ATSC 3.0 Issues

[DSperber]

Isn't "Spa" what you'd expect for "Spanish"?

[nickk]

"spa" is the language code for Spanish.

Shows will often have a second audio track. The most common types are 1) Spanish language and 2) Descriptive Audio.

Sometimes a broadcaster will flag the second audio track as both Spanish AND Descriptive Audio even though it is only one or the other. This is the fault of the broadcaster.

[kyl416]

Not really for ATSC 3.0, but most of it is backwards compatibility for older tuners from before DVS was mandated and only has a language based selection option in the menus, so the ISO 639 language descriptors are what gets passed along to the ATSC 3.0 airchain. Like locally my PBS station uses "spa" for the DVS feed on all of their channels, while their Create subchannel also has "fre" and "deu" tracks that carry the audio of their 2 NPR stations.

They also have "visually impaired" specified as the mode on their "spa" labeled tracks, and some newer tuners that parse that data will display those tracks as DVS instead of Spanish.

[danieljlevine]

Isn't "Spa" what you'd expect for "Spanish"?

LOL! Oh makes perfect sense then. Oddly they didn’t have Spanish audio playing in it. I stand properly corrected.

What about the Dolby Atmos audio. Is there a suitable option the broadcaster is supposed to set for that and they aren’t? Or is there not even an option. I suppose the 5.1 could become 5.1.4 or could say Atmos in the standard when set.

[danieljlevine]

Found this document:

https://www.atsc.org/wp-content/uploads ... ements.pdf

Looks like 5.1.2 or 7.1.4 and HOA(#) are potential options.

So I guess FOX WBFF is labeling the channel as 5.1.

Assuming I git the 5.1.2 right, maybe HOA(10). Wish I had tried this out during the Superbowl when they intended to broadcast Atmos. Perhaps it would have said something different.

Maybe 5.1 is correct now, since the audio program is likely 5.1.

[danieljlevine]

Thanks!

Media Info is really good!

For my Fox WBFF 145.1 ATSC 3.0 channel:

Audio is reported as Dolby Atmos 5.1.2
Video is 720p SL-HDR1, v1.0

Channels had a big update which finally lets me see how many audio channels are in their stats. It reports 12 for this channel. Not sure how to make that agree with the media info output. This would be 7.1.4. Switching the SAP to Spanish reports 2 audio channels. So that seems right.

[danieljlevine]

During the Superbowl, I noticed and reported an issue here where the ATSC 3.0 audio was consistently falling behind the video. Pausing and resuming did’t fix it. Pausing, rewinding, forwarding and playing did. But it would eventually fall behind. I was watching on my new Firestick 4K (2nd Edition) and wasn’t sure if it was the HDHomerun 4K, Firestick 4k, broadcast in Dolby Atmos, etc. Nothing seemed to come of that report.

Well today I was watching the Oscars on ABC over ATSC 3.0 on the same hardware and noticed the same thing happening. So no Dolby Atmos to blame. But this time I also watched on my iPhone simultaneously. The iPhone did not have the issue using the HDHomerun app. So it would seem that there’s an audio issue with ATSC 3.0 audio falling behind the video on Firestick 4K 2nd generation.

[lenlab]

I reported on this forum that there were lip sync issues with my 3 non DRM ATSC 3.0 stations in the NYC area. Not sure if it is really a Flex 4K issue, a fireTV stick issue, an SD software issue etc.. It is so bad I can't watch shows with any people talking and only stick to nature and shows with less talk.

[danieljlevine]

Do you know if you have a Gen 1 or Gen 2 Firestick 4K? I don’t recall having the issue with a Firestick 4K Gen 1 device. I can actually test that theory myself and see on another TV that still has a Gen1 Firestick 4K.

[lenlab]

I have the latest (new) gen 2 4k fireTV stick. I checked on other forums and other tuners seem to have lip sync issues too with ATSC 3.0. So it is not an isolated issue. Someone even said the station was contacted and the engineers did something to fix it. Oi vey!

[danieljlevine]

So, I can see how that could be the case in some instances. But if it looks fine on a different player and platform with the same tuner and stations, then something else is going in locally after the HDHR Flex 4k device.

I did my test on the Firestick 4K Gen 1 setup and I didn't notice the issue where the lip sync got further and further behind on ATSC 3.0 stations. It seemed like there was something slightly off with the lip sync, but my other setup doesn’t use eARC and would get the SD AC-3 playback conversion, so there might be something slightly off. I didn’t notice any lip sync issues with ATSC 1.0 in this setup. And I didn’t notice a lip sync drift getting worse and worse over time like I did on the Gen 2 Firestick 4K. On iPhone I didn’t notice the issue at all either.

Perhaps the next test is to use another way of viewing the channel on the TV like the DNLA media viewer and see what I see. I think I’d get no audio on the Firestick 4K Gen 1, since it doesn’t support AC-4 audio. Oh, but that would be the same for both cases for me, since neither of my Samsung TVs or audio equipment handle AC-4 in their own. So maybe I need such a media player on the Firestick 4K Gen 2 TV stick for the test.

[danieljlevine]

Ah, I think I just need to do this with the Silk browser: viewtopic.php?t=74254

[danieljlevine]

Tonight's testing on the Firestick 4K Gen 2 didn’t suffer lip sync delays. So I didn’t need to do the web browser test. I wonder if the issue is dynamic or environmentally influenced somehow.

[howardc1243]

Tonight's testing on the Firestick 4K Gen 2 didn’t suffer lip sync delays. So I didn’t need to do the web browser test. I wonder if the issue is dynamic or environmentally influenced somehow.

it can also be a poorly defined plp structure.