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Arian
15th June 2021, 04:47
I've just been itching to make a post on this forum, but there was a waiting period to do so. I tried going on other sites in the meantime to pose the following inquiry but to no avail!

So, to make a long story short, AVerMedia capture cards are able to capture Dolby Digital noise in PCM format and it can be successfully be converted to bit-perfect AC3 DD 5.1 audio.

Personally, I go with this simple command, and it would work every time: besplit -core -input 1.wav -type ddwav -output 1.ac3

Unfortunately though, AVerMedia's drivers have rendered the capture card I was using (Extremecap U3) pretty useless.

I replaced it with an open-source, plug and play capture card, the Inogeni 4K2USB3. However, the conversion generates some... unsavoury results.

It sounds the same on paper: https://twitter.com/MantaMorty/status/1402830287332069376?s=20

But post-conversion, it's a LOT different: https://twitter.com/i/status/1402830530316492800

I'm told that this happens because the Inogeni card(s) re-sample the audio which is why the converted audio comes out messed up/corrupted.

So, before I invest in yet another capture card, I'd like to get some confirmation that it WILL work with BeSplit for my type of audio work.

I was keen towards the Elgato HD60 S, since it also has uncompressed capture capabilities, but I want you guys to let me know; If you do this kind of thing that I'm speaking of, what capture card are you doing it with?

Heck, you don't even have to know first-hand, any insight would be great.

Thanks, guys.

tebasuna51
15th June 2021, 10:51
...
It sounds the same on paper: https://twitter.com/MantaMorty/status/1402830287332069376?s=20

But post-conversion, it's a LOT different: https://twitter.com/i/status/1402830530316492800

We need the files (mediafire, sendspace,...), not a twiter play.

Arian
15th June 2021, 14:11
We need the files (mediafire, sendspace,...), not a Twitter play.

Okay, my apologies.

.wav file: https://drive.google.com/file/d/1IYVwyY1gL7wRn7gmqp8WGkmVuiiCS1tC/view?usp=sharing

.ac3 file: https://drive.google.com/file/d/1n4m6LDXtUFrFZrMND0TqIFLsvZQyzmsK/view?usp=sharing

tebasuna51
15th June 2021, 23:26
The file is corruput, the data does not make sense:

File ........: C:\Downloads\1.wav
Size ........: 4038424 bytes

---------------------------------------------- Header Info
ChunkID .....: RIFF
RiffLength ..: 36 (ERROR: Must be Size - 8 = 4038416)
Container ...: WAVE
SubchunkID ..: fmt (Length: 16)
AudioFormat .: 1 (Integer)
NumChannels .: 2
SampleRate ..: 48000
ByteRate ....: 192000
BlockAlign ..: 32
BitsPerSample: 16 (WARNING: BlockAlign <> NumChannels x BistPerSample / 8 = 4)
SubchunkID ..: data (Length: 4038384)
Offset data .: 44 (WARNING: Audio data truncated: -4 bytes)
Duration ....: 21.03323 sec., (0h. 0m. 21.03323s.)
------------------------------------------------- End Info

Tested with eac3to:

eac3to v3.34
command line: "C:\Portable\eac3to\eac3to.exe" "C:\tmp\1(1).pcm" -progressnumbers -log="C:\Portable\eac3to\UsEac3to\UsEac3To.log"
------------------------------------------------------------------------------
This might be a RAW/PCM file. Trying to figure out the details.
This will probably take a while. Please be patient...
The RAW/PCM file seems to be little endian.
The RAW/PCM file seems to have a bitdepth of 16 bits.
The RAW/PCM file probably has 1, 2, 3, 4 or 5 channels.
The most probable number of channels is 1.
Please specify one of these via command line paramater.

None of number of channels output a coherent audio.

SeeMoreDigital
16th June 2021, 09:51
@Arian,

Out of interest... What audio capture options does your AVerMedia capture card offer?

Arian
17th June 2021, 03:16
The file is corruput, the data does not make sense:

File ........: C:\Downloads\1.wav
Size ........: 4038424 bytes

---------------------------------------------- Header Info
ChunkID .....: RIFF
RiffLength ..: 36 (ERROR: Must be Size - 8 = 4038416)
Container ...: WAVE
SubchunkID ..: fmt (Length: 16)
AudioFormat .: 1 (Integer)
NumChannels .: 2
SampleRate ..: 48000
ByteRate ....: 192000
BlockAlign ..: 32
BitsPerSample: 16 (WARNING: BlockAlign <> NumChannels x BistPerSample / 8 = 4)
SubchunkID ..: data (Length: 4038384)
Offset data .: 44 (WARNING: Audio data truncated: -4 bytes)
Duration ....: 21.03323 sec., (0h. 0m. 21.03323s.)
------------------------------------------------- End Info

Tested with eac3to:

eac3to v3.34
command line: "C:\Portable\eac3to\eac3to.exe" "C:\tmp\1(1).pcm" -progressnumbers -log="C:\Portable\eac3to\UsEac3to\UsEac3To.log"
------------------------------------------------------------------------------
This might be a RAW/PCM file. Trying to figure out the details.
This will probably take a while. Please be patient...
The RAW/PCM file seems to be little endian.
The RAW/PCM file seems to have a bitdepth of 16 bits.
The RAW/PCM file probably has 1, 2, 3, 4 or 5 channels.
The most probable number of channels is 1.
Please specify one of these via command line paramater.

None of number of channels output a coherent audio.

Yeah, I thought as much. I think it has something to do with the fact that Inogeni claims to have the most bit-perfect audio capture capacity, but clearly they've just upsampled everything in the worst way. Thanks for your input.

Arian
17th June 2021, 03:18
@Arian,

Out of interest... What audio capture options does your AVerMedia capture card offer?

@SeeMoreDigital, I'm glad you asked.

They have a few very lossy options when you use RECentral, their company produced and "recommended" capture software, but when using AmarecTV or VirtualDub, you just get the standard uncompressed 48kHz option and that's it.

Do you think that's all I would need to get it to work with another brand?

SeeMoreDigital
17th June 2021, 09:45
...but when using AmarecTV or VirtualDub, you just get the standard uncompressed 48kHz option and that's it.

Do you think that's all I would need to get it to work with another brand?A 'Sample Rate' of 48kHz is perfect for Dolby Digital.

What is not right is the captures 'byte rate' which (according to tebasuna51's report) is '192,000'. Which is way too high!

The 'byte rate' of a lossy Dolby Digital stream does not need to be any higher that '80,000' (ie: 640 Kbps).


Cheers

Arian
17th June 2021, 12:01
A 'Sample Rate' of 48kHz is perfect for Dolby Digital.

What is not right is the captures 'byte rate' which (according to tebasuna51's report) is '192,000'. Which is way too high!

The 'byte rate' of a lossy Dolby Digital stream does not need to be any higher that '80,000' (ie: 640 Kbps).


Cheers

That's awesome information, SMD!

If you have any prime examples of HDMI USB cards that would record in a sample rate of 48kHz, that would basically solve my dilemma here! :D

SeeMoreDigital
17th June 2021, 22:52
Please read my post again?

Arian
18th June 2021, 06:15
Please read my post again?

I did, I was just asking if you had any confirmation on any capture cards that are guaranteed to record in 48kHz. You saying that the byte rate shouldn't exceed 80,000 doesn't answer that.

SeeMoreDigital
18th June 2021, 08:19
As I mentioned previously...

According to tebasuna51's report it would appear that your capture device is already able to capture at 48kHz... It's the 'byte rate' that's too high. It needs lowering to 80,000.

SquallMX
18th June 2021, 18:14
I have an Extremecap U3, with older drivers it works like a charm, and Dolby and DTS support are fine.

Arian
20th June 2021, 05:34
As I mentioned previously...

According to tebasuna51's report it would appear that your capture device is already able to capture at 48kHz... It's the 'byte rate' that's too high. It needs lowering to 80,000.

I don't have a screenshot to support it, but I did have it set to 48kHz. It would appear, after reading tebasuna51's post here that my capture card just defaults to 192kHz so matter what I choose anyway.

Arian
20th June 2021, 05:35
I have an Extremecap U3, with older drivers it works like a charm, and Dolby and DTS support are fine.

Could I possibly see these drivers? If they're the ones on VideoHelp, they've outlived their usefulness, at least for me.

SquallMX
20th June 2021, 18:03
Could I possibly see these drivers? If they're the ones on VideoHelp, they've outlived their usefulness, at least for me.

Im using "Win10_x64_V1.0.64.33" newer versions remove DTS/AC3 audio capture support for me, any reason for not using them?

Arian
21st June 2021, 07:40
Im using "Win10_x64_V1.0.64.33" newer versions remove DTS/AC3 audio capture support for me, any reason for not using them?

By default, I get this screen, even with a non-HDCP compliant HDMI splitter:

https://d22tfas1vlww24.cloudfront.net/avermedia/files/a1cf4ce6472ff391215214c03d5dcfdc.jpg

At times, uninstalling one driver and installing another works temporarily, but this is a constant and isn't always foolproof. Sometimes, you just just a black screen with no responsiveness whatsoever.

So, ideally I'd like the name of a capture card where this whole operation isn't necessary.

sebus
13th February 2022, 19:31
Magewell Pro Capture HDMI (https://www.magewell.com/products/pro-capture-hdmi) will do perfectly fine

sebus
26th February 2022, 16:14
As will do cheap Hifime UR23 SPDIF Optical to USB converter (https://hifimediy.com/product/hifime-ur23-spdif-optical-to-usb-converter/) and Audacity build with ASIO