AC-4 Audio - talkenrain

ATSC 3.0 Forum
talkenrain
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AC-4 Audio - talkenrain

Post by talkenrain »

RECENT UPDATES OBSERVATIONS:
NVEDIA SHIELD PRO running HDHOMERUN Release 20210104 - Portland market, Atmos system - Random crashing on channels 8.1 (NBC) and 12.1 (FOX), Audio now maps correctly on channels 8.1 (NBC), 10.1 (PBS), 12.1 (FOX) and 49.1 (MyTV). Audio favors left front speaker on channels 2.1 (ABC), 6.1 (CBS), 32.1 (CW).

AppleTV running HDHOMERUN release 20210102 - Portland market, atmos system - Audio is still not right but better (stable to the point the av pressor is no longer switching between formats). still favors left front or left surround on all ATSC 3.0 channels

LGTV running HDHOMERUN release 20200923 - Portland market, atmos system - This is the golden standard. Works great, sounds great. consistent on every channel.

CBme
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Re: AC-4 Audio?

Post by CBme »

talkenrain wrote: Wed Jan 06, 2021 7:40 pm RECENT UPDATES OBSERVATIONS:
NVEDIA SHIELD PRO running HDHOMERUN Release 20210104 - Portland market, Atmos system - Random crashing on channels 8.1 (NBC) and 12.1 (FOX), Audio now maps correctly on channels 8.1 (NBC), 10.1 (PBS), 12.1 (FOX) and 49.1 (MyTV). Audio favors left front speaker on channels 2.1 (ABC), 6.1 (CBS), 32.1 (CW).

AppleTV running HDHOMERUN release 20210102 - Portland market, atmos system - Audio is still not right but better (stable to the point the av pressor is no longer switching between formats). still favors left front or left surround on all ATSC 3.0 channels

LGTV running HDHOMERUN release 20200923 - Portland market, atmos system - This is the golden standard. Works great, sounds great. consistent on every channel.
Interesting. In Seattle the CH carrying NBC and FOX plays correctly with the latest update (but defaults to SAP) but our CH carrying ABC and CBS (no CW yet) is the one that has everything in the front left. Does that on 2019 Sheild (I don't have crashes in my testing anymore), XBox One, PC and Samsung phone. I wonder if the markets are using the same two audio schemes for the two groups of channels.

tmm1
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Re: AC-4 Audio?

Post by tmm1 »

talkenrain wrote: Wed Jan 06, 2021 7:40 pm Audio favors left front speaker on channels 2.1 (ABC), 6.1 (CBS), 32.1 (CW).
Can you share samples from these stations?

talkenrain
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Re: AC-4 Audio?

Post by talkenrain »

CBme wrote: Wed Jan 06, 2021 9:57 pm
talkenrain wrote: Wed Jan 06, 2021 7:40 pm RECENT UPDATES OBSERVATIONS:
NVEDIA SHIELD PRO running HDHOMERUN Release 20210104 - Portland market, Atmos system - Random crashing on channels 8.1 (NBC) and 12.1 (FOX), Audio now maps correctly on channels 8.1 (NBC), 10.1 (PBS), 12.1 (FOX) and 49.1 (MyTV). Audio favors left front speaker on channels 2.1 (ABC), 6.1 (CBS), 32.1 (CW).

AppleTV running HDHOMERUN release 20210102 - Portland market, atmos system - Audio is still not right but better (stable to the point the av pressor is no longer switching between formats). still favors left front or left surround on all ATSC 3.0 channels

LGTV running HDHOMERUN release 20200923 - Portland market, atmos system - This is the golden standard. Works great, sounds great. consistent on every channel.
Interesting. In Seattle the CH carrying NBC and FOX plays correctly with the latest update (but defaults to SAP) but our CH carrying ABC and CBS (no CW yet) is the one that has everything in the front left. Does that on 2019 Sheild (I don't have crashes in my testing anymore), XBox One, PC and Samsung phone. I wonder if the markets are using the same two audio schemes for the two groups of channels.
Good question. I’ve heard the crashing with the NVIDIA shield pro is more about bad reception but I’m only 3 to 4 miles from the towers and on a mountain top. I can see all the towers from my street. With an outdoor rooftop antenna there is zero chance of a weak signal. If anything, maybe too much signal or multi-paths I would think would be more of an issue than signal strength. Whenever I check with the browser tool the signal is always 100 and the quality bounces between 70 something to 100.

Re Audio:, I have not noticed if it’s SAP on some of the channels. I’ll check next time it’s on. I’ve spoken (emailed) the local head engineers at our NBC and ABC stations early on, when I was considering this ATSC 3.0 tuner . Very friendly people. Maybe I should open dialogue with them again to get more on-site on broadcast differences. I assumed they where the same but there must be a reason we’re getting different results from different stations...

I also hear an ffmpeg ac4 decoder is working. Great news for PLEX users. I hope it works it’s way into a not to distant release. I’d like to be ready by the time the networks have there first 4k feed to local broadcasters. Can’t wait...

signcarver
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Re: AC-4 Audio?

Post by signcarver »

With quality bouncing like that you have bad reception and at that distance an outdoor antenna is probably overkill and would make your signal too hot. My personal recommendation is to never have signal strength at 100% as you won't no how much above 100% it is (though a 4k dev unit can help with that as it can give actual dBm)

talkenrain
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Re: AC-4 Audio?

Post by talkenrain »

signcarver wrote: Thu Jan 07, 2021 7:39 am With quality bouncing like that you have bad reception and at that distance an outdoor antenna is probably overkill and would make your signal too hot. My personal recommendation is to never have signal strength at 100% as you won't no how much above 100% it is (though a 4k dev unit can help with that as it can give actual dBm)
Agreed but not a valid reason for the app to crash on one platform while preforming well on others using the same signal conditions and tuner. I think the signal quality fluctuation is a result of mulipaths so i'm not confident attenuating the signal alone will make things better without some form of multipath rejection. I was thinking when the weather is better I'd get a more directional antenna (currently a very wide view unit) and attenuate the signal at the tuner try to eliminate the excessive bounce and improve the signal to noise ratio.

The HDHOMERUN app crashing on the Nvidia shield pro is better than it was but still happens about once every 30 minutes. does not pass the wife standard. HDHOMERUN app never crashes using the AppleTV 4k, or when using the LGTV os.

talkenrain
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Re: AC-4 Audio?

Post by talkenrain »

tmm1 wrote: Thu Jan 07, 2021 12:08 am
talkenrain wrote: Wed Jan 06, 2021 7:40 pm Audio favors left front speaker on channels 2.1 (ABC), 6.1 (CBS), 32.1 (CW).
Can you share samples from these stations?
Happy to share, tell me how to capture and I'll send it...

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Re: AC-4 Audio?

Post by tmm1 »


talkenrain
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Re: AC-4 Audio?

Post by talkenrain »

signcarver wrote: Thu Jan 07, 2021 7:39 am With quality bouncing like that you have bad reception and at that distance an outdoor antenna is probably overkill and would make your signal too hot. My personal recommendation is to never have signal strength at 100% as you won't no how much above 100% it is (though a 4k dev unit can help with that as it can give actual dBm)
After re-reading your reply I thought I should take a closer look. I don't have the dev kit so the best I could do is monitor with the browser. Here is the result of about 2 to 3 minutes of monitoring each ATSC 3.0 channel:

Channel 2.1 Signal strength 89% to 90%, Signal quality always 100%, Symbol quality always 100%
Channel 6.1 Signal strength always 89%, Signal quality always 100%, Symbol quality always 100%
Channel 8.1 Signal strength always 100%, Signal quality 100% (rarely 96%), Symbol quality always 100%
Channel 10.1 Signal strength always 100%, Signal quality 100% (rarely 96%), Symbol quality always 100%
Channel 12.1 Signal strength always 100%, Signal quality 100% (occasionally 98%), Symbol quality always 100%
Channel 32.1 Signal strength always 89%, Signal quality 100% (occasionally 98%), Symbol quality always 100%
Channel 49.1 Signal strength always 100%, Signal quality 100% (rarely 98%), Symbol quality always 100%

These numbers don't look near as bad as I'd thought but maybe I'm reading them wrong? On occasion channels don't tune in and I have to tune away to a different channel then come back to get it to lock. What would cause this behavior and how would you suggest I improve reception (if needed). I'm really trying to get past this Nvidea Shield Pro crashing but if I can improve my signal at the same time I'm interested in learning how.

talkenrain
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Re: AC-4 Audio?

Post by talkenrain »

Got it. Thanks here you go. 4 files:
Portland market.
http://www.wnsunwired.com/hdhomerun/
ABC 2.1 - 102.mpeg - audio favors left channel
CBS 6.1 - 106.mpeg - audio favors left channel
NBC 8.1 - 108.mpeg
PBS 10.1- 110.mpeg

petemitchell
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Re: AC-4 Audio - talkenrain

Post by petemitchell »

I'm confused. If my receiver can decode ATMOS, does that mean it can also decode AC-4? If not, how does the Shield TV handle it?

Dartman
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Re: AC-4 Audio - talkenrain

Post by Dartman »

My 2018? Shield now has ok audio and video on the 3.0 channels in Portland. The Roku Ultra latest release I recently got still doesn't and neither does the Roku built-in to my TCL 65 825 TV. So something by somebody got a update that makes the earlier Shields work recently.
So finally one of my media players works :D
Last I checked a day or two ago it did not work but I think every one that cares is working to add support for ac4 audio and other new codecs coming online with 4k TVs and movies so hopefully more platforms that are popular enough with get it soon. I haven't poked around here much today to see if Silicon Dust added it or Google did it but definitely happy because now I have a way to watch 4k OTA TV with my new tuner if Portland finally actually does 4k soon rather than testing it with regular HD content right now.

talkenrain
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Re: AC-4 Audio - talkenrain

Post by talkenrain »

Dartman wrote: Fri Jan 08, 2021 9:45 pm My 2018? Shield now has ok audio and video on the 3.0 channels in Portland. The Roku Ultra latest release I recently got still doesn't and neither does the Roku built-in to my TCL 65 825 TV. So something by somebody got a update that makes the earlier Shields work recently.
So finally one of my media players works :D
Last I checked a day or two ago it did not work but I think every one that cares is working to add support for ac4 audio and other new codecs coming online with 4k TVs and movies so hopefully more platforms that are popular enough with get it soon. I haven't poked around here much today to see if Silicon Dust added it or Google did it but definitely happy because now I have a way to watch 4k OTA TV with my new tuner if Portland finally actually does 4k soon rather than testing it with regular HD content right now.
Is your Nvedia shield connected to an Atmos sound system? Do you know for sure your shield is mapping the audio channels correctly? My Nvedia shield pro (2020) crashes on channels 8.1 an 12.1 usually within 1 minute. Other channels work fine. Nvidia Shield Pro does not crash when using the Channels app instead of the HDhomerun app on the same channels. AppleTV4k does not crash at all.

nickk
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Re: AC-4 Audio - talkenrain

Post by nickk »

102 and 106 should work with the 20210110 app releases for Windows 10, XBox One, Apple TV 4K, and iOS.

Android and FireTV app updates will be released tomorrow.

Nick

talkenrain
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Re: AC-4 Audio - talkenrain

Post by talkenrain »

nickk wrote: Sun Jan 10, 2021 1:10 pm 102 and 106 should work with the 20210110 app releases for Windows 10, XBox One, Apple TV 4K, and iOS.

Android and FireTV app updates will be released tomorrow.

Nick
Great news. It hasn't shown up in the Apple store yet but I'll look forward to it and report back asap.
THANKS !!!

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