多模态大模型

Video Transformers have become the prevalent solution for various video downstream tasks with superior expressive power and flexibility. However these video transformers suffer from heavy computational costs induced by the massive number of tokens across the entire video frames which has been the major barrier to training the model. Further the patches irrelevant to the main contents e.g. backgrounds degrade the generalization performance of models. To tackle these issues we propose training free token merging for lightweight video Transformer (vid-TLDR) that aims to enhance the efficiency of video Transformers by merging the background tokens without additional training. For vid-TLDR we introduce a novel approach to capture the salient regions in videos only with the attention map. Further we introduce the saliency-aware token merging strategy by dropping the background tokens and sharpening the object scores. Our experiments show that vid-TLDR significantly mitigates the computational complexity of video Transformers while achieving competitive performance compared to the base model without vid-TLDR. Code is available at https://github.com/mlvlab/vid-TLDR.

Zero-shot referring expression comprehension aims at localizing bounding boxes in an image corresponding to provided textual prompts which requires: (i) a fine-grained disentanglement of complex visual scene and textual context and (ii) a capacity to understand relationships among disentangled entities. Unfortunately existing large vision-language alignment (VLA) models e.g. CLIP struggle with both aspects so cannot be directly used for this task. To mitigate this gap we leverage large foundation models to disentangle both images and texts into triplets in the format of (subject predicate object). After that grounding is accomplished by calculating the structural similarity matrix between visual and textual triplets with a VLA model and subsequently propagate it to an instance-level similarity matrix. Furthermore to equip VLA models with the ability of relationship understanding we design a triplet-matching objective to fine-tune the VLA models on a collection of curated dataset containing abundant entity relationships. Experiments demonstrate that our visual grounding performance increase of up to 19.5% over the SOTA zero-shot model on RefCOCO/+/g. On the more challenging Who's Waldo dataset our zero-shot approach achieves comparable accuracy to the fully supervised model. Code is available at https://github.com/Show-han/Zeroshot_REC.

We present Zero-Painter a novel training-free framework for layout-conditional text-to-image synthesis that facilitates the creation of detailed and controlled imagery from textual prompts. Our method utilizes object masks and individual descriptions coupled with a global text prompt to generate images with high fidelity. Zero-Painter employs a two-stage process involving our novel Prompt-Adjusted Cross-Attention (PACA) and Region-Grouped Cross-Attention (ReGCA) blocks ensuring precise alignment of generated objects with textual prompts and mask shapes. Our extensive experiments demonstrate that Zero-Painter surpasses current state-of-the-art methods in preserving textual details and adhering to mask shapes. We will make the codes and the models publicly available.

Recent advances in vision-language models like Stable Diffusion have shown remarkable power in creative image synthesis and editing.However most existing text-to-image editing methods encounter two obstacles: First the text prompt needs to be carefully crafted to achieve good results which is not intuitive or user-friendly. Second they are insensitive to local edits and can irreversibly affect non-edited regions leaving obvious editing traces. To tackle these problems we propose a Zero-shot instructiON-guided local image Editing approach termed ZONE. We first convert the editing intent from the user-provided instruction (e.g. "make his tie blue") into specific image editing regions through InstructPix2Pix. We then propose a Region-IoU scheme for precise image layer extraction from an off-the-shelf segment model. We further develop an edge smoother based on FFT for seamless blending between the layer and the image.Our method allows for arbitrary manipulation of a specific region with a single instruction while preserving the rest. Extensive experiments demonstrate that our ZONE achieves remarkable local editing results and user-friendliness outperforming state-of-the-art methods. Code is available at https://github.com/lsl001006/ZONE.

Recently non-transferable learning (NTL) was proposed to restrict models' generalization toward the target domain(s) which serves as state-of-the-art solutions for intellectual property (IP) protection. However the robustness of the established "transferability barrier" for degrading the target domain performance has not been well studied. In this paper we first show that the generalization performance of NTL models is widely impaired on third-party domains (i.e. the unseen domain in the NTL training stage). We explore the impairment patterns and find that: due to the dominant generalization of non-transferable task NTL models tend to make target-domain-consistent predictions on third-party domains even though only a slight distribution shift from the third-party domain to the source domain. Motivated by these findings we uncover the potential risks of NTL by proposing a simple but effective method (dubbed as TransNTL) to recover the target domain performance with few source domain data. Specifically by performing a group of different perturbations on the few source domain data we obtain diverse third-party domains that evoke the same impairment patterns as the unavailable target domain. Then we fine-tune the NTL model under an impairment-repair self-distillation framework where the source-domain predictions are used to teach the model itself how to predict on third-party domains thus repairing the impaired generalization. Empirically experiments on standard NTL benchmarks show that the proposed TransNTL reaches up to 72% target-domain improvements by using only 10% source domain data. Finally we also explore a feasible defense method and empirically demonstrate its effectiveness.

The landscape of deep learning research is moving towards innovative strategies to harness the true potential of data. Traditionally emphasis has been on scaling model architectures resulting in large and complex neural networks which can be difficult to train with limited computational resources. However independently of the model size data quality (i.e. amount and variability) is still a major factor that affects model generalization. In this work we propose a novel technique to exploit available data through the use of automatic data augmentation for the tasks of image classification and semantic segmentation. We introduce the first Differentiable Augmentation Search method (DAS) to generate variations of images that can be processed as videos. Compared to previous approaches DAS is extremely fast and flexible allowing the search on very large search spaces in less than a GPU day. Our intuition is that the increased receptive field in the temporal dimension provided by DAS could lead to benefits also to the spatial receptive field. More specifically we leverage DAS to guide the reshaping of the spatial receptive field by selecting task-dependant transformations. As a result compared to standard augmentation alternatives we improve in terms of accuracy on ImageNet Cifar10 Cifar100 Tiny-ImageNet Pascal-VOC-2012 and CityScapes datasets when plugging-in our DAS over different light-weight video backbones.

Two primary input modalities prevail in image retrieval: sketch and text. While text is widely used for inter-category retrieval tasks sketches have been established as the sole preferred modality for fine-grained image retrieval due to their ability to capture intricate visual details. In this paper we question the reliance on sketches alone for fine-grained image retrieval by simultaneously exploring the fine-grained representation capabilities of both sketch and text orchestrating a duet between the two. The end result enables precise retrievals previously unattainable allowing users to pose ever-finer queries and incorporate attributes like colour and contextual cues from text. For this purpose we introduce a novel compositionality framework effectively combining sketches and text using pre-trained CLIP models while eliminating the need for extensive fine-grained textual descriptions. Last but not least our system extends to novel applications in composed image retrieval domain attribute transfer and fine-grained generation providing solutions for various real-world scenarios.

The You Only Look Once (YOLO) series of detectors have established themselves as efficient and practical tools. However their reliance on predefined and trained object categories limits their applicability in open scenarios. Addressing this limitation we introduce YOLO-World an innovative approach that enhances YOLO with open-vocabulary detection capabilities through vision-language modeling and pre-training on large-scale datasets. Specifically we propose a new Re-parameterizable Vision-Language Path Aggregation Network (RepVL-PAN) and region-text contrastive loss to facilitate the interaction between visual and linguistic information. Our method excels in detecting a wide range of objects in a zero-shot manner with high efficiency. On the challenging LVIS dataset YOLO-World achieves 35.4 AP with 52.0 FPS on V100 which outperforms many state-of-the-art methods in terms of both accuracy and speed. Furthermore the fine-tuned YOLO-World achieves remarkable performance on several downstream tasks including object detection and open-vocabulary instance segmentation. Code and models are available at https://github.com/AILab-CVC/YOLO-World

We introduce a lightweight and accurate architecture for resource-efficient visual correspondence. Our method dubbed XFeat (Accelerated Features) revisits fundamental design choices in convolutional neural networks for detecting extracting and matching local features. Our new model satisfies a critical need for fast and robust algorithms suitable to resource-limited devices. In particular accurate image matching requires sufficiently large image resolutions -- for this reason we keep the resolution as large as possible while limiting the number of channels in the network. Besides our model is designed to offer the choice of matching at the sparse or semi-dense levels each of which may be more suitable for different downstream applications such as visual navigation and augmented reality. Our model is the first to offer semi-dense matching efficiently leveraging a novel match refinement module that relies on coarse local descriptors. XFeat is versatile and hardware-independent surpassing current deep learning-based local features in speed (up to 5x faster) with comparable or better accuracy proven in pose estimation and visual localization. We showcase it running in real-time on an inexpensive laptop CPU without specialized hardware optimizations. Code and weights are available at verlab.dcc.ufmg.br/descriptors/xfeat_cvpr24.

Lately there has been growing interest in adapting vision-language models (VLMs) to image and third-person video classification due to their success in zero-shot recognition. However the adaptation of these models to egocentric videos has been largely unexplored. To address this gap we propose a simple yet effective cross-modal adaptation framework which we call X-MIC. Using a video adapter our pipeline learns to align frozen text embeddings to each egocentric video directly in the shared embedding space. Our novel adapter architecture retains and improves generalization of the pre-trained VLMs by disentangling learnable temporal modeling and frozen visual encoder. This results in an enhanced alignment of text embeddings to each egocentric video leading to a significant improvement in cross-dataset generalization. We evaluate our approach on the Epic-Kitchens Ego4D and EGTEA datasets for fine-grained cross-dataset action generalization demonstrating the effectiveness of our method.

We introduce WonderJourney a modular framework for perpetual 3D scene generation. Unlike prior work on view generation that focuses on a single type of scenes we start at any user-provided location (by a text description or an image) and generate a journey through a long sequence of diverse yet coherently connected 3D scenes. We leverage an LLM to generate textual descriptions of the scenes in this journey a text-driven point cloud generation pipeline to make a compelling and coherent sequence of 3D scenes and a large VLM to verify the generated scenes. We show compelling diverse visual results across various scene types and styles forming imaginary "wonderjourneys". Project website: https://kovenyu.com/WonderJourney.

We introduce WildlifeMapper (WM) a flexible model designed to detect locate and identify multiple species in aerial imagery. It addresses the limitations of traditional labor-intensive wildlife population assessments that are central to advancing environmental conservation efforts worldwide. While a number of methods exist to automate this process they are often limited in their ability to generalize to different species or landscapes due to the dominance of homogeneous backgrounds and/or poorly captured local image structures. WM introduces two novel modules that help to capture the local structure and context of objects of interest to accurately localize and identify them achieving a state-of-the-art (SOTA) detection rate of 0.56 mAP. Further we introduce a large aerial imagery dataset with more than 11k Images and 28k annotations verified by trained experts. WM also achieves SOTA performance on 3 other publicly available aerial survey datasets collected across 4 different countries improving mAP by 42%. Source code and trained models are available at Github

3D-aware Generative Adversarial Networks (GANs) have shown remarkable progress in learning to generate multi-view-consistent images and 3D geometries of scenes from collections of 2D images via neural volume rendering. Yet the significant memory and computational costs of dense sampling in volume rendering have forced 3D GANs to adopt patch-based training or employ low-resolution rendering with post-processing 2D super resolution which sacrifices multiview consistency and the quality of resolved geometry. Consequently 3D GANs have not yet been able to fully resolve the rich 3D geometry present in 2D images. In this work we propose techniques to scale neural volume rendering to the much higher resolution of native 2D images thereby resolving fine-grained 3D geometry with unprecedented detail. Our approach employs learning-based samplers for accelerating neural rendering for 3D GAN training using up to 5 times fewer depth samples. This enables us to explicitly "render every pixel" of the full-resolution image during training and inference without post-processing superresolution in 2D. Together with our strategy to learn high-quality surface geometry our method synthesizes high-resolution 3D geometry and strictly view-consistent images while maintaining image quality on par with baselines relying on post-processing super resolution. We demonstrate state-of-the-art 3D gemetric quality on FFHQ and AFHQ setting a new standard for unsupervised learning of 3D shapes in 3D GANs.

In this paper we explore the unique modality of sketch for explainability emphasising the profound impact of human strokes compared to conventional pixel-oriented studies. Beyond explanations of network behavior we discern the genuine implications of explainability across diverse downstream sketch-related tasks. We propose a lightweight and portable explainability solution -- a seamless plugin that integrates effortlessly with any pre-trained model eliminating the need for re-training. Demonstrating its adaptability we present four applications: highly studied retrieval and generation and completely novel assisted drawing and sketch adversarial attacks. The centrepiece to our solution is a stroke-level attribution map that takes different forms when linked with downstream tasks. By addressing the inherent non-differentiability of rasterisation we enable explanations at both coarse stroke level (SLA) and partial stroke level (P-SLA) each with its advantages for specific downstream tasks.

Counterfactual reasoning a fundamental aspect of human cognition involves contemplating alternatives to established facts or past events significantly enhancing our abilities in planning and decision-making. In light of the advancements in current multi-modal large language models we explore their effectiveness in counterfactual reasoning. To facilitate this investigation we introduce a novel dataset C-VQA specifically designed to examine the counterfactual reasoning capabilities of modern multi-modal large language models. This dataset is constructed by infusing original questions with counterfactual presuppositions spanning various types such as numerical and boolean queries. It encompasses a mix of real and synthetic data representing a wide range of difficulty levels. Our thorough evaluations of contemporary vision-language models using this dataset have revealed substantial performance drops with some models showing up to a 40% decrease highlighting a significant gap between current models and human-like vision reasoning capabilities. We hope our dataset will serve as a vital benchmark for evaluating the counterfactual reasoning capabilities of models. Code and dataset are publicly available at https://bzhao.me/C-VQA/.

Driver's eye gaze holds a wealth of cognitive and intentional cues crucial for intelligent vehicles. Despite its significance research on in-vehicle gaze estimation remains limited due to the scarcity of comprehensive and well-annotated datasets in real driving scenarios. In this paper we present three novel elements to advance in-vehicle gaze research. Firstly we introduce IVGaze a pioneering dataset capturing in-vehicle gaze collected from 125 individuals and covering a large range of gaze and head within vehicles. Conventional gaze collection systems are inadequate for in-vehicle use. In this dataset we propose a new vision-based solution for in-vehicle gaze collection introducing a refined gaze target calibration method to tackle annotation challenges. Second our research focuses on in-vehicle gaze estimation leveraging the IVGaze. Images of in-vehicle faces often suffer from low resolution prompting our introduction of a gaze pyramid transformer that harnesses transformer-based multilevel features integration. Expanding upon this we introduce the dual-stream gaze pyramid transformer (GazeDPTR). Employing perspective transformation we rotate virtual cameras to normalize images utilizing camera pose to merge normalized and original images for accurate gaze estimation. GazeDPTR showcases state-of-the-art performance on the IVGaze dataset. Thirdly we explore a novel strategy for gaze zone classification by extending the GazeDPTR. A foundational tri-plane and project gaze onto these planes are newly defined. Leveraging both positional features from the projection points and visual attributes from images we achieve superior performance compared to relying solely on visual features thereby substantiating the advantage of gaze estimation. The project is available at https://yihua.zone/work/ivgaze

Visible-infrared (RGB-IR) image fusion has shown great potentials in object detection based on unmanned aerial vehicles (UAVs). However the weakly misalignment problem between multimodal image pairs limits its performance in object detection. Most existing methods often ignore the modality gap and emphasize a strict alignment resulting in an upper bound of alignment quality and an increase of implementation costs. To address these challenges we propose a novel method named Offset-guided Adaptive Feature Alignment (OAFA) which could adaptively adjust the relative positions between multimodal features. Considering the impact of modality gap on the cross-modality spatial matching a Cross-modality Spatial Offset Modeling (CSOM) module is designed to establish a common subspace to estimate the precise feature-level offsets. Then an Offset-guided Deformable Alignment and Fusion (ODAF) module is utilized to implicitly capture optimal fusion positions for detection task rather than conducting a strict alignment. Comprehensive experiments demonstrate that our method not only achieves state-of-the-art performance in the UAVs-based object detection task but also shows strong robustness to the weakly misalignment problem.

Recent advancements in neural networks have showcased their remarkable capabilities across various domains. Despite these successes the "black box" problem still remains. To address this we propose a novel framework WWW that offers the 'what' 'where' and 'why' of the neural network decisions in human-understandable terms. Specifically WWW utilizes an adaptive selection for concept discovery employing adaptive cosine similarity and thresholding techniques to effectively explain 'what'. To address the 'where' and 'why' we proposed a novel combination of neuron activation maps (NAMs) with Shapley values generating localized concept maps and heatmaps for individual inputs. Furthermore WWW introduces a method for predicting uncertainty leveraging heatmap similarities to estimate the prediction's reliability. Experimental evaluations of WWW demonstrate superior performance in both quantitative and qualitative metrics outperforming existing methods in interpretability. WWW provides a unified solution for explaining 'what' 'where' and 'why' introducing a method for localized explanations from global interpretations and offering a plug-and-play solution adaptable to various architectures. The code is available at: https://github.com/ailab-kyunghee/WWW

Vision-language navigation (VLN) requires an agent to navigate through an 3D environment based on visual observations and natural language instructions. It is clear that the pivotal factor for successful navigation lies in the comprehensive scene understanding. Previous VLN agents employ monocular frameworks to extract 2D features of perspective views directly. Though straightforward they struggle for capturing 3D geometry and semantics leading to a partial and incomplete environment representation. To achieve a comprehensive 3D representation with fine-grained details we introduce a Volumetric Environment Representation (VER) which voxelizes the physical world into structured 3D cells. For each cell VER aggregates multi-view 2D features into such a unified 3D space via 2D-3D sampling. Through coarse-to-fine feature extraction and multi-task learning for VER our agent predicts 3D occupancy 3D room layout and 3D bounding boxes jointly. Based on online collected VERs our agent performs volume state estimation and builds episodic memory for predicting the next step. Experimental results show our environment representations from multi-task learning lead to evident performance gains on VLN. Our model achieves state-of-the-art performance across VLN benchmarks (R2R REVERIE and R4R).

Self-Supervised Learning (SSL) has demonstrated promising results in 3D medical image analysis. However the lack of high-level semantics in pre-training still heavily hinders the performance of downstream tasks. We observe that 3D medical images contain relatively consistent contextual position information i.e. consistent geometric relations between different organs which leads to a potential way for us to learn consistent semantic representations in pre-training. In this paper we propose a simple-yet-effective Volume Contrast (VoCo) framework to leverage the contextual position priors for pre-training. Specifically we first generate a group of base crops from different regions while enforcing feature discrepancy among them where we employ them as class assignments of different regions. Then we randomly crop sub-volumes and predict them belonging to which class (located at which region) by contrasting their similarity to different base crops which can be seen as predicting contextual positions of different sub-volumes. Through this pretext task VoCo implicitly encodes the contextual position priors into model representations without the guidance of annotations enabling us to effectively improve the performance of downstream tasks that require high-level semantics. Extensive experimental results on six downstream tasks demonstrate the superior effectiveness of VoCo. Code will be available at https://github.com/Luffy03/VoCo.