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Comment by toast0 | Hacker News Reader

> What's the value proposition for a consumer to go get one of these things? Obviously it won't be because of the new and exciting frontier of advertising it enables, what's the actual headline feature?

Higher video quality. Denser channel encoding gets you more bits, h.265 instead of mpeg-2 gets you better quality per bit, and new standards allow broadcasting 1080p and 2160p. More capable audio codec and more bandwidth for audio too.

I don't think direct consumer demand is going to be that high though. But, eventually manufacturers will put them in some tvs, and then it becomes a checkbox item and everybody needs them. Also, broadcasters don't want to do ATSC 1 and 3 forever (and don't have spectrum for that anyway, cell phones keep taking channels), so if there's adoption, ATSC 1 programming is going to get squeezed into fewer physical channels and quality will get worse.

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Higher video quality is and may remain hypothetical: they seem to currently be using the bandwidth for extra channels. I think you can count the number of ATSC 3 UHD broadcasters on zero fingers. You'd think the demand would be there for UHD sports, but sports is a monopoly, so :shrug:.

Like I said upthread, it's not practical for me to use the ATSC 3.0 broadcasts, so I don't have a real opinion on video quality; but hypothetical quality is a selling point. I don't recall the quality being significantly better or worse than ATSC 1, but I was more focused on if audio worked at all, and unfortunately it generally didn't because of codec problems.

From RabbitEars listings [1], it looks like markets currently have 0-2 ATSC 3 broadcasts, and in many market, those broadcasts are the basically .1 subchannels from the major ATSC broadcasts. But I do see a lot of 1080p instead of 1080i, so maybe (but if the source is 1080i and just deinterlaced at the studio instead of the receiver, meh). If they can fit 4-5 subchannels at acceptable quality in one physical channel, that is a significant increase in quality, which is consistent with roughly 2x the bandwidth and the codec upgrade.

There's a lot of chicken and egg here. Can't use more bandwidth for better quality if you only have spectrum to do a demo with all the local broadcasters. Don't want to bother with getting 4k content piped through the broadcast chain if nobody actually receives it, and you have to downconvert it to send over ATSC 1 anyway. Etc.

With ATSC 1, there was a bunch of extra spectrum available for transition, and federal mandates, and subsidized converters. There's none of that for ATSC 3, so it's going to be slow.

[1] https://www.rabbitears.info/market.php?request=atsc3

Just to be pedantic, 1080p24 (and 1080p30, and the 1000/1001-rate versions) are already allowed by the existing A/53 spec and have been since 1995. The big (1080-line) broadcasters usually transmit their film-style programming as "effectively" 1080p24, in the sense that they're sending 24 or 24000/1001 progressive-scan coded pictures per second, but with flags that ask the decoder to perform a 3:2 pulldown to output 60 fields per second so it fits seamlessly within a 1080i30 sequence. (They could be sending "true" 1080p24, but then it would probably create a glitch when they transition to 60 fps content and back.)

But anyway: 1080p itself is not a new feature of ATSC 3.0. 1080p60 or 1080p120, sure.

A bit of a nitpick: 1080p24 was added in 2008 along with h.264. It was not part of the original spec, so the original HDTV sets could not decode it. Broadcasters sensibly don't send 1080p24 since 1080p60 is "good enough" and works on all TVs.

If you're nitpicking, I think you mean 1080i60 is good enough.

Not so -- 1080p24 and 1080p30 sequences (and the 1000/1001-rate versions) were part of the original A/53 specification in 1995. This is for H.262 video (MPEG-2 part 2). It's also in the 2007 revision (see A/53:2007 part 4, table 6.1.2 [1]). In practice, what broadcasters really do is send a sequence labeled 1080i30 for everything, but during the 24P content, they send 24 progressive-scan frame pictures per second, with picture flags that instruct the decoder how to perform the 3:2 pulldown to manufacture 60 fields per second at the receiver. This kind of "1080p24" is very common and they've been doing it since the 90s or early 2000s. The same basic technique is used on NTSC DVDs.

([1] https://prdatsc.wpenginepowered.com/wp-content/uploads/2021/.... Pedantic note: What the FCC adopted is slightly more generous than the ATSC spec; they excluded this table, both pre- and post-2007. So technically speaking, anything "Main Profile @ High Level" is allowed on the U.S. airwaves, but it doesn't matter in practice.)

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