Re: [Sursound] Looking for virtual mic equations
Hello Hector, If you're up for moving to SuperCollider for your work, check out the ATK: http://www.ambisonictoolkit.net We have all sorts of these things in-built. Along with lots of fancy tricks and spatial filters. Docs are found here: http://doc.sccode.org/Browse.html#Libraries%3EAmbisonic%20Toolkit My best, ~~ Joseph Anderson Artist: http://joseph-anderson.org Ambisonic Toolkit: http://ambisonictoolkit.net On 19 Jul 2013, at 4:02 pm, Hector Centeno wrote: > Thank you very much Fons! > > > On Fri, Jul 19, 2013 at 10:37 AM, Fons Adriaensen wrote: > >> On Fri, Jul 19, 2013 at 09:56:40AM -0400, Hector Centeno wrote: >> >>> I'm trying to implement virtual microphones derived from first order >>> ambisonic soundfields using Csound. I was wondering if anyone had any >>> resources to share with equations that would allow me to achieve this, >>> specifying azimuth, elevation and directivity of the mic. I've been >>> analyzing Fons' code for Tetraproc (the Virtmic class) but I'm having >>> difficulties understanding some parts of it (but I'll keep trying). I >> found >>> the paper "Has Ambisonics Come of Age?" by Bruce Wiggins wich contains >>> equations for doing this but it seems that it only takes azimuth angle in >>> consideration. >> >> Given >> >> A = mic direction azimuth >> E = mic direction elevation >> D = directivity, [0...1], 0 = omni, 0.5 = cardioid, 1 = fig-8 >> >> and assuming your B-format is FuMA, compute >> >> cw = sqrt(2) * (1 - D) >> cx = cos(A) * cos(E) * D >> cy = sin(A) * cos(E) * D >> cz = sin(E) * D >> >> and then the output signal for the mic is >> >> cw * W + cx * X + cy * Y + cz * Z >> >> 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) >> >> ___ >> Sursound mailing list >> Sursound@music.vt.edu >> https://mail.music.vt.edu/mailman/listinfo/sursound >> > -- next part -- > An HTML attachment was scrubbed... > URL: > <https://mail.music.vt.edu/mailman/private/sursound/attachments/20130719/a5cc7e60/attachment.html> > ___ > Sursound mailing list > Sursound@music.vt.edu > https://mail.music.vt.edu/mailman/listinfo/sursound -- next part -- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20130719/f37ef471/attachment.html> ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Looking for virtual mic equations
Thank you very much Fons! On Fri, Jul 19, 2013 at 10:37 AM, Fons Adriaensen wrote: > On Fri, Jul 19, 2013 at 09:56:40AM -0400, Hector Centeno wrote: > > > I'm trying to implement virtual microphones derived from first order > > ambisonic soundfields using Csound. I was wondering if anyone had any > > resources to share with equations that would allow me to achieve this, > > specifying azimuth, elevation and directivity of the mic. I've been > > analyzing Fons' code for Tetraproc (the Virtmic class) but I'm having > > difficulties understanding some parts of it (but I'll keep trying). I > found > > the paper "Has Ambisonics Come of Age?" by Bruce Wiggins wich contains > > equations for doing this but it seems that it only takes azimuth angle in > > consideration. > > Given > > A = mic direction azimuth > E = mic direction elevation > D = directivity, [0...1], 0 = omni, 0.5 = cardioid, 1 = fig-8 > > and assuming your B-format is FuMA, compute > > cw = sqrt(2) * (1 - D) > cx = cos(A) * cos(E) * D > cy = sin(A) * cos(E) * D > cz = sin(E) * D > > and then the output signal for the mic is > > cw * W + cx * X + cy * Y + cz * Z > > 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) > > ___ > Sursound mailing list > Sursound@music.vt.edu > https://mail.music.vt.edu/mailman/listinfo/sursound > -- next part -- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20130719/a5cc7e60/attachment.html> ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
Re: [Sursound] Looking for virtual mic equations
On Fri, Jul 19, 2013 at 09:56:40AM -0400, Hector Centeno wrote: > I'm trying to implement virtual microphones derived from first order > ambisonic soundfields using Csound. I was wondering if anyone had any > resources to share with equations that would allow me to achieve this, > specifying azimuth, elevation and directivity of the mic. I've been > analyzing Fons' code for Tetraproc (the Virtmic class) but I'm having > difficulties understanding some parts of it (but I'll keep trying). I found > the paper "Has Ambisonics Come of Age?" by Bruce Wiggins wich contains > equations for doing this but it seems that it only takes azimuth angle in > consideration. Given A = mic direction azimuth E = mic direction elevation D = directivity, [0...1], 0 = omni, 0.5 = cardioid, 1 = fig-8 and assuming your B-format is FuMA, compute cw = sqrt(2) * (1 - D) cx = cos(A) * cos(E) * D cy = sin(A) * cos(E) * D cz = sin(E) * D and then the output signal for the mic is cw * W + cx * X + cy * Y + cz * Z 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) ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
[Sursound] Looking for virtual mic equations
Hi, I'm trying to implement virtual microphones derived from first order ambisonic soundfields using Csound. I was wondering if anyone had any resources to share with equations that would allow me to achieve this, specifying azimuth, elevation and directivity of the mic. I've been analyzing Fons' code for Tetraproc (the Virtmic class) but I'm having difficulties understanding some parts of it (but I'll keep trying). I found the paper "Has Ambisonics Come of Age?" by Bruce Wiggins wich contains equations for doing this but it seems that it only takes azimuth angle in consideration. Thanks in advance, Hector -- next part -- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20130719/5f00c717/attachment.html> ___ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
