CVPR2024/CVPR2024-papers-abstract-index huggingface dataset:
Vision-centric autonomous driving has recently raised wide attention due to its lower cost. Pre-training is essential for extracting a universal representation. However current vision-centric pre-training typically relies on either 2D or 3D pre-text tasks overlooking the temporal characteristics of autonomous driving as a 4D scene understanding task. In this paper we address this challenge by introducing a world model-based autonomous driving 4D representation learning framework dubbed DriveWorld which is capable of pre-training from multi-camera driving videos in a spatio-temporal fashion. Specifically we propose a Memory State-Space Model for spatio-temporal modelling which consists of a Dynamic Memory Bank module for learning temporal-aware latent dynamics to predict future changes and a Static Scene Propagation module for learning spatial-aware latent statics to offer comprehensive scene contexts. We additionally introduce a Task Prompt to decouple task-aware features for various downstream tasks. The experiments demonstrate that DriveWorld delivers promising results on various autonomous driving tasks.
We additionally introduce a Task Prompt to decouple task-aware features for various downstream tasks. The experiments demonstrate that DriveWorld delivers promising results on various autonomous driving tasks. When pre-trained with the OpenScene dataset DriveWorld achieves a 7.5% increase in mAP for 3D object detection a 3.0% increase in IoU for online mapping a 5.0% increase in AMOTA for multi-object tracking a 0.1m decrease in minADE for motion forecasting a 3.0% increase in IoU for occupancy prediction and a 0.34m reduction in average L2 error for planning.
Modularity plays a crucial role in the development and maintenance of complex systems. While end-to-end text spotting efficiently mitigates the issues of error accumulation and sub-optimal performance seen in traditional two-step methodologies the two-step methods continue to be favored in many competitions and practical settings due to their superior modularity. In this paper we introduce Bridging Text Spotting a novel approach that resolves the error accumulation and suboptimal performance issues in two-step methods while retaining modularity. To achieve this we adopt a well-trained detector and recognizer that are developed and trained independently and then lock their parameters to preserve their already acquired capabilities. Subsequently we introduce a Bridge that connects the locked detector and recognizer through a zero-initialized neural network. This zero-initialized neural network initialized with weights set to zeros ensures seamless integration of the large receptive field features in detection into the locked recognizer. Furthermore since the fixed detector and recognizer cannot naturally acquire end-to-end optimization features we adopt the Adapter to facilitate their efficient learning of these features.
This zero-initialized neural network initialized with weights set to zeros ensures seamless integration of the large receptive field features in detection into the locked recognizer. Furthermore since the fixed detector and recognizer cannot naturally acquire end-to-end optimization features we adopt the Adapter to facilitate their efficient learning of these features. We demonstrate the effectiveness of the proposed method through extensive experiments: Connecting the latest detector and recognizer through Bridging Text Spotting we achieved an accuracy of 83.3% on Total-Text 69.8% on CTW1500 and 89.5% on ICDAR 2015. The code is available at https://github.com/mxin262/Bridging-Text-Spotting.
We present TokenCompose a Latent Diffusion Model for text-to-image generation that achieves enhanced consistency between user-specified text prompts and model-generated images. Despite its tremendous success the standard denoising process in the Latent Diffusion Model takes text prompts as conditions only absent explicit constraint for the consistency between the text prompts and the image contents leading to unsatisfactory results for composing multiple object categories. Our proposed TokenCompose aims to improve multi-category instance composition by introducing the token-wise consistency terms between the image content and object segmentation maps in the finetuning stage. TokenCompose can be applied directly to the existing training pipeline of text-conditioned diffusion models without extra human labeling information. By finetuning Stable Diffusion with our approach the model exhibits significant improvements in multi-category instance composition and enhanced photorealism for its generated images.
Learning generalizable visual representations from Internet data has yielded promising results for robotics. Yet prevailing approaches focus on pre-training 2D representations being sub-optimal to deal with occlusions and accurately localize objects in complex 3D scenes. Meanwhile 3D representation learning has been limited to single-object understanding. To address these limitations we introduce a novel 3D pre-training framework for robotics named SUGAR that captures semantic geometric and affordance properties of objects through 3D point clouds. We underscore the importance of cluttered scenes in 3D representation learning and automatically construct a multi-object dataset benefiting from cost-free supervision in simulation. SUGAR employs a versatile transformer-based model to jointly address five pre-training tasks namely cross-modal knowledge distillation for semantic learning masked point modeling to understand geometry structures grasping pose synthesis for object affordance 3D instance segmentation and referring expression grounding to analyze cluttered scenes. We evaluate our learned representation on three robotic-related tasks namely zero-shot 3D object recognition referring expression grounding and language-driven robotic manipulation. Experimental results show that SUGAR's 3D representation outperforms state-of-the-art 2D and 3D representations.
Photorealistic simulation plays a crucial role in applications such as autonomous driving where advances in neural radiance fields (NeRFs) may allow better scalability through the automatic creation of digital 3D assets. However reconstruction quality suffers on street scenes due to largely collinear camera motions and sparser samplings at higher speeds. On the other hand the application often demands rendering from camera views that deviate from the inputs to accurately simulate behaviors like lane changes. In this paper we propose several insights that allow a better utilization of Lidar data to improve NeRF quality on street scenes. First our framework learns a geometric scene representation from Lidar which are fused with the implicit grid-based representation for radiance decoding thereby supplying stronger geometric information offered by explicit point cloud. Second we put forth a robust occlusion-aware depth supervision scheme which allows utilizing densified Lidar points by accumulation. Third we generate augmented training views from Lidar points for further improvement. Our insights translate to largely improved novel view synthesis under real driving scenes.
Current vision-language pre-training (VLP) methodologies predominantly depend on paired image-text datasets a resource that is challenging to acquire in radiology due to privacy considerations and labelling complexities. Data augmentation provides a practical solution to overcome the issue of data scarcity however most augmentation methods exhibit a limited focus prioritising either image or text augmentation exclusively. Acknowledging this limitation our objective is to devise a framework capable of concurrently augmenting medical image and text data. We design a Pairwise Augmentation (PairAug) approach that contains an Inter-patient Augmentation (InterAug) branch and an Intra-patient Augmentation (IntraAug) branch. Specifically the InterAug branch of our approach generates radiology images using synthesised yet plausible reports derived from a Large Language Model (LLM). The generated pairs can be considered a collection of new patient cases since they are artificially created and may not exist in the original dataset. In contrast the IntraAug branch uses newly generated reports to manipulate images. This process allows us to create new paired data for each individual with diverse medical conditions.
The generated pairs can be considered a collection of new patient cases since they are artificially created and may not exist in the original dataset. In contrast the IntraAug branch uses newly generated reports to manipulate images. This process allows us to create new paired data for each individual with diverse medical conditions. Our extensive experiments on various downstream tasks covering medical image classification zero-shot and fine-tuning analysis demonstrate that our PairAug concurrently expanding both image and text data substantially outperforms image-/text-only expansion baselines and advanced medical VLP baselines. Our code is released at https://github.com/YtongXie/PairAug.
Implicit Neural Representation (INR) which utilizes a neural network to map coordinate inputs to corresponding attributes is causing a revolution in the field of signal processing. However current INR techniques suffer from a restricted capability to tune their supported frequency set resulting in imperfect performance when representing complex signals with multiple frequencies. We have identified that this frequency-related problem can be greatly alleviated by introducing variable-periodic activation functions for which we propose FINER. By initializing the bias of the neural network within different ranges sub-functions with various frequencies in the variable-periodic function are selected for activation. Consequently the supported frequency set of FINER can be flexibly tuned leading to improved performance in signal representation. We demonstrate the capabilities of FINER in the contexts of 2D image fitting 3D signed distance field representation and 5D neural radiance fields optimization and we show that it outperforms existing INRs.
Video anomaly detection (VAD) aims to temporally locate abnormal events in a video. Existing works mostly rely on training deep models to learn the distribution of normality with either video-level supervision one-class supervision or in an unsupervised setting. Training-based methods are prone to be domain-specific thus being costly for practical deployment as any domain change will involve data collection and model training. In this paper we radically depart from previous efforts and propose LAnguage-based VAD (LAVAD) a method tackling VAD in a novel training-free paradigm exploiting the capabilities of pre-trained large language models (LLMs) and existing vision-language models (VLMs). We leverage VLM-based captioning models to generate textual descriptions for each frame of any test video. With the textual scene description we then devise a prompting mechanism to unlock the capability of LLMs in terms of temporal aggregation and anomaly score estimation turning LLMs into an effective video anomaly detector. We further leverage modality-aligned VLMs and propose effective techniques based on cross-modal similarity for cleaning noisy captions and refining the LLM-based anomaly scores.
We further leverage modality-aligned VLMs and propose effective techniques based on cross-modal similarity for cleaning noisy captions and refining the LLM-based anomaly scores. We evaluate LAVAD on two large datasets featuring real-world surveillance scenarios (UCF-Crime and XD-Violence) showing that it outperforms both unsupervised and one-class methods without requiring any training or data collection.
Diffusion-based text-to-image generative models e.g. Stable Diffusion have revolutionized the field of content generation enabling significant advancements in areas like image editing and video synthesis. Despite their formidable capabilities these models are not without their limitations. It is still challenging to synthesize an image that aligns well with the input text and multiple runs with carefully crafted prompts are required to achieve satisfactory results. To mitigate these limitations numerous studies have endeavored to fine-tune the pre-trained diffusion models i.e.. UNet utilizing various technologies. Yet amidst these efforts a pivotal question of text-to-image diffusion model training has remained largely unexplored: Is it possible and feasible to fine-tune the text encoder to improve the performance of text-to-image diffusion models? Our findings reveal that instead of replacing the CLIP text encoder used in Stable Diffusion with other large language models we can enhance it through our proposed fine-tuning approach TextCraftor leading to substantial improvements in quantitative benchmarks and human assessments. Interestingly our technique also empowers controllable image generation through the interpolation of different text encoders fine-tuned with various rewards. We also demonstrate that TextCraftor is orthogonal to UNet finetuning and can be combined to further improve generative quality.
Existing action quality assessment (AQA) methods mainly learn deep representations at the video level for scoring diverse actions. Due to the lack of a fine-grained understanding of actions in videos they harshly suffer from low credibility and interpretability thus insufficient for stringent applications such as Olympic diving events. We argue that a fine-grained understanding of actions requires the model to perceive and parse actions in both time and space which is also the key to the credibility and interpretability of the AQA technique. Based on this insight we propose a new fine-grained spatial-temporal action parser named FineParser. It learns human-centric foreground action representations by focusing on target action regions within each frame and exploiting their fine-grained alignments in time and space to minimize the impact of invalid backgrounds during the assessment. In addition we construct fine-grained annotations of human-centric foreground action masks for the FineDiving dataset called FineDiving-HM. With refined annotations on diverse target action procedures FineDiving-HM can promote the development of real-world AQA systems. Through extensive experiments we demonstrate the effectiveness of FineParser which outperforms state-of-the-art methods while supporting more tasks of fine-grained action understanding.
With refined annotations on diverse target action procedures FineDiving-HM can promote the development of real-world AQA systems. Through extensive experiments we demonstrate the effectiveness of FineParser which outperforms state-of-the-art methods while supporting more tasks of fine-grained action understanding. Data and code are available at https://github.com/PKU-ICST-MIPL/FineParser_CVPR2024.
The creation of new datasets often presents new challenges for video recognition and can inspire novel ideas while addressing these challenges. While existing datasets mainly comprise landscape mode videos our paper seeks to introduce portrait mode videos to the research community and highlight the unique challenges associated with this video format. With the growing popularity of smartphones and social media applications recognizing portrait mode videos is becoming increasingly important. To this end we have developed the first dataset dedicated to portrait mode video recognition namely PortraitMode-400. The taxonomy of PortraitMode-400 was constructed in a data-driven manner comprising 400 fine-grained categories and rigorous quality assurance was implemented to ensure the accuracy of human annotations. In addition to the new dataset we conducted a comprehensive analysis of the impact of video format (portrait mode versus landscape mode) on recognition accuracy and spatial bias due to the different formats. Furthermore we designed extensive experiments to explore key aspects of portrait mode video recognition including the choice of data augmentation evaluation procedure the importance of temporal information and the role of audio modality. Building on the insights from our experimental results and the introduction of PortraitMode-400 our paper aims to inspire further research efforts in this emerging research area.
Universal image restoration is a practical and potential computer vision task for real-world applications. The main challenge of this task is handling the different degradation distributions at once. Existing methods mainly utilize task-specific conditions (e.g. prompt) to guide the model to learn different distributions separately named multi-partite mapping. However it is not suitable for universal model learning as it ignores the shared information between different tasks. In this work we propose an advanced selective hourglass mapping strategy based on diffusion model termed DiffUIR. Two novel considerations make our DiffUIR non-trivial. Firstly we equip the model with strong condition guidance to obtain accurate generation direction of diffusion model (selective). More importantly DiffUIR integrates a flexible shared distribution term (SDT) into the diffusion algorithm elegantly and naturally which gradually maps different distributions into a shared one. In the reverse process combined with SDT and strong condition guidance DiffUIR iteratively guides the shared distribution to the task-specific distribution with high image quality (hourglass). Without bells and whistles by only modifying the mapping strategy we achieve state-of-the-art performance on five image restoration tasks 22 benchmarks in the universal setting and zero-shot generalization setting.
Without bells and whistles by only modifying the mapping strategy we achieve state-of-the-art performance on five image restoration tasks 22 benchmarks in the universal setting and zero-shot generalization setting. Surprisingly by only using a lightweight model (only 0.89M) we could achieve outstanding performance. The source code and pre-trained models are available at https://github.com/iSEE-Laboratory/DiffUIR
Vision-language models (VLMs) pre-trained on web-scale datasets have demonstrated remarkable capabilities on downstream tasks when fine-tuned with minimal data. However many VLMs rely on proprietary data and are not open-source which restricts the use of white-box approaches for fine-tuning. As such we aim to develop a black-box approach to optimize VLMs through  natural language prompts  thereby avoiding the need to access model parameters feature embeddings or even output logits. We propose employing chat-based LLMs to search for the best text prompt for VLMs. Specifically we adopt an automatic "hill-climbing" procedure that converges to an effective prompt by evaluating the performance of current prompts and asking LLMs to refine them based on textual feedback all within a conversational process without human-in-the-loop. In a challenging 1-shot image classification setup our simple approach surpasses the white-box continuous prompting method (CoOp) by an average of 1.5% across 11 datasets including ImageNet. Our approach also outperforms both human-engineered and LLM-generated prompts.
In a challenging 1-shot image classification setup our simple approach surpasses the white-box continuous prompting method (CoOp) by an average of 1.5% across 11 datasets including ImageNet. Our approach also outperforms both human-engineered and LLM-generated prompts. We highlight the advantage of conversational feedback that incorporates both positive and negative prompts suggesting that LLMs can utilize the implicit "gradient" direction in textual feedback for a more efficient search. In addition we find that the text prompts generated through our strategy are not only more interpretable but also transfer well across different VLM architectures in a black-box manner. Lastly we demonstrate our framework on a state-of-the-art black-box VLM (DALL-E 3) for text-to-image optimization.
Open world object detection aims to identify objects of unseen categories and incrementally recognize them once their annotations are provided. In distinction to the traditional paradigm that is limited to predefined categories this setting promises a continual and generalizable way of estimating objectness using class-agnostic information. However achieving such decorrelation between objectness and class information proves challenging. Without explicit consideration existing methods usually exhibit low recall on unknown objects and can misclassify them into known classes. To address this problem we exploit three levels of orthogonality in the detection process: First the objectness and classification heads are disentangled by operating on separate sets of features that are orthogonal to each other in a devised polar coordinate system. Secondly a prediction decorrelation loss is introduced to guide the detector towards more general and class-independent prediction. Furthermore we propose a calibration scheme that helps maintain orthogonality throughout the training process to mitigate catastrophic interference and facilitate incremental learning of previously unseen objects. Our method is comprehensively evaluated on open world and incremental object detection benchmarks demonstrating its effectiveness in detecting both known and unknown objects. Code and models are available at https://github.com/feifeiobama/OrthogonalDet.
Large Vision-Language Models (LVLMs) have advanced considerably intertwining visual recognition and language understanding to generate content that is not only coherent but also contextually attuned. Despite their success LVLMs still suffer from the issue of object hallucinations where models generate plausible yet incorrect outputs that include objects that do not exist in the images. To mitigate this issue we introduce Visual Contrastive Decoding (VCD) a simple and training-free method that contrasts output distributions derived from original and distorted visual inputs. The proposed VCD effectively reduces the over-reliance on statistical bias and unimodal priors two essential causes of object hallucinations. This adjustment ensures the generated content is closely grounded to visual inputs resulting in contextually accurate outputs. Our experiments show that VCD without either additional training or the usage of external tools significantly mitigates the object hallucination issue across different LVLM families. Beyond mitigating object hallucinations VCD also excels in general LVLM benchmarks highlighting its wide-ranging applicability.
Generative object compositing emerges as a promising new avenue for compositional image editing. However the requirement of object identity preservation poses a significant challenge limiting practical usage of most existing methods. In response this paper introduces IMPRINT a novel diffusion-based generative model trained with a two-stage learning framework that decouples learning of identity preservation from that of compositing. The first stage is targeted for context-agnostic identity-preserving pretraining of the object encoder enabling the encoder to learn an embedding that is both view-invariant and conducive to enhanced detail preservation. The subsequent stage leverages this representation to learn seamless harmonization of the object composited to the background. In addition IMPRINT incorporates a shape-guidance mechanism offering user-directed control over the compositing process. Extensive experiments demonstrate that IMPRINT significantly outperforms existing methods and various baselines on identity preservation and composition quality.