ATSC3.0 Broadcast and AC-4 Sound

I have the same problem. I enable the channels and try to save the configuration and it does not save. I would like to be able to record the ATSC3 channels and decode the audio offline.

I thought there was no difference for my first few minutes of playing around with it. This is absolutely incorrect though. If you watch a local news broadcast, for example, look for white banners with black text. With the MPEG2VIDEO compression you see noise around the text. There is a actually an objective difference in picture quality at the same bitrate and resolution, as one would expect.

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I suspect they won’t and neither will Emby. Plex’s purpose is to record, remove commercials, and rebroadcast. Those are literally the things that DRM is implemented to prevent.

If the broadcaster can do a better job of interlacing and upscaling than your TV then yes you could see a difference. It is the same content upscaled. I have looked pretty hard and see no difference as my TV does a very good job


What I’m receiving on the channel that I referenced is 720p60 for both feeds. All the ATSC3 feeds are the same resolution as their ATSC1 counterparts here. Do you really think it’s more likely that I see noise around edges because of upscaling to 720p, rather than a 30 year old compression codec? We are talking 720p at 6mbps, max, and the argument is that at 6mbps, HEVC is no better? Seems to be the stations are getting their feed at 720p, I understand, but that doesn’t mean that it isn’t a higher bitrate than what gets transmitted OTA.
I think that mpeg2video would look just as good at 12mbps, but I’m not seeing that anywhere.
I think people were trying to temper expectation that ATSC3 would bring 4k OTA. Somehow that got taken into “It’s no better” territory. It’s less bad at 720p 6mbps.

You are getting 720P60 on ATSC 3.0 channels? That is pretty strange as it should be 1080P. What tuner are you using? What about the 1080i stations (NBC CBS)?

I think just about all of us messing with ATSC3 are on the Flex 4k. What makes you think it should be 1080p? I’m always trying to learn.
I do have a correction. This area’s Fox affiliate’s 720p ATSC1 feed is 8Mbps average and the ATSC3 feed is 6Mbps average. The HEVC compression looks better at a lower bitrate even in 720p. You can pause it and pick out the differences if you know where to look. It’s an upgrade similar to going from cable (Spectrum) to ATSC1 is here. When someone with cable sees 720p ATSC1 on an old budget Vizio and says “Wow, the picture is nice on this TV.” sigh

My local NBC affiliate is broadcasting their ATSC1 feed at 1080i res. The ATSC3 feed is also 1080 but I can’t remember if it was 1080i or 1080p, now I can’t check because they locked it with DRM. I can pull an NBC ATSC1 feed from another market but I can’t compare that to the ATSC3 feed from that market because their lighthouse station is out of my reach. There’s a third market where the Flex 4k is listing the HEVC stations but I don’t think I can tune them. I may try.

Interesting. ATSC 3.0 is supposed to be 1080P for all channels in the current lighthouse implementation. I have never seen anyone get anything different before. Seems something unique is being done in your market. I dont have that level of knowledge to have any idea what
 If you are interested enough, there are industry people in this thread that actually run these systems that could shed some light on it. Atsc 3.0 | AVS Forum

BTW, I also have a Flex4K and a Sony TV with native ATSC 3.0 tuner. Like you I also have a plex Pass and it is my DVR. There is always the HDHR DVR license which is pretty inexpensive.as an option if you get tired of waiting. They finally have a grid guide vs the “different” slice guide.

My local Fox and ABC affiliates are still 720p60 (HEVC) on ATSC 3.0 as well. I don’t believe I’m in the same market, because my NBC affiliate is running 1080p60. This is with an HDHomeRun, so I can download the transport stream to confirm the native resolution. Though I usually just stream it through VLC and check the codec info.

This is interesting.
If I use the Sony TV with built in ATSC 3.0 tuner and hit the display button on the remote, ATSC 1.0 channels show 1080i or 720P AC3 as appropriate. All ATSC 3.0 channels show 1080P AC4

The HDHR works a bit differently. The display button doesnt do quite the same thing with the HDHR app. ATSC 1.0 channels show either “HD” (which means720P) or “Full HD” (which means 1080i or p). All ATSC 3.0 channels show “Full HD” meaning not coming through as 720P

VLC does indeed show 720P or 1080i. Not sure what VLC is doing. Maybe reading the original meta data or maybe it reads through the upscale to see the actual original resolution? I dont know VLC well enough to say.

BTW can you guys get Plex to work at all with the HDHR? When I try to add an ATSC 3 channel, I have to map it to a guide channel. The 1xxx guide channels dont show. I can just map to something else but I can never actually tune a channel. It just fails playback.

You can view the broadcast resolution and other technical data for your market at RabbitEars.Info

I would bet FOX and ABC are still sending 720p60 to all the local stations. They chose that resolution early on because 60 fps was better for sports and ATSC 1.0 couldn’t do 1080p60.

I doubt the local stations are setup to down res the video so they are probably still sending 720p60 and the local stations are probably just taking a single feed and sending it out over ATSC 1.0 and ATSC 3.0.

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Emby remote from home.

What I was saying before we drifted is that since Hearst is turning on DRM, the fun is ending. I’ve enjoyed ATSC3 on Emby for months but in defense of Plex, it may be a total waste of time. If Sinclair and the others follow Citizen Kane III’s lead, we will be limited to the HDHR app. No DVR, no comskip, no Plex, no Emby etc.

I was just reading about the Hearst DRM thing yesterday. Its like they are trying as hard as possible to keep people from adopting ATSC 3.0. OTA is dying and this certainly does not look like its savior.

For me, main use case is NFL. Timeshift record to skip the commercials and 1/2 time. About to go watch the Bills/Miami game. Other use case is wife likes Jeopardy (so do I) and we watch minus the commercials. Other occasional stuff. Not exactly a big use case.

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Yep. In my case the Flex 4k allows me to put up one antenna and serve my family through Emby. None of us are out of market and I’d say 95% of watch time is live, so their commercials are being watched. I can’t imagine anything about my use case would be undesirable to Hearst but they are throwing out the baby with the bathwater.
I really think they deserve historical notoriety for this move.
“What would you like to have been?”
“Everything you hate.”

That’s exactly my assumption as well.

I remember the debates about that, a long time ago!

It’s funny though, because once deinterlaced at the client (bob) to 1080 at 59.94fps, sports on NBC/CBS look outstanding and have no motion issues. Heck, Comcast now just pre-emptively encodes all locals to 720p60 and you’d be hard-pressed to tell which were originally 1080i and which were 720p.

If anyone is still interested, more info on the actual resolution of a broadcast with ATSC 3.0. The answer seems to be it depends on what your local market is doing. The TV can report signal as 1080P but that doesnt tell you what the actual resolution is, If you are using HDHR, the VLC tools will tell you. If not you can use Rabbit Ears

Here is my local market:

Here is New Orleans

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Did Plex just stop supporting ATSC 3.0 entirely? I used to get the channels without sound, but now they won’t tune in at all (on Plex, fine using HDHR app).

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Depending on your market and the broadcasters themselves, you might be experiencing DRM on those channels, which I’m not certain if Plex is ready to decrypt them yet, Have you tried using the HDHomeRun app to double check what channels are affected?