26 research outputs found
VadCLIP: Adapting Vision-Language Models for Weakly Supervised Video Anomaly Detection
The recent contrastive language-image pre-training (CLIP) model has shown
great success in a wide range of image-level tasks, revealing remarkable
ability for learning powerful visual representations with rich semantics. An
open and worthwhile problem is efficiently adapting such a strong model to the
video domain and designing a robust video anomaly detector. In this work, we
propose VadCLIP, a new paradigm for weakly supervised video anomaly detection
(WSVAD) by leveraging the frozen CLIP model directly without any pre-training
and fine-tuning process. Unlike current works that directly feed extracted
features into the weakly supervised classifier for frame-level binary
classification, VadCLIP makes full use of fine-grained associations between
vision and language on the strength of CLIP and involves dual branch. One
branch simply utilizes visual features for coarse-grained binary
classification, while the other fully leverages the fine-grained language-image
alignment. With the benefit of dual branch, VadCLIP achieves both
coarse-grained and fine-grained video anomaly detection by transferring
pre-trained knowledge from CLIP to WSVAD task. We conduct extensive experiments
on two commonly-used benchmarks, demonstrating that VadCLIP achieves the best
performance on both coarse-grained and fine-grained WSVAD, surpassing the
state-of-the-art methods by a large margin. Specifically, VadCLIP achieves
84.51% AP and 88.02% AUC on XD-Violence and UCF-Crime, respectively. Code and
features will be released to facilitate future VAD research.Comment: Submitte
Take a Prior from Other Tasks for Severe Blur Removal
Recovering clear structures from severely blurry inputs is a challenging
problem due to the large movements between the camera and the scene. Although
some works apply segmentation maps on human face images for deblurring, they
cannot handle natural scenes because objects and degradation are more complex,
and inaccurate segmentation maps lead to a loss of details. For general scene
deblurring, the feature space of the blurry image and corresponding sharp image
under the high-level vision task is closer, which inspires us to rely on other
tasks (e.g. classification) to learn a comprehensive prior in severe blur
removal cases. We propose a cross-level feature learning strategy based on
knowledge distillation to learn the priors, which include global contexts and
sharp local structures for recovering potential details. In addition, we
propose a semantic prior embedding layer with multi-level aggregation and
semantic attention transformation to integrate the priors effectively. We
introduce the proposed priors to various models, including the UNet and other
mainstream deblurring baselines, leading to better performance on severe blur
removal. Extensive experiments on natural image deblurring benchmarks and
real-world images, such as GoPro and RealBlur datasets, demonstrate our
method's effectiveness and generalization ability
Stock Market Prediction via Deep Learning Techniques: A Survey
The stock market prediction has been a traditional yet complex problem
researched within diverse research areas and application domains due to its
non-linear, highly volatile and complex nature. Existing surveys on stock
market prediction often focus on traditional machine learning methods instead
of deep learning methods. Deep learning has dominated many domains, gained much
success and popularity in recent years in stock market prediction. This
motivates us to provide a structured and comprehensive overview of the research
on stock market prediction focusing on deep learning techniques. We present
four elaborated subtasks of stock market prediction and propose a novel
taxonomy to summarize the state-of-the-art models based on deep neural networks
from 2011 to 2022. In addition, we also provide detailed statistics on the
datasets and evaluation metrics commonly used in the stock market. Finally, we
highlight some open issues and point out several future directions by sharing
some new perspectives on stock market prediction
Kernel sparse tracking with compressive sensing
Online tracking is a challenging task to develop effective and efficient models to account for appearance change. However, most tracking algorithms only consider the holistic or local information and do not make full use of the appearance information. In this study, a novel tracking algorithm with sparse representation is proposed and the online classifier is learned to discriminate the target from the background. To reduce visual drift problem which is encountered in object tracking, a two鈥恠tage sparse representation method is proposed. The holistic information is used to estimate the initial tracking position, and the local information is used to determine the final tracking position. To improve the performance of the classifier and robustness of the algorithm, the kernel function is applied on the sparse representation. Moreover, the dimension of the target is reduced via compressive sensing. Besides, a simple and effective method for dictionary update is proposed. Both qualitative and quantitative evaluations on challenging image sequences demonstrate that the proposed algorithm performs favourably against several state鈥恛f鈥恡he鈥恆rt algorithms
The Regulatory Role of Casein Glycomacropeptide (CGMP) in the Fecal Flora of Mice with Ulcerative Colitis
ABSTRACT Objective: To explore the regulatory role of Casein glycomacropeptide (CGMP) in the fecal flora of mice with Ulcerative colitis (UC). Methods: The BALB/c mice were divided into a normal control group, a model group, CGMP groups with low doses (5 mg/kg路d), middle doses (50 mg/kg路d) and high doses (500 mg/kg路d), and a Sulfasalazine (SASP) group. Except the normal control group, all mice were treated with Oxazolone (OXZ) by perfusion to induce the UC model. In contrast, the mice in the normal control group and the model group were treated with an equal volume of saline for 7 consecutive days, which the changes in the fecal flora of the mouse intestines were evaluated by Fluorescence in situ hybridization (FISH) and DNA staining. Conclusion: CGMP can rectify the structural imbalances in the colon fecal flora in mice with UC and can improve the proportion of dominant flora in the intestine. CGMP at a dose of 50 mg/kg路d can significantly reduce the number of Enterobacteriaceae and Enterococci and promote the proliferation of Bifidobacteria, Lactobacilli, Bacteroides and Clostridium coccoides in the intestine
Modulation of mice fecal microbiota by administration of casein glycomacropeptide
Casein glycomacropeptide (GMP) is known to promote the in vitro growth of Bifidobacteria and Lactobacilli. In this paper, we used conven- tional culture techniques and fluorescent in situ hybridization (FISH) techniques to investigate the effect of casein GMP on mice fecal microbiota. The population structure of the intestinal microbiota, including Lactobacillus, Bifidobacteria, Enterococcus, coliforms and Enterobacteriaceae, was tested and compared. After consecutive administration of casein GMP for 15 days, numbers of Lactobacillus and Bifidobacteria increased significantly (P<0.01), numbers of Enterobacteriaceae and Coliforms decreased significantly (P<0.05) while no significant changes were observed for Enterococcus. The detection limits of FISH technique were significantly lower (P<0.01) than the traditional culture method. These results suggested that consumption of casein GMP had a prebiotic effect on male BALB/c mice. Casein GMP helped establish a healthier intestinal microbiota. Additionally, FISH was proved to be a rapid and relatively low-cost detection method that can be used to further our understanding of human intestinal microbiota