May 8, 2020
By Anthony Burokas Principal, IEBA Communications
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All In On NDI

Networked video is the next wave in production. IP video is part of the ATSC 3.0 specification for broadcast delivery, 因此，在广播链的任何地方都无法逃避从视频信号到数据包的迁移.

Network Device Interface (NDI), developed by NewTek, is a standard that enables the use of high-quality, low-latency video on existing and standard IP networks. With NDI, 视频变成了可以使用现成的计算机网络硬件在网络上共享的数据. In the short run, this doesn’t change much, 因为你可以像使用SDI电缆一样，将以太网电缆连接到每个摄像机或转换盒. But NDI enables much more.

它可能很简单，只要把一根电缆连接到会议室的前面，然后用交换机连接到六个不同的设备, as opposed to having to run six SDI cables. 它可能像利用现有网络并在多个校园部署数十台摄像机一样复杂, all of which feed back to a central production center. This means no one needs to cart all of that gear around anymore. It also means you can call up any camera, any audio source, or any mixing device to produce any number of programs at the same time.

Moreover, this capability extends to the internet itself. 制作人可以利用另一个城市的图像艺术家和来自世界各地的摄像机进行现场直播，否则就需要十几辆外部广播卡车, expensive satellite time, 在生产链的各个方面都有广泛的专家来帮助它走到一起.

Case Study Lessons

今天，利用NDI可以像在你已经拥有的相机上添加一些相机上的转换器一样简单. Software-based video mixers have quickly moved to incorporate NDI, so your TriCaster, vMix, Wirecast, OBS, Livestream, etc., are all ready to add NDI sources into the mix. 还有许多转换器可以从BirdDog, NewTek, Magewell (Figure 1, below), and Kiloview. If you need a pan-tilt-zoom (PTZ) camera head, these have had NDI-enabled models available for some time already. These NDI heads also accept Power over Ethernet (PoE), so with one cable, you can have power, video, audio, camera control, and additional capability. For instance, BirdDog的软件也可以在NDI主干上提供机组人员通信(coms).

Figure 1. Magewell Pro Convert NDI to HDMI

我的任务是为通用金融的内部视频制作团队提供前瞻性的解决方案(Figure 2, below). 我们决定在TriCaster作为混频器，因为它有一个类似的操作外观和感觉的硬件视频混频器，他们已经使用. We picked the new 4K TriCaster Mini, which offers four built-in PoE ports, as well as two other Ethernet ports for networking. 每个端口都有自己的网络接口卡(NIC)，因此它们之间没有通信. While the TriCaster itself can see all of the connected devices, you’re not able to utilize the built-in PoE ports for, say, a BirdDog coms system to each camera.

Figure 2. Components of the NDI-driven rig I built for GM Financial

意识到这一点，您可能没有想到NDI的一个关键方面:它是自由的, and as limited, as any network device and network infrastructure you have in place. As a result, you need to become a lot more knowledgeable about networking, IP setup, DHCP, or manual addressing. For the traditional “plug-and-play” video pro, this is a whole other world, so moving to NDI has a bit of a learning curve. That said, the advantages far outweigh the additional understanding required.

For this kit, we bought three of Panasonic’s AG-CX350 camcorders (Figure 3, below). 这是第一批提供内置NDI功能的摄像机(需要额外购买和激活许可证)。. As networked camcorders, there’s a lot they can do, and NDI is just one networked feature, so they’re not set up to do NDI out of the box. 在你试图激活相机的NDI之前，你必须调整几个相机内的网络设置. Again, it’s not as simple as plugging in an SDI cable and getting video out.

Figure 3. The Panasonic AG-CX350

Additionally, in a corporate setting, you’ll have the further hurdle of a locked-down networking environment. This affected us as soon as we turned on our TriCaster Mini. 我们必须注册许可证才能使用TriCaster. To do that required an internet connection. 我们不能把TriCaster直接插进通用金融的以太网络，因为它不是一种被批准的设备. 为了公司内部所有设备的安全和保护，未知设备什么都得不到. 我知道其他公司不得不把他们的TriCaster送到IT部门，在机器上安装公司软件，这样他们就可以插入公司网络进行互联网连接. 这种公司软件可能对工具的性能产生不利影响.

我们通过将智能手机的USB连接到新买的路由器上，成功激活了我们的路由器, 然后共享与TriCaster和其他连接设备的连接. This is key, 因为获得松下相机的NDI许可还需要不受限制地连接到互联网.

您需要一台带有NDI工具和NDI Studio Monitor的计算机才能通过您自己的局域网(LAN)访问松下. Then, when you click the Register button, it will take you to the NewTek online store, where you can purchase the NDI license. Next, in NDI Studio Monitor, 导航到CX350的窗口并在那里输入激活码. It will again reach across the internet to reverify everything. 现在你的相机被激活了，可以在没有互联网连接的情况下传输NDI视频.

结论是，您应该准备好花一些时间在任何新的依赖网络的工具上进行初始设置. 有一个直接连接到外部互联网，以便让你的设备设置在你的内部网内工作.