NDI Bridge, SRT and vMix in the Cloud (Chapter 11)

From the far end of an NDI Bridge connection, the same outside IP address and port number information is necessary to send video. Once both ends of the NDI Bridge are connected, the NDI sources available on the host side will be made available for the far end side to use just like local NDI sources. 

NDI Bridge supports NDI video source capabilities including alpha channel, PTZ controls, KVM, Tally, and Metadata. Alpha channel support is necessary for many broadcast graphics applications. Graphics overlays are a use case for NDI Bridge used with alpha channel video. Alpha channel video supports a transparent background that  overlays on top of another video source. In this way, NDI Bridge allows remote productions to bring alpha channel graphics into a production environment from anywhere in the world. 

PTZ camera controls open up another interesting use case in which NDI Bridge is used to send video from a PTZ camera where the PTZ cameras can be controlled from a remote location. KVM, a popular abbreviation for “Keyboard, Video, and Mouse” can be used to pass along remote controls for computer screens captured with KVM support. 

NDI Bridge will also maintain support for Tally,  the technology that alerts camera operators and on-screen talent when a camera is in use. This is an interesting feature which would allow a remote production to know when a specific NDI video source is being used even from a remote production. The Tally feature of NDI will be discussed in more detail in Chapter 19. Finally, some metadata is also transported over the NDI Bridge which includes information such as NDI source-friendly names. Metadata makes NDI video more usable by providing information that compatible NDI systems can use to display relevant information to producers working with the video.

While NDI Bridge does have some technical requirements before it can work, it provides powerful connectivity options. In comparison to established wide area network (WAN) video transport solutions like Secure Reliable Transport (SRT), NDI simplifies set-up by requiring  a single port to support multiple video channels. NDI Bridge provides the opportunity for many productions to think outside of their own local area networks (LAN) to implement video projects that incorporate video from around the world. 

NDI Bridge in Virtual Environments

Using NDI Bridge in a Virtual Machine (VM) offers a host of benefits for producing high-quality live events, particularly in optimizing resource efficiency, enhancing flexibility, improving performance, providing redundancy, and ensuring both security and ease of maintenance. By running NDI Bridge in a VM, precise allocation of necessary resources is enabled, freeing up additional resources for other tasks and optimizing overall hardware utilization.

VMs significantly enhance the flexibility of managing software configurations. They facilitate easy switching between setups and simplify the process of creating backups and replicating systems—key advantages in dynamic production environments. When VMs support Graphics Processing Unit (GPU) passthrough, this feature can dramatically improve the performance of NDI Bridge by harnessing the GPU’s capabilities for intensive video processing tasks such as encoding and decoding, which are crucial for real-time streaming.

Furthermore, operating NDI Bridge within a VM environment enables the maintenance of multiple instances, providing critical redundancy and ensuring backup instances are ready to deploy in case of system failure, thus enhancing the reliability of live productions. VMs also bolster the overall stability and security of the operating environment; by isolating NDI Bridge within a VM, any potential crashes or errors are confined to the VM itself, minimizing the risk to the entire system. Security issues within the VM are similarly contained.

In terms of maintenance, VMs make it easier to isolate problems and perform system troubleshooting. Should issues arise with NDI Bridge, the system can be quickly restored to a previous state, or a new VM can be set up without affecting the main operating system.

However, it’s important to acknowledge the potential drawbacks. Running NDI Bridge in a VM introduces additional complexity and overhead, and setting up GPU passthrough might be challenging depending on the specific hardware and software environment. These factors should be carefully weighed against the needs and constraints of the specific production environment to determine if using NDI Bridge in a VM is the most suitable approach.