Hi Panos, Hi Marc,
just a side note... some years ago read of the *.caf format.
Its no smaller than wav, but aside of this fact - wouldn't it be a
perfect choice for (long) ambiX content?
Back then it wasn't possible to use it outside of the appleversum.
In the meantime things changed and it can be read by FFMPEG and Reaper...
Best,
Gabriel
Am 01.05.23 um 00:43 schrieb Marc Lavallée:
Hi Panos,
Thanks for trying!
My personal choice is to use the WavPack codec; it was proposed for
the ambiX format:
https://ambisonics-symposium.org/Members/zotter/copy_of_publications/publications/2011_NachbarZotterSontacchiDeleflie_ambix.pdf
I think it's still a valid choice (even if professionals use WAV or
AIFF).
Marc (also an Ambisonics hobbyist).
Le 2023-04-30 à 18 h 27, Panos Kouvelis a écrit :
Hi Marc,
You're right, I thought that this would be easy but I passed the last
hour trying like you and also with flac.exe command line tool using
the -ogg flag.
I used a 16 channel file and the error from the flac utility was that
it wasn't a wavefile extensible and couldn't mark channels, so I
opened my test file using Audition and defined the wavefile
extensible as higher order ambisonics, after that the error I got
from the flac encoder was unsupported number of channels.
I don't really know how this can be done :-(
If you have any news please let me know.
Cheers!
*Pan Athen*
SoundFellas <https://soundfellas.com/>, *MediaFlake Ltd
<http://mediaflake.com/>**
*
Digital Media Services, Content, and Tools
On Sun, Apr 30, 2023 at 10:00 PM Marc Lavallée <m...@hacklava.net>
wrote:
Hi Panos,
The Ogg FLAC documentation does not mention that more than 8
channels
can be encoded.
I tried using ffmpeg; this is working for 8 channels:
ffmpeg -f lavfi -i "anoisesrc=d=1:c=pink:a=0.5" -c:a flac -f ogg
-ac 8
-y noise-8c.ogg
But this is not working for 16 channels:
ffmpeg -f lavfi -i "anoisesrc=d=1:c=pink:a=0.5" -c:a flac -f ogg
-ac 16
-y noise-16c.ogg
The returned error is: "[flac @ 0x562603bd8540] 16 channels not
supported (max 8)"
And when specifying a channel number higher than 8 but lower than
16,
the result is a mono file.
It could be that ffmpeg is not capable of encoding more than 8
channels
for FLAC streams.
What tool (or method) would you suggest to encode more than 8
channels
in a Ogg container?
Marc
Le 2023-04-30 à 14 h 11, Panos Kouvelis a écrit :
> Native FLAC can support up to 8 channels; you are right.
>
> To support more channels using FLAC, you should use Ogg FLAC,
an OGG
> container containing FLAC-encoded material.
>
> If that helps you, you can find more here:
> https://xiph.org/flac/faq.html#general__native_vs_ogg
> Here: https://xiph.org/flac/faq.html#general__native_or_ogg
> And here: https://xiph.org/flac/ogg_mapping.html
>
> I hope that helps in your case.
>
> Cheers!
>
> *Pan Athen*
> SoundFellas <https://soundfellas.com/>, *MediaFlake Ltd
> <http://mediaflake.com/>*
> Digital Media Services, Content, and Tools
>
>
> On Sun, Apr 30, 2023 at 9:02 PM Bo-Erik Sandholm
<bosses...@gmail.com>
> wrote:
>
>> Can someone comment on the double message i think i find in the
spec?
>>
>> There is a the specification of max number of channels in
stream info
>> chapter 8.2
>>
>> u(3) | (number of channels)-1. FLAC supports from 1 to |
>> | | 8 channels.
>>
>>
>> In chapter 8.6.2
>>
>> A WAVEFORMATEXTENSIBLE_CHANNEL_MASK field of 0x0 can be used to
>> indicate that none of the audio channels of a file
correlate with
>> speaker positions. This is the case when audio needs to be
decoded
>> into speaker positions (e.g. Ambisonics B-format audio) or
when a
>> multitrack recording is contained.
>>
>>
>> .....
>>
>> What does this mean?
>>
>> Is it that ambisonics cannot be streamed in second or third
order with
>> flac?
>>
>>
>> In todays widebandwith internet this feels a bit too
restrictive, is
>> it a Dolby business thing?
>>
>>
>> https://datatracker.ietf.org/doc/draft-ietf-cellar-flac/
>>
>> Any information or ideas about this?
>>
>> Bosse Sandholm
>> Ambisonics hobbyist.
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<https://mail.music.vt.edu/mailman/private/sursound/attachments/20230430/25f247c0/attachment.htm>
_______________________________________________
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe
here, edit account or options, view archives and so on.
_______________________________________________
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit
account or options, view archives and so on.
