Hi Joseph - yes I did - and that was because there are two main areas of non-linearity in perception, to do with actual proximity in real environments: "peripersonal space" and "auditory looming" - and these are not easily amenable to acoustic-only treatments.
That doesn't mean we can't take them into account, but it will take some oddball thinking My head hurts Dr. Peter Lennox Senior Lecturer in Perception College of Arts University of Derby, UK e: p.len...@derby.ac.uk t: 01332 593155 https://derby.academia.edu/peterlennox https://www.researchgate.net/profile/Peter_Lennox -----Original Message----- From: Sursound [mailto:sursound-boun...@music.vt.edu] On Behalf Of Joseph Anderson Sent: 14 December 2015 20:23 To: Surround Sound discussion group <sursound@music.vt.edu> Subject: Re: [Sursound] vertical precendence and summing localisation (wallis and lee 2015) Hi Peter, You left out proximity in your panner. (Doh!) ;-) One of our postgrads (Dan Peterson <https://dxarts.washington.edu/people/daniel-peterson>) has been working on a doppler-panner that includes diffusion filtering and the proximity effect. (Of course, all built out of the SuperCollider version of the ATK <http://doc.sccode.org/Guides/Intro-to-the-ATK.html>.) The results are fairly convincing. The technique was used for Peterson's new piece Steilacoom, premiered on the recent UW DXARTS Concert <https://dxarts.washington.edu/events/2015-11-20/dxarts-fall-concert>. The plan is to make this code available as part of the ATK <http://doc.sccode.org/Guides/Intro-to-the-ATK.html> documentation. *Joseph Anderson* *http://www.ambisonictoolkit.net/ <http://www.ambisonictoolkit.net/>* On Fri, Dec 11, 2015 at 5:36 AM, Peter Lennox <p.len...@derby.ac.uk> wrote: > A reason for 'tinting' on the encode side might be this: > > Sometimes, when synthesing a 3-d soundscape, I find it useful to pan > decorrelated reverberant material upwards - this gives a sense of > upward-spaciousness, and can help with clariy and intelligibility of > sources (kind of directional release from masking) - it's also handy > when using reverb to simulate distant sources. > > Tinting on the decode side might interfere with that, whereas doing it > on the encode side gives the flexibility to choose. > > There's another thing - dynamic panning in trajectories overhead - > 'tinting' would allow a slight phasy effect to interact with a doppler > effect to emphasise that passing overhead sensation - and intuitively, > it makes sense to combine these parameters in a single plugin. > > I quite like the idea of dedicated dynamic overhead panners... > > But then I quite like the idea of "straight line panners"... which > could actually incorporate parameters for object velocity and > distance, utilising amplitude, EQ and dry/reverb, all in one plugin. > > And I fancy the idea of 'flocking, chasing and scattering' panners > > and 'self motion panners' - that can be loaded up with a bunch of > sources with nominal positions featuring varying distances, so that as > the first-person listener virtually moves through the virtual > environment, auditory parallax is preserved. > > Oh, and whilst I'm writing to Santa, a 'biological motion' module, > that can impart the characteristic locomotion cues to a given source - > complete with optional gravity, friction, mass parameters. > > And I want that by the 25th, please... > > > Dr. Peter Lennox > Senior Fellow of the Higher Education Academy Senior Lecturer in > Perception College of Arts University of Derby > > Tel: 01332 593155 > ________________________________________ > From: Sursound [sursound-boun...@music.vt.edu] On Behalf Of Augustine > Leudar [augustineleu...@gmail.com] > Sent: 11 December 2015 13:10 > To: Surround Sound discussion group > Subject: Re: [Sursound] vertical precendence and summing localisation > (wallis and lee 2015) > > Hi Bo, > I googled "tinting" in relation to this but couldn't find any papers - > could you point me in the direction of these demonstrations/links ? > The thing is virtually all the HRTF info related to vertical > localisation is above 4 khz. The device we made allowed you to move > sounds up and down, and horizontally with a wii controller - it worked > quite well but we did cheat a little by just making sounds more high > pitched when they went upwards as well as convolving them with > directional bands but this wouldn't work with all sounds. > > On 11 December 2015 at 12:54, Bo-Erik Sandholm <bosses...@gmail.com> > wrote: > > > I just want to say that when I read Joseph's mail I feel like > > christmas > has > > come early this year :-) > > > > I have been thinking about headtracked binaural listening for a > > couple of years and discussing it here and in other forums. > > > > The goal is to make it possible to listen to ambisonics first order > > with earphones with head tracking usen open source programs and procedures. > > > > > > I do not think we should wait until it is possible to create a > > individual HRTF for a everey day nontechnical person. > > > > This is avaliable: > > Software and hardware to do it with software written by > > http://www.matthiaskronlachner.com/?p=2015 or the Ambiexplorer on > > the phone with the same effort to build the head tracker bu also t > > adding a blutooth transmitterand and using another firmware. > > > > > > I have been thinking of taking another way to the goal. > > > > What I have been thinking of is a tinted head tracking binaural > > decoder > (I > > did not know the principle had a name) > > > > My take on the decoder is that it > > - below ~ 4kHz it should use standard HRTF decoding and have a > > few profiles selectable on the width of the head, > > ignoring individual ear shape effects above 4kHz. > > > > - tinting used to improve the height perception in binaural > > decoding, tinting subsituting for HRTF above 4kHz for height. > > tinting has shown it is possible to add height information to > > Stereo, This has been demonstrated. > > > > - I want the shoulder reflections to be taken in to account, I > > belive the varying impact of a comb filter effect of the shoulder > > reflection is VERY important. > > - the software should be controlled by parameters for > > head tilt related to shoulders and head versus body turning > > - maybe also the normal distance from the ears to the > > shoulders, but I do not think this is very important as we adjust to > > clothes on shoulders very easily. > > > > I belive we should take inspiration from UNIX principles when > > creating > the > > software, that is to use a chain of software that each does one > > thing > well > > and do not have to be rewritten all the time, A number of VST > > modules > that > > can be chained for could be the solution. > > > > We already have a number of the needed modules, the advantage of > > modules > is > > that they can be replaced or switched between. > > > > - Ambisonic rotation and tilt controlled by OSC in VST - > > ambix_rotator > for > > example > > - Binaural decoder, Ambix_binaural, Tinted binaural decoder - not > > available > > - Shoulder reflections - I believe the shoulders are in many cases > > left out of the HRTF sets. > > If not we work with the difference intoduced when turning the > > head in relations to the fixed shoulders. > > > > Reaper DAW that I use is not free (shareware) but very low cost, > > > > Head tracking module, > > http://www.rcgroups.com/forums/showthread.php?t=1677559 > > - I hope to get assistance to make two modifications to the > > firmware > and > > hardware, > > the first is to change the output syntax of the data stream to OSC. > > The second is to add a second 9DOF sensor on a cable and use > > this to track shoulder movement. > > > > Best Regards > > Bo-Erik Sandholm > > Stockholm > > > > Amateur ambisonic recordist > > Interest in sound reproduction since beginning of 1960's. > > Ex Network Engineer and unix system manager Not a Programmer now for > > 35 years :-) > > > > > > > > > > > > > > > > 2015-12-10 21:05 GMT+01:00 Joseph Anderson < > > j.ander...@ambisonictoolkit.net> > > : > > > > > I'd just add here that a sensible approach would be to use (or > > > design) > a > > > 'tinted' decoder. That is, a decoder that includes frequency (& or > time) > > > domain filtering to color the soundfield on playback. > > > > > > Blue Ripple Sound <http://www.blueripplesound.com/> includes > > > tinted decoders > > > <http://www.blueripplesound.com/products/poa-decoding-vst> in > > > their technology portfolio. (Furse describes this in a patent > > > <http://www.google.com/patents/US20120014527>.) For the ATK > > > <http://www.ambisonictoolkit.net/wiki/tiki-index.php>, I've > > > thought > > about > > > including a help page in the SuperCollider documentation > > > <http://doc.sccode.org/Browse.html#Libraries%3EAmbisonic%20Toolkit > > > > on > > how > > > to go about implementing a tinted decoder, but haven't done so at > > > this time. > > > > > > The basic idea of 'tinting' is very simple: process the reproduced > > > soundfield in a way that 'enhances' or further achieves some > > > effect > you'd > > > like. To enhance elevation, we may choose to color the soundfield > > > in a > > way > > > that exaggerates this sense. We have two choices in the processing: > > > > > > 1. process the soundfield before decoding > > > 2. process the soundfield after decoding > > > > > > A combination of both gives the most flexible results, and the > > > best > > choice > > > really depends on what kind of decoding array you're working with. > > > If > you > > > have a full 3D array, choice 2 makes sense. Whereas, with a 2D > > > layout, processing the soundfield before decoding (option 1) is > > > probably the > best > > > idea. > > > > > > Option 1 is implemented like this: > > > > > > - decode soundfield to array of equally distributed 'virtual > > > loudspeakers' > > > - filter 'virtual loudspeakers', depending on direction > > > - re-encode soundfield > > > > > > Option 2 is this: > > > > > > - decode soundfield to array of real loudspeakers > > > - filter these, depending on direction > > > > > > Choosing the correct filtering to enhance elevation is the tricky part. > > > You'll want these to be phase matched. (Linear FIR, is an easy choice. > > > Phase matched 2nd-order IIR shelfs also work well.) There are many > papers > > > about modeling HRTFs, a simple choice is to just review the > > > suggested filtering for simple spherical head modeling. A very > > > quick search turns > > up > > > a paper from Duda and Brown > > > <http://www.ece.ucdavis.edu/cipic/files/2015/04/cipic_Brown_Duda98 > > > .pdf > >. > > > With listening in an Ambisonic soundfield, you need to remember > > > that > the > > > listener's head already applies the listener's own HRTF. The trick > > > will > > be > > > to enhance without unduly distorting. > > > > > > Something also useful to note: if you're a creative artist, you > > > can > > 'tint' > > > the soundfield for creative purposes. A simple example is what > > > might be what we call 'soundfield highlight'. The idea here is > > > that we'd > low-pass > > > all of the soundfield, except our 'highlight'. And notably, we can > steer > > > where the 'highlight' is located. (E.g., highlight different parts > > > of > the > > > soundfield.) We can think of this as 'directional masking', but > > > with a frequency dependence. I won't go into the exact details of > implementing a > > > signal flow to generate this effect, but the ATK > > > <http://www.ambisonictoolkit.net/wiki/tiki-index.php> includes all > > > the parts needed to do so. > > > > > > > > > My kind regards, > > > > > > > > > *Joseph Anderson* > > > > > > > > > > > > *http://www.ambisonictoolkit.net/ > > > <http://www.ambisonictoolkit.net/>* > > > > > > > > > On Thu, Dec 10, 2015 at 9:29 AM, Jörn Nettingsmeier < > > > netti...@stackingdwarves.net> wrote: > > > > > > > On 12/10/2015 04:59 PM, Peter Lennox wrote: > > > > > > > >> It does imply that an ambisonic panner plugin that incorporates > > spectral > > > >> manipulation would be more efficacious > > > >> > > > > > > > > noooooo! > > > > > > > > if it's an ambisonic panner, it doesn't change the spectrum. if > > > > it > > > changes > > > > the spectrum, it's not an ambisonic panner :) > > > > > > > > > > > > > > > > -- > > > > Jörn Nettingsmeier > > > > Lortzingstr. 11, 45128 Essen, Tel. +49 177 7937487 > > > > > > > > Meister für Veranstaltungstechnik (Bühne/Studio) Tonmeister VDT > > > > > > > > http://stackingdwarves.net > > > > > > > > _______________________________________________ > > > > 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. > > > > > > > -------------- next part -------------- An HTML attachment was > > > scrubbed... > > > URL: < > > > > > > https://mail.music.vt.edu/mailman/private/sursound/attachments/2015121 > 0/d099a481/attachment.html > > > > > > > _______________________________________________ > > > 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. > > > > > -------------- next part -------------- An HTML attachment was > > scrubbed... > > URL: < > > > https://mail.music.vt.edu/mailman/private/sursound/attachments/2015121 > 1/b039a53d/attachment.html > > > > > _______________________________________________ > > 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. > > > > > > -- > www.augustineleudar.com > -------------- next part -------------- An HTML attachment was > scrubbed... > URL: < > https://mail.music.vt.edu/mailman/private/sursound/attachments/2015121 > 1/d5078d5a/attachment.html > > > _______________________________________________ > 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. > > The University of Derby has a published policy regarding email and > reserves the right to monitor email traffic. If you believe this was > sent to you in error, please select unsubscribe. > > Unsubscribe and Security information contact: info...@derby.ac.uk > For all FOI requests please contact: f...@derby.ac.uk > All other Contacts are at http://www.derby.ac.uk/its/contacts/ > _______________________________________________ > 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. > -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20151214/023ce05c/attachment.html> _______________________________________________ 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. The University of Derby has a published policy regarding email and reserves the right to monitor email traffic. If you believe this was sent to you in error, please select unsubscribe. Unsubscribe and Security information contact: info...@derby.ac.uk For all FOI requests please contact: f...@derby.ac.uk All other Contacts are at http://www.derby.ac.uk/its/contacts/ _______________________________________________ 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.
