A Web video retrieval method using hierarchical structure of Web video groups

In this paper, we propose a Web video retrieval method that uses hierarchical structure of Web video groups. Existing retrieval systems require users to input suitable queries that identify the desired contents in order to accurately retrieve Web videos; however, the proposed method enables retrieval of the desired Web videos even if users cannot input the suitable queries. Specifically, we first select representative Web videos from a target video dataset by using link relationships between Web videos obtained via metadata “related videos” and heterogeneous video features. Furthermore, by using the representative Web videos, we construct a network whose nodes and edges respectively correspond to Web videos and links between these Web videos. Then Web video groups, i.e., Web video sets with similar topics are hierarchically extracted based on strongly connected components, edge betweenness and modularity. By exhibiting the obtained hierarchical structure of Web video groups, users can easily grasp the overview of many Web videos. Consequently, even if users cannot write suitable queries that identify the desired contents, it becomes feasible to accurately retrieve the desired Web videos by selecting Web video groups according to the hierarchical structure. Experimental results on actual Web videos verify the effectiveness of our method

Few-shot Personalized Saliency Prediction Based on Inter-personnel Gaze Patterns

This paper presents few-shot personalized saliency prediction based on inter-personnel gaze patterns. In contrast to a general saliency map, a personalized saliecny map (PSM) has been great potential since its map indicates the person-specific visual attention that is useful for obtaining individual visual preferences from heterogeneity of gazed areas. The PSM prediction is needed for acquiring the PSM for the unseen image, but its prediction is still a challenging task due to the complexity of individual gaze patterns. For modeling individual gaze patterns for various images, although the eye-tracking data obtained from each person is necessary to construct PSMs, it is difficult to acquire the massive amounts of such data. Here, one solution for efficient PSM prediction from the limited amount of data can be the effective use of eye-tracking data obtained from other persons. In this paper, to effectively treat the PSMs of other persons, we focus on the effective selection of images to acquire eye-tracking data and the preservation of structural information of PSMs of other persons. In the experimental results, we confirm that the above two focuses are effective for the PSM prediction with the limited amount of eye-tracking data.Comment: 5pages, 3 figure

RGMIM: Region-Guided Masked Image Modeling for COVID-19 Detection

Background and objective: Self-supervised learning is rapidly advancing computer-aided diagnosis in the medical field. Masked image modeling (MIM) is one of the self-supervised learning methods that masks a subset of input pixels and attempts to predict the masked pixels. Traditional MIM methods often employ a random masking strategy. In comparison to ordinary images, medical images often have a small region of interest for disease detection. Consequently, we focus on fixing the problem in this work, which is evaluated by automatic COVID-19 identification. Methods: In this study, we propose a novel region-guided masked image modeling method (RGMIM) for COVID-19 detection in this paper. In our method, we devise a new masking strategy that employed lung mask information to identify valid regions to learn more useful information for COVID-19 detection. The proposed method was contrasted with five self-supervised learning techniques (MAE, SKD, Cross, BYOL, and, SimSiam). We present a quantitative evaluation of open COVID-19 CXR datasets as well as masking ratio hyperparameter studies. Results: When using the entire training set, RGMIM outperformed other comparable methods, achieving 0.962 detection accuracy. Specifically, RGMIM significantly improved COVID-19 detection in small data volumes, such as 5% and 10% of the training set (846 and 1,693 images) compared to other methods, and achieved 0.957 detection accuracy even when only 50% of the training set was used. Conclusions: RGMIM can mask more valid lung-related regions, facilitating the learning of discriminative representations and the subsequent high-accuracy COVID-19 detection. RGMIM outperforms other state-of-the-art self-supervised learning methods in experiments, particularly when limited training data is used.Comment: Under revie

Soft-Label Anonymous Gastric X-ray Image Distillation

This paper presents a soft-label anonymous gastric X-ray image distillation method based on a gradient descent approach. The sharing of medical data is demanded to construct high-accuracy computer-aided diagnosis (CAD) systems. However, the large size of the medical dataset and privacy protection are remaining problems in medical data sharing, which hindered the research of CAD systems. The idea of our distillation method is to extract the valid information of the medical dataset and generate a tiny distilled dataset that has a different data distribution. Different from model distillation, our method aims to find the optimal distilled images, distilled labels and the optimized learning rate. Experimental results show that the proposed method can not only effectively compress the medical dataset but also anonymize medical images to protect the patient's private information. The proposed approach can improve the efficiency and security of medical data sharing.Comment: Published as a conference paper at ICIP 202

Self-Supervised Learning for Gastritis Detection with Gastric X-Ray Images

We propose a novel self-supervised learning method for medical image analysis. Great progress has been made in medical image analysis because of the development of supervised learning based on deep convolutional neural networks. However, annotating complex medical images usually requires expert knowledge, making it difficult for a wide range of real-world applications ($e.g.$, computer-aided diagnosis systems). Our self-supervised learning method introduces a cross-view loss and a cross-model loss to solve the insufficient available annotations in medical image analysis. Experimental results show that our method can achieve high detection performance for gastritis detection with only a small number of annotations

Dataset Distillation using Parameter Pruning

The acquisition of advanced models relies on large datasets in many fields, which makes storing datasets and training models expensive. As a solution, dataset distillation can synthesize a small dataset that preserves most information of the original large dataset. The recently proposed dataset distillation method by matching network parameters has been proven effective for several datasets. However, the dimension of network parameters is usually large. And we found that a few parameters in the distillation process are difficult to match, which harms the distillation performance. Based on this observation, this paper proposes a new method to solve the problem using parameter pruning. The proposed method can synthesize more robust distilled datasets and improve the distillation performance by pruning difficult-to-match parameters in the distillation process. Experimental results on three datasets show that the proposed method outperformed other state-of-the-art dataset distillation methods

Dataset Distillation for Medical Dataset Sharing

Sharing medical datasets between hospitals is challenging because of the privacy-protection problem and the massive cost of transmitting and storing many high-resolution medical images. However, dataset distillation can synthesize a small dataset such that models trained on it achieve comparable performance with the original large dataset, which shows potential for solving the existing medical sharing problems. Hence, this paper proposes a novel dataset distillation-based method for medical dataset sharing. Experimental results on a COVID-19 chest X-ray image dataset show that our method can achieve high detection performance even using scarce anonymized chest X-ray images

A Genetic Algorithm for Path Generation and its Applications

Abstract-Path generation is an optimization problem mainly performed on grid maps that combines generation of paths with minimization of their cost. Several methods that belong to the class of exhaustive searches are available; however, these methods are only able to obtain a single path as a solution for each iteration of the search. Conversely, while genetic algorithms involving a type of multipoint search methods have been proposed as suitable candidates for this problem with the goal of simultaneously searching for multiple candidate paths, these methods are limited to particular applications, and there are limitations on the types of paths that can be represented. This paper therefore proposes a path generation method that is applicable to more general-purpose applications compared to previous methods based on a new design of the genotype used in the genetic algorithm

Team Tactics Estimation in Soccer Videos Based on a Deep Extreme Learning Machine and Characteristics of the Tactics

A novel method for estimating team tactics in soccer videos based on a Deep Extreme Learning Machine (DELM) and unique characteristics of tactics is presented in this paper. The proposed method estimates the tactics of each team from players formations and enables successful training from a limited amount of training data. Specifically, the estimation of tactics consists of two stages. First, by utilizing two DELMs corresponding to the two teams, the proposed method estimates the provisional tactics of each team. Second, the proposed method updates the team tactics based on unique characteristics of soccer tactics, the relationship between tactics of the two teams and information on ball possession. Consequently, since the proposed method estimates the team tactics that satisfy these characteristics, accurate estimation results can be obtained. In an experiment, the proposed method is applied to actual soccer videos to verify its effectiveness

Extracting Hierarchical Structure of Web Video Groups Based on Sentiment-Aware Signed Network Analysis

Sentiment in multimedia contents has an influence on their topics, since multimedia contents are tools for social media users to convey their sentiment. Performance of applications such as retrieval and recommendation will be improved if sentiment in multimedia contents can be estimated; however, there have been few works in which such applications were realized by utilizing sentiment analysis. In this paper, a novel method for extracting the hierarchical structure of Web video groups based on sentiment-aware signed network analysis is presented to realize Web video retrieval. First, the proposed method estimates latent links between Web videos by using multimodalfeatures of contents and sentiment features obtained from texts attached to Web videos. Thus, our method enables construction of a signed network that reflects not only similarities but also positive and negative relations between topics of Web videos. Moreover, an algorithm to optimize a modularity-based measure, which can adaptively adjust the balance between positive and negative edges, was newly developed. This algorithm detects Web video groups with similar topics at multiple abstraction levels; thus, successful extraction of the hierarchical structure becomes feasible. By providing the hierarchical structure, users can obtain an overview of many Web videos and it becomes feasible to successfully retrieve the desired Web videos. Results of experiments using a new benchmark dataset, YouTube-8M, validate the contributions of this paper, i.e., 1) the first attempt to utilize sentiment analysis for Web video grouping and 2) a novel algorithm for analyzing a weighted signed network derived from sentiment and multimodal features