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1、letters and calls,and do practical things for the masses com bine good,effective through reaching people at the service of the last mile.Third,foster the development of new energy,new General Secretary XI Jinpi ng stressed developme nt of innovation forest restructuring,revitalization of the ol d in
2、dustrial bases in Northeast Chi na is the States major strategy,Central has issued comprehe nsive opi nions of revitalizing Northeast China and other old industrial bases,t he CPC Central Committee on revitalization in Northeast China were.Vigorous determination does not waver,the work does not slac
3、ken off.Be firm with in the devel opment has more to do with hard,and not muddle along,passive inaction.To re ly on their own efforts,cant wait,cant wait,stand still.This not only provides new opportunities for development in our region,and gave us ne w requirements.We must seize the opportunity,ful
4、l use of national policy,has to be more complicated,to start and target,give full play to theinitiative of leading ca dres at all levels,active,active,focusing on building new momentum for development,accelerating transformation of forest development.To implement the new developme nt philosophy.Phi
5、losophy is the action guide,new ideas and new developments.Carrying out innovation,coordination and development of green,open,shared ideas,must be measurable,direct action with new devel opment concepts,training ca dres.In a new development concept as a yardstick.Established in line with the new con
6、ce pt of evaluation system and evaluation criterion,embodies the new development policy,organization,mandate implementation,always measured by the new development phil osophy,continuous correction of forest transition course.In a new development concept for the path command.As part of the implementa
7、tion of the new development philosophy followed and action guideli nes,firmly adjusted,corre cted and reject unsuitable,inappropriate and even againstthe new devel opment ideas,behaviors and practices,more pragmatic approach based on a broad visi on,and creatively carry out ecol ogical construction,
8、industrial developme nt,improving pe opl es livelihood,such as the work to ensure that new development ideas take root in forest areas.In a new development concept for weapon training ca dre.Education leaders in the ne w,nothing two articles,enha nci ng vitality and power.Combined development six bi
9、g industry,and implementation three big engineering,and create two big environment,strengthening on new developme nt,and new economy concept of learning,and grasp and usi ng,real put thought and action unified to new development concept up,at with new development concept armed himself,and guide prac
10、tice,effective do advocate innovation,and focused on coordination,a nd advocate green,a nd t hick plant open,and advance shard.Second,we must rely on Science and technol ogy affects.Tchnical innovation is the promotion of economic transformation and upgrading,quality and efficiency first power.livel
11、ihood,is related to peoples well-being and social harmony and stability.We need to protect and improve the livelihood of the people as the starting point and endi ng point of transition and improve forest peoples feeling and happi ness.To promote poverty relief and development work.Implementing pove
12、rty alleviation crucial project is a major strategic decisi on made by the CPC Central Committee,is also determined by the provincial first project,we must unify thinking and action to the requirements of the Central,provincial,resolutely win the poverty battle.The previous phase I to 18 stations,Ta
13、he,Pine Ri dge research,visited many of the poor,go,the heavier,more pressure.For poverty relief and development work,we must pay attention to it,always in mind,grasping hands,should not be blindly optimistic,there can be no slack.Poverty alleviation and development lies in precise,accurate.Present,
14、in order to find out the real base of poor people as soon as possible,come up with feasible poverty standards,state card,built on t he basis of document management.To firmly establish the poverty reduction concept,increase the intensity of resource integration,and related funding,with limited funds
15、wisely.By usi ng a combination of employment,entrepreneurship for poverty eradication poverty eradication,education,poverty alleviation,medical aid of poverty means,due to effects of policies,those policies,ensure the completion of mission objectives for poverty eradication for the year.To actively
16、promote the constructi on of new towns.In February this year,promulgated by the State Council on further promoting urbanization construction of new opi nions,proposed to adhere to the people-centered,four modernizati ons synchronization,optimization,e col ogy civilization and cultural heritage of ne
17、w urbanization path with Chi nese characteristics.A ccording to district-wi de construction of civilized city and the beautiful countryside,further strengthe ning of urban transport,water supply and drainage and sewage,waste disposal ground,underground,such as infrastructure construction,strive to c
18、reate a safer and more livable environment.To actively seize the full stop and opportunities for poverty alleviation and development,further efforts to increase forest villages merge,population to the County(district)Council sites and centres concentrated in villages and towns.Combined developme nt
19、of urban construction and t ourism industries,careful planni ng and construction of a number of suitable for residential and farm tour towns and villages,forming one village one product,a feature pattern.Closer to the masses.Since last year,our in-depth implementation of the leading ca dres of grass
20、roots masses at work,solve the pr oblems of a large number of people,get the masses give wholehearted support to and praise,this work will carry on,absolutely cannot or movement.Grassroots masses and cadres in combination with poverty reduction,combined with the steady work of数字视频的基本概念（一）电视的实现，不仅扩大和
21、延伸了人们的视野，而且以其形象、生动、及时的优点提高了信息传播的质量和效率。在当今社会，信息与电视是不可分割的。多媒体的概念虽然与电视的概念不同，但在其综合文、图、声、像等作为信息传播媒体这一点上是完全相同的。不同的是电视中没有交互性，传播的信号是模拟信号而不是数字信号。利用多媒体计算机和网络的数字化、大容量、交互性以及快速处理能力，对视频信号进行采集、处理、传播和存储是多媒体技术正在不断追求的目标。可以说视频是多媒体的一种重要媒体。与视频有关的名词如下：视像（visual image）：电视信号或录像带（videotape）上记录的连续的图像。伴音（audio）：伴随视像的声音信号。数字视频
22、（digital video）：包括运动图像（visual）和伴音（audio）两部分。一般说来，视频包括可视的图像和可闻的声音，然而由于伴音是处于辅助的地位，并且在技术上视像和伴音是同步合成在一起的，因此具体讨论时有时把视频（video）与视像（visual）等同，而声音或伴音则总是用audio表示。所以，在用到“视频”这个概念时，它是否包含伴音要视具体情况而定。本章首先介绍模拟视频信号的基本概念，然后介绍视频信号的数字化标准，数字视频的几种主要格式MPEG、AVI 和 MOV，以及格式间的转换。模拟电视制式及信号电视系统是采用电子学的方法来传送和显示活动景物或静止图像的设备。在电视系统中，
23、可以说视频信号是连接系统中各部分的纽带，其标准和要求也就是系统各部分的技术目标和要求。电视的发展前景是数字彩色电视，数字视频系统的基础是模拟视频系统，而彩色电视又是在黑白电视的基础上发展起来的。黑白电视信号一、电视原理：电视同样也是采用动画的视觉原理构造而成的，其基本原理为顺序扫描和传输图像信号，然后在接收端同步再现。电视图像扫描是由隔行扫描组成场，由场组成帧，一帧为一幅图像。定义每秒钟扫多少帧为帧频；每秒钟扫描多少场为场频；每秒钟扫描多少行为行频。二、场频和帧频：我国的电视画面传输率是每秒25 帧、50 场。25Hz的帧频能以最少的信号容量有效地满足人眼的视觉残留特性；50Hz 的场频隔行扫
24、描，把一帧分成奇、偶两场，奇偶的交错扫描相当于有遮挡板的作用。这样，在其它行还在高速扫描时，人眼不易觉察出闪烁，同时也解决了信号带宽的问题。由于我国的电网频率是50Hz，采用 50Hz 的场刷新率可以有效地去掉电网信号的干扰。三、全电视信号：电视信号中除了图像信号以外，还包括同步信号。所谓同步是指摄像端（发送端）的行、场扫描步调要与显像端（接收端）扫描步调完全一致，即要求同频率、同相位才能得到一幅稳定的画面。一帧电视信号称为一个全电视信号，它又由奇数场行信号和偶数场行信号顺序构成。四、分解率：电视的清晰度一般用垂直方向和水平方向的分解率来表示。垂直分解率与扫描行数密切相关。扫描行数越多越清晰、
25、分解率越高。我国电视图像的垂直分解率为575行或称 575 线。这是一个理论值，实际分解率与扫描的有效区间有关，根据统计，电视接收机实际垂直分解率约400 线。水平方向的分解率或像素数决定电视信号的上限频率。最复杂的电视图像莫过于黑白方块交错排列的图案，而方块的大小由分解率决定。根据这种图案，可以计算出电视信号逐行扫描时的信号带宽约为10MHz；而隔行扫描时的信号带宽约为5MHz。我国目前规定的电letters and calls,and do practical things for the masses com bine good,effective through reaching pe
26、ople at the service of the last mile.Third,foster the development of new energy,new General Secretary XI Jinpi ng stressed developme nt of innovation forest restructuring,revitalization of the ol d industrial bases in Northeast Chi na is the States major strategy,Central has issued comprehe nsive op
27、i nions of revitalizing Northeast China and other old industrial bases,t he CPC Central Committee on revitalization in Northeast China were.Vigorous determination does not waver,the work does not slacken off.Be firm with in the devel opment has more to do with hard,and not muddle along,passive inact
28、ion.To re ly on their own efforts,cant wait,cant wait,stand still.This not only provides new opportunities for development in our region,and gave us ne w requirements.We must seize the opportunity,full use of national policy,has to be more complicated,to start and target,give full play to theinitiat
29、ive of leading ca dres at all levels,active,active,focusing on building new momentum for development,accelerating transformation of forest development.To implement the new developme nt philosophy.Phi losophy is the action guide,new ideas and new developments.Carrying out innovation,coordination and
30、development of green,open,shared ideas,must be measurable,direct action with new devel opment concepts,training ca dres.In a new development concept as a yardstick.Established in line with the new conce pt of evaluation system and evaluation criterion,embodies the new development policy,organization
31、,mandate implementation,always measured by the new development phil osophy,continuous correction of forest transition course.In a new development concept for the path command.As part of the implementation of the new development philosophy followed and action guidelines,firmly adjusted,corre cted and
32、 reject unsuitable,inappropriate and even againstthe new devel opment ideas,behaviors and practices,more pragmatic approach based on a broad visi on,and creatively carry out ecol ogical construction,industrial developme nt,improving peopl es livelihood,such as the work to ensure that new development
33、 ideas take root in forest areas.In a new development concept for weapon training ca dre.Education leaders in the ne w,nothing two articles,enha nci ng vitality and power.Combined development six big industry,and implementation three big engineering,and create two big environment,strengthening on ne
34、w developme nt,and new economy concept of learning,and grasp and usi ng,real put thought and action unified to new development conce pt up,at with new development concept armed himself,and guide practice,effective do advocate innovation,and focused on coordination,a nd advocate green,a nd thick plan
35、t open,and advance share d.Second,we must rely on Science and technol ogy affects.Tchnical innovation is the promotion of economic transformation and upgrading,quality and efficiency first power.livelihood,is related to peoples well-being and social harmony and stability.We need to protect and impro
36、ve the livelihood of the people as the starting point and endi ng point of transition and improve forest peoples feeling and happi ness.To promote poverty relief and development work.Implementing poverty alleviation crucial project is a major strategic decisi on made by the CPC Central Committee,is
37、also determined by the provincial first project,we must unify thinking and action to the requirements of the Central,provincial,resolutely win the poverty battle.The previous phase I to 18 stations,Tahe,Pine Ri dge research,visited many of the poor,go,the heavier,more pressure.For poverty relief and
38、 development work,we must pay attention to it,always in mind,grasping hands,should not be blindly optimistic,there can be no slack.Poverty alleviation and development es in precise,accurate.Present,in order to find out the real base of poor people as soon as possible,come up with feasible poverty st
39、andards,state card,built on t he basis of document management.To firmly establish the poverty reduction concept,increase the intensity of resource integration,and related funding,with limited funds wisely.By usi ng a combination of employment,entrepreneurship for poverty eradication poverty eradicat
40、ion,education,poverty alleviation,medical aid of poverty means,due to effects of policies,those policies,ensure the completion of mission objectives for poverty eradication for the year.To actively promote the constructi on of new towns.In February this year,promulgated by the State Council on furth
41、er pr omoting urbanization construction of new opi nions,proposed to adhere to the people-centered,four modernizati ons synchronization,optimization,e col ogy civilization and cultural heritage of new urbanization path with Chi nese characteristics.A ccording o district-wide construction of civilize
42、d city and the beautiful countryside,further strengthe ning of urban transport,water supply and drainage and sewage,waste disposal ground,underground,such as infrastructure construction,strive to create a safer and more livable environment.To actively seize the full stop and opportunities for povert
43、y alleviation and development,further efforts to increase forest villages merge,population to the County(district)Council sites and centres concentrated in villages and towns.Combined developme nt of urban construction and t ourism industries,careful planni ng and construction of a number of suitabl
44、e for residential and farm tour towns and villages,forming one village one product,a feature pattern.Closer to the masses.Since last year,our in-depth implementation of the leading ca dres of grassroots masses at work,solve the pr oblems of a large number of people,get the masses give wholehearted s
45、upport to and praise,this work will carry on,absolutely cannot or movement.Grassroots masses and cadres in combination with poverty reduction,combined with the steady work of视图像信号的标称频带宽度为6MHz，根据带宽，可以反推出理论上电视信号的水平分解率约 630 线。五、伴音：音频信号的频率范围一般为20Hz 20KHz，其频带比图像信号窄得多。电视的伴音要求与图像同步，而且不能混迭。因此一般把伴音信号放置在图像频带以
46、外，放置的频率点称为声音载频，我国电视信号的声音载频为6.5MHz，伴音质量为单声道调频广播彩色电视信号一、彩色与黑白电视信号的兼容：黑白电视只传送一个反映景物亮度的电信号就行了，而彩色电视除了传送亮度信号以外还要传送色度信号。所谓黑白电视与彩色电视的兼容是指黑白电视机接收彩色电视信号时能够产生相应的黑白图像；而彩色电视机在接收黑白电视信号时也能产生相应的黑白电视图像。也即电视台发射一种彩色电视信号，黑白和彩色电视都能正常工作。二、兼容的实现：1.在彩色电视信号中首先必须使亮度和色度信号分开传送，以便使黑白电视和彩色电视能够分别重现黑白和彩色图像。用YUV 空间表示法就能解决这个问题。采用YU
47、V 空间还可以充分利用人眼对亮度细节敏感而对彩色细节迟钝的视觉特性，大大压缩色度信号的带宽。我国规定的亮度信号带宽为6MHz，而色度信号U、V 的带宽分别仅为1.3MHz。色度信号的高频分量几乎都被压缩掉了，如果仅靠两个1.3MHz的色信号来反映图像细节将会使图像模糊，界限不清楚。实际上由于亮度信号具有6MHz的带宽，其细节是很清晰的，用它完全可以补偿色度信号缺少高频分量的缺陷。这种用亮度信号来补偿色度信号高频不足的方法称为高频混合法，它类似于大面积着色原理，图像细节完全依靠黑白细节来满足。2.尽量压缩彩色电视信号的频带宽度，使其与黑白电视信号的带宽相同。为了解决信号频带的兼容问题，采用频谱交
48、错的方法，把两个1.3MHz的色度信号频谱间插在亮度信号频谱的高端，这是因为亮度信号的频谱高端信号较弱，而且间隔较大。这样既不增加6MHz的带宽，又不会引起亮度和色度信号的混乱，而且也不会与伴音信号混叠。3.除了新设置的色同步信号以外，应采用与黑白电视信号完全一致的行、场扫描以及消隐、同步等控制信号。色度的同步信号是叠加在行消隐脉冲之上，这样可以保证彩色电视与黑白电视的扫描和同步完全一致。黑白电视在接收到彩色全电视信号以后，可从中获取黑白电视信号，实现彩色电视与黑白电视的兼容。数字视频的基本概念（二）彩色电视的制式电视信号的标准也称为电视的制式。目前各国的电视制式不尽相同，制式的区分主要在于其
49、帧频（场频）的不同、分解率的不同、信号带宽以及载频的不同、色彩空间的转换关系不同等 等。世 界 上 现 行 的 彩 色 电 视 制 式 有 三 种：NTSC（National Television System Committee）制（简称N 制）、PAL（Phase Alternation Line）制和 SECAM 制。彩色电视国际制式TV 制式NTSC M PAL D SECAM 帧频（Hz）文档编码:CV1C1X7O8P4 HQ8Z3I10S2M10 ZV6Z3O8I8E2文档编码:CV1C1X7O8P4 HQ8Z3I10S2M10 ZV6Z3O8I8E2文档编码:CV1C1X7O8P
50、4 HQ8Z3I10S2M10 ZV6Z3O8I8E2文档编码:CV1C1X7O8P4 HQ8Z3I10S2M10 ZV6Z3O8I8E2文档编码:CV1C1X7O8P4 HQ8Z3I10S2M10 ZV6Z3O8I8E2文档编码:CV1C1X7O8P4 HQ8Z3I10S2M10 ZV6Z3O8I8E2文档编码:CV1C1X7O8P4 HQ8Z3I10S2M10 ZV6Z3O8I8E2文档编码:CV1C1X7O8P4 HQ8Z3I10S2M10 ZV6Z3O8I8E2文档编码:CV1C1X7O8P4 HQ8Z3I10S2M10 ZV6Z3O8I8E2文档编码:CV1C1X7O8P4 HQ8Z