I have been reading about the costs associated with live streaming and the desire to know how it was done for the World Championship finals in April 2016. Here is how it was set up:
I hope that this goes some way to moving forward with future live streaming, demonstrating that cost is not a significant issue
Ian Plummer adds:
It would seem sensible to put bounds on what limits the video and which grade of kit to purchase.
The primary bottleneck is the uploading bandwidth at the venue in question. If the camera used has 'too many pixels' it will choke the upload link. Similarly too many cameras will do the same. If the broadcast quality is higher than necessary there will be potentially bandwidth choking and a higher network cost since more data is being transferred.
A second limitation is the resolution of the device that the final images are viewed on. Even a top of the range iPhone 6 with a retina display is only reaching "2K" (its camera is however 4K).
The problem with moving to too low a resolution is that the detail is absent. If we were to fly a drone over a lawn (also for example here - turn your sound down!) with, for example, a "720p" (1280x720 pixels, 0.9M pixels) camera on it so the lawn filled the frame, then 1 pixel approximates to a square inch. This results in the balls and hoops being just 3 pixels wide. (The linked still drone pictures are higher than 720p, the streaming one can be set to 1080p ) . Drones are not ideal!
Currently the top streaming video formats use "4K" = 4096 * 3072 pixels (12M pixels); this is then compressed (H 264 compression). Lying between 720p and 4K is 1080p (1920x1080 pixels 2.1M pixels) which would probably be a good compromise. Typical bandwidths can be estimated. For example 30 fps, medium quality (34KB per frame)
720p = 3.8 Mbps
1080p = 8.2 Mbps
4K > 24 Mbps
The complexity of the image will affect the bandwidth.
If more cameras are used simultaneously the bandwidth requirement is summed. Most network packages offer high download speeds and an upload speed which is a fraction of that. In the UK I got 6Mbps upload for 100Mbps download which went up to 10Mbps upload on 150Mbps download (from Virgin). It is possible however to rent network bandwidth for special events. The catch is they generally want you to purchase in months not days.
Although wireless networking is ubiquitous it is naff. The wireless signal is easily masked by big bags of water (humans moving around), trees, microwave cookers, wireless telephones (DECT in the UK) and other wireless routers. For a fully reliable video stream cabled network connections would be a bonus. For standard network cables (Cat5) there is a recommended maximum length of 100 metres (~330 feet or 3 lawn lengths). Network cables are however trip hazards and can be a source of power (Power Over Ethernet - POE), which could be worrying in rain or thunderstorms.
To allow many people to view the video a single upload stream is sent to a big server on the internet and the viewers get their video feed from that server which acts as a relay. There are a number of companies which will do that - livestream was used for the 2016 Worlds
If standard cameras are being used, then their battery life becomes an issue. Upmarket "IP cameras" would offer the option of taking their power through the network cable.