Livestreaming Video with NDI and PTZ

Producing and delivering live-streamed video is now more affordable and accessible than ever before. With NewTek’s Network Device Interface (NDI) technology and remotely controlled pan-tilt-zoom (PTZ) cameras, it’s even easier to set up and operate complex productions with minimal staff requirements.

Traditional live production setups can require miles of cables to each camera, radio headset systems, and at least one person for each camera. NDI connectivity and PTZ cameras enable a producer to minimize cable requirements while enhancing opportunities for creativity in camera placement and use. A setup like this can do more with less, and it gives us a glimpse into what the future of live production could look like.

Definitions and Details

So, what is NDI? San Antonio, Texas-based NewTek, developer of the TriCaster live production system, unveiled NDI at IBC in 2015, making it a relatively new technology. In a nutshell, NDI allows a user to utilize existing gigabit network infrastructure to connect a wide range of devices together through standard ethernet cables and ports. Since many PTZ cameras are now offered with Power over Ethernet (PoE), this also means that control, signal, and power can flow through a single cable rather than three. NDI uses the multicast Domain Name System (mDNS) discovery standard to broadcast and locate sources across a network. Once sources are set up on the switcher, there is video, uncompressed audio, and metadata being sent from each source. Typically, cameras will be sending a 1080i signal with variable bitrate around 100Mbps. NewTek’s newest TriCaster, the TC1 (Figure 1, below), can handle 4K at 60p.

Figure 1. The NewTek TriCaster TC1

NDI-compatible equipment is available from a wide array of manufacturers, although NewTek offers the most options. The company sells cameras, converters, live production systems (such as the TriCaster series), graphics packages, and other tools and accessories. Many other manufacturers including PTZOptics (Figure 2, below), Streambox, Panopto, Magewell, vMix, Panasonic, and Marshall all offer a range of NDI gear such as cameras and converters. Converters such as the NewTek Connect Spark ensure that even existing or older camera systems don’t have to be replaced in order to take advantage of NDI. Producers can convert HDMI, SDI, and even 4K UHD cameras at the camera and add them to the list of available sources on the network.

Figure 2. The 2018 Streaming Media Readers’ Choice Award-winning PTZOptics 20X-SDI

The most important aspect of NDI is that it is available to anyone with a royalty-free license. NewTek even maintains an SDK that’s compatible with mobile, Windows, Linux, and macOS. Software developers and hardware manufacturers can integrate NDI into their products at zero up-front or ongoing cost.

PTZ is a relatively old technology that most producers are already familiar with. Even so, the camera systems that could be classified as PTZ have exploded and blurred the lines in recent years. At its core, a PTZ camera is the typical dome or lens-on-a-stick style like you see in many houses of worship and small- or medium-sized conference rooms. These compact systems are quite capable for most scenarios. They’re powered either by wall plug or ethernet cable and can be placed nearly anywhere either permanently or temporarily. Image-flipping for inverted-ceiling installations, IP control, and long optical zooms are commonplace features among all manufacturers. For the vast majority of live production setups, the basic PTZ camera is adequate.

One might argue that there are other PTZ cameras available to producers that don’t fit the standard definition. For example, drones are increasingly being added to live shoots to provide a unique angle. In the auto-racing world, the National Hot Rod Association’s 2018 Dodge Mile-High NHRA Nationals production included a DJI drone in its mix. There was also a camera positioned on the track against a side wall. No doubt, the camera on the track was something cheap in case it was destroyed by a stray top fuel dragster, but a PTZ camera could easily have replaced it and added interest with the ability to follow the cars as they passed. Even newer systems like Spidercam and FlyLine share the capabilities of PTZ cameras while also having the advantage of long-range travel by cable.