Discussion:
A submittal for a patent on Ambisonics?
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Bearcat Şándor
2018-01-23 11:18:47 UTC
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I don't know a lot about patent law, but is this an attempt to tie up our
beloved Ambisonics?

http://www.freepatentsonline.com/y2017/0366912.html

If so, can we do anything about it?
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z***@gmail.com
2018-01-23 11:21:37 UTC
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Haven’t read it but as Ambisonics is public domain forever, as long as they don’t claim anything only related to Ambisonics it is fine

Sent from my iPhone

> On Jan 23, 2018, at 6:18 AM, Bearcat Şándor <***@gmail.com> wrote:
>
> I don't know a lot about patent law, but is this an attempt to tie up our
> beloved Ambisonics?
>
> http://www.freepatentsonline.com/y2017/0366912.html
>
> If so, can we do anything about it?
> -------------- next part --------------
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z***@gmail.com
2018-01-23 11:23:48 UTC
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I should say, as long as they don’t claim anything that’s previously been claimed.

Sent from my iPhone

> On Jan 23, 2018, at 6:18 AM, Bearcat Şándor <***@gmail.com> wrote:
>
> I don't know a lot about patent law, but is this an attempt to tie up our
> beloved Ambisonics?
>
> http://www.freepatentsonline.com/y2017/0366912.html
>
> If so, can we do anything about it?
> -------------- next part --------------
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Augustine Leudar
2018-01-23 11:33:55 UTC
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If he's trying to patents ambisonics and headtracking he has no chance,
howeve rif he has developed a new modification of ambisonics that lllows
soundsources to appear very close to the listener without just playing
around with reverb and frequency filtering (Ambisonics is not very good at
this currently) then that would be new and patentable.....

On 23 January 2018 at 11:23, <***@gmail.com> wrote:

> I should say, as long as they don’t claim anything that’s previously been
> claimed.
>
> Sent from my iPhone
>
> > On Jan 23, 2018, at 6:18 AM, Bearcat Şándor <***@gmail.com>
> wrote:
> >
> > I don't know a lot about patent law, but is this an attempt to tie up our
> > beloved Ambisonics?
> >
> > http://www.freepatentsonline.com/y2017/0366912.html
> >
> > If so, can we do anything about it?
> > -------------- next part --------------
> > An HTML attachment was scrubbed...
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> attachments/20180123/8502d237/attachment.html>
> > _______________________________________________
> > Sursound mailing list
> > ***@music.vt.edu
> > https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
> edit account or options, view archives and so on.
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> ***@music.vt.edu
> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
> edit account or options, view archives and so on.
>



--
Dr. Augustine Leudar
Artistic Director Magik Door LTD
Company Number : NI635217
Registered 63 Ballycoan rd,
Belfast BT88LL
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jack reynolds
2018-01-23 11:58:51 UTC
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It looks like a method for binaural rendering with multiple distance HRTFs.

Ambisonics could be one of the inputs, but it seems to be aimed more at
object based virtual reality, where the listener is more likely to come
very close to an audio source.

Most HRTFs are currently measured at 1m distance, so any objects closer
than 1m are not currently rendered correctly.

Far field HRTFs are closer to plane waves, whereas close up audio objects
emit more spherical waves, creating greater differences in interaural time
difference (ITD).

Jack

On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com> wrote:

> I don't know a lot about patent law, but is this an attempt to tie up our
> beloved Ambisonics?
>
> http://www.freepatentsonline.com/y2017/0366912.html
>
> If so, can we do anything about it?
> -------------- next part --------------
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> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
> edit account or options, view archives and so on.
>



--

07889727365

02036861372

3 Swimmers Lane
Haggerston
London
E2 8FR


www.facebook.com/reynoldsmicrophones

www.sohovr.co.uk
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Peter Lennox
2018-01-23 12:01:33 UTC
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...and interaural level differences for low frequencies


Dr. Peter Lennox SFHEA

Senior Lecturer in Perception

College of Arts, Humanities and Education

School of Arts



e: ***@derby.ac.uk<mailto:***@derby.ac.uk>

t: 01332 593155


https://derby.academia.edu/peterlennox
https://www.researchgate.net/profile/Peter_Lennox

University of Derby,
Kedleston Road,
Derby,
DE22 1GB, UK
________________________________
From: Sursound <sursound-***@music.vt.edu> on behalf of jack reynolds <***@gmail.com>
Sent: 23 January 2018 11:58:51
To: Surround Sound discussion group
Subject: Re: [Sursound] A submittal for a patent on Ambisonics?

It looks like a method for binaural rendering with multiple distance HRTFs.

Ambisonics could be one of the inputs, but it seems to be aimed more at
object based virtual reality, where the listener is more likely to come
very close to an audio source.

Most HRTFs are currently measured at 1m distance, so any objects closer
than 1m are not currently rendered correctly.

Far field HRTFs are closer to plane waves, whereas close up audio objects
emit more spherical waves, creating greater differences in interaural time
difference (ITD).

Jack

On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com> wrote:

> I don't know a lot about patent law, but is this an attempt to tie up our
> beloved Ambisonics?
>
> http://www.freepatentsonline.com/y2017/0366912.html
>
> If so, can we do anything about it?
> -------------- next part --------------
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> ***@music.vt.edu
> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
> edit account or options, view archives and so on.
>



--

07889727365

02036861372

3 Swimmers Lane
Haggerston
London
E2 8FR


www.facebook.com/reynoldsmicrophones<http://www.facebook.com/reynoldsmicrophones>

www.sohovr.co.uk<http://www.sohovr.co.uk>
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Augustine Leudar
2018-01-23 12:16:55 UTC
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Hi Jack,
Aside from ILDs, ITDs, I also wondered if the pinna was able to distinguish
very close sound sources due to the fact the wavefront would be much more
curved almost spherical to the degree that it would be different pressure
present at different folds of the pinna (ie very close up sound slike a
mosquito) . I dont think theres been much done on that...

On 23 January 2018 at 11:58, jack reynolds <***@gmail.com>
wrote:

> It looks like a method for binaural rendering with multiple distance HRTFs.
>
> Ambisonics could be one of the inputs, but it seems to be aimed more at
> object based virtual reality, where the listener is more likely to come
> very close to an audio source.
>
> Most HRTFs are currently measured at 1m distance, so any objects closer
> than 1m are not currently rendered correctly.
>
> Far field HRTFs are closer to plane waves, whereas close up audio objects
> emit more spherical waves, creating greater differences in interaural time
> difference (ITD).
>
> Jack
>
> On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com>
> wrote:
>
> > I don't know a lot about patent law, but is this an attempt to tie up our
> > beloved Ambisonics?
> >
> > http://www.freepatentsonline.com/y2017/0366912.html
> >
> > If so, can we do anything about it?
> > -------------- next part --------------
> > An HTML attachment was scrubbed...
> > URL: <https://mail.music.vt.edu/mailman/private/sursound/
> > attachments/20180123/8502d237/attachment.html>
> > _______________________________________________
> > Sursound mailing list
> > ***@music.vt.edu
> > https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
> > edit account or options, view archives and so on.
> >
>
>
>
> --
>
> 07889727365
>
> 02036861372
>
> 3 Swimmers Lane
> Haggerston
> London
> E2 8FR
>
>
> www.facebook.com/reynoldsmicrophones
>
> www.sohovr.co.uk
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>



--
Dr. Augustine Leudar
Artistic Director Magik Door LTD
Company Number : NI635217
Registered 63 Ballycoan rd,
Belfast BT88LL
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Jack Reynolds
2018-01-23 13:54:30 UTC
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I’m sure that the pinna must have an affect at close range.
I’m really looking forward to multiple distance HRTFs become a reality, as this is one of the limitations currently.
Similarly, mulitiple A to B microphone filters, measured at different distances would be nice!

Sent from my iPhone

> On 23 Jan 2018, at 12:16, Augustine Leudar <***@gmail.com> wrote:
>
> Hi Jack,
> Aside from ILDs, ITDs, I also wondered if the pinna was able to distinguish
> very close sound sources due to the fact the wavefront would be much more
> curved almost spherical to the degree that it would be different pressure
> present at different folds of the pinna (ie very close up sound slike a
> mosquito) . I dont think theres been much done on that...
>
> On 23 January 2018 at 11:58, jack reynolds <***@gmail.com>
> wrote:
>
>> It looks like a method for binaural rendering with multiple distance HRTFs.
>>
>> Ambisonics could be one of the inputs, but it seems to be aimed more at
>> object based virtual reality, where the listener is more likely to come
>> very close to an audio source.
>>
>> Most HRTFs are currently measured at 1m distance, so any objects closer
>> than 1m are not currently rendered correctly.
>>
>> Far field HRTFs are closer to plane waves, whereas close up audio objects
>> emit more spherical waves, creating greater differences in interaural time
>> difference (ITD).
>>
>> Jack
>>
>> On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com>
>> wrote:
>>
>>> I don't know a lot about patent law, but is this an attempt to tie up our
>>> beloved Ambisonics?
>>>
>>> http://www.freepatentsonline.com/y2017/0366912.html
>>>
>>> If so, can we do anything about it?
>>> -------------- next part --------------
>>> An HTML attachment was scrubbed...
>>> URL: <https://mail.music.vt.edu/mailman/private/sursound/
>>> attachments/20180123/8502d237/attachment.html>
>>> _______________________________________________
>>> Sursound mailing list
>>> ***@music.vt.edu
>>> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
>>> edit account or options, view archives and so on.
>>>
>>
>>
>>
>> --
>>
>> 07889727365
>>
>> 02036861372
>>
>> 3 Swimmers Lane
>> Haggerston
>> London
>> E2 8FR
>>
>>
>> www.facebook.com/reynoldsmicrophones
>>
>> www.sohovr.co.uk
>> -------------- next part --------------
>> An HTML attachment was scrubbed...
>> URL: <https://mail.music.vt.edu/mailman/private/sursound/
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>> _______________________________________________
>> Sursound mailing list
>> ***@music.vt.edu
>> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
>> edit account or options, view archives and so on.
>>
>
>
>
> --
> Dr. Augustine Leudar
> Artistic Director Magik Door LTD
> Company Number : NI635217
> Registered 63 Ballycoan rd,
> Belfast BT88LL
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Antti Vanne
2018-01-23 15:20:30 UTC
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If someone is interested digging deeper into near field HRTFs, there's one
high resolution HRTF available at http://idaaudio.com/downloads/

Sofa format allows storing impulse responses at multiple distances and Spat
Revolution should be able to use that for rendering point sources.

On Tue, Jan 23, 2018 at 3:54 PM, Jack Reynolds <***@gmail.com>
wrote:

> I’m sure that the pinna must have an affect at close range.
> I’m really looking forward to multiple distance HRTFs become a reality, as
> this is one of the limitations currently.
> Similarly, mulitiple A to B microphone filters, measured at different
> distances would be nice!
>
> Sent from my iPhone
>
> > On 23 Jan 2018, at 12:16, Augustine Leudar <***@gmail.com>
> wrote:
> >
> > Hi Jack,
> > Aside from ILDs, ITDs, I also wondered if the pinna was able to
> distinguish
> > very close sound sources due to the fact the wavefront would be much more
> > curved almost spherical to the degree that it would be different pressure
> > present at different folds of the pinna (ie very close up sound slike a
> > mosquito) . I dont think theres been much done on that...
> >
> > On 23 January 2018 at 11:58, jack reynolds <***@gmail.com>
> > wrote:
> >
> >> It looks like a method for binaural rendering with multiple distance
> HRTFs.
> >>
> >> Ambisonics could be one of the inputs, but it seems to be aimed more at
> >> object based virtual reality, where the listener is more likely to come
> >> very close to an audio source.
> >>
> >> Most HRTFs are currently measured at 1m distance, so any objects closer
> >> than 1m are not currently rendered correctly.
> >>
> >> Far field HRTFs are closer to plane waves, whereas close up audio
> objects
> >> emit more spherical waves, creating greater differences in interaural
> time
> >> difference (ITD).
> >>
> >> Jack
> >>
> >> On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com>
> >> wrote:
> >>
> >>> I don't know a lot about patent law, but is this an attempt to tie up
> our
> >>> beloved Ambisonics?
> >>>
> >>> http://www.freepatentsonline.com/y2017/0366912.html
> >>>
> >>> If so, can we do anything about it?
> >>> -------------- next part --------------
> >>> An HTML attachment was scrubbed...
> >>> URL: <https://mail.music.vt.edu/mailman/private/sursound/
> >>> attachments/20180123/8502d237/attachment.html>
> >>> _______________________________________________
> >>> Sursound mailing list
> >>> ***@music.vt.edu
> >>> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe
> here,
> >>> edit account or options, view archives and so on.
> >>>
> >>
> >>
> >>
> >> --
> >>
> >> 07889727365
> >>
> >> 02036861372
> >>
> >> 3 Swimmers Lane
> >> Haggerston
> >> London
> >> E2 8FR
> >>
> >>
> >> www.facebook.com/reynoldsmicrophones
> >>
> >> www.sohovr.co.uk
> >> -------------- next part --------------
> >> An HTML attachment was scrubbed...
> >> URL: <https://mail.music.vt.edu/mailman/private/sursound/
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> >> _______________________________________________
> >> Sursound mailing list
> >> ***@music.vt.edu
> >> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
> >> edit account or options, view archives and so on.
> >>
> >
> >
> >
> > --
> > Dr. Augustine Leudar
> > Artistic Director Magik Door LTD
> > Company Number : NI635217
> > Registered 63 Ballycoan rd,
> > Belfast BT88LL
> > -------------- next part --------------
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> > ***@music.vt.edu
> > https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
> edit account or options, view archives and so on.
> _______________________________________________
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> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
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>



--
Antti Vanne
OwnSurround Ltd / IDA Audio
CEO

Haapaniemenkatu 40
<https://maps.google.com/?q=Haapaniemenkatu+40&entry=gmail&source=g> E 1
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s***@mail.telepac.pt
2018-01-24 02:12:16 UTC
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Citando Augustine Leudar <***@gmail.com>:

> Hi Jack,
>
> Aside from ILDs, ITDs, I also wondered if the pinna was able to distinguish
>
> very close sound sources due to the fact the wavefront would be much more
>
> curved almost spherical to the degree that it would be different pressure
>
> present at different folds of the pinna (ie  very close up  sound slike a
>
> mosquito) . I dont think theres been much done on that...

Hi Augustine,

I think "there has been done quite a lot on that"... 😉

(Reproduction of near-field audio sources)

Beside of spherical waves (and their consequences) we should not
overlook that any high-frequency emitting (annoying) mosquito next to
your left ear would be heard much softer at your right ear, the head
shadow being even more relevant at close distances.

BR

Stefan

P.S.: It is important to know about the "depth" of a mosquito audio
object relative to your head, both in VR and in real life...

> On 23 January 2018 at 11:58, jack reynolds <***@gmail.com>
>
> wrote:
>
>> It looks like a method for binaural rendering with multiple distance HRTFs.
>>
>>
>>
>> Ambisonics could be one of the inputs, but it seems to be aimed more at
>>
>> object based virtual reality, where the listener is more likely to come
>>
>> very close to an audio source.
>>
>>
>>
>> Most HRTFs are currently measured at 1m distance, so any objects closer
>>
>> than 1m are not currently rendered correctly.
>>
>>
>>
>> Far field HRTFs are closer to plane waves, whereas close up audio objects
>>
>> emit more spherical waves, creating greater differences in interaural time
>>
>> difference (ITD).
>>
>>
>>
>> Jack
>>
>>
>>
>> On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com>
>>
>> wrote:
>>
>>
>>
>> I don't know a lot about patent law, but is this an attempt to tie up our
>>
>> beloved Ambisonics?
>>
>>
>>
>> http://www.freepatentsonline.com/y2017/0366912.html
>>
>>
>>
>> ....
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Augustine Leudar
2018-01-24 02:45:11 UTC
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Hi Stefan -
Im aware of the role of ILDs and ITDs at close distances - but I couldnt
find any papers on the curvature being a cue at very close distances though
- be interested to read some - have you got any links ?

On 24 January 2018 at 02:12, <***@mail.telepac.pt> wrote:

> Citando Augustine Leudar <***@gmail.com>:
>
> Hi Jack,
>>
>> Aside from ILDs, ITDs, I also wondered if the pinna was able to
>> distinguish
>>
>> very close sound sources due to the fact the wavefront would be much more
>>
>> curved almost spherical to the degree that it would be different pressure
>>
>> present at different folds of the pinna (ie very close up sound slike a
>>
>> mosquito) . I dont think theres been much done on that...
>>
>
> Hi Augustine,
>
> I think "there has been done quite a lot on that"... 😉
>
> (Reproduction of near-field audio sources)
>
> Beside of spherical waves (and their consequences) we should not overlook
> that any high-frequency emitting (annoying) mosquito next to your left ear
> would be heard much softer at your right ear, the head shadow being even
> more relevant at close distances.
>
> BR
>
> Stefan
>
> P.S.: It is important to know about the "depth" of a mosquito audio object
> relative to your head, both in VR and in real life...
>
> On 23 January 2018 at 11:58, jack reynolds <***@gmail.com>
>>
>> wrote:
>>
>> It looks like a method for binaural rendering with multiple distance
>>> HRTFs.
>>>
>>>
>>>
>>> Ambisonics could be one of the inputs, but it seems to be aimed more at
>>>
>>> object based virtual reality, where the listener is more likely to come
>>>
>>> very close to an audio source.
>>>
>>>
>>>
>>> Most HRTFs are currently measured at 1m distance, so any objects closer
>>>
>>> than 1m are not currently rendered correctly.
>>>
>>>
>>>
>>> Far field HRTFs are closer to plane waves, whereas close up audio
>>> objects
>>>
>>> emit more spherical waves, creating greater differences in interaural
>>> time
>>>
>>> difference (ITD).
>>>
>>>
>>>
>>> Jack
>>>
>>>
>>>
>>> On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com>
>>>
>>> wrote:
>>>
>>>
>>>
>>> I don't know a lot about patent law, but is this an attempt to tie up
>>> our
>>>
>>> beloved Ambisonics?
>>>
>>>
>>>
>>> http://www.freepatentsonline.com/y2017/0366912.html
>>>
>>>
>>>
>>> ....
>>>
>> -------------- next part --------------
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> ***@music.vt.edu
> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
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>



--
Dr. Augustine Leudar
Artistic Director Magik Door LTD
Company Number : NI635217
Registered 63 Ballycoan rd,
Belfast BT88LL
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Augustine Leudar
2018-01-24 02:47:12 UTC
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Curvature could give you info on the size of the object as well .....

On 24 January 2018 at 02:45, Augustine Leudar <***@gmail.com>
wrote:

> Hi Stefan -
> Im aware of the role of ILDs and ITDs at close distances - but I couldnt
> find any papers on the curvature being a cue at very close distances though
> - be interested to read some - have you got any links ?
>
> On 24 January 2018 at 02:12, <***@mail.telepac.pt> wrote:
>
>> Citando Augustine Leudar <***@gmail.com>:
>>
>> Hi Jack,
>>>
>>> Aside from ILDs, ITDs, I also wondered if the pinna was able to
>>> distinguish
>>>
>>> very close sound sources due to the fact the wavefront would be much
>>> more
>>>
>>> curved almost spherical to the degree that it would be different
>>> pressure
>>>
>>> present at different folds of the pinna (ie very close up sound slike
>>> a
>>>
>>> mosquito) . I dont think theres been much done on that...
>>>
>>
>> Hi Augustine,
>>
>> I think "there has been done quite a lot on that"... 😉
>>
>> (Reproduction of near-field audio sources)
>>
>> Beside of spherical waves (and their consequences) we should not overlook
>> that any high-frequency emitting (annoying) mosquito next to your left ear
>> would be heard much softer at your right ear, the head shadow being even
>> more relevant at close distances.
>>
>> BR
>>
>> Stefan
>>
>> P.S.: It is important to know about the "depth" of a mosquito audio
>> object relative to your head, both in VR and in real life...
>>
>> On 23 January 2018 at 11:58, jack reynolds <***@gmail.com>
>>>
>>> wrote:
>>>
>>> It looks like a method for binaural rendering with multiple distance
>>>> HRTFs.
>>>>
>>>>
>>>>
>>>> Ambisonics could be one of the inputs, but it seems to be aimed more at
>>>>
>>>> object based virtual reality, where the listener is more likely to come
>>>>
>>>> very close to an audio source.
>>>>
>>>>
>>>>
>>>> Most HRTFs are currently measured at 1m distance, so any objects closer
>>>>
>>>> than 1m are not currently rendered correctly.
>>>>
>>>>
>>>>
>>>> Far field HRTFs are closer to plane waves, whereas close up audio
>>>> objects
>>>>
>>>> emit more spherical waves, creating greater differences in interaural
>>>> time
>>>>
>>>> difference (ITD).
>>>>
>>>>
>>>>
>>>> Jack
>>>>
>>>>
>>>>
>>>> On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com>
>>>>
>>>> wrote:
>>>>
>>>>
>>>>
>>>> I don't know a lot about patent law, but is this an attempt to tie up
>>>> our
>>>>
>>>> beloved Ambisonics?
>>>>
>>>>
>>>>
>>>> http://www.freepatentsonline.com/y2017/0366912.html
>>>>
>>>>
>>>>
>>>> ....
>>>>
>>> -------------- next part --------------
>> An HTML attachment was scrubbed...
>> URL: <https://mail.music.vt.edu/mailman/private/sursound/attachme
>> nts/20180124/16ff3135/attachment.html>
>>
>> _______________________________________________
>> Sursound mailing list
>> ***@music.vt.edu
>> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
>> edit account or options, view archives and so on.
>>
>
>
>
> --
> Dr. Augustine Leudar
> Artistic Director Magik Door LTD
> Company Number : NI635217
> Registered 63 Ballycoan rd,
> Belfast BT88LL
>
>


--
Dr. Augustine Leudar
Artistic Director Magik Door LTD
Company Number : NI635217
Registered 63 Ballycoan rd,
Belfast BT88LL
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John Merchant
2018-01-24 14:01:21 UTC
Reply
Permalink
Raw Message
Tom Smurdon and Peter Stirling of Oculus presented research on near-field HRTF for VR at last fall's OC4. The video of that talk is available here:
https://www.youtube.com/watch?v=l7mhXRB9PA4

________________________________________
From: Sursound <sursound-***@music.vt.edu> on behalf of ***@mail.telepac.pt <***@mail.telepac.pt>
Sent: Tuesday, January 23, 2018 8:12 PM
To: Surround Sound discussion group
Subject: Re: [Sursound] A submittal for a patent on Ambisonics?

Citando Augustine Leudar <***@gmail.com>:

> Hi Jack,
>
> Aside from ILDs, ITDs, I also wondered if the pinna was able to distinguish
>
> very close sound sources due to the fact the wavefront would be much more
>
> curved almost spherical to the degree that it would be different pressure
>
> present at different folds of the pinna (ie very close up sound slike a
>
> mosquito) . I dont think theres been much done on that...

Hi Augustine,

I think "there has been done quite a lot on that"... 😉

(Reproduction of near-field audio sources)

Beside of spherical waves (and their consequences) we should not
overlook that any high-frequency emitting (annoying) mosquito next to
your left ear would be heard much softer at your right ear, the head
shadow being even more relevant at close distances.

BR

Stefan

P.S.: It is important to know about the "depth" of a mosquito audio
object relative to your head, both in VR and in real life...

> On 23 January 2018 at 11:58, jack reynolds <***@gmail.com>
>
> wrote:
>
>> It looks like a method for binaural rendering with multiple distance HRTFs.
>>
>>
>>
>> Ambisonics could be one of the inputs, but it seems to be aimed more at
>>
>> object based virtual reality, where the listener is more likely to come
>>
>> very close to an audio source.
>>
>>
>>
>> Most HRTFs are currently measured at 1m distance, so any objects closer
>>
>> than 1m are not currently rendered correctly.
>>
>>
>>
>> Far field HRTFs are closer to plane waves, whereas close up audio objects
>>
>> emit more spherical waves, creating greater differences in interaural time
>>
>> difference (ITD).
>>
>>
>>
>> Jack
>>
>>
>>
>> On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com>
>>
>> wrote:
>>
>>
>>
>> I don't know a lot about patent law, but is this an attempt to tie up our
>>
>> beloved Ambisonics?
>>
>>
>>
>> http://www.freepatentsonline.com/y2017/0366912.html
>>
>>
>>
>> ....
-------------- next part --------------
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Markus Noisternig (IRCAM)
2018-01-24 14:35:43 UTC
Reply
Permalink
Raw Message
Dear All,

Here are some references:

Brungart and Rabinowitz [1] showed that HRTF vary significantly for sources in the proximity region (i.e. at distances less than 1m from the head).
Lentz et al. [2] perceptually evaluated measured HRTFs at different distances from the head, showing limits of noticeable differences between near-field and far-field HRTFs.
Romblom and Cook [3] proposed near-field compensation filters.
Duraiswami et al. [4], Zhang et al. [5], and Pollow et al. [6] compute HRTFs for arbitrary field points using spherical harmonics decomposition (as an extension of the work of Evans et al. [7]).
Duda and Martens [8] evaluated simulation results on a spherical head model

Have fun reading!

Very best,

Markus

[1] D.S.Brungart,W.M.Rabinowitz:Auditorylocalizationof nearby sources. head-related transfer functions. J. Acoust. Soc. Am. 106 (1999) 1465–1479.
[2] T. Lentz, I. Assenmacher, M. Vorländer, T. Kuhlen: Precise near-to-head acoustics with binaural synthesis. Journal of Virtual Reality and Broadcasting 3 (2006).
[3] D. Romblom, B. Cook: Near-field compensation for hrtf processing. 125th Conv. Audio Eng. Soc., San Francisco, USA, 2008, no. 7611.
[4 ]R. Duraiswami, D. N. Zotkin, N. A. Gumerov: Interpola- tion and range extrapolation of HRTFs. IEEE ICASSP, Montreal, Canada, 2004, 45–48.
[5] W. Zhang, T. D. Abhayapala, R. A. Kennedy, R. Du- raiswami: Modal expansion of HRTFs: Continuous repre- sentation in frequency-range-angle. ICASSP, Los Alami- tos, USA: IEEE Computer Society, 2009, 285–288.
[6] Pollow, M., Nguyen, K.-V., Warusfel, O., Carpentier, T., Müller-Trapet, M., Vorländer, M., and Noisternig, M. (2012). “Calculation of Head-Related Transfer Functions for Arbitrary Field Points Using Spherical Harmonics Decomposition,” Acta Acust United Ac, 98, 72–82. doi:10.3813/AAA.918493
[7] M. J. Evans, J. A. S. Angus, A. I. Tew: Analyzing head- related transfer function measurements using surface spher- ical harmonics. J. Acoust. Soc. Am. 104 (1998) 2400– 2411
[8] R. O. Duda, W. L. Martens: Range dependence of the re- sponse of a spherical head model. J. Acoust. Soc. Am. 104 (1998) 3048–3058.


> On 24 Jan 2018, at 15:01, John Merchant <***@mtsu.edu> wrote:
>
> Tom Smurdon and Peter Stirling of Oculus presented research on near-field HRTF for VR at last fall's OC4. The video of that talk is available here:
> https://www.youtube.com/watch?v=l7mhXRB9PA4
>
> ________________________________________
> From: Sursound <sursound-***@music.vt.edu> on behalf of ***@mail.telepac.pt <***@mail.telepac.pt>
> Sent: Tuesday, January 23, 2018 8:12 PM
> To: Surround Sound discussion group
> Subject: Re: [Sursound] A submittal for a patent on Ambisonics?
>
> Citando Augustine Leudar <***@gmail.com>:
>
>> Hi Jack,
>>
>> Aside from ILDs, ITDs, I also wondered if the pinna was able to distinguish
>>
>> very close sound sources due to the fact the wavefront would be much more
>>
>> curved almost spherical to the degree that it would be different pressure
>>
>> present at different folds of the pinna (ie very close up sound slike a
>>
>> mosquito) . I dont think theres been much done on that...
>
> Hi Augustine,
>
> I think "there has been done quite a lot on that"... 😉
>
> (Reproduction of near-field audio sources)
>
> Beside of spherical waves (and their consequences) we should not
> overlook that any high-frequency emitting (annoying) mosquito next to
> your left ear would be heard much softer at your right ear, the head
> shadow being even more relevant at close distances.
>
> BR
>
> Stefan
>
> P.S.: It is important to know about the "depth" of a mosquito audio
> object relative to your head, both in VR and in real life...
>
>> On 23 January 2018 at 11:58, jack reynolds <***@gmail.com>
>>
>> wrote:
>>
>>> It looks like a method for binaural rendering with multiple distance HRTFs.
>>>
>>>
>>>
>>> Ambisonics could be one of the inputs, but it seems to be aimed more at
>>>
>>> object based virtual reality, where the listener is more likely to come
>>>
>>> very close to an audio source.
>>>
>>>
>>>
>>> Most HRTFs are currently measured at 1m distance, so any objects closer
>>>
>>> than 1m are not currently rendered correctly.
>>>
>>>
>>>
>>> Far field HRTFs are closer to plane waves, whereas close up audio objects
>>>
>>> emit more spherical waves, creating greater differences in interaural time
>>>
>>> difference (ITD).
>>>
>>>
>>>
>>> Jack
>>>
>>>
>>>
>>> On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com>
>>>
>>> wrote:
>>>
>>>
>>>
>>> I don't know a lot about patent law, but is this an attempt to tie up our
>>>
>>> beloved Ambisonics?
>>>
>>>
>>>
>>> http://www.freepatentsonline.com/y2017/0366912.html
>>>
>>>
>>>
>>> ....
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20180124/16ff3135/attachment.html>
> _______________________________________________
> Sursound mailing list
> ***@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
> ***@music.vt.edu
> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit account or options, view archives and so on.
s***@mail.telepac.pt
2018-01-24 15:22:01 UTC
Reply
Permalink
Raw Message
Hello Markus,

many thanks for providing the literature list.

I am very busy just now, and simply don't have enough time to do some
"recherche" for the sursound list...

(Including doing some patent recherche, which will be up to the USPTO later. )


Best regards


Stefan (Schreiber)








Citando Markus Noisternig (IRCAM) <***@ircam.fr>:

> Dear All,
>
> Here are some references:
>
> Brungart and Rabinowitz [1] showed that HRTF vary significantly for
> sources in the proximity region (i.e. at distances less than 1m from
> the head).
> Lentz et al. [2] perceptually evaluated measured HRTFs at different
> distances from the head, showing limits of noticeable differences
> between near-field and far-field HRTFs.
> Romblom and Cook [3] proposed near-field compensation filters.
> Duraiswami et al. [4], Zhang et al. [5], and Pollow et al. [6]
> compute HRTFs for arbitrary field points using spherical harmonics
> decomposition (as an extension of the work of Evans et al. [7]).
> Duda and Martens [8] evaluated simulation results on a spherical head model
>
> Have fun reading!
>
> Very best,
>
> Markus
>
> [1] D.S.Brungart,W.M.Rabinowitz:Auditorylocalizationof nearby
> sources. head-related transfer functions. J. Acoust. Soc. Am. 106
> (1999) 1465–1479.
> [2] T. Lentz, I. Assenmacher, M. Vorländer, T. Kuhlen: Precise
> near-to-head acoustics with binaural synthesis. Journal of Virtual
> Reality and Broadcasting 3 (2006).
> [3] D. Romblom, B. Cook: Near-field compensation for hrtf
> processing. 125th Conv. Audio Eng. Soc., San Francisco, USA, 2008,
> no. 7611.
> [4 ]R. Duraiswami, D. N. Zotkin, N. A. Gumerov: Interpola- tion and
> range extrapolation of HRTFs. IEEE ICASSP, Montreal, Canada, 2004,
> 45–48.
> [5] W. Zhang, T. D. Abhayapala, R. A. Kennedy, R. Du- raiswami:
> Modal expansion of HRTFs: Continuous repre- sentation in
> frequency-range-angle. ICASSP, Los Alami- tos, USA: IEEE Computer
> Society, 2009, 285–288.
> [6] Pollow, M., Nguyen, K.-V., Warusfel, O., Carpentier, T.,
> Müller-Trapet, M., Vorländer, M., and Noisternig, M. (2012).
> “Calculation of Head-Related Transfer Functions for Arbitrary Field
> Points Using Spherical Harmonics Decomposition,” Acta Acust United
> Ac, 98, 72–82. doi:10.3813/AAA.918493
> [7] M. J. Evans, J. A. S. Angus, A. I. Tew: Analyzing head- related
> transfer function measurements using surface spher- ical harmonics.
> J. Acoust. Soc. Am. 104 (1998) 2400– 2411
> [8] R. O. Duda, W. L. Martens: Range dependence of the re- sponse of
> a spherical head model. J. Acoust. Soc. Am. 104 (1998) 3048–3058.
>
>
>> On 24 Jan 2018, at 15:01, John Merchant <***@mtsu.edu> wrote:
>>
>> Tom Smurdon and Peter Stirling of Oculus presented research on
>> near-field HRTF for VR at last fall's OC4. The video of that talk
>> is available here:
>> https://www.youtube.com/watch?v=l7mhXRB9PA4
>>
>> ________________________________________
>> From: Sursound <sursound-***@music.vt.edu> on behalf of
>> ***@mail.telepac.pt <***@mail.telepac.pt>
>> Sent: Tuesday, January 23, 2018 8:12 PM
>> To: Surround Sound discussion group
>> Subject: Re: [Sursound] A submittal for a patent on Ambisonics?
>>
>> Citando Augustine Leudar <***@gmail.com>:
>>
>>> Hi Jack,
>>>
>>> Aside from ILDs, ITDs, I also wondered if the pinna was able to distinguish
>>>
>>> very close sound sources due to the fact the wavefront would be much more
>>>
>>> curved almost spherical to the degree that it would be different pressure
>>>
>>> present at different folds of the pinna (ie very close up sound slike a
>>>
>>> mosquito) . I dont think theres been much done on that...
>>
>> Hi Augustine,
>>
>> I think "there has been done quite a lot on that"... 😉
>>
>> (Reproduction of near-field audio sources)
>>
>> Beside of spherical waves (and their consequences) we should not
>> overlook that any high-frequency emitting (annoying) mosquito next to
>> your left ear would be heard much softer at your right ear, the head
>> shadow being even more relevant at close distances.
>>
>> BR
>>
>> Stefan
>>
>> P.S.: It is important to know about the "depth" of a mosquito audio
>> object relative to your head, both in VR and in real life...
>>
>>> On 23 January 2018 at 11:58, jack reynolds <***@gmail.com>
>>>
>>> wrote:
>>>
>>>> It looks like a method for binaural rendering with multiple
>>>> distance HRTFs.
>>>>
>>>>
>>>>
>>>> Ambisonics could be one of the inputs, but it seems to be aimed more at
>>>>
>>>> object based virtual reality, where the listener is more likely to come
>>>>
>>>> very close to an audio source.
>>>>
>>>>
>>>>
>>>> Most HRTFs are currently measured at 1m distance, so any objects closer
>>>>
>>>> than 1m are not currently rendered correctly.
>>>>
>>>>
>>>>
>>>> Far field HRTFs are closer to plane waves, whereas close up audio objects
>>>>
>>>> emit more spherical waves, creating greater differences in interaural time
>>>>
>>>> difference (ITD).
>>>>
>>>>
>>>>
>>>> Jack
>>>>
>>>>
>>>>
>>>> On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com>
>>>>
>>>> wrote:
>>>>
>>>>
>>>>
>>>> I don't know a lot about patent law, but is this an attempt to tie up our
>>>>
>>>> beloved Ambisonics?
>>>>
>>>>
>>>>
>>>> http://www.freepatentsonline.com/y2017/0366912.html
>>>>
>>>>
>>>>
>>>> ....
>> -------------- next part --------------
>> An HTML attachment was scrubbed...
>> URL:
>> <https://mail.music.vt.edu/mailman/private/sursound/attachments/20180124/16ff3135/attachment.html>
>> _______________________________________________
>> Sursound mailing list
>> ***@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
>> ***@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
> ***@music.vt.edu
> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe
> here, edit account or options, view archives and so on.
Augustine Leudar
2018-01-29 10:41:51 UTC
Reply
Permalink
Raw Message
Thanks for the list Markus,
I read the conclusions and abstracts for these papers and skimmed through
them - I am also quite busy ! However none of them seem to investigate or
suggest that the curvature of the wavefront and this curvatures interaction
with pinna folds is a potential distance and size cue in the nearfiled. I
did find this though which mentions it but doesnt really investigate (or
reference a source unfortunately) :

https://pdfs.semanticscholar.org/0664/8964b53ac8f812b0068088caa4838c3ba7ce.pdf

On 24 January 2018 at 14:35, Markus Noisternig (IRCAM) <
***@ircam.fr> wrote:

> Dear All,
>
> Here are some references:
>
> Brungart and Rabinowitz [1] showed that HRTF vary significantly for
> sources in the proximity region (i.e. at distances less than 1m from the
> head).
> Lentz et al. [2] perceptually evaluated measured HRTFs at different
> distances from the head, showing limits of noticeable differences between
> near-field and far-field HRTFs.
> Romblom and Cook [3] proposed near-field compensation filters.
> Duraiswami et al. [4], Zhang et al. [5], and Pollow et al. [6] compute
> HRTFs for arbitrary field points using spherical harmonics decomposition
> (as an extension of the work of Evans et al. [7]).
> Duda and Martens [8] evaluated simulation results on a spherical head model
>
> Have fun reading!
>
> Very best,
>
> Markus
>
> [1] D.S.Brungart,W.M.Rabinowitz:Auditorylocalizationof nearby sources.
> head-related transfer functions. J. Acoust. Soc. Am. 106 (1999) 1465–1479.
> [2] T. Lentz, I. Assenmacher, M. Vorländer, T. Kuhlen: Precise
> near-to-head acoustics with binaural synthesis. Journal of Virtual Reality
> and Broadcasting 3 (2006).
> [3] D. Romblom, B. Cook: Near-field compensation for hrtf processing.
> 125th Conv. Audio Eng. Soc., San Francisco, USA, 2008, no. 7611.
> [4 ]R. Duraiswami, D. N. Zotkin, N. A. Gumerov: Interpola- tion and range
> extrapolation of HRTFs. IEEE ICASSP, Montreal, Canada, 2004, 45–48.
> [5] W. Zhang, T. D. Abhayapala, R. A. Kennedy, R. Du- raiswami: Modal
> expansion of HRTFs: Continuous repre- sentation in frequency-range-angle.
> ICASSP, Los Alami- tos, USA: IEEE Computer Society, 2009, 285–288.
> [6] Pollow, M., Nguyen, K.-V., Warusfel, O., Carpentier, T.,
> Müller-Trapet, M., Vorländer, M., and Noisternig, M. (2012). “Calculation
> of Head-Related Transfer Functions for Arbitrary Field Points Using
> Spherical Harmonics Decomposition,” Acta Acust United Ac, 98, 72–82.
> doi:10.3813/AAA.918493
> [7] M. J. Evans, J. A. S. Angus, A. I. Tew: Analyzing head- related
> transfer function measurements using surface spher- ical harmonics. J.
> Acoust. Soc. Am. 104 (1998) 2400– 2411
> [8] R. O. Duda, W. L. Martens: Range dependence of the re- sponse of a
> spherical head model. J. Acoust. Soc. Am. 104 (1998) 3048–3058.
>
>
> > On 24 Jan 2018, at 15:01, John Merchant <***@mtsu.edu> wrote:
> >
> > Tom Smurdon and Peter Stirling of Oculus presented research on
> near-field HRTF for VR at last fall's OC4. The video of that talk is
> available here:
> > https://www.youtube.com/watch?v=l7mhXRB9PA4
> >
> > ________________________________________
> > From: Sursound <sursound-***@music.vt.edu> on behalf of
> ***@mail.telepac.pt <***@mail.telepac.pt>
> > Sent: Tuesday, January 23, 2018 8:12 PM
> > To: Surround Sound discussion group
> > Subject: Re: [Sursound] A submittal for a patent on Ambisonics?
> >
> > Citando Augustine Leudar <***@gmail.com>:
> >
> >> Hi Jack,
> >>
> >> Aside from ILDs, ITDs, I also wondered if the pinna was able to
> distinguish
> >>
> >> very close sound sources due to the fact the wavefront would be much
> more
> >>
> >> curved almost spherical to the degree that it would be different
> pressure
> >>
> >> present at different folds of the pinna (ie very close up sound slike
> a
> >>
> >> mosquito) . I dont think theres been much done on that...
> >
> > Hi Augustine,
> >
> > I think "there has been done quite a lot on that"... 😉
> >
> > (Reproduction of near-field audio sources)
> >
> > Beside of spherical waves (and their consequences) we should not
> > overlook that any high-frequency emitting (annoying) mosquito next to
> > your left ear would be heard much softer at your right ear, the head
> > shadow being even more relevant at close distances.
> >
> > BR
> >
> > Stefan
> >
> > P.S.: It is important to know about the "depth" of a mosquito audio
> > object relative to your head, both in VR and in real life...
> >
> >> On 23 January 2018 at 11:58, jack reynolds <***@gmail.com>
> >>
> >> wrote:
> >>
> >>> It looks like a method for binaural rendering with multiple distance
> HRTFs.
> >>>
> >>>
> >>>
> >>> Ambisonics could be one of the inputs, but it seems to be aimed more at
> >>>
> >>> object based virtual reality, where the listener is more likely to come
> >>>
> >>> very close to an audio source.
> >>>
> >>>
> >>>
> >>> Most HRTFs are currently measured at 1m distance, so any objects closer
> >>>
> >>> than 1m are not currently rendered correctly.
> >>>
> >>>
> >>>
> >>> Far field HRTFs are closer to plane waves, whereas close up audio
> objects
> >>>
> >>> emit more spherical waves, creating greater differences in interaural
> time
> >>>
> >>> difference (ITD).
> >>>
> >>>
> >>>
> >>> Jack
> >>>
> >>>
> >>>
> >>> On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com>
> >>>
> >>> wrote:
> >>>
> >>>
> >>>
> >>> I don't know a lot about patent law, but is this an attempt to tie up
> our
> >>>
> >>> beloved Ambisonics?
> >>>
> >>>
> >>>
> >>> http://www.freepatentsonline.com/y2017/0366912.html
> >>>
> >>>
> >>>
> >>> ....
> > -------------- next part --------------
> > An HTML attachment was scrubbed...
> > URL: <https://mail.music.vt.edu/mailman/private/sursound/
> attachments/20180124/16ff3135/attachment.html>
> > _______________________________________________
> > Sursound mailing list
> > ***@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
> > ***@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
> ***@music.vt.edu
> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
> edit account or options, view archives and so on.
>



--
Dr. Augustine Leudar
Artistic Director Magik Door LTD
Company Number : NI635217
Registered 63 Ballycoan rd,
Belfast BT88LL
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Steven Boardman
2018-01-29 11:15:58 UTC
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I have skimmed through it too. Nothing on curvature, but it’s very interesting non the less.
It needs a thorough read through

One of the many encoding and decoding solutions at grabbed my attention (it’s very comprehensive) is:

'‘D’ Channel (as in WXYZD)
The ‘D’ channel will encode as a normalized distance which can as one example be recovered as value of 0 (being in the head at the origin), 0.25 being exactly in the near-field, and up to 1 for a source rendered fully in the far-field. This encoding can be achieved by using an absolute value reference such as 0 dBFS or by relative magnitude and/or phase vs one or more of the other channels such as the “W” channel. Any actual distance attenuation resulting from being beyond the far-field is handled by the B-Format part of the mix as it would in legacy solutions

By treating distance m this way, the B-Format channels are functionally backwards compatible with normal decoders by dropping the D channel(s), resulting in a distance of 1 or “far-field” being assumed.

One method of encoding the D channel is to use relative magnitude of the W channel at each frequency. If the D channel's magnitude at a particular frequency is exactly the same as the magnitude as the W channel at that frequency, then the effective distance at that frequency is 1 or “far-field.” If the D channel's magnitude at a particular frequency is 0, then the effective distance at that frequency is 0, which corresponds to the middle of the listener's head. In another example, if the D channel's magnitude at a particular frequency is 0.25 of the W channel's magnitude at that frequency, then the effective distance is 0.25 or “near-field.” The same idea can be used to encode the D channel using relative power of the W channel at each frequency.'


It’s a DTS patent application too, so it also covers loads of options for matrix-ing.

Happy Monday

Steve


> On 29 Jan 2018, at 10:41, Augustine Leudar <***@gmail.com> wrote:
>
> Thanks for the list Markus,
> I read the conclusions and abstracts for these papers and skimmed through
> them - I am also quite busy ! However none of them seem to investigate or
> suggest that the curvature of the wavefront and this curvatures interaction
> with pinna folds is a potential distance and size cue in the nearfiled. I
> did find this though which mentions it but doesnt really investigate (or
> reference a source unfortunately) :
>
> https://pdfs.semanticscholar.org/0664/8964b53ac8f812b0068088caa4838c3ba7ce.pdf
>
> On 24 January 2018 at 14:35, Markus Noisternig (IRCAM) <
> ***@ircam.fr> wrote:
>
>> Dear All,
>>
>> Here are some references:
>>
>> Brungart and Rabinowitz [1] showed that HRTF vary significantly for
>> sources in the proximity region (i.e. at distances less than 1m from the
>> head).
>> Lentz et al. [2] perceptually evaluated measured HRTFs at different
>> distances from the head, showing limits of noticeable differences between
>> near-field and far-field HRTFs.
>> Romblom and Cook [3] proposed near-field compensation filters.
>> Duraiswami et al. [4], Zhang et al. [5], and Pollow et al. [6] compute
>> HRTFs for arbitrary field points using spherical harmonics decomposition
>> (as an extension of the work of Evans et al. [7]).
>> Duda and Martens [8] evaluated simulation results on a spherical head model
>>
>> Have fun reading!
>>
>> Very best,
>>
>> Markus
>>
>> [1] D.S.Brungart,W.M.Rabinowitz:Auditorylocalizationof nearby sources.
>> head-related transfer functions. J. Acoust. Soc. Am. 106 (1999) 1465–1479.
>> [2] T. Lentz, I. Assenmacher, M. Vorländer, T. Kuhlen: Precise
>> near-to-head acoustics with binaural synthesis. Journal of Virtual Reality
>> and Broadcasting 3 (2006).
>> [3] D. Romblom, B. Cook: Near-field compensation for hrtf processing.
>> 125th Conv. Audio Eng. Soc., San Francisco, USA, 2008, no. 7611.
>> [4 ]R. Duraiswami, D. N. Zotkin, N. A. Gumerov: Interpola- tion and range
>> extrapolation of HRTFs. IEEE ICASSP, Montreal, Canada, 2004, 45–48.
>> [5] W. Zhang, T. D. Abhayapala, R. A. Kennedy, R. Du- raiswami: Modal
>> expansion of HRTFs: Continuous repre- sentation in frequency-range-angle.
>> ICASSP, Los Alami- tos, USA: IEEE Computer Society, 2009, 285–288.
>> [6] Pollow, M., Nguyen, K.-V., Warusfel, O., Carpentier, T.,
>> Müller-Trapet, M., Vorländer, M., and Noisternig, M. (2012). “Calculation
>> of Head-Related Transfer Functions for Arbitrary Field Points Using
>> Spherical Harmonics Decomposition,” Acta Acust United Ac, 98, 72–82.
>> doi:10.3813/AAA.918493
>> [7] M. J. Evans, J. A. S. Angus, A. I. Tew: Analyzing head- related
>> transfer function measurements using surface spher- ical harmonics. J.
>> Acoust. Soc. Am. 104 (1998) 2400– 2411
>> [8] R. O. Duda, W. L. Martens: Range dependence of the re- sponse of a
>> spherical head model. J. Acoust. Soc. Am. 104 (1998) 3048–3058.
>>
>>
>>> On 24 Jan 2018, at 15:01, John Merchant <***@mtsu.edu> wrote:
>>>
>>> Tom Smurdon and Peter Stirling of Oculus presented research on
>> near-field HRTF for VR at last fall's OC4. The video of that talk is
>> available here:
>>> https://www.youtube.com/watch?v=l7mhXRB9PA4
>>>
>>> ________________________________________
>>> From: Sursound <sursound-***@music.vt.edu> on behalf of
>> ***@mail.telepac.pt <***@mail.telepac.pt>
>>> Sent: Tuesday, January 23, 2018 8:12 PM
>>> To: Surround Sound discussion group
>>> Subject: Re: [Sursound] A submittal for a patent on Ambisonics?
>>>
>>> Citando Augustine Leudar <***@gmail.com>:
>>>
>>>> Hi Jack,
>>>>
>>>> Aside from ILDs, ITDs, I also wondered if the pinna was able to
>> distinguish
>>>>
>>>> very close sound sources due to the fact the wavefront would be much
>> more
>>>>
>>>> curved almost spherical to the degree that it would be different
>> pressure
>>>>
>>>> present at different folds of the pinna (ie very close up sound slike
>> a
>>>>
>>>> mosquito) . I dont think theres been much done on that...
>>>
>>> Hi Augustine,
>>>
>>> I think "there has been done quite a lot on that"... 😉
>>>
>>> (Reproduction of near-field audio sources)
>>>
>>> Beside of spherical waves (and their consequences) we should not
>>> overlook that any high-frequency emitting (annoying) mosquito next to
>>> your left ear would be heard much softer at your right ear, the head
>>> shadow being even more relevant at close distances.
>>>
>>> BR
>>>
>>> Stefan
>>>
>>> P.S.: It is important to know about the "depth" of a mosquito audio
>>> object relative to your head, both in VR and in real life...
>>>
>>>> On 23 January 2018 at 11:58, jack reynolds <***@gmail.com>
>>>>
>>>> wrote:
>>>>
>>>>> It looks like a method for binaural rendering with multiple distance
>> HRTFs.
>>>>>
>>>>>
>>>>>
>>>>> Ambisonics could be one of the inputs, but it seems to be aimed more at
>>>>>
>>>>> object based virtual reality, where the listener is more likely to come
>>>>>
>>>>> very close to an audio source.
>>>>>
>>>>>
>>>>>
>>>>> Most HRTFs are currently measured at 1m distance, so any objects closer
>>>>>
>>>>> than 1m are not currently rendered correctly.
>>>>>
>>>>>
>>>>>
>>>>> Far field HRTFs are closer to plane waves, whereas close up audio
>> objects
>>>>>
>>>>> emit more spherical waves, creating greater differences in interaural
>> time
>>>>>
>>>>> difference (ITD).
>>>>>
>>>>>
>>>>>
>>>>> Jack
>>>>>
>>>>>
>>>>>
>>>>> On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com>
>>>>>
>>>>> wrote:
>>>>>
>>>>>
>>>>>
>>>>> I don't know a lot about patent law, but is this an attempt to tie up
>> our
>>>>>
>>>>> beloved Ambisonics?
>>>>>
>>>>>
>>>>>
>>>>> http://www.freepatentsonline.com/y2017/0366912.html
>>>>>
>>>>>
>>>>>
>>>>> ....
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>>> Sursound mailing list
>>> ***@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
>>> ***@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
>> ***@music.vt.edu
>> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
>> edit account or options, view archives and so on.
>>
>
>
>
> --
> Dr. Augustine Leudar
> Artistic Director Magik Door LTD
> Company Number : NI635217
> Registered 63 Ballycoan rd,
> Belfast BT88LL
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Augustine Leudar
2018-01-29 10:26:06 UTC
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I had a look at the first half where they explained the theory but again
it seemed to be entirely focussed on head shadowing as a nearfield cue -
couldnt see anything about the curvature of the wavefront -..... very busy
so didnt watch the second half - seemed the theory was in the first
half.....

On 24 January 2018 at 14:01, John Merchant <***@mtsu.edu> wrote:

> Tom Smurdon and Peter Stirling of Oculus presented research on near-field
> HRTF for VR at last fall's OC4. The video of that talk is available here:
> https://www.youtube.com/watch?v=l7mhXRB9PA4
>
> ________________________________________
> From: Sursound <sursound-***@music.vt.edu> on behalf of
> ***@mail.telepac.pt <***@mail.telepac.pt>
> Sent: Tuesday, January 23, 2018 8:12 PM
> To: Surround Sound discussion group
> Subject: Re: [Sursound] A submittal for a patent on Ambisonics?
>
> Citando Augustine Leudar <***@gmail.com>:
>
> > Hi Jack,
> >
> > Aside from ILDs, ITDs, I also wondered if the pinna was able to
> distinguish
> >
> > very close sound sources due to the fact the wavefront would be much
> more
> >
> > curved almost spherical to the degree that it would be different
> pressure
> >
> > present at different folds of the pinna (ie very close up sound slike
> a
> >
> > mosquito) . I dont think theres been much done on that...
>
> Hi Augustine,
>
> I think "there has been done quite a lot on that"... 😉
>
> (Reproduction of near-field audio sources)
>
> Beside of spherical waves (and their consequences) we should not
> overlook that any high-frequency emitting (annoying) mosquito next to
> your left ear would be heard much softer at your right ear, the head
> shadow being even more relevant at close distances.
>
> BR
>
> Stefan
>
> P.S.: It is important to know about the "depth" of a mosquito audio
> object relative to your head, both in VR and in real life...
>
> > On 23 January 2018 at 11:58, jack reynolds <***@gmail.com>
> >
> > wrote:
> >
> >> It looks like a method for binaural rendering with multiple distance
> HRTFs.
> >>
> >>
> >>
> >> Ambisonics could be one of the inputs, but it seems to be aimed more at
> >>
> >> object based virtual reality, where the listener is more likely to come
> >>
> >> very close to an audio source.
> >>
> >>
> >>
> >> Most HRTFs are currently measured at 1m distance, so any objects closer
> >>
> >> than 1m are not currently rendered correctly.
> >>
> >>
> >>
> >> Far field HRTFs are closer to plane waves, whereas close up audio
> objects
> >>
> >> emit more spherical waves, creating greater differences in interaural
> time
> >>
> >> difference (ITD).
> >>
> >>
> >>
> >> Jack
> >>
> >>
> >>
> >> On 23 January 2018 at 11:18, Bearcat Şándor <***@gmail.com>
> >>
> >> wrote:
> >>
> >>
> >>
> >> I don't know a lot about patent law, but is this an attempt to tie up
> our
> >>
> >> beloved Ambisonics?
> >>
> >>
> >>
> >> http://www.freepatentsonline.com/y2017/0366912.html
> >>
> >>
> >>
> >> ....
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> Sursound mailing list
> ***@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
> ***@music.vt.edu
> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here,
> edit account or options, view archives and so on.
>



--
Dr. Augustine Leudar
Artistic Director Magik Door LTD
Company Number : NI635217
Registered 63 Ballycoan rd,
Belfast BT88LL
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