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 <[email protected]> wrote:

> Thank you very much Fons!
> 
> 
> On Fri, Jul 19, 2013 at 10:37 AM, Fons Adriaensen <[email protected]>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
>> [email protected]
>> 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
> [email protected]
> 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
[email protected]
https://mail.music.vt.edu/mailman/listinfo/sursound

Reply via email to