MPEG4网络视频服务器在煤矿监控系统中的应用

远程视频监控系统是现代矿井安全生产监控系统的重要组成部分.本文介绍了一种基于MPEG4的网络视频服务器的设计与实现.该设备实现了实时视频MPEG4编码压缩,并通过嵌入式操作系统实现视频流的网络传输功能,符合当今视频监控技术的发展和应用推广.     

基于内容的视频运动对象分割技术研究

Withthedevelopmentofthemoderninformation society,moreandmoremultimediainformationis available.Sothetechnologyofmultimediaprocessing isbecomingtheimportanttaskfortheirrelevantarea ofscientist.Amongofthemultimedia,thevisualinfor mationismoreattractiveduetoitsdirect,vivid characteristic,butatthesametimethehugeamount ofvideodatacausesmanychallengesifthevideostor age,processingandtransmission.Videocompressionisnecessaryforefficientstorage,processingandtransmission.Motionpictureexperts group(MPEG)…     

MPEG-4技术及其在远程教育中的应用

较详细地介绍MPEG—4的特点、标准与制作，采用MPEG—4方式的多媒体课件的制作以及MPEG—4在远程教育中的应用及前景。     

MPEG4网络视频服务器在煤矿监控系统中的应用

远程视频监控系统是现代矿井安全生产监控系统的重要组成部分。本文介绍了一种基于MPEG4的网络视频服务器的设计与实现。该设备实现了实时视频MPEG4编码压缩,并通过嵌入式操作系统实现视频流的网络传输功能,符合当今视频监控技术的发展和应用推广。     

MPEG4网络视频服务器在煤矿监控系统中的应用

远程视频监控系统是现代矿井安全生产监控系统的重要组成部分。本文介绍了一种基于MPEG4的网络视频服务器的设计与实现。该设备实现了实时视频MPEG4编码压缩，并通过嵌入式操作系统实现视频流的网络传输功能，符合当今视频监控技术的发展和应用推广。     

Source extension based on ε-entropy

1 introduction 1 With the establishment of the Digital Video Encoding Standard H.264 by the International Telecommunications Union (ITU) and the Motion Picture Experts Group (MPEG), distortion digital video encoding technology matures little by little. As is known, H.264, which is a new video coding standard, adopts many new technologies, such as multi-model frame prediction, multi-reference frame motion estimation, variable dimension block motion compensation, 4×4 integer transformati…     

远程MPEG4视频传输与回放设计

给出了通过Internet传输MPEG4视频流的设计方案，内容涉及码流结构，控制，接收与回放技术，通过实验表明：采用本方案可以稳定可靠地实现因特网上视频的实时传输。     

校园软件推荐

AVI/MPEG/ASF/WMV Splitter是一个可以帮助你分离、切割、修整大型的AVI、MPEG、ASF或者WMV文件的视频转换工具,程序内置播放器,你可以按照时间或者将你喜欢的片断很轻松地截取下来,也可以帮助你将大型的多媒体视频文件分割为一个个小的多媒体视频文件,支持AVI、DIVX、MPEG-1、MPEG-2、MPEG-4、ASF、     

两种视频解压技术浅探

计算机硬、软件的发展、CPU速度的提高,给视频解压技术带来了生机,而计算机的视频解压,遵循MPEG标准,MPEG有两种解压方式;一种是MPEG解压卡,另一种是软件解压,由于解压卡的使用、安装、设置、兼容性等都不及软件解压,所以,随着计算机的发展,软件解压必然替代硬件解压技术。     

MPEG标准视频压缩技术的应用和比较

本文分析了MPEG—1、MPEG—2、MPEG—4等几种常见的视频压缩编码国际标准的特点,结合实际应用对这些技术进行了综合比较。     

基于运动连通性的初始视频对象提取

为了从视频序列中获取初始视频对象,提出了一种改进的基于运动连通性的初始视频对象提取算法.视频中的运动对象高度连通结构化,这就使得运动连通性是适用于视频对象分割的高级特征.据此首先对反映对象的一致性运动的累计帧差图进行尖锐噪声滤除,然后应用自适应阈值算法提取对象运动区域,接着根据运动连通性标记出最大连通区域,通过后处理得到视频对象的分割模版从而有效提取出初始视频对象.对比实验结果表明,该算法能自动、快速、准确地提取出初始视频对象,获得了理想的主客观分割效果.     

一种有效的基于运动矢量场的压缩域运动对象分割算法

In this paper an efficient compressed domain moving object segmentation algorithm is proposed, in which the motion vector (MV) field parsed from the compressed video is the only cue used for moving object segmentation. First the MV field is temporally and spatially normalized, and then accumulated by an iterative backward projection to enhance salient motions and alleviate noisy MVs. The accumulated MV field is then segmented into motion-homogenous regions using a modified statistical region growing approach. Finally, moving object regions are extracted in turn based on minimization of the joint prediction error using the estimated motion models of two region sets containing the candidate object region and other remaining regions, respectively. Experimental results on several H.264 compressed video sequences demonstrate good segmentation performance.     

Adaptive foreground and shadow segmentation using hidden conditional random fields

Video object segmentation is important for video surveillance, object tracking, video object recognition and video editing. An adaptive video segmentation algorithm based on hidden conditional random fields (HCRFs) is proposed, which models spatio-temporal constraints of video sequence. In order to improve the segmentation quality, the weights of spatio-temporal con- straints are adaptively updated by on-line learning for HCRFs. Shadows are the factors affecting segmentation quality. To separate foreground objects from the shadows they cast, linear transform for Gaussian distribution of the background is adopted to model the shadow. The experimental results demonstrated that the error ratio of our algorithm is reduced by 23% and 19% respectively, compared with the Gaussian mixture model (GMM) and spatio-temporal Markov random fields (MRFs).     

基于噪声与阴影抑制多模态背景模型的运动物体检测

针对场景照明变化、模型初始化以及阴影等问题, 提出了一种用于视频监视系统运动物体检测的统计多模态背景模型. 通过相隔固定的帧差值阈值化得到背景样本值, 并采用高斯核密度估计方法计算背景灰度的概率密度函数. 利用像素的邻域信息来去除由于摄像机抖动和场景小运动产生的噪声. HMMD色彩信息用来检测和抑制运动投射阴影. 实验结果验证了算法在交通监控前景物体分割中的有效性.     

一种基于直方图的实时自适应阈值分割方法

在视频序列图像中,视频图像分割的主要目的是要在视频序列中分割出运动实体,背景差法能够在实时性要求很高的情况下从一段视频中将当前帧图像跟背景图像作差,然后提取出运动目标,而对差图像进行二值化是关键,自适应阈值方法通过对差图像的直方图进行分析寻找直方图上的一个点,该点到直方图最高点与最低点之间的线段的距离最大,为求该点,本文提出了一种快速算法,以该点对应的灰度值作为阈值,这样运动目标就能够被精确地提取出来.     

SVM for density estimation and application to medical image segmentation

A method of medical image segmentation based on support vector machine （SVM） for density estimation is presented. We used this estimator to construct a prior model of the image intensity and curvature profile of the structure from training images. When segmenting a novel image similar to the training images, the technique of narrow level set method is used. The higher dimensional surface evolution metric is defined by the prior model instead of by energy minimization function. This method offers several advantages. First, SVM for density estimation is consistent and its solution is sparse. Second, compared to the traditional level set methods, this method incorporates shape information on the object to be segmented into the segmentation process. Segmentation results are demonstrated on synthetic images, MR images and ultrasonic images.     

Basic level object categories support the acquisition of novel adjectives: evidence from preschool-aged children

Two experiments examined 3- and 4-year-old children's ability to map novel adjectives to object properties. Sixty-four children were introduced to a target (e.g., a bumpy object), and asked to choose between (1) a matching test object (e.g., a different bumpy object), and (2) a contrasting test object (e.g., a smooth object). Four-year-olds successfully extended novel adjectives from the target to the matching test object whether these objects were drawn from the same, or different, basic level categories. In contrast, 3-year-olds' extensions were more restricted. They successfully extended novel adjectives if the target and test objects were drawn from the same basic level category but failed to do so if the objects were drawn from different basic level categories (Experiment 1). However, if 3-year-olds (n = 20) were first permitted to extend a novel adjective to objects within the same basic level category, they were subsequently able to extend that novel adjective broadly to objects from different basic level categories (Experiment 2). Thus, basic level object categories serve as an initial foundation in the process of mapping novel adjectives to object properties.     

Video classification for video quality prediction

INTRODUCTION Video content will be the main contributor to the future traffic in multimedia applications. Camcorders, digital cameras and lately mobile phones with video capturing capabilities have resulted in a wide spreading of multimedia to the masses. Quality of the captured/rendered videos is likely to be the major determining factor in the success of the new multi- media applications as well as product differentiation. Video processing chain includes video capturing, video pre-proce…     

基于直接寻找法的电阻抗断层成像

Solution to impedance distribution in electrical impedance tomography （EIT） is an ill-posed nonlinear inverse problem. It is especially difficult to reconstruct an EIT image in the center area of a measured object. Tikhonov regularization with some prior information is a sound regnlarization method for static electrical impedance tomography under the condition that some true impedance distribution information is known a priori. This paper presents a direct search method （DSM） as pretreatment of image reconstruction through which one not only can construct a regularization matrix which may locate in areas of impedance change, but also can obtain an initial impedance distribution more similar to the true impedance distribution, as well as better current modes which can better distinguish the initial distribution and the true distribution. Simulation results indicate that, by using DSM, resolution in the center area of the measured object can be improved significantly.     

视频中人脸的实时跟踪

介绍了一种简单、快速的实时视频人脸对象跟踪算法．在使用肤色检测算法进行人脸区域定位的基础上,采用差分运动估计,确定最大的搜索区域,在此区域使用两个正交的边缘梯度跟踪模型和内部肤色像素统计直方图跟踪模型跟踪人脸．本算法较好地解决了跟踪的连续性、实时性和精确度间的矛盾．实验结果表明本算法能够对人脸进行实时跟踪,具有一定实际应用价值．