracy.

The diffusion-based text-to-image model harbors immense potential in transferring reference style. However current encoder-based approaches significantly impair the text controllability of text-to-image models while transferring styles. In this paper we introduce DEADiff to address this issue using the following two strategies: 1) a mechanism to decouple the style and semantics of reference images. The decoupled feature representations are first extracted by Q-Formers which are instructed by different text descriptions. Then they are injected into mutually exclusive subsets of cross-attention layers for better disentanglement. 2) A non-reconstructive learning method. The Q-Formers are trained using paired images rather than the identical target in which the reference image and the ground-truth image are with the same style or semantics. We show that DEADiff attains the best visual stylization results and optimal balance between the text controllability inherent in the text-to-image model and style similarity to the reference image as demonstrated both quantitatively and qualitatively. Our project page is https://tianhao-qi.github.io/DEADiff/.

Low-shot counters estimate the number of objects corresponding to a selected category based on only few or no exemplars annotated in the image. The current state-of-the-art estimates the total counts as the sum over the object location density map but do not provide object locations and sizes which are crucial for many applications. This is addressed by detection-based counters which however fall behind in the total count accuracy. Furthermore both approaches tend to overestimate the counts in the presence of other object classes due to many false positives. We propose DAVE a low-shot counter based on a detect-and-verify paradigm that avoids the aforementioned issues by first generating a high-recall detection set and then verifying the detections to identify and remove the outliers.This jointly increases the recall and precision leading to accurate counts. DAVE outperforms the top density-based counters by ?20% in the total count MAE it outperforms the most recent detection-based counter by ?20% in detection quality and sets a new state-of-the-art in zero-shot as well as text-prompt-based counting.

This paper presents a novel non-rigid point set registration method that is inspired by unsupervised clustering analysis. Unlike previous approaches that treat the source and target point sets as separate entities we develop a holistic framework where they are formulated as clustering centroids and clustering members separately. We then adopt Tikhonov regularization with an ?1-induced Laplacian kernel instead of the commonly used Gaussian kernel to ensure smooth and more robust displacement fields. Our formulation delivers closed-form solutions theoretical guarantees independence from dimensions and the ability to handle large deformations. Subsequently we introduce a clustering-improved Nystrom method to effectively reduce the computational complexity and storage of the Gram matrix to linear while providing a rigorous bound for the low rank approximation. Our method achieves high accuracy results across various scenarios and surpasses competitors by a significant margin particularly on shapes with substantial deformations. Additionally we demonstrate the versatility of our method in challenging tasks such as shape transfer and medical registration.

Continual Test-Time Adaptation (CTTA) is proposed to migrate a source pre-trained model to continually changing target distributions addressing real-world dynamism. Existing CTTA methods mainly rely on entropy minimization or teacher-student pseudo-labeling schemes for knowledge extraction in unlabeled target domains. However dynamic data distributions cause miscalibrated predictions and noisy pseudo-labels in existing self-supervised learning methods hindering the effective mitigation of error accumulation and catastrophic forgetting problems during the continual adaptation process. To tackle these issues we propose a continual self-supervised method Adaptive Distribution Masked Autoencoders (ADMA) which enhances the extraction of target domain knowledge while mitigating the accumulation of distribution shifts. Specifically we propose a Distribution-aware Masking (DaM) mechanism to adaptively sample masked positions followed by establishing consistency constraints between the masked target samples and the original target samples. Additionally for masked tokens we utilize an efficient decoder to reconstruct a hand-crafted feature descriptor (e.g. Histograms of Oriented Gradients) leveraging its invariant properties to boost task-relevant representations. Through conducting extensive experiments on four widely recognized benchmarks our proposed method attains state-of-the-art performance in both classification and segmentation CTTA tasks.

Image Quality Assessment (IQA) constitutes a fundamental task within the field of computer vision yet it remains an unresolved challenge owing to the intricate distortion conditions diverse image contents and limited availability of data. Recently the community has witnessed the emergence of numerous large-scale pretrained foundation models. However it remains an open problem whether the scaling law in high-level tasks is also applicable to IQA tasks which are closely related to low-level clues. In this paper we demonstrate that with a proper injection of local distortion features a larger pretrained vision transformer (ViT) foundation model performs better in IQA tasks. Specifically for the lack of local distortion structure and inductive bias of the large-scale pretrained ViT we use another pretrained convolution neural networks (CNNs) which is well known for capturing the local structure to extract multi-scale image features. Further we propose a local distortion extractor to obtain local distortion features from the pretrained CNNs and a local distortion injector to inject the local distortion features into ViT. By only training the extractor and injector our method can benefit from the rich knowledge in the powerful foundation models and achieve state-of-the-art performance on popular IQA datasets indicating that IQA is not only a low-level problem but also benefits from stronger high-level features drawn from large-scale pretrained models. Codes are publicly available at: https://github.com/NeosXu/LoDa.

Recently deep neural networks have achieved excellent performance on low-light raw video enhancement. However they often come with high computational complexity and large memory costs which hinder their applications on resource-limited devices. In this paper we explore the feasibility of applying the extremely compact binary neural network (BNN) to low-light raw video enhancement. Nevertheless there are two main issues with binarizing video enhancement models. One is how to fuse the temporal information to improve low-light denoising without complex modules. The other is how to narrow the performance gap between binary convolutions with the full precision ones. To address the first issue we introduce a spatial-temporal shift operation which is easy-to-binarize and effective. The temporal shift efficiently aggregates the features of neighbor frames and the spatial shift handles the misalignment caused by the large motion in videos. For the second issue we present a distribution-aware binary convolution which captures the distribution characteristics of real-valued input and incorporates them into plain binary convolutions to alleviate the degradation in performance. Extensive quantitative and qualitative experiments have shown our high-efficiency binarized low-light raw video enhancement method can attain a promising performance. The code is available at https://github.com/ying-fu/BRVE.

Low-shot image classification is a fundamental task in computer vision and the emergence of large-scale vision-language models such as CLIP has greatly advanced the forefront of research in this field. However most existing CLIP-based methods lack the flexibility to effectively incorporate other pre-trained models that encompass knowledge distinct from CLIP. To bridge the gap this work proposes a simple and effective probabilistic model ensemble framework based on Gaussian processes which have previously demonstrated remarkable efficacy in processing small data. We achieve the integration of prior knowledge by specifying the mean function with CLIP and the kernel function with an ensemble of deep kernels built upon various pre-trained models. By regressing the classification label directly our framework enables analytical inference straightforward uncertainty quantification and principled hyper-parameter tuning. Through extensive experiments on standard benchmarks we demonstrate that our method consistently outperforms competitive ensemble baselines regarding predictive performance. Additionally we assess the robustness of our method and the quality of the yielded uncertainty estimates on out-of-distribution datasets. We also illustrate that our method despite relying on label regression still enjoys superior model calibration compared to most deterministic baselines.

Diffusion models (DMs) have exhibited superior performance in generating high-quality and diverse images. However this exceptional performance comes at the cost of expensive generation process particularly due to the heavily used attention module in leading models. Existing works mainly adopt a retraining process to enhance DM efficiency. This is computationally expensive and not very scalable. To this end we introduce the Attention-driven Training-free Efficient Diffusion Model (AT-EDM) framework that leverages attention maps to perform run-time pruning of redundant tokens without the need for any retraining. Specifically for single-denoising-step pruning we develop a novel ranking algorithm Generalized Weighted Page Rank (G-WPR) to identify redundant tokens and a similarity-based recovery method to restore tokens for the convolution operation. In addition we propose a Denoising-Steps-Aware Pruning (DSAP) approach to adjust the pruning budget across different denoising timesteps for better generation quality. Extensive evaluations show that AT-EDM performs favorably against prior art in terms of efficiency (e.g. 38.8% FLOPs saving and up to 1.53x speed-up over Stable Diffusion XL) while maintaining nearly the same FID and CLIP scores as the full model.

This work introduces ArtAdapter a transformative text-to-image (T2I) style transfer framework that transcends traditional limitations of color brushstrokes and object shape capturing high-level style elements such as composition and distinctive artistic expression. The integration of a multi-level style encoder with our proposed explicit adaptation mechanism enables ArtAdapter to achieve unprecedented fidelity in style transfer ensuring close alignment with textual descriptions. Additionally the incorporation of an Auxiliary Content Adapter (ACA) effectively separates content from style alleviating the borrowing of content from style references. Moreover our novel fast finetuning approach could further enhance zero-shot style representation while mitigating the risk of overfitting. Comprehensive evaluations confirm that ArtAdapter surpasses current state-of-the-art methods.