Re: [Sursound] Ambisonics for Android and also Oculus..

[Courville, Daniel]

Le 16-04-05 07:05, Courville, Daniel a écrit :

>Le 16-04-04 17:42, Courville, Daniel a écrit :
>
>>So it seems that there's a gain error in the O channel of the ambiX converter.
>
>There will be a new release of ambiX in a few days fixing this problem.

The new version is now available: http://www.matthiaskronlachner.com/?p=2015

Thanks Matthias!
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Re: [Sursound] Ambisonics for Android and also Oculus..

[Courville, Daniel]

Le 16-04-04 17:42, Courville, Daniel a écrit :

>So it seems that there's a gain error in the O channel of the ambiX converter.

There will be a new release of ambiX in a few days fixing this problem. Thanks 
Matthias!
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Re: [Sursound] Ambisonics for Android and also Oculus..

[Courville, Daniel]

Fons Adriaensen wrote:

> On Mon, Apr 04, 2016 at 12:47:14PM +, Courville, Daniel wrote:

>> Going from FuMa to N3D, the maximum gain you should see is 3.416 linear (+ 
>> 10.67 dB) in the O channel.

> AFAIK that should be 2.646, +8.45 dB, for K.

So it seems that there's a gain error in the O channel of the ambiX converter.

Here's a comparison between the ambiX converter and Blue Ripple Sound "TOA 
Decoder - N3D/SN3D":

for FuMa to SN3D
http://www.radio.uqam.ca/ambisonic/images/fuma-sn3d-ambix-brs.png

for FuMa to N3D
http://www.radio.uqam.ca/ambisonic/images/fuma-n3d-ambix-brs.png

- Daniel
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Re: [Sursound] Ambisonics for Android and also Oculus..

[Fons Adriaensen]

On Mon, Apr 04, 2016 at 12:47:14PM +, Courville, Daniel wrote:

> Going from FuMa to N3D, the maximum gain you should see is 3.416 linear (+ 
> 10.67 dB) in the O channel.

AFAIK that should be 2.646, +8.45 dB, for K.

Ciao,

-- 
FA

A world of exhaustive, reliable metadata would be an utopia.
It's also a pipe-dream, founded on self-delusion, nerd hubris
and hysterically inflated market opportunities. (Cory Doctorow)

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Re: [Sursound] Ambisonics for Android and also Oculus..

[Courville, Daniel]

Albert Leusink wrote:

> 1. Does it make any difference in what order (1st or 3rd or higher...) you 
> convert from FuMa to ACN/SN3D ?

I would say no.

> 2. I noticed an increase in overall gain of about 4.5dB going from Fuma to 
> ACN/SN3D, both in 1st order and 3r order conversion. Is this to be expected 
> or is this plugin-related (Ambix VST converter 0.2.5) ?

Using the Kronlachner Ambix 3rd order converter, going from FuMa to SN3D, the 
maximum gain you should see is 1.414 linear (+ 3 dB) in the W channel and 1.291 
linear (+ 2.2 dB) in the O channel. The other channels are either identical or 
have lower gains.

http://www.radio.uqam.ca/ambisonic/images/fuma-sn3d.png

Going from FuMa to N3D, the maximum gain you should see is 3.416 linear (+ 
10.67 dB) in the O channel.

http://www.radio.uqam.ca/ambisonic/images/fuma-n3d.png

Going from SN3D to N3D, the gain is 1.732 (+ 4.77 dB) for the 1st order, 2.236 
(+ 7 dB) for the 2nd order and 2.646 (+ 8.45 dB) for the 3rd order.

http://www.radio.uqam.ca/ambisonic/images/sn3d-n3d.png

- Daniel

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Re: [Sursound] Ambisonics for Android and also Oculus..

[Dave Malham]

I would just like to emphasise that Stefan is absolutely right when he says
"B format 1st order was not based on "FuMa conventions", it is obviously
the other way around. ". Richard and I were looking at extending the naming
of channels  up to third order in a way that respected the conventions of
the original B Format when we announced the scheme in 2000.

   Dave

It is worth noting that there weren't even any VST plugins for Ambisonics
at that point.  Blimey, that makes me feel ancient :-(

  Dave

On 3 April 2016 at 18:57, Stefan Schreiber  wrote:

> Xavier Bonjour wrote:
>
> Hello,
>>
>> And to add one more level of confusion, MPEG-H 3D Audio has gone for
>> ACN/N3D normalization!
>>
>>
>
> Ah, I didn't read this before. Thanks!
>
> Even if so, MPEG-H 3D Audio is not really an Ambisonics format in a strict
> sense. (It is maybe a hybrid codec accepting different input formats, and
> reproducing C/O and HOA on different speaker configurations and via
> headphones.)
>
> If MPEG-H 3D Audio uses ACN/N3D conventions, it is more an < internal
> problem > for their HOA decoder(s) - and doesn't really matter to other
> people.
>
> AmbiX is a stand-alone format developped  for HOA.
>
> B format 1st order was not based on "FuMa conventions", it is obviously
> the other way around. (Original convention and format for 1st order SF
> recordings and mixes.)
>
> Best regards,
>
> Stefan
>
>
>
> Going beyond 3rd order  is also going for better quality and it makes
>> sense for the following reasons:
>>
>> - Recording technologies make progress: we should expect multicapsules
>> microphone technology to improve and go beyond 3rd Order
>> - 3D sound can also be computer generated to any order and there is a
>> significant perceptual difference between the binaural rendering of 3rd
>> order content and content of higher orders. And this difference is even
>> bigger when HRTF are personalized
>> - Compression (MPEG-H 3D Audio,  ...)  will make HOA content manageable,
>> even on a smartphone.
>>
>> I guess defining a normalization that covers HOA beyond 3rd order is about
>> getting the "format" ready for the future development.
>>
>> Kind regards
>>
>> -Xavier
>>
>>
>>
>> -Original Message-
>> From: Sursound [mailto:sursound-boun...@music.vt.edu] On Behalf Of Albert
>> Leusink
>> Sent: dimanche 3 avril 2016 02:20
>> To: sursound@music.vt.edu
>> Subject: [Sursound] Ambisonics for Android and also Oculus..
>>
>>
>> Hello all,
>>
>> Coming soon, to a phone near you !:
>>
>> https://storage.googleapis.com/jump-inspector/Jump_Inspector_Quick_Start.p
>> df
>>
>> There will definitely be many user complaints initially due to
>> misunderstandings as it uses ACN/SN3D ordering and 99% of all the tools
>> (VST plugins etc..) currently used by the VR community are FuMa / .AMB
>> based...
>>
>> To add to that confusion, Oculus has just updated their Gear VR video
>> player specs to accept FuMa first order
>>
>> I'm sure you have all had this discussion many times over, but what, if
>> any, are the advantages of 1st order ACN over FuMa?
>>
>> From what I've gathered, ACN was initially proposed as it would allow
>>>
>> bigger file sizes but I don't think that really applies to mobile phones
>> in this case...doesn't it only make sense to have ACN beyond 3rd order?
>>
>>
>>
>> Have a good weekend,
>>
>>
>> Albert
>>
>>
>>
>>
>>
>> ___
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>>
>>
>>
>
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-- 

As of 1st October 2012, I have retired from the University.

These are my own views and may or may not be shared by the University

Dave Malham
Honorary Fellow, Department of Music
The University of York
York YO10 5DD
UK

'Ambisonics - Component Imaging for Audio'
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Re: [Sursound] Ambisonics for Android and also Oculus..

[Albert Leusink]

Thank you all,

It's an honor to have access to so much great knowledge, from the comfort of
one's home...

I'm sure many of you have believed in Ambisonics for a long time and are
excited (or maybe dissapointed..) that it's finally getting its' well
deserved turn in the spotlight.

Let's hope that the format issues will be settled sooner than later.
We will definitely need some more tools (plugins, converters etc.) for the
ACN format, so whomever the shoe fits...

Two more issues:

1. Does it make any difference in what order (1st or 3rd or higher...) you
convert from FuMa to ACN/SN3D ?


2. I noticed an increase in overall gain of about 4.5dB going from Fuma to
ACN/SN3D, both in 1st order and 3r order conversion. Is this to be expected
or is this plugin-related (Ambix VST converter 0.2.5) ?


Regards,

Albert






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Re: [Sursound] Ambisonics for Android and also Oculus..

[Stefan Schreiber]

Fons Adriaensen wrote:


On Sun, Apr 03, 2016 at 11:05:59AM +, Politis Archontis wrote:

 


Oops, that should have been “About N3D…” instead of “About ACN...”
   



Modulo that correction, that's probably something that anyone who
has ever done any maths related to HOA decoding, beamforming,
rotation, etc. will confirm without any reservation. 


Another matter: what is the 'official' definition of IEM's
Ambix format ? Problem is that I find contradicting info.

There's the paper: 




and the source code on Github:



These mention different UUIDs for the extended (with matrix) format.
Also in the paper it is at least suggested (Fig. 1) that the matrix
dimensions are 32-bit floating point, while the code uses 32-bit
integers (which makes sense).


 

1. I honestly hope that Google IT developpers will be aware of any of 
such "issues".   < g >


2. Shows that you should not use anyything just because it is new. ("to 
replace an outdated 1st order format"; Google proposes AmbiX for 
FOA-only application!)


3. Alas, seems to be an overkill solution -  compared to B format/FOA.

Best,

Stefan






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Re: [Sursound] Ambisonics for Android and also Oculus..

[Stefan Schreiber]

Xavier Bonjour wrote:


Hello,

And to add one more level of confusion, MPEG-H 3D Audio has gone for
ACN/N3D normalization!
 



Ah, I didn't read this before. Thanks!

Even if so, MPEG-H 3D Audio is not really an Ambisonics format in a 
strict sense. (It is maybe a hybrid codec accepting different input 
formats, and reproducing C/O and HOA on different speaker configurations 
and via headphones.)


If MPEG-H 3D Audio uses ACN/N3D conventions, it is more an < internal 
problem > for their HOA decoder(s) - and doesn't really matter to other 
people.


AmbiX is a stand-alone format developped  for HOA.

B format 1st order was not based on "FuMa conventions", it is obviously 
the other way around. (Original convention and format for 1st order SF 
recordings and mixes.)


Best regards,

Stefan




Going beyond 3rd order  is also going for better quality and it makes
sense for the following reasons:

- Recording technologies make progress: we should expect multicapsules
microphone technology to improve and go beyond 3rd Order
- 3D sound can also be computer generated to any order and there is a
significant perceptual difference between the binaural rendering of 3rd
order content and content of higher orders. And this difference is even
bigger when HRTF are personalized
- Compression (MPEG-H 3D Audio,  ...)  will make HOA content manageable,
even on a smartphone.

I guess defining a normalization that covers HOA beyond 3rd order is about
getting the "format" ready for the future development.

Kind regards

-Xavier



-Original Message-
From: Sursound [mailto:sursound-boun...@music.vt.edu] On Behalf Of Albert
Leusink
Sent: dimanche 3 avril 2016 02:20
To: sursound@music.vt.edu
Subject: [Sursound] Ambisonics for Android and also Oculus..


Hello all,

Coming soon, to a phone near you !:

https://storage.googleapis.com/jump-inspector/Jump_Inspector_Quick_Start.p
df

There will definitely be many user complaints initially due to
misunderstandings as it uses ACN/SN3D ordering and 99% of all the tools
(VST plugins etc..) currently used by the VR community are FuMa / .AMB
based...

To add to that confusion, Oculus has just updated their Gear VR video
player specs to accept FuMa first order

I'm sure you have all had this discussion many times over, but what, if
any, are the advantages of 1st order ACN over FuMa?


From what I've gathered, ACN was initially proposed as it would allow

bigger file sizes but I don't think that really applies to mobile phones
in this case...doesn't it only make sense to have ACN beyond 3rd order?



Have a good weekend,


Albert





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Re: [Sursound] Ambisonics for Android and also Oculus

[Stefan Schreiber]

Courville, Daniel wrote:


Albert Leusink wrote:

 


I'm sure you have all had this discussion many times over, but what, if any,
are the advantages of 1st order ACN over FuMa?
   



http://www.blueripplesound.com/n3d


 

We recommend that N3D be stored using the ACN channel ordering 
sequence (see http://ambisonics.ch/standards/channels/). But be 
careful - although most software seems to use this convention, there 
are variants out there, so you may need to reorder or modify your 
channels.



This is NOT AmbiX format.

https://en.wikipedia.org/wiki/Ambisonic_data_exchange_formats

As N3D and SN3D differ only by scaling factors, care is needed when 
working with both, as it may not be obvious on first listening if an 
error has been made, particularly on a system with a small number of 
speakers.




Happy confusion!

St.

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Re: [Sursound] Ambisonics for Android and also Oculus..

[Stefan Schreiber]

Albert Leusink wrote:


Hello all,

Coming soon, to a phone near you !:

https://storage.googleapis.com/jump-inspector/Jump_Inspector_Quick_Start.pdf

There will definitely be many user complaints initially due to
misunderstandings as it uses ACN/SN3D ordering and 99% of all the tools (VST
plugins etc..) currently used by the VR community are FuMa / .AMB based...
 



I certainly would "vote" to keep B format at 1st order, because this is 
the already established format for SF mikes and 1st order recordings. As 
Albert writes, available 1st order tools use and expect B format.


It is probably a possible or even good idea to use Ambix (ACN ordering, 
SN3D) as consistent format for < HOA >.


I believe this proposal is pretty consistent with Mpeg-3DA 
standardization, anyway. (Ambisonics in 3DA is mostly about HOA 
compression. Not "FOA compression".)


B format for 2nd and 3rd order is not a lot in (practical) use yet, and 
could still be replaced by a more general scheme and format.


To insist on a retrospective format change for an in-use format (B 
format/FOA) doesn't make a lot of sense at all.



Google has also problems to support 5.1 on YT in any proper or 
systematic way. To propose Ambix as 1st order format is caused probably 
just by lack of real understanding, and I would assume there was no real 
discussion about this subject anyway.


Note that Google supports only "Quad (4.0/4-channel) layout with 
ambisonic audio". Nothing else. So, this "thing" is about 1st order, not 
HOA (>=2nd order). Google also doesn't give any explicit reason why 
AmbiX should be used at 1st order, and not B format.

Who else here uses AmbiX at 1st order? Anybody?!

I don't know why this "Jump Inspector" experiment is supposed to be 
based on Mac OS X and "supported high end Android devices", as well. (A 
normal "practical" effort would be to support multichannel 
audio/Ambisonics in "Android of version number x.y or above".)



Best regards,

Stefan

P.S.:


To add to that confusion, Oculus has just updated their Gear VR video player
specs to accept FuMa first order
 

Exactly! They actually < use > Ambisonics, and SF mikes...  This case is 
not about "experiments", as this VR video player just works. (And 
additionally, Oculus has some real and unquestionable technical 
expertise in this field...)



I'm sure you have all had this discussion many times over, but what, if any,
are the advantages of 1st order ACN over FuMa?
 

Not any. So it is probably about convention, tradition. Systematic 
consistency is a valid aim -  but not if ignoring about 40 years of 
former history and practice!



From what I've gathered, ACN was initially proposed as it would allow bigger

file sizes but I don't think that really applies to mobile phones in this
case...doesn't it only make sense to have ACN beyond 3rd order?
 



AmbiX/ACN maybe at >= 2nd order. B format has been < always > used at 
1st order, though.


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Re: [Sursound] Ambisonics for Android and also Oculus

[Courville, Daniel]

Albert Leusink wrote:

>I'm sure you have all had this discussion many times over, but what, if any,
>are the advantages of 1st order ACN over FuMa?

http://www.blueripplesound.com/n3d

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Re: [Sursound] Ambisonics for Android and also Oculus..

[Fons Adriaensen]

On Sun, Apr 03, 2016 at 11:05:59AM +, Politis Archontis wrote:

> Oops, that should have been “About N3D…” instead of “About ACN...”

Modulo that correction, that's probably something that anyone who
has ever done any maths related to HOA decoding, beamforming,
rotation, etc. will confirm without any reservation. 

Another matter: what is the 'official' definition of IEM's
Ambix format ? Problem is that I find contradicting info.

There's the paper: 



and the source code on Github:



These mention different UUIDs for the extended (with matrix) format.
Also in the paper it is at least suggested (Fig. 1) that the matrix
dimensions are 32-bit floating point, while the code uses 32-bit
integers (which makes sense).

Ciao,

-- 
FA

A world of exhaustive, reliable metadata would be an utopia.
It's also a pipe-dream, founded on self-delusion, nerd hubris
and hysterically inflated market opportunities. (Cory Doctorow)

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Re: [Sursound] Ambisonics for Android and also Oculus..

[Politis Archontis]

Oops, that should have been “About N3D…” instead of “About ACN...”

I agree with Fons that there isn’t much reason for multiple inconsistent 
definitions, especially in the case of HOA, and then even first-order can be 
treated in the same framework. There is the intuitive ‘XYZ’ interpretation of 
first-order signals (which disappears altogether already from second order), 
which is probably useful for design of first-order systems, but that doesn’t 
mean that the signals cannot be stored in a more universal ACN/(S)N3D format, 
and convert the B-format tools to handle the ACN signals internally. It is just 
re-arranging of channels and a scaling in the end.

Regards,
Archontis

On 03 Apr 2016, at 13:29, Politis Archontis 
> wrote:

The advantage of ACN is that it is a natural ordering of the HOA channels 
described with a single number q=n^2+n+m+1 (with n the order and m the degree), 
and it is aligned with pretty much any other field using spherical spectral 
analysis (graphics, signal processing, physics, etc...) , making transfer of 
knowledge from these fields to ambisonics much less confusing.

About ACN, if you are working on the more theoretical side of ambisonics, it is 
the only normalization that makes sense again since it keeps the spherical 
harmonics orthonormal and it simplifies most things on paper a lot! It can just 
as well be kept as a standard, however conversion to other normalizations (such 
as SN3D) are just a gain factor per order and very easy to do.

Regards,
Archontis

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Re: [Sursound] Ambisonics for Android and also Oculus..

[Politis Archontis]

The advantage of ACN is that it is a natural ordering of the HOA channels 
described with a single number q=n^2+n+m+1 (with n the order and m the degree), 
and it is aligned with pretty much any other field using spherical spectral 
analysis (graphics, signal processing, physics, etc...) , making transfer of 
knowledge from these fields to ambisonics much less confusing.

About ACN, if you are working on the more theoretical side of ambisonics, it is 
the only normalization that makes sense again since it keeps the spherical 
harmonics orthonormal and it simplifies most things on paper a lot! It can just 
as well be kept as a standard, however conversion to other normalizations (such 
as SN3D) are just a gain factor per order and very easy to do.

Regards,
Archontis





On 03 Apr 2016, at 10:51, Xavier Bonjour 
> wrote:

Hello,

And to add one more level of confusion, MPEG-H 3D Audio has gone for
ACN/N3D normalization!

Going beyond 3rd order  is also going for better quality and it makes
sense for the following reasons:

- Recording technologies make progress: we should expect multicapsules
microphone technology to improve and go beyond 3rd Order
- 3D sound can also be computer generated to any order and there is a
significant perceptual difference between the binaural rendering of 3rd
order content and content of higher orders. And this difference is even
bigger when HRTF are personalized
- Compression (MPEG-H 3D Audio,  ...)  will make HOA content manageable,
even on a smartphone.

I guess defining a normalization that covers HOA beyond 3rd order is about
getting the "format" ready for the future development.

Kind regards

-Xavier



-Original Message-
From: Sursound [mailto:sursound-boun...@music.vt.edu] On Behalf Of Albert
Leusink
Sent: dimanche 3 avril 2016 02:20
To: sursound@music.vt.edu
Subject: [Sursound] Ambisonics for Android and also Oculus..


Hello all,

Coming soon, to a phone near you !:

https://storage.googleapis.com/jump-inspector/Jump_Inspector_Quick_Start.p
df

There will definitely be many user complaints initially due to
misunderstandings as it uses ACN/SN3D ordering and 99% of all the tools
(VST plugins etc..) currently used by the VR community are FuMa / .AMB
based...

To add to that confusion, Oculus has just updated their Gear VR video
player specs to accept FuMa first order

I'm sure you have all had this discussion many times over, but what, if
any, are the advantages of 1st order ACN over FuMa?

>From what I've gathered, ACN was initially proposed as it would allow
bigger file sizes but I don't think that really applies to mobile phones
in this case...doesn't it only make sense to have ACN beyond 3rd order?



Have a good weekend,


Albert





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Re: [Sursound] Ambisonics for Android and also Oculus..

[Fons Adriaensen]

On Sun, Apr 03, 2016 at 12:20:05AM +, Albert Leusink wrote:

> I'm sure you have all had this discussion many times over, but what, if any,
> are the advantages of 1st order ACN over FuMa?

Consistency.

There are two aspects to this:

1. The naming scheme, which implicitly defines the order in which
   components, matrix elements, etc. are stored.
2. Normalisation.

ACN (for 1.) and N3D or SN3D (for 2.) both provide a simple and
unambiguous way to handle arbitrary higher order.

FuMa is inconsistent on both accounts. Which means that any
software or format that is supposed to handle arbitrary higher
orders has to include special cases in order to support the
FuMa subset. Doing that is almost always a bad idea.

Of course this leaves the question of how to handle 'legacy'
material. The simple answer is: convert it to an ACN/(S)N3D
format ASAP, put the original in the archives, and carry on. 

We do this all the time: when magnetic tapes are digitised,
the digital version doesn't retain the pre-emphasis, Dolby
noise reduction, etc. that were part of the original format.
Same for vinyl records or any other legacy storage formats,
including digital ones. Does anyone still create Amiga or
IRCAM sound files ?

Nobody questions this, so I really wonder why there is some
much resistance against dropping legacy AMB formats. 

Ciao,

-- 
FA

A world of exhaustive, reliable metadata would be an utopia.
It's also a pipe-dream, founded on self-delusion, nerd hubris
and hysterically inflated market opportunities. (Cory Doctorow)

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Re: [Sursound] Ambisonics for Android and also Oculus..

[Xavier Bonjour]

Hello,

And to add one more level of confusion, MPEG-H 3D Audio has gone for
ACN/N3D normalization!

Going beyond 3rd order  is also going for better quality and it makes
sense for the following reasons:

- Recording technologies make progress: we should expect multicapsules
microphone technology to improve and go beyond 3rd Order
- 3D sound can also be computer generated to any order and there is a
significant perceptual difference between the binaural rendering of 3rd
order content and content of higher orders. And this difference is even
bigger when HRTF are personalized
- Compression (MPEG-H 3D Audio,  ...)  will make HOA content manageable,
even on a smartphone.

I guess defining a normalization that covers HOA beyond 3rd order is about
getting the "format" ready for the future development.

Kind regards

-Xavier



-Original Message-
From: Sursound [mailto:sursound-boun...@music.vt.edu] On Behalf Of Albert
Leusink
Sent: dimanche 3 avril 2016 02:20
To: sursound@music.vt.edu
Subject: [Sursound] Ambisonics for Android and also Oculus..


Hello all,

Coming soon, to a phone near you !:

https://storage.googleapis.com/jump-inspector/Jump_Inspector_Quick_Start.p
df

There will definitely be many user complaints initially due to
misunderstandings as it uses ACN/SN3D ordering and 99% of all the tools
(VST plugins etc..) currently used by the VR community are FuMa / .AMB
based...

To add to that confusion, Oculus has just updated their Gear VR video
player specs to accept FuMa first order

I'm sure you have all had this discussion many times over, but what, if
any, are the advantages of 1st order ACN over FuMa?

>From what I've gathered, ACN was initially proposed as it would allow
bigger file sizes but I don't think that really applies to mobile phones
in this case...doesn't it only make sense to have ACN beyond 3rd order?



Have a good weekend,


Albert





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Re: [Sursound] Ambisonics for Android and also Oculus..

[Dave Malham]

Hi Albert,

Strictly speaking, FuMa is an extension of  MAG's original B Format
ordering for the Soundfield mic. and only ever went up to third order,
owing to the unfortunate fact that someone many centuries ago decided that
26 letters were enough to encode English. I have always referred to the
Soundfield type first order signal set (with the -3dB weighting on W) as "B
Format" and used "FuMa" only when working with signals that include higher
orders. However, I can see why it makes sense to refer to such first order
signals as FuMa also since it explicitly indicates that they include the
-3dB (and other weightings on the higher channels) to equalise maximise
levels in the channels.  This all made a lot of sense a couple of decades
ago when most of us were still using analogue tape machines and we had to
retain as much dynamic range as possible. Also having one, fixed, channel
ordering helped reduce the chance of errors*. Now, I no longer think that
this matters much with floating point coding eliminating dynamic range
limitations and the fact labelling can (or at least, should) be part of the
file itself.

   Dave Malham

*Labels do drop off tape reels and will always make strenuous efforts to do
so at the most inconvenient possible time. :-)


On 3 April 2016 at 01:20, Albert Leusink  wrote:

>
> Hello all,
>
> Coming soon, to a phone near you !:
>
>
> https://storage.googleapis.com/jump-inspector/Jump_Inspector_Quick_Start.pdf
>
> There will definitely be many user complaints initially due to
> misunderstandings as it uses ACN/SN3D ordering and 99% of all the tools
> (VST
> plugins etc..) currently used by the VR community are FuMa / .AMB based...
>
> To add to that confusion, Oculus has just updated their Gear VR video
> player
> specs to accept FuMa first order
>
> I'm sure you have all had this discussion many times over, but what, if
> any,
> are the advantages of 1st order ACN over FuMa?
>
> From what I've gathered, ACN was initially proposed as it would allow
> bigger
> file sizes but I don't think that really applies to mobile phones in this
> case...doesn't it only make sense to have ACN beyond 3rd order?
>
>
>
> Have a good weekend,
>
>
> Albert
>
>
>
>
>
> ___
> 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.
>



-- 

As of 1st October 2012, I have retired from the University.

These are my own views and may or may not be shared by the University

Dave Malham
Honorary Fellow, Department of Music
The University of York
York YO10 5DD
UK

'Ambisonics - Component Imaging for Audio'
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