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) < markus.noister...@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 <john.merch...@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-boun...@music.vt.edu> on behalf of > st...@mail.telepac.pt <st...@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 <augustineleu...@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 <jackreynolds...@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 <bearcatsan...@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 > > Sursound@music.vt.edu > > https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, > edit account or options, view archives and so on. > > _______________________________________________ > > Sursound mailing list > > Sursound@music.vt.edu > > https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, > edit account or options, view archives and so on. > > _______________________________________________ > 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. > -- Dr. Augustine Leudar Artistic Director Magik Door LTD Company Number : NI635217 Registered 63 Ballycoan rd, Belfast BT88LL -------------- next part -------------- An HTML attachment was scrubbed... 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