Networking and Hardware
Network and hardware considerations:
- The upload bandwidth for the encoding/Host Site and the download bandwidth for the decoding/Remote Site should meet or exceed 2.5x the total encoding bitrate (video + audio). For example, if the encoding video bitrate is 2,000 Kb/s and the encoding audio bitrate is 128 Kb/s, the respective upload and download bandwidths available to the encoder or decoder should consistently meet or exceed 5,320 Kb/s (5.2 Mb/s).
- Consider the pros and cons between the different types of Internet Service Provider (ISP) connections when deciding which to use at your sites. Fiber connections have the highest bandwidth capability, but may be prohibitively expensive or unavailable in the area. Satellite is versatile in more locations, but it can be susceptible to snow/rain fade thus causing reduced bandwidth. Cable internet speeds can vary based on local/neighborhood traffic. DSL might be slower but the speed is more consistent than cable. Cellular connections are wireless and thus susceptible to radio frequency interference, plus more connections to the tower can reduce available bandwidth. The most reliable solution will be a combination of multiple ISP connections paired with a multi-wan router. A multi-wan router can be configured to use terrestrial (land based) network(s) as a primary, with cellular as a failover.
- Be cautious of other internet-connected applications on the network. File-syncing applications such as Google Drive & Dropbox can consume the entire bandwidth (upload and/or download) available.
- Setup QoS rules on the network to give encoder and decoder traffic a high priority. If applicable, limit the bandwidth of any guest network to reserve enough for the encoder or decoder (2.5x the encoding bitrate).
- Disable “Captive Portals”/Web Credential requirements for encoders and decoders. These types of authorization methods can timeout and interrupt the stream’s download and upload, causing problems which may go unnoticed until a critical problem has arisen.
- Always use a wired network connection for streaming, it is never recommended to stream over wireless when avoidable. If you are using a cellular hotspot as a backup connection, ensure your hotspot is either connected to a multi-wan router or wired directly to your computer via ethernet or USB.
- Always use an uninterruptible power supply (UPS) to power network equipment, the encoder, and the decoder.
- After starting the encoder (once the encoder status has changed from “Starting” to “Started”) you should verify that a new event has been created and the stream is working properly. Checking this early on will give ample time to work through any issues. This check can be made from the encoding site by using a a local decoder; if an E2000 series encoder is being used, the decoder can pull content directly from the encoder (via LAN-mode) without a trip to the internet.
- Often it is helpful for the Remote Site to have a pre-event sound check. Ask your talent to speak long enough not only for the Host Site sound check, but also for the Remote Site. Consider setting a Video Cue for the sound check so the Remote Site can easily find it in the event.
- Always keep the application up to date. The application will automatically check for updates upon launch, and can also be viewed in the “About” tab while logged in.
- Disable Wi-Fi & Bluetooth; turn on Airplane Mode to be sure Multisite Player is using a wired connection.
- Do not install remote desktop software on the playback hardware, or any other application with the intention of running it in the background during playback. Doing so may cause choppy playback as well as other network issues.
- Train volunteers on the nature of a “Production System” — they should not install any applications or make any system changes unless checking with a technical director, even if they think it is in the best interest of the production.
- Always have a backup plan should the network fail. This could be a pre-recorded video or a speaker familiar with the message.
- Discuss the backup plan with the team and always be ready to implement it. Regularly practice switching to the backup during rehearsals.
- It is generally safest to replay the 1st service unless there is conflicting content. Always consider the risk of going live during the second service vs the added benefit of being live if there are no content changes.
Progressive vs Interlaced Signals
But interlaced video comes with real-world downside, including image softening that occurs during fast-motion sequences as well as moire or strobing artifacts that sometimes appear when striped shirts, plaid jackets, bricks in a building, or similar types of objects are shown. If interlaced video needs to be compressed (which is required for real-time video streaming), the compression algorithms become very inefficient. While all legacy analog video standards use interlacing, new video compression standards like High Efficiency Video Coding (HEVC) and all video resolution standards above 1080 do not even support it.
Progressive video, on the other hand, is made up of complete video frames that contain all of the horizontal lines that make up the image being shown. As a result, images appear smoother, fast-motion sequences are sharper and artifacts are much less prevalent. All digital, non-CRT displays are natively progressive; any interlaced video signals they receive must be internally or externally converted, or “de-interlaced”, to the progressive format before they can be displayed. This de-interlacing process can be very destructive to the overall image quality. For these reasons, the Multisite Platorm is a completely progressive-based system. All signals transported over the platform need to be progressive. If an interlaced signal is provided to the encoder, the signal will be internally de-interlaced before compression occurs. Living As One recommends providing a progressive video signal throughout your entire workflow if possible, but if necessary the system can accommodate interlaced signals.
For more information, please review Chris Pirazzi’s technical documentation about fields and interlacing on Lurker’s Guide to Video website.