Helsinki 2007 was the first broadcast in HD, Athens was recorded in the format for test purposes but broadcast in SD everywhere. I think had the UK won a year later than they did (hosting in 1999 instead of Israel) we’d have had the first 16:9 contest a lot earlier, as May ‘98 was just that little bit too early given digital broadcasts hadn’t started yet here and absolutely nowhere in Europe was broadcasting in 16:9 as far as I know, except the occasional letterboxed movie showing in some countries.
I’m interested to know if the spokespeople during the voting are all in HD or not yet. Certainly in the late 2000s they were all 4:3 SD even in the HD era, but this wasn’t obvious on TV as they only took up a small part of the screen. I can’t find any up to date listing of what countries broadcast in HD now, has it really reached far flung places like Belarus or Armenia yet?
The voting spokespeople format remained in SD for a long time after the shows were produced in HD. It only changed to HD relatively recently, the last 5 years or so?
Similarly in recent years the voting has moved from being 'all satellite' to a mix of satellite and IP (and in some cases a mix of satellite and fibre).
I'm not very technical but is the use of IP the reason for the awkward 2-second delays during the voting sequence (and on Saturday night)? From watching the 1997 and 1998 Contest recently it was very noticeable that there were none of the awkward delays during the voting.
No - it's the switch to digital compression largely - which is a larger proportion of the delay than the satellite path.
In 1997 and 1998 analogue satellite links were used where the only appreciable delay was introduced by the speed of light time to and from the satellite (plus a 40ms frame or two of synchroniser delay).
These days h.264 compression is used whether the path is fibre, satellite or IP (which itself can be over fibre or satellite). h.264 compression works by storing a whole bunch of 40ms frames and analysing them for differences, and then coding occasional full frame pictures (I-frames) and then for the in-beteween frames just sending compressed 'difference frames' along with data that lets these be used by the deccoder to recreate the original frames. This compression means that the video is buffered by a number of frames. Usually the higher quality the compression, the more frames are buffered and analysed, and the higher the latency, or delay, that is introduced. Codecs can easily introduce a 2" delay.
Putting a second h.264 codec into the path will often double your codec delay too... (This can happen if a circuit is downlinked in one place, not the main broadcast location, decoded, and then re-encoded to be fibred to another location. Ideally you wouldn't decode en-route and just pas on the compressed stream but this isn't always possible)
h.264 (and MPEG2 before it) encoders usually have a mode called 'low latency' that either drops the quality or requires a higher bitrate (and thus a wider bandwidth satellite channel) to carry it with a reduced delay. The EBU ask for all voting uplink encoders to be in 'low latency' mode for the contest - though whether everyone does this I don't know.
For the regular contest, the other issue is that the audio that that voting spokespeople here is also carried over a compressed satellite link (it's carried as part of the incoming feed of the Eurovision Song Contest - all spokespeople listen to the same audio - which has just the show presenters - so spokespeople don't hear each other just the presenters and silence). This audio is supposed to be encoded 'unlocked' (so it isn't delayed to match the video, and just has an audio codec plus satellite speed-of-light path delay) - but I'm not sure that always happens... So there is a second delay involved with that audio getting TO the spokespeople, which you can add to the delay that the audio and video of the spokespeople going back to the contest truck also has.
I've had round trip delays of 4" on a single hop, and 8" on a double hop circuit...
With IP contributions things are complicated a bit if you use the public internet. Then you may also add some 'buffer' on top of the codec delay, to allow missed packets to be re-requested, or to cope with packets arriving out of order. This is often a setting on the IP contribution system.
My understanding is that the EBU Flex platform used for IP contributions to the Eurovision Song Contest, is based on the Mobile Viewpoint WMT product - where many people run with a 2-3" buffer delay on top of the codec delay.