主码流和子码流的区别？如何快速的计算监控存储量

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>最近有不少朋友在问到关于子码流与主码流的区别？为啥监控老是卡顿？如果快速的计算监控硬盘容量等问题，本期我们一起来看下相关内容。

一、主码流与子码流的区别

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>海康威视首家提出了主码流与子码流这样的概念，是为了解决在网络情况不好时为了满足远程预览的流畅性降低码率，而不影响本地录像提出的双码流技术，即一路视频进入NVR后，NVR可以编码提供两种码流，主码流和子码流，主码流分辨率高于子码流，主码流用来录像，子码流用来网传。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>这就叫双码流技术。目的是用于解决监控录像的本地存储和网络传输的图像的质量问题。

090431171

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>双码流能实现本地和远程传输的两种不同的带宽码流需求，本地传输可以用主码流，能获得更清晰的存储录像，远程传输就因为带宽限制的原因，而使用子码流来获得流<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>畅的图像和录像。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>当一路视频进入录像机后，录像机可以编码提供了主码流和子码流两种码流，主码流用来本地录像，子码流用来网络传输。默认是录像机本地访问，自动主码流显示。远程访问自动子码流显示，所以当你<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>远程监控访问时出现卡<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>顿<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>，可以尝试通过降低子码流来解决。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>主码流一般码流较大，清晰度高，占用的带宽也就高。子码流在主码流的图像环境下降低了图像格式，清晰度较主码流要低，占用带宽小。主码流一般用于存储，子码流用于网传。主码流本地存储，子码流适用于图像在低带宽网络上传输。

<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”><span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>这样做的目的是<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>当我们用子码流预览时<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>如<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>果网<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>络状况不是很好，可以<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>降低子<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>码流的码率<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>（随着位率的降低画质会<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>有降<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>低），以达到改善网络浏览的流<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>畅性，而又不<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>改变本地<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>录像的录像效果。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>知道了上述理论，就可以明白为什么老是有人在问这样的问题：
<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>为什么视频监控使用子码流图像模糊？

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>为什么网络摄像机一用主码流就拖屏，子码流就没问题？

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>主码流是最高像素分辨率模式，次码流是低像素低分辨率模式。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>选择主码流时，画质高，对带宽要求也高，如出现画面拖屏或者出现断层卡画面就是<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>网络传输不过来，这样的情况解决办法：

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>1、选择子码流，低画质，提高画面传输的流畅度

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>2、在设置后台，将码流对应的帧率调低，分辨率调低，这样可以降低带宽需求。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>3、提高网络带宽，满足高画质传输需求。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>上面我们已经了解了主码流与子码流的区别了，那么如何来计算一个摄像头一天的存储量呢？这个其实是一个常谈的问题，仍然有不少朋友在我们弱电行业网后台留言问到，这里面我们再来总结式的了解下，找个快速易记的方法。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>摄像机的码流即监控视频流的带宽，分为主码流和子码流，主码流用来存储，子码流一般用来预览，所以录像回放时大家看到的视频质量要高于预览时看到的。在不同分辨率/帧率以及画面效果时码率大小有所差异。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>由于编码压缩算法的不同，H.264<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>和H.265码流不同。<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>目前主流编码为H.265，相比H.264可节省将近一半的传输带宽和存储占用量。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>硬盘容量，即硬盘的存储空间大小，一般有1T/2T/3T/4T/6T，1T=1024G，1G=1024M。需要注意的是，硬盘实际可用于存储视频的容量为总容量的90%，即容量系数为0.9，为什么呢？

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>因为：硬盘厂家的标准是十进制，因此 1G=1000MB=1000000K，而系统的采用的是二进制，所以1G=1024MB=1048576KB。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; color: rgb(217, 33, 66);”>录像存储大小=主码流(M)÷8×3600(秒)×24(小时)×监控通道数×录像天数

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>假设某项目的高清头是H.265格式1080P(主码流约3M)，50路，存储90天，那么计算公式如下：

<span style="margin: 0px; padding: 0px; max-width: 100%; font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; box-sizing: border-box !important; overflow-wrap: break-word !important;”>3M(主码流)÷8×3600(秒)×24(小时)×50(监控通道)×90(录像天)≈145800000MB

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>换算为T则为：145800000MB÷1024÷1024≈139T，按硬盘实际容量90%则为：139T÷0.9=154.4T，即您需要总共154T的硬盘才可以满足存储需求，那么取个整就按160T准备吧。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1; color: rgb(217, 33, 66);”>备注下：

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>主码流÷8，我们所说的监控码流是以比特(bit)为单位。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; letter-spacing: 0.544px; text-align: start; text-indent: 34px; widows: 1;”>当然，现在计算有各种计算器，都可以直接计算，不过平时在项目中，可以快速的预估下更好。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; letter-spacing: 0.544px; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; text-align: start; text-indent: 34px; widows: 1;”>960P实际是指分辨率1280×960，相当于130万像素：

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; letter-spacing: 0.544px; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; text-align: start; text-indent: 34px; widows: 1;”>H.265存储一天22G左右（一小时1G）。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; letter-spacing: 0.544px; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; text-align: start; text-indent: 34px; widows: 1;”>1080p实际是指分辨率1920×1080像素，相当200万像素：

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; letter-spacing: 0.544px; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; text-align: start; text-indent: 34px; widows: 1;”>H.265存储一天32G左右（一小时1.3G）。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; letter-spacing: 0.544px; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; text-align: start; text-indent: 34px; widows: 1;”>3mp实际是指分辨率2048*1536像素，相当于300万像素：

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; letter-spacing: 0.544px; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; text-align: start; text-indent: 34px; widows: 1;”><span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; letter-spacing: 0.544px; box-sizing: border-box !important; overflow-wrap: break-word !important;”>H.265存储一天<span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; letter-spacing: 0.544px; box-sizing: border-box !important; overflow-wrap: break-word !important;”>45G左右（一小时1.9G）。

<span style="margin: 0px; padding: 0px; max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important; letter-spacing: 0.544px; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; font-size: 15px; text-align: start; text-indent: 34px; widows: 1;”><span style="margin: 0px; padding: 0px; max-width: 100%; color: rgb(62, 62, 62); font-family: Optima-Regular, PingFangTC-light; letter-spacing: 0.544px; box-sizing: border-box !important; overflow-wrap: break-word !important;”>4mp、5mp、8mp对应的就是400万、500万、800万像素，这里就不说，大家可以自己看上表。