H265 Encoder ignoring Mono?

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AdrianH
Posts: 87
Joined: Thu Jul 18, 2019 2:46 pm

H265 Encoder ignoring Mono?

Post by AdrianH » Sun Mar 21, 2021 10:58 am

I hope someone can assist my understanding of the encoder box. No matter what the stream settings I use, the output always seems to be with Stereo audio at a sample rate of 44100Hz, I see the bitrate can vary.

What I do not understand is the settings in the Browser audio tab for the box. These can be 48K 64K 128K 256K MONO and Stereo and when the box is set for mono at 48K I still see a video stream with stereo audio.

It is as if the box ignores the mono or stereo settings.

So if someone can explain what is happening I would be grateful.

I have been playing with a script in the F5OEO 0303 firmware but sending the output of the H265 encoder box to my PC as a UDP stream to check out. This with video being sent from OBS using the box as a monitor.

Perhaps I have missed something else, but any help is appreciated as to why the box is doing what it is.

Adrian

M0DTS
Posts: 653
Joined: Sun Feb 24, 2008 9:03 pm

Re: H265 Encoder ignoring Mono?

Post by M0DTS » Sun Mar 21, 2021 11:22 am

Hi Adrian

Yes i believe this is correct. The Bitrate seems to work but not the mono option.
It may have worked on boxes with very old firmware but I don't have a box with it on now to try with...

This is based on using the Line input, i don't use HDMI audio input as it's rather intermittent from my PC...
By the way, on Firmware other than 1.60.190919, the Line input is MONO but feeds the same audio input to both left and right of the STEREO encoded output.

I guess the only answer is to alter the ffmpeg remux command line on the pluto to only send one audio channel...

Rob

AdrianH
Posts: 87
Joined: Thu Jul 18, 2019 2:46 pm

Re: H265 Encoder ignoring Mono?

Post by AdrianH » Sun Mar 21, 2021 11:49 am

Hello Rob

Thanks for responding, I will say here I am a poke and hope person when it comes to programming languages, so sometimes when things go wrong it is me, I can only really modify and test other peoples programs.

I am using the HDMI audio input and the firmware is back to a non-patched ENC_V2.38.201216. I had some version 1.XX in there originally.

I got myself confused at first wondering about the 44100 sample rate before realising that was different to the encoded bit rate.

It is just that the screen displays within the encoder web page follow the commands, but the output did not. So the fault is in the encoder, I will have to telnet in the box and have a look around.

Cheers

Adrian

AdrianH
Posts: 87
Joined: Thu Jul 18, 2019 2:46 pm

Re: H265 Encoder ignoring Mono?

Post by AdrianH » Tue Apr 13, 2021 9:26 pm

Just to update on the Stereo/Mono from the box. I took Robs suggestion literally on using ffmpeg.

Mine is a simple system, by today's standards a low power PC, Encoder box and Pluto. So I spent several days trying to figure out the main part of F5OEO version 0303 using my best poke and hope skills and trying to learn more about how it's done. Mainly by reading the existing code trying to figure what is happening (books and google) and then make it do what I want. So I think I am on patch version 11 by now, but have managed to stream reasonably well from 500KS down to 66KS. Only taken me a three days, but that's progress for me.

Adrian

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