So many times I see a guy video calling another crew across the country and it can take a solid 5-10 seconds before we hear them reply. I’ve seen kids in siberia with better ping.
In: 492
Why are you talking to kids in Siberia?
I’ll just add, as a former broadcast tech, they’re not doing a call at all like you would FaceTime somebody. The signal going to the studio, and the return from the studio typically take separate paths with all sorts of latency introduced from various broadcast equipment. Satellite, MPEG encoders/decoders, etc.
> I’ve seen kids in siberia with better ping
Whoa whoa whoa
Watching kids? What other countries are you watching kids in?
Forget satellites. A local radio station is simulcast on AM and FM. The FM is multiple seconds behind. It’s all about the encoding and processing.
Since it hasn’t been mentioned yet, one other factor in video call latency is buffering. Because videos are not sent frame by frame (but rather an occasional full “key” frame followed by a sequence of data describing only what has changed), they need to accumulate some of that data before the video can be transmitted or displayed. When the connection is poor, there is a need to increase the size of this buffer to avoid interruptions, as it is sometimes necessary to re-transmit corrupted information or temporarily reduce the transmission rate to avoid issues.
Some corporations pay top price for all in one “high end” systems with dedicated hardware that end up being old tech sprayed with a fake layer of gold that open source apps can do 10x better.
This is a great question and there’s actually a lot more to it than most people would realise!
It all depends on how your connecting your two “locations” and understanding that broadcast has to be 100% reliable.
If we use normal public internet, there’s a lot of unknowns… And the things that affect our teams/FaceTime/etc can affect the TV call too. But the difference is rather than one person breaking up or stuttering to a few others on the call, that break up is on TV being watched by potentially millions!
So in many cases we try and work around that. The most common is by using satellites! Where your rent a frequency for the duration of your broadcast (that you and only you are meant to use) and connect to a satellite and receive it back at the studio. This means you always have a fixed amount of data with a fixed route back with a dedicated reliable connection!
The downside of satellites is that the amount of data you can send is really low for the cost… So you have to “compress” your video and audio. I could talk for hours about compression, but the key fact is that the most efficient forms of compression work by taking a whole image from your video once every second (sometime more often or less often) and for all the frames in between only transmit what’s changed since the full one.
For example if your video is a ball bouncing, you don’t need to send the whole ball every frame, you can just say, repeat the last frame and move this section of it down a bit (this is a big simplification, but close enough)
The problem with this is you need the whole second at EACH to start getting any video. Which means it will take at least 2 seconds, not including the time it takes for the data to be sent to a satellite truck, sent up to space, processed and send back down to a receiver…
In the last few years we’ve actually got much better at using the normal public internet and writing clever code to deal with dodgy connections and we are using the internet more and more for TV. It’s also possible to get your own dedicated connection put in between your locations. Many big studios and production centres have links to ISPs that are dedicated for broadcast use. For example in the UK every footballs stadium in the country has dedicated fibre run back to a hub in Milton Keynes with network hardware at every single one. So company’s like sky/BT/ITV can produce their football coverage without using satellites!
Source: Broadcast network engineer, work on things like premiere league football, Wimbledon, Olympics and more
I worked in a small tv station and did a bunch of live broadcasts – these days we’re mostly LTE based, we use devices such as liveu 600 that uses 13 different connections to send the data, it’s also encoding in HEVC which is pretty fast while giving good quality and so overall the delay is minimal, below a second. Even adding all the other gear between us and your tv it shouldn’t be much.
Where i worked the delay was mostly intentionally added at the last step so that the director could cut it in case something happened. It was funny because we were using normal phones for communication so back in the station you’d hear the reporter talking a couple of seconds before seeing it on the screens.
It’s about cost. I use Microsoft teams professionally and Discord personally. Discord has much lower ping because that is a selling point. However teams has effectively no competition and so doesnt spend the money for better servers and better client that can get the delay lower.
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