共查询到20条相似文献,搜索用时 93 毫秒
1.
2.
本文主要讨论了在多媒体数据库的检索技术中,围绕图像、视频、音频等多媒体信息,实现多媒体数据库基于内容的检索。 相似文献
3.
基于内容的音频检索:概念和方法 总被引:38,自引:1,他引:37
F过去对视觉媒体的检索,如图象和视频,进行了大量的研究。但是我们注意到音频也是多媒体中的一种典型媒体,是信息的一种常用载体。常规的自理是把数字音频当成非结构化流媒体。然而音频是语音的载体、包含丰富的听觉特征,并且具有结构信息。因此需要并且可以基于这些内容对音频进行存取。本文根据当前相关研究的进展,综述基于内容的音频检索方法,包括面向语音、音乐和音频分析的检索、音频分割等;分析并总结出音频内容及其检 相似文献
4.
5.
视频数据中的音频流包含了丰富的语义信息.在基于内容的视频检索中,对音频信息的分析是不可分割的一部分.本文主要讨论基于内容的音频场景分割,分析各种音频特征及提取方法,并在此基础上提出一种新的音频流分割方法,根据六种音频类型(语音、音乐、静音、环境音、纯语音、音乐背景下的语音和环境音背景下的语音)的音频特征对视频数据中的音频流分割音频场景.实验证明该方法是有效的,在保证一定的分割精度的同时,准确率和查全率都得到了较大的提高. 相似文献
6.
如何在海量的图像、视频和音频数据中快速找到用户关心的内容是检索领域研究的热点之一.从体育视频结构的特点出发,分析并给出一种语义标注及分层索引方法,对于一个体育视频数据,可通过与特征库匹配自动完成视频数据标注.检索时根据分层分级结构索引,能快速定位搜索范围,并根据用户反馈信息,执行一个新的动态学习检索过程,提高检索效率. 相似文献
7.
8.
一、使用音频和视频进行交流第一次运行NetMeeting时,音频调节向导将优化你的音频设置以确信你大声阅读时能够被清楚地听到。如果音频质量越来越差,你就需要重新调节音频设置。当你呼叫或接收呼叫时,只要你的计算机具备必要的硬件,NetMeeting就可以开始传输音频和视频。当你在呼叫期间,可以通过更改视频选项为手工调节来控制伺时发送或接收视频。虽然在会议中有几对人可以立即交换音频和视频,但是每人在同一时刻只能向另外一个人发送和接收音频及视频。你还可以在会议的任何时候从一个人切换到另一人的连接。1.调节音频(1)单击工… 相似文献
9.
10.
AVS是我国具备自主知识产权的第2代信源编码标准,是一套包含系统、视频、音频、媒体版权管理在内的完整标准体系,在未来中国数字音视频产业中有广阔的应用前景。设计并实现了一套基于AVS视频编解码技术的视频监控系统,可以对AVS视频流自动进行处理。该系统结合AVS视频编解码、背景/非背景分类、人脸检测与识别等技术,可输入文本、图片和视频段对出现在监控视频中的人物进行身份的自动识别,并引入两级索引结构以达到快速检索的目的,在数字监控、门禁控制以及身份识别等方面有一定的应用价值。 相似文献
11.
Many daily activities present information in the form of a stream of text, and often people can benefit from additional information on the topic discussed. TV broadcast news can be treated as one such stream of text; in this paper we discuss finding news articles on the web that are relevant to news currently being broadcast.
We evaluated a variety of algorithms for this problem, looking at the impact of inverse document frequency, stemming, compounds, history, and query length on the relevance and coverage of news articles returned in real time during a broadcast. We also evaluated several postprocessing techniques for improving the precision, including reranking using additional terms, reranking by document similarity, and filtering on document similarity. For the best algorithm, 84–91% of the articles found were relevant, with at least 64% of the articles being on the exact topic of the broadcast. In addition, a relevant article was found for at least 70% of the topics. 相似文献
12.
基于三维文档向量的自适应话题追踪器模型 总被引:1,自引:0,他引:1
话题追踪(TT)是研究自动追踪事件动态发展过程的一种信息智能获取技术,是话题检测与追踪(TDT)技术的一个子任务,其目标在于自动发现新闻报道信息流中与某一已知话题有关的新报道。该文通过分析传统文档向量空间模型的不足,结合新闻报道的特征,提出了一种三维文档向量模型,在此基础上建立了一种符合新闻报道特征的话题模型。该话题模型在追踪过程中能够根据事件的动态发展进行自我学习和自我修正。结合话题模型,该文还设计了一种自适应的KNN新闻话题追踪器,从而形成了一种完整的中文话题追踪器模型。实验数据表明该方法在描述新闻话题、避免话题漂移方面具有一定优势,在中文话题追踪领域取得了较好效果。 相似文献
13.
Numerous paper-based newspapers have been transformed into a digital format and published on the Internet. Digital newspapers
are gradually becoming a popular electronic media for conveying information immediately. Google developed a powerful news
service, Google news alert, based on the Google news aggregator for tracking user-interested new events utilizing a keywords
matching approach. However, this service only monitors and tracks news events using the keyword-matching scheme; consequently,
the Google news alert retrieves many irrelevant news events and sends them to users. In other words, the current service cannot
monitor news events via a specific news topic; although recall rate is high, the precision rate is low when tracking user-interested
news events. Thus, this study presents a novel personalized e-news monitoring agent system that employs the topic-tracking-based
approach, improving the flaw of the keyword-based approach, for tracking user-interested news events on Google News site.
The proposed scheme simultaneously considers both similarities and the semantic relationships among news topics to track news
events. Additionally, to further support the promotion of the accuracy rate in tracking user-interested Chinese news events,
the Chinese word segmentation system ECScanner (An Extension Chinese Lexicon Scanner) with new word extension is proposed
for the Chinese word segmentation process. Experimental results demonstrated that the proposed scheme, based on topic-based
approach, is superior to the keyword-based approach used by Google news alert in terms of precision rate, and retains a high
recall rate when tracking user-interested news events. Compared with the conventional Chinese word segmentation system CKIP
(Chinese Knowledge Information Processing), experimental results also confirmed that using the proposed ECScanner with novel
extension mechanism for new words improves the accuracy rate in tracking user-interested news events. 相似文献
14.
15.
基于语义信息提取的新闻视频场景分割方法 总被引:3,自引:1,他引:3
随着数字视频的广泛应用,视频数据库系统已成为多媒体领域的一个研究热点。在建立视频数据库的过程中,视频场景的分割是一个重要而又难以解决的问题。文章从分析新闻视频场景所特有的结构特征入手,提出了一种基于语义信息提取的新闻视频场景分割新方法,该方法通过对音频流和视频流中的镜头变换、主持人镜头、主题字幕和静音区间等语义信息的提取和分析来实现新闻视频场景的分割。实验表明,采用该文提出的方法,场景分割正确率可达86.9%,较好地解决了新闻视频场景分割问题。 相似文献
16.
新闻视频条目分割是新闻视频检索和浏览中重要的底层支持技术,本文提出了一种融合主持人模板匹配和主题字幕帧检测的多模态新闻视频条目分割算法。先用基于主持人模板的算法进行第一次分割,再用基于改进的字幕检测方法进行第二次分割,最后将两次分割的结果融合并去除重复的分割点。实验证明,该算法对新闻视频条目分割具有较好的效果。 相似文献
17.
News recommendation and user interaction are important features in many Web-based news services. The former helps users identify the most relevant news for further information. The latter enables collaborated information sharing among users with their comments following news postings. This research is intended to marry these two features together for an adaptive recommender system that utilizes reader comments to refine the recommendation of news in accordance with the evolving topic. This then turns the traditional “push-data” type of news recommendation to “discussion” moderator that can intelligently assist online forums. In addition, to alleviate the problem of recommending essentially identical articles, the relationship (duplicate, generalization, or specialization) between recommended news articles and the original posting is investigated. Our experiments indicate that our proposed solutions provide an improved news recommendation service in forum-based social media. 相似文献
18.
针对当前基于海量公开新闻数据的重大事件趋势预测研究在特征选择上的局限性问题,结合人工智能相关技术对现有方法进行优化改进,提出一种融合语义与事件特征的重大事件趋势预测方法。利用网络爬虫技术辅助数据采集;利用主题模型与事件抽取技术辅助海量新闻数据的特征集构建与向量表示,并针对LDA主题模型在特征词提取上存在偏向性的问题,提出一种改进模型IDFLDA;利用机器学习分类模型进行预测结果输出。以朝鲜核行为预测为例对提出方法进行验证,预测结果表明,该方法的预测性能优于依赖专家知识进行特征集构建的传统方法,能有效进行重大事件的趋势预测,为战略决策提供辅助支持。 相似文献
19.
新闻视频的场景分段索引及摘要生成 总被引:12,自引:0,他引:12
在提出一种新闻视频检索系统结构的基础上,介绍了基于标题条检测的新闻场景分段索引方法,并阐述了两种新闻摘要的生成策略.该方法利用新闻节目标题条出现的时空位置线索,结合标题关键词的识别,建立起一个层次化的新闻视频索引结构,并帮助用户通过新闻摘要实现不同要求的视频浏览.实验证明该方法有较高的检索成功率,并且简单快捷,为新闻视频检索提供了新的有效途径. 相似文献
20.
Storyline-based summarization for news topic retrospection 总被引:2,自引:0,他引:2
Electronics newspapers gradually become main sources for news readers. When facing the numerous reports on a series of events in a topic, a summary of stories from news reports will benefit news readers in reviewing the news topic efficiently. Besides identifying events and presenting news titles and keywords the TDT (Topic Detection and Tracking) techniques are used to do, a summarized text to present event evolution is necessary for general news readers to review events under a news topic. This paper proposes a topic retrospection process and implements the SToRe (Story-line based Topic Retrospection) system that identifies various events under a news topic, and composes a summary that news readers can get the sketch of event evolution in the topic. It consists of three main functions: event identification, main storyline construction and storyline-based summarization. The constructed main storyline can remove the irrelevant events and present a main theme. The storyline-based summarization extracts the representative sentences and takes the main theme as the template to compose the summary. The storyline summary not only provides readers enough information to understand the development of a news topic, but also serves as an index for readers to search corresponding news reports. Following a design science paradigm, a lab experiment is conducted to evaluate the SToRe system in the question-and-answer (Q&A) setting. The experimental results show that SToRe enables news readers to effectively and efficiently capture the evolution of a news topic. 相似文献