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The ATSC 3.0 stations are not sending out 4K, it's just 1080p, 1080i or 720p simulcasts on shared "lighthouse" stations, leaving no room for 4K.

There won't be enough bandwidth for 4K OTA from the networks until after the 5 year ATSC 1.0 simulcast period is over, and 3.0 tuner penetration is high enough that those shared stations can drop ATSC 1.0 entirely and switch to standalone ATSC 3.0 signals without losing a significant portion of their OTA viewing audience. And since as of now only large size TVs come with ATSC 3.0 tuners and there's no plans to distribute coupons for free converters or a mandate that all TVs come with NextGen tuners, it's going to be a while before that happens.
Ahhh, thanks for bursting my bubble - (kidding). This is the info I have been looking for. Seeing all the news about 3.0 in PDX led me down this path. Guess I'll have to be satified with streaming options to get my UHD fix.
 

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NextGen, or ATSC3 if you will, does not seem to be prospering. There is a great deal of effort/commotion among the broadcasters but almost none among the TV set vendors. I did my periodic Google search for ATSC3 capable TV sets yesterday and found few, if any. For instance, I searched the BestBuy site for NextGen or ATSC3, etc, and came up with absolutely nothing. One would think that they would be starting to push ATSC3 sets as they don't get the chance to replace existing technology too often. The results of this fall's search was nearly the same as last fall's. All of Samsung's and Sony's ATSC3 info is dated in May and June and they only have a very few high-end sets for ATSC3. Christmas is upon us and neither is pushing the ATSC3 option.

One gets the sense that the ATSC3 standard is so flexible (read complicated) that it's very difficult to engineer products for. I am vaguely familiar with the ATSC3 physical layer standard and the number of options the receiver designer must cope with is staggering. But, this is only one of twenty-two ATSC3 standards.

Just as a comment, KOXO RFch.15 returned to the air with its ATSC3 signal a week or two ago. However, it's at a much reduced power.

L
 

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I've been fiddling with my new Sony Bravia XBR 65- 90CH which, as I understand it, can tune in NextGen ATSC 3.0 broadcasts.
NEXTGEN TV has not yet been enabled on the 90CH and 900H.

You're not missing anything as I've pointed out previously and KyL416 reiterates.

That the channels look better owes to the Sony being a better TV than you had before as the signals perhaps aren't as good with the addition of more subchannels to all but KOPB.
 

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The consumer electronics industry has just gotten around to defining what an ATSC3 receiver must do.
The broadcasters and their vendors certainly shouldn't be held harmless in this apparent foot-dragging. They're the ones determining what is going to be delivered from a signal perspective.
 

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After almost two months of transmitting an ATSC1 carrier with no modulation, KPXG-LD RF21, Vir42 has finally added modulation to its signal. I see two virtual channels, 42-1 and 42-2. Both are religiously oriented.

Linley
 

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Is getting an ATSC 3.0 capable device like the HD Homerun the only way to get picture quality back on the main OTA channels like it was before? If I am reading the last few pages correctly will we be living with worse picture quality for 5 years on ATSC 1.0? Football on CBS and especially NBC used to be fantastic and now not so much.
 

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Is getting an ATSC 3.0 capable device like the HD Homerun the only way to get picture quality back on the main OTA channels like it was before? If I am reading the last few pages correctly will we be living with worse picture quality for 5 years on ATSC 1.0? Football on CBS and especially NBC used to be fantastic and now not so much.
If P.Q. is the most important thing, your best bet is Comcast or YouTube TV as they encode at the NOC prior to the ATSC 1.0 (or NextGen TV, ATSC 3.0) encoding is performed. For OTA, ATSC 1.0 will still be the best P.Q. until the NextGen TV encoding is enhanced via the OTT broadcast app (no ETA for Portland).
 

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If P.Q. is the most important thing, your best bet is Comcast or YouTube TV as they encode at the NOC prior to the ATSC 1.0 (or NextGen TV, ATSC 3.0) encoding is performed. For OTA, ATSC 1.0 will still be the best P.Q. until the NextGen TV encoding is enhanced via the OTT broadcast app (no ETA for Portland).
I have YouTube TV and have compared it to OTA and they look similar. Good to know they are encoding like that and also they output 720p as 720p and 1080i as 1080p. I still remember the locals from whatever source previously looking better than they do now on YouTube TV or OTA.

I used to have Comcast and it looked great for NBC and OPB as they kept those at 1080i but that also was before the Next gen changes/additional channels impact. Don't know what it looks like now. Also Comcast converted CBS's 1080i to 720P and that wasn't good.
 

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HEVC DOES support interlaced video and there are numerous ATSC 3.0 stations doing 1080i, the problem is FFmpeg's implementation of HEVC doesn't currently support it so things based on it like VLC, Kodi, Plex, Emby and others decode 1080i as 1920x540p.

Now if you're watching on a NextGen compliant TV, it will support interlaced HEVC since it's part of the ATSC 3.0 specs. (Search for "interlaced" in the PDF, or scroll down to section 6.2.2)
 

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HEVC DOES support interlaced video and there are numerous ATSC 3.0 stations doing 1080i, the problem is FFmpeg's implementation of HEVC doesn't currently support it so things based on it like VLC, Kodi, Plex, Emby and others decode 1080i as 1920x540p.

Now if you're watching on a NextGen compliant TV, it will support interlaced HEVC since it's part of the ATSC 3.0 specs. (Search for "interlaced" in the PDF, or scroll down to section 6.2.2)
The bitstream is 1080p, however metadata can be added to allow a decoder to interpret it as interlaced video. (High Efficiency Video Coding - Wikipedia)
 

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If P.Q. is the most important thing, your best bet is Comcast or YouTube TV as they encode at the NOC prior to the ATSC 1.0 (or NextGen TV, ATSC 3.0) encoding is performed.
I would argue that this erroneously assumes that these services don't engage in significant conditioning (i.e. summarily converting everything to 720p) of the streams.
For OTA, ATSC 1.0 will still be the best P.Q. until the NextGen TV encoding is enhanced via the OTT broadcast app (no ETA for Portland).
OTT obviously isn't OTA.

If the plan is to move the high quality modes to OTT, that substantially defeats the purpose of OTA from the viewer's perspective -- good quality at no monthly cost. I think that's likely to do some serious damage to public adoption of a technology whose future would appear to be largely bound to public adoption (even if the DTV signals go away).
 

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HEVC DOES support interlaced video and there are numerous ATSC 3.0 stations doing 1080i, the problem is FFmpeg's implementation of HEVC doesn't currently support it so things based on it like VLC, Kodi, Plex, Emby and others decode 1080i as 1920x540p.
It wasn't in the HEVC spec when I looked at it about four years ago but I guess they had to fix that for the broadcast industry. I hope they included all the excellent interlace modes that are in AVC.

This isn't a fake interlace mode like they had in MPEG1, is it? You had to send each field as a half-height progressive image.
 

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In the end, it's detected as interlaced video on nextgen compliant TVs. In many cases the ATSC 3.0 versions of the stations are broadcasting 1080i HEVC since that's the resolution NBC, CBS, CW and PBS are sending out on their master feeds.

The problem is much of FFmpeg's developers are based in countries that use the DVB standard for digital television instead of ATSC, so things like AC-4 and interlaced HEVC aren't an issue that personally affects them, and since it's open source many of them are maintaining the code in their spare time and have regular day jobs. ATSC 3.0 stations are in lighthouse mode only carrying primary channels, so SD only subchannels aren't an issue yet, but many of them originate as 480i feeds, which will appear as 240p channels if the bug isn't addressed by the time the 5 year simulcast period is over. If people want, they can contribute to the bounty source for those bugs to give them more of an incentive to do it:
Interlaced HEVC supprot
AC-4 Support
 

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In the end, it's detected as interlaced video on nextgen compliant TVs. In many cases the ATSC 3.0 versions of the stations are broadcasting 1080i HEVC since that's what NBC, CBS, CW and PBS are sending out on their master feeds.
Yes, just as MPEG1 was displayed as interlace. Of course it was easy back then because there wasn't anything else.

The problem FFmpeg developers are having right now is that there are no ATSC 3.0 receivers so there's no demand to support ATSC 3.0 at this point. There are millions of people who use products based on FFmpeg in the U.S. so I'm sure this will change. I was using xine and mplayer to display ATSC 1.0 long before there was HDTV in Europe. It's driving me nuts that I can't receive our two ATSC 3.0 stations. :)
 
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