{"msg":"第六节 计算机应用","code":200,"data":{"currentIndex":null,"examId":null,"examTime":null,"questionList":[{"id":"796238165999374337","title":"彩色视频信号数字化的过程中，利用图像子采样技术通过降低对（63）的采样频率，以达到减少数据量的目的。","analyze":"将彩色视频信号数字化时，利用图像子采样技术通过降低色度信号的采样频率，以减少数据量。","multi":0,"questionType":1,"answer":"D","chooseItem":["796238167148613633"],"itemList":[{"id":"796238167106670593","questionId":"796238165999374337","content":" 亮度信号","answer":0,"chooseValue":"A"},{"id":"796238167123447809","questionId":"796238165999374337","content":" 饱和度信号","answer":0,"chooseValue":"B"},{"id":"796238167136030721","questionId":"796238165999374337","content":" 同步信号","answer":0,"chooseValue":"C"},{"id":"796238167148613633","questionId":"796238165999374337","content":" 色度信号","answer":1,"chooseValue":"D"}],"userAnswer":null,"userChooseItem":null,"answerCorrect":null,"userCollect":null},{"id":"796238136370810881","title":"<p><strong>请作答第<span style=\"color: red\">2</span>个空。</strong></p>MPEG-1视频编码标准中定义了（62）种不同类型的视频帧，其中没有使用帧间编码能够直接作为索引点的是（63）。","analyze":"本题考查对MPEG-1标准中视频编码技术的了解。<br>MPEG-1标准中，视频图像的帧序列包括帧内图像(I帧)、预测图像(P帧(和插补图像(B帧，或称双向预测图像(3种。帧内图像不参照任何过去的或者将来的其他图像帧，压缩编码直接采用类JPEG的压缩算法，故其可以直接作为索引和访问点；预测图像使用基于运动补偿的单向帧间预测编码；而插补图像则使用双向帧间预测编码。","multi":0,"questionType":1,"answer":"A","chooseItem":["796238137289363457"],"itemList":[{"id":"796238137289363457","questionId":"796238136370810881","content":" I帧","answer":1,"chooseValue":"A"},{"id":"796238137301946369","questionId":"796238136370810881","content":" P帧","answer":0,"chooseValue":"B"},{"id":"796238137310334977","questionId":"796238136370810881","content":" B帧","answer":0,"chooseValue":"C"},{"id":"796238137322917889","questionId":"796238136370810881","content":" S帧","answer":0,"chooseValue":"D"}],"userAnswer":null,"userChooseItem":null,"answerCorrect":null,"userCollect":null},{"id":"796238119895584769","title":"(62)标准的目标是制定一个开放的多媒体应用框架标准。","analyze":"本题考查考生对各种多媒体相关的国际标准的了解情况。H.264是国际电信联盟(ITU)制定的视频信号和音频信号的压缩编码标准；X3D是由Web3D联盟专为Internet应用设计的三维图形标记语言，是VRML标准的升级版本；MPEG-21是ISO/IEC制定的一个标准，致力于定义多媒体应用的一个开放框架。","multi":0,"questionType":1,"answer":"B","chooseItem":["796238120835108865"],"itemList":[{"id":"796238120822525953","questionId":"796238119895584769","content":" H.264","answer":0,"chooseValue":"A"},{"id":"796238120835108865","questionId":"796238119895584769","content":" MPEG-21","answer":1,"chooseValue":"B"},{"id":"796238120856080385","questionId":"796238119895584769","content":" XML","answer":0,"chooseValue":"C"},{"id":"796238120872857601","questionId":"796238119895584769","content":" X3D","answer":0,"chooseValue":"D"}],"userAnswer":null,"userChooseItem":null,"answerCorrect":null,"userCollect":null},{"id":"796238141454307329","title":"MPEG-7是ISO制定的（63）标准。","analyze":"MPEG是Moving Picture Expert Group的简称，最初是指由国际标准化组织ISO和国际电工委员会IEC联合组成的一个研究视频和音频编码标准的专家组。同时MPEG也用来命名这个小组所负责开发的一系列音、视频编码标准和多媒体应用标准。<br>这个专家组至今为止己制定和制定中的标准主要包括MPEG-1、MPEG-2、MPEG-4、MPEG-7和MPEG-21标准。其中MPEG-1、MPEG-2和MPEG-4主要针对音、视频编码技术，而MPEG-7和MPEG-21则已经不再是音、视频压缩编码的标准：MPEG-7是多媒体内容描述接口标准，而MPEG-21是多媒体应用框架标准。","multi":0,"questionType":1,"answer":"D","chooseItem":["796238142477717505"],"itemList":[{"id":"796238142393831425","questionId":"796238141454307329","content":" 多媒体视频压缩编码","answer":0,"chooseValue":"A"},{"id":"796238142418997249","questionId":"796238141454307329","content":" 多媒体音频压缩编码","answer":0,"chooseValue":"B"},{"id":"796238142448357377","questionId":"796238141454307329","content":" 多媒体音、视频压缩编码","answer":0,"chooseValue":"C"},{"id":"796238142477717505","questionId":"796238141454307329","content":" 多媒体内容描述接口","answer":1,"chooseValue":"D"}],"userAnswer":null,"userChooseItem":null,"answerCorrect":null,"userCollect":null},{"id":"796238133103448065","title":"<p><strong>请作答第<span style=\"color: red\">1</span>个空。</strong></p>MPEG-1视频编码标准中定义了（62）种不同类型的视频帧，其中没有使用帧间编码能够直接作为索引点的是（63）。","analyze":"本题考查对MPEG-1标准中视频编码技术的了解。<br>MPEG-1标准中，视频图像的帧序列包括帧内图像(I帧)、预测图像(P帧(和插补图像(B帧，或称双向预测图像(3种。帧内图像不参照任何过去的或者将来的其他图像帧，压缩编码直接采用类JPEG的压缩算法，故其可以直接作为索引和访问点；预测图像使用基于运动补偿的单向帧间预测编码；而插补图像则使用双向帧间预测编码。","multi":0,"questionType":1,"answer":"B","chooseItem":["796238134177189889"],"itemList":[{"id":"796238134164606977","questionId":"796238133103448065","content":" 2","answer":0,"chooseValue":"A"},{"id":"796238134177189889","questionId":"796238133103448065","content":" 3","answer":1,"chooseValue":"B"},{"id":"796238134193967105","questionId":"796238133103448065","content":" 4","answer":0,"chooseValue":"C"},{"id":"796238134210744321","questionId":"796238133103448065","content":" 5","answer":0,"chooseValue":"D"}],"userAnswer":null,"userChooseItem":null,"answerCorrect":null,"userCollect":null},{"id":"796238147296972801","title":"以下关于哈夫曼编码的叙述中，正确的是（63）。","analyze":"本题考查无损压缩技术中哈夫曼编码的基本概念。哈夫曼编码属于熵编码，是建立在信源的统计特性之上的无损压缩编码技术，按照信源符号出现的频度或概率排序后递归地自底向上建立编码树，即可得到变长信息编码。除熵编码外，词典编码也属于无损压缩编码，其基本思想是利用数据本身包含有重复代码这个特性。<br>静态图像的压缩编码可以采用无损压缩编码或有损压缩编码方法，需要视具体需求进行选择或组合多种编码方法。","multi":0,"questionType":1,"answer":"B","chooseItem":["796238148337160193"],"itemList":[{"id":"796238148324577281","questionId":"796238147296972801","content":" 哈夫曼编码是一种有损压缩方法","answer":0,"chooseValue":"A"},{"id":"796238148337160193","questionId":"796238147296972801","content":" 编码过程中需要根据符号出现的概率来进行编码","answer":1,"chooseValue":"B"},{"id":"796238148349743105","questionId":"796238147296972801","content":" 编码过程中需要建立“词典”","answer":0,"chooseValue":"C"},{"id":"796238148358131713","questionId":"796238147296972801","content":" 哈夫曼编码方法不能用于对静态图像进行压缩","answer":0,"chooseValue":"D"}],"userAnswer":null,"userChooseItem":null,"answerCorrect":null,"userCollect":null},{"id":"796238125838913537","title":"Blu-ray光盘使用蓝色激光技术实现数据存取，其单层数据容量达到了（63）。","analyze":"蓝光（Blu-ray)或称蓝光盘（Blu-ray Disc,缩写为BD)利用波长较短（405nm)的蓝色激光读取和写入数据，并因此而得名。而传统DVD需要光头发出红色激光（波长为650nm)来读取或写入数据，通常来说波长越短的激光，能够在单位面积上记录或读取更多的信息。因此，蓝光极大地提高了光盘的存储容量，对于光存储产品来说，蓝光提供了一个跳跃式发展的机会。<br>目前为止，蓝光是最先进的大容量光碟格式，BD激光技术的巨大进步，使你能够在一张单碟上存储25GB的文档文件。这是现有（单碟）DVDs的5倍。在速度上，蓝光允许1~2倍或者说每秒4.5~9兆字节的记录速度。","multi":0,"questionType":1,"answer":"D","chooseItem":["796238126811992065"],"itemList":[{"id":"796238126757466113","questionId":"796238125838913537","content":" 4.7GB","answer":0,"chooseValue":"A"},{"id":"796238126774243329","questionId":"796238125838913537","content":" 15GB","answer":0,"chooseValue":"B"},{"id":"796238126795214849","questionId":"796238125838913537","content":" 17GB","answer":0,"chooseValue":"C"},{"id":"796238126811992065","questionId":"796238125838913537","content":" 25GB","answer":1,"chooseValue":"D"}],"userAnswer":null,"userChooseItem":null,"answerCorrect":null,"userCollect":null},{"id":"796238169241571329","title":"按照国际电话电报咨询委员会的定义，媒体可以分为5类：感觉媒体、表示媒体、表现媒体、存储媒体和传输媒体。其中，(62)指进行信息输入和输出的媒体，如键盘、鼠标、扫描仪、话筒、摄像机等为输入媒体；显示器、打印机、喇叭等为输出媒体。","analyze":"本题考査的是应试者对多媒体方面的媒体分类的了解程度。<br>媒体的概念范围相当广泛，按照国际电话电报咨询委员会(Consultative Committee on International Telephone and Telegraph,CCITT)的定义，媒体可以分为如下5类。<br>(1)感觉媒体（Perception Medium):指直接作用于人的感觉器官，使人产生直接感觉的媒体。如引起听觉反应的声音，引起视觉反应的图像等。<br>(2)表示媒体（representation Medium):指传输感觉媒体的中介媒体，即用于数据交换的编码。如图像编码（JPEG、MPEG)、文本编码（ASCII、GB2312)和声音编码等。<br>(3)表现媒体（PresentationMedium):指进行信息输入和输出的媒体。如键盘、鼠标、扫描仪、话筒和摄像机等为输入媒体；显示器、打印机和喇叭等为输出媒体。<br>(4)存储媒体（Storage Medium):指用于存储表示媒体的物理介质。如硬盘、软盘、磁盘、光盘、ROM及RAM等。<br>(5)传输媒体（Transmission Medium):指传输表示媒体的物理介质。如电趣、光缆和电磁波等。","multi":0,"questionType":1,"answer":"C","chooseItem":["796238170189484033"],"itemList":[{"id":"796238170147540993","questionId":"796238169241571329","content":" 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交互性","answer":1,"chooseValue":"C"},{"id":"796238175356866561","questionId":"796238174392176641","content":" 融合性","answer":0,"chooseValue":"D"}],"userAnswer":null,"userChooseItem":null,"answerCorrect":null,"userCollect":null},{"id":"796238150421729281","title":"以下关于数据处理的叙述中，不正确的是（53）。","analyze":"数据是为应用服务的。数据解释的重要性最近得到重视，因为不同立场的人对同一批数据进行了不同的解释，会产生不同的效果。即使数据是正确的，有的人只利用其中一部分数据进行了解释；有的人利用特殊的坐标系统对数据进行图示，给人以错觉；有的人用平均数掩盖了数据中较大的差异。因此，科学合理地解释数据是数据处理工作者应具有的基本素质。<br>大批量数据处理的过程中，出现数据问题是很常见的。数据问题包括：数据的错误、数据的多余或遗漏、数据的延误、数据的混乱、对数据的非法访问（窃取或篡改）等。<br>数据处理技术包括在数据收集、输入、编辑、存储、分类、加工、统计、传输、检索、输出等各个环节中采用的技术。办公软件只是简单数据处理的常用工具，许多数据统计软件、多媒体演示系统、数据挖掘软件、联机数据处理系统、商业智能软件、决策支持系统等具有更强的功能。计算机最广泛的应用是数据处理，计算机应用基础的主要内容不应该只强调办公软件的使用方法，应该更强调数据处理各个阶段所采用的基本方法。正如农业基础不能只强调农业工具的使用。不同的观念和视野将引发教学内容的变革。<br>数据也是有生命周期的，数据从产生、存储、变更、散布、使用、备份、恢复，直到删除，不同阶段具有不同的使用频率和使用价值。现代企业的海量数据存储系统需要基于数据生命周期进行备份和处理，包括对数据安全的设计。现在，数据生命周期管理和信息生命周期管理是非常活跃的应用领域。","multi":0,"questionType":1,"answer":"C","chooseItem":["796238151357059073"],"itemList":[{"id":"796238151336087553","questionId":"796238150421729281","content":" 对正确的数据也可能做出错误的解释","answer":0,"chooseValue":"A"},{"id":"796238151348670465","questionId":"796238150421729281","content":" 软件会有故障，数据也会出现问题","answer":0,"chooseValue":"B"},{"id":"796238151357059073","questionId":"796238150421729281","content":" 数据处理技术主要指办公软件的使用方法","answer":1,"chooseValue":"C"},{"id":"796238151369641985","questionId":"796238150421729281","content":" 数据也有生命周期","answer":0,"chooseValue":"D"}],"userAnswer":null,"userChooseItem":null,"answerCorrect":null,"userCollect":null},{"id":"796238177298829313","title":"计算机对声音信号进行处理前，必须将它转换成为数字信号，最基本的声音信号数字化方法是取样-量化法。若量化后的每个声音样本用1个字节表示，则量化分辨率是(63)。","analyze":"本题考査的是应试者对多媒体方面的声音量化分辨率概念的了解程度。<br>声音信号是一种模拟信号，计算机要对它进行处理，必须将它转换成为数字声音信号，即用二进制数字的编码形式来表示声音。最基本的声音信号数字化方法是取样-量化法，它分成如下3个步骤。<br>(1)采样：采样是把时间连续的模拟信号转换成时间离散、幅度连续的信号。在某些特定的时刻获取声音信号幅值叫做采样，由这些特定时刻采样得到的信号称为离散时间信号。一般都是每隔相等的一小段时间采样一次，其时间间隔称为取样周期，它的倒数称为采样频率。采样定理是选择采样频率的理论依据，为了不产生失真，采样频率不应低于声音信号最高频率的两倍。因此，语音信号的采样频率一般为8kHz,音乐信号的采样频率则应在40kHz以上。采样频率越高，可恢复的声音信号分量越丰富，其声音的保真度越好。<br>(2) 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所谓矢量图，就是使用直线和曲线来描述的图形，构成这些图形的元素是一些点、线、矩形、多边形、圆和弧线等图元，它们都是通过数学公式计算获得的，具有编辑后不失真的特点。","multi":0,"questionType":1,"answer":"C","chooseItem":["796234705379807233"],"itemList":[{"id":"796234705321086977","questionId":"796234704348008449","content":" 像素","answer":0,"chooseValue":"A"},{"id":"796234705350447105","questionId":"796234704348008449","content":" 像素点","answer":0,"chooseValue":"B"},{"id":"796234705379807233","questionId":"796234704348008449","content":" 图元","answer":1,"chooseValue":"C"},{"id":"796234705409167361","questionId":"796234704348008449","content":" 二进制位","answer":0,"chooseValue":"D"}],"userAnswer":null,"userChooseItem":null,"answerCorrect":null,"userCollect":null},{"id":"796235426586185729","title":"<p><strong>请作答第<span style=\"color: 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