PSA: Do not hold your breath waiting for (free) ATSC 3.0 broadcasts in 4K.
I honestly don't care about 4K. I just asked because I was interested but I meant more of the video quality itself when recording a show. Would the video file be better as a HVEC recording
I'm far from an expert on this stuff, but here's what I'm seeing from personal experience and what I've learned from reading other threads. No, the channels are not 4K, but I didn't expect them to be. I knew that such content is rare, and most likely will be paywalled when it's available..
However the ATSC 3.0 channels with HEVC have other benefits. Apparently the ATSC 3.0 signal is less prone to interference in metro areas. I'm seeing that with the 3 channels I'm now able to tune into, the signal sees stabler, without the occasional glitches I'd see on ATSC 1.0, and the PQ is noticeably better.
For specific numbers:
KTLA and KTTV on ATSC 1.0 were broadcasting at 1280 x 720
And now on ATSC 3.0 they are both broadcasting at 1920 x 1080p
So that's feels like the jump from DVD to Blu-Ray quality.
And it also now supports 10-bit color.
No, it's not "UHD" (4K) but it's still a very noticeable jump in visual quality.
I note that KCOP is still 720p. But it's definitely a stabler signal, compared side by-side with ATSC 1.0. I don't really watch any content on that channel, it's mostly older stuff... probably being upscaled from VHS tape quality...
Here's specs I found in this very detailed thread: discussing Los Angeles ATSC 3.0:
Video
ID : 49 (0x31)
Menu ID : 3 (0x3)
Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main [email protected]@Main
Codec ID : 36
Duration : 22 h 31 min
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 59.940 (60000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 10 bits
Color range : Limited
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709
Also ATSC 3.0 and its HEVC compression for video is about 3-4 times more "efficient" for carrying video data as ATSC 1.0 and its MPEG-2 compression. I'm assuming this means the recordings made in Channels DVR will be smaller.
I'm also now able to pull up a strong KCAL (9.1) signal whereas previously I had a difficult time with that channel specifically. I don't know if that's a result of the HDHR firmware update, some repositioning of the antenna, more bandwidth available or less interference now that wireless signal assignments have changed, or some combination of all of that and maybe more... but, my local channel availability and overall PQ has never been better with Channels DVR and now I'm even happier with it.
I don’t know about the LA market but in my market the picture quality of atsc3.0 hevc is noticeably better that atsc1.0.
Thank you for the information. I also live in the LA market so I'm probably going to pick one up then. I watch a lot of channel 11 and channel 5 and 13 so I will really benefit from it
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720p is not dvd, it’s Hd
DVD is 480p or Enhanced definition TV (EDTV)
VCR is not 480p, it’s 480i and below.
OK so what is 1080p?
HD or if you like to spend money on marketing, it’s Full HD
OK well on the same content I can definitely see the difference between 720p HD and 1080p Full HD, that's for sure.
Yea you should, it’s more lines and information.
Maybe the 10-bit color is helping. And the overall signal seems more stable, too. At least in my location with this indoor antenna I'm currently using: https://amzn.to/34jaLIX
My hot-takes on ATSC3...
- The AC4 audio requirement will be a significant pain point. Too bad the individual broadcasters can't decide whether to use AC4, EAC3 or AC3.
- We're going to be suffering through some awfully ugly ATSC1 broadcasts as the transition progresses and more streams are packed into each ATSC1 channel. There is a 10-year or so period where the primary (x.1) channels must remain available via ATSC1.
- The major broadcasters may never fully buy-in. They will much prefer you pay for high quality streams.
The last four paragraphs of this article are interesting.
Thanks for the info! Didn't get a Flex since I didn't think there would be any PQ improvements until the full ATSC 3.0 rollout.
I got the flex 4k set up and did some test recordings on it with the hvec channels on the channels app they play fine it seems however on the computer using VLC i have no audio and the picture is split into two and the color is purple? has anyone else had this happen?
I just tested with a quick recording from 111.1 KTTV.
It looks and plays fine in Channels DVR, on the webUI as well as Channels app. Of course 
I then opened the same recording on my Mac, using VLC and also IINA. The picture is fine on both, but the audio track isn’t recognized. I typically don't use 3rd party external players with Channels content, so I'm not really sure why there's any difference here. But I do wonder if this discussion has something to do with the issue being discussed: ATSC 3.0 Los Angeles Audio Issue (no audio) on Fox 111.1 - Silicondust
interlaced hevc and lack of AC-4 audio support most likely.
Here's a video player that supports AC-4 decoding, by way of an "experimental version" of FFmpeg, so video and audio play back from these ATSC3 recordings:
It's for Windows, but worked fine for me on my Mac running Parallels. The test recordings I made now include audio on playback.
The FFmpeg project itself has been taking their time to integrate support: #8349 (Dolby AC-4 Support) – FFmpeg
Once it's officially in FFmpeg, then apps like VLC, IINA, Handbrake, Permute and the like should be able to play/convert them too.
Maybe I've missed it, but is there a way to tune the ATSC 3.0 channels (111.1) when going to the standard HD channel 11.1? Mainly trying to get the channels to show up in the guide where the original channel is vs scrolling into the 100's. But also would be helpful to make all recordings use that channel by default as well.
I don't know the answer to that specfically but I'm using customized Channel Collections for all of my browsing and channel surfing, including Favorites (and love that they automatically sync to all my TVs.). With this method it's easy to organize the channels wherever I want them in the guide, in any order I choose. So I just replaced channel 11.1 with the 111.1 one in the Guide. I basically ignore the displayed numbers after that, all of the channel collections are manually sorted in ways that makes better sense to me. In fact I'd love to be able to turn off channel numbers completely.
For forcing recordings to only use a specific channel, you can add that rule, in Advanced Pass editing on the Channels DVR webUI.
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From what I have seen of ATSC3 broadcasts in LA, the quality is the same as before. The bit rate is halved, which benefits the broadcasters (but not really us!) And it looks like some content that used to be 720p is now 1080p. HOWEVER
ATSC3 doesn't just give us a better codec, it also uses a different modulation scheme that's supposedly more robust against the most common causes of poor signals (basically reflections from large buildings interfering with the primary signal). This does seem to work well, in the sense that the quality of signal I get now seems substantially better than before. I don't think I've seen a single dropout on ATSC3 whereas on the same channel (FOX) before this was common.
Of course the channel frequency being used by the ATSC3 signal is also different, so don't take that as gospel...
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