AC-4 Audio?

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ferrellsl
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Re: AC-4 Audio?

Post by ferrellsl »

I've completed a build of the QMPlay2 app for 64-bit Windows that supports HEVC with AC-4 audio. See https://github.com/zaps166/QMPlay2 for more info about QMPlay2.

QMPLAY2 supports playback of local files as well as URL streams such as those from your HDHomeRun 4k tuners. It also has an equalizer, FFT spectrum, supports subtitles and lyrics.

This is a portable build. Once you've extracted the app to your hard drive, run the QMPlay2.exe but do not allow it to update itself as this will break AC-4 audio. Go to Options->Settings and remove the checkmark that says "Automatically check and download updates".

No, I will not build a Linux/MacOS version nor will I build a version for 32-bit Windows.

You can download this modified version of QMPLAY2 from here: https://www.dropbox.com/s/nidx6vaquxx7j ... 2.zip?dl=0

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Last edited by ferrellsl on Wed Sep 08, 2021 9:54 pm, edited 1 time in total.

ferrellsl
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Re: AC-4 Audio?

Post by ferrellsl »

For folks who want something a bit more light weight than QMPlay2, you can try this player. It's barebones and plays local files and URL streams (with HEVC/AC-4 audio support of course). This is another 64-bit Windows app and is based on the the player found here: https://github.com/yundiantech/VideoPlayer

When feeding it a URL, be patient and wait a bit for the video to start playing. It can take up to 20 seconds before the stream plays after providing a working URL.

Again, if you want a Linux/MacOS version or a 32-bit Windows build you're welcome to roll your own from the sources at github.

I use NextPVR to schedule my HEVC/AC4 recordings from my Silicon Dust tuner and use this player or QMPlay2 for playback since Windows doesn't have native AC-4 audio support.

You can download the installer for this light weight player here: https://www.dropbox.com/s/cx2tm3f4i4whg ... p.exe?dl=0

jasonl
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Re: AC-4 Audio?

Post by jasonl »

bobchase wrote: Wed Sep 08, 2021 10:54 am
jasonl wrote: Tue Sep 07, 2021 6:09 pm
bobchase wrote: Mon Sep 06, 2021 11:47 am
112.1 (NBC) is down due to an interstation connection problem.
110.1 (FOX) should come in for you as it is working for Silicon Dust tuners as well as the TV's.
I'm curious, what format are the video and audio in when bouncing from station to station?
121.1 is being sent out 1080p60
110.1 is being sent at 720p60
I'm asking about the inter-station link before it actually gets encoded for broadcast. Is KPNX sending out 1080i in some uncompressed HD-SDI type format over fiber that eventually reaches KASW, where it gets upconverted to 1080p and encoded to HEVC? Some sort of intermediate compression format? I remember the the later days of analog TV when there was a fiber loop running around town linking up all the major stations plus Cox (or was it still Dimension?) so that cable viewers got a cleaner feed that didn't go down when a transmission line burned out or someone had to relamp their tower.

bobchase
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Re: AC-4 Audio?

Post by bobchase »

jasonl wrote: Thu Sep 09, 2021 5:30 pm
bobchase wrote: Wed Sep 08, 2021 10:54 am
jasonl wrote: Tue Sep 07, 2021 6:09 pm
I'm curious, what format are the video and audio in when bouncing from station to station?
121.1 is being sent out 1080p60
110.1 is being sent at 720p60
I'm asking about the inter-station link before it actually gets encoded for broadcast. Is KPNX sending out 1080i in some uncompressed HD-SDI type format over fiber that eventually reaches KASW, where it gets upconverted to 1080p and encoded to HEVC? Some sort of intermediate compression format? I remember the the later days of analog TV when there was a fiber loop running around town linking up all the major stations plus Cox (or was it still Dimension?) so that cable viewers got a cleaner feed that didn't go down when a transmission line burned out or someone had to relamp their tower.
I can't tell you the amount of compression or the datarate between KPNX and KSAZ but it certainly wouldn't be uncompressed as there is only about 100 Mbps available to move a 1.5 Gbps feed. After KPNX is encoded to DASH, along with KSAZ and KUPT, they are then sent over to KASW for ROUTE encapsulation, signaling and scheduling.

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