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1.
Using string matching to detect video transitions   总被引:2,自引:0,他引:2  
The detection of shot boundaries in videos captures the structure of the image sequences by the identification of transitional effects. This task is important in the video indexing and retrieval domain. The video slice or visual rhythm is a single two-dimensional image sampling that has been used to detect several types of video events, including transitions. We use the longest common subsequence (LCS) between two strings to transform the video slice into one-dimensional signals obtaining a highly simplified representation of the video content. We also developed a chain of mathematical morphology operations over these signals leading to the detection of the most frequent video transitions, namely, cut, fade, and wipe. The algorithms are tested with success with various genres of videos.  相似文献   

2.
This paper addresses an important area in video processing, namely compressed domain processing. For video indexing, video scene transition detection is an essential step to segment the video. Current techniques for scene change detection tend to suffer from a major limitation as most of them cannot identify scene transitions in the compressed domain. Since most video is expected to be stored in the compressed domain, scene transition detection in this domain is highly desirable. In this paper an algorithm for video scene change detection is proposed to overcome this limitation. In this scheme, properties of the B-frames are used as it is capable of measuring the correlation between two adjacent reference frames. The results show that this scheme performs better than schemes based on P-frames. Proposed scheme can be directly applied with compressed data with minimum decompression and hence it is computationally efficient and makes real time implementations possible. Results show that video scene transitions can be identified satisfactorily with the proposed scheme.  相似文献   

3.
Production model based digital video segmentation   总被引:20,自引:1,他引:19  
Effective and efficient tools for segmenting and content-based indexing of digital video are essential to allow easy access to video-based information. Most existing segmentation techniques do not use explicit models of video. The approach proposed here is inspired and influenced by well established video production processes. Computational models of these processes are developed. The video models are used to classify the transition effects used in video and to design automatic edit effect detection algorithms. Video segmentation has been formulated as a production model based classification problem. The video models are also used to define segmentation error measures. Experimental results from applying the proposed technique to commercial cable television programming are presented.  相似文献   

4.
随着测井技术的不断进步,井下电视成像测井技术也取得突飞猛进的发展,本文介绍了一种新的井下电视成像技术——基于数字视频体制的井下电视实时成像测井技术:由摄像头拍摄的井下图像经模数转换和压缩处理,由3000米普通测井电缆传输到地面;在地面解压、视频转换然后显示或存储。本系统的数字传输采用相位连续的FSK调制,传输速率达到IMBPS,是目前最高的传输速率:地面采用软解调技术实现数据解调。  相似文献   

5.
Video applications are characterized by their increased requirements for huge storage spaces and timing synchronization. Video data storage is a critical issue due to the so-called I/O bottleneck problem in relation to the quality of service while accessing video applications. The main contribution of the paper is that it considers video data dependencies, access frequencies and timing constraints in order to introduce a video data representation model which guides the storage policies. Two video data representation levels are considered to capture the frequencies of accesses at external (video objects) and internal (video clips) levels. A simulation model has been developed in order to evaluate the placement strategies. Video data placement is performed on a tertiary storage subsystem by both constructive and iterative improvement policies. Iterative improvement placement has been proven to outperform the other video data placement approaches.  相似文献   

6.
Full motion video traffic is envisaged to be a major source for Internet and broadband integrated services digital networks (B-ISDN). Accurate traffic models of full motion video are needed to design networks and improve video services. Auto-regressive process (AR) proves to be a viable modeling approach of full motion video. A considerable amount of effort on AR video modeling has been reported in the recent studies which need to be thoroughly investigated. The aim of this paper is: (1) to survey a number of AR models for full motion video; (2) to classify the models according to their properties and framework; (3) to compare and contrast the models based on their attributes: residual, coding scheme, capturing scene changes, number of parameters, level of modeling, and complexity; (4) to show the ability of these models to predict accurately different aspects of network performance; (5) to give recommendations that might be helpful in determining the appropriate model for full motion video based on the target application; (6) to give direction for future work on this important modeling scheme.  相似文献   

7.
This paper presents a two-level queueing system for dynamic summarization and interactive searching of video content. Video frames enter the queueing system; some insignificant and redundant frames are removed; the remaining frames are pulled out of the system as top-level key frames. Using an energy-minimization method, the first queue removes the video frames that constitute the gradual transitions of video shots. The second queue measures the content similarity of video frames and reduces redundant frames. In the queueing system, all key frames are linked in a directed-graph index structure, allowing video content to be accessed at any level-of-detail. Furthermore, this graph-based index structure enables interactive video content exploration, and the system is able to retrieve the video key frames that complement the video content already viewed by users. Experimental results on four full-length videos show that our queueing system performs much better than two existing methods on video key frame selection at different compression ratios. The evaluation on video content search shows that our interactive system is more effective than other systems on eight video searching tasks. Compared with the regular media player, our system reduces the average content searching time by half.  相似文献   

8.
This paper describes a network-based video capture and processing peripheral, called the Vidboard, for a distributed multimedia system centered around a 1-Gbit/s asynchronous transfer mode (ATM) network. The Vidboard is capable of generating full-motion video streams having a range of presentation (picture size, color space, etc.) and network (traffic, transport, etc.) characteristics. The board is also capable of decoupling video from the real-time constraints of the television world, which allows easier integration of video into the software environment of computer systems. A suite of ATM-based protocols has been developed for transmitting video from the Vidboard to a workstation, and a series of experiments are presented in which video is transmitted to a workstation for display.  相似文献   

9.
依据目前的研究状况和家庭视频的特点,提出一种适用于家庭视频的基于场景代表帧的视频摘要生成方法.场景代表帧的选取是在提取法得到.最后给出了基于内容的家庭视频摘要系统.  相似文献   

10.
陈卓夷 《计算机科学》2007,34(4):119-120
关键帧提取是基于内容的视频检索的一个重要的组成部分,所提取的关键帧的有效性,直接影响视频检索的结果。文中提出了一种基于非参数密度估计聚类的关键帧提取方法。首先,通过提取图像的颜色特征和运动特征,然后利用均值漂移聚类方法对融合了颜色和运动信息的特征空间进行聚类。它能自动确定类别数并具有严格的收敛陛,从而大大减少了运算量,提高了运算速度。实验证明,本方法的提取结果与人的主观视觉感知系统具有良好的一致性。  相似文献   

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