Hi all,
Wondering if anyone can help me with something that I am sure is obvious to those in the know.
The IEM object [ambi_decode3] produces an ambisonic decoder matrix (i.e. a bunch of floats) ... how can I turn that (with a source sound) into speaker feeds?
Would anyone have a sample patch?
Etienne
BTW: IOhannes, [ambi_decode2] [ambi_decode] [ambi_decode_cube] dont have help patches.
I think I've got this figured out. (but need help with matrices)
[ambi_decode3] spits out a matrix of numbers. Each line represents one speaker, each column (in each line) is the factor to multiply the appropriate component (or channel) of the incoming ambisonic signal.
If I am right then all I need to do is, for each row (i.e. speaker), multiple each col value to the appropriate component of the ambisonic signal ... then add them all up.... and that will be that particular speaker's feed.
I've got 2 libs loaded iem_matrix and iemmatrix. iemmatrix seems to have far more objects in it, but none of them have any help patches (and many need the * replaced with 'mul'). (OSX PD Extended).
I'm not too familiar with the concept of matrices ... but this is what I need to do:
Is there a matrix object that can have 9 inputs (i.e. second order 3D ambisonic signal) .... and then have 16 outputs (being my speakers). Then I pump in how each output is created by adding up the 9 imputs which have been factored?
I can do this outside of matrices but its gonna be shitloads of objects.
Etienne
On Wed, Jan 28, 2009 at 11:27 AM, e deleflie edeleflie@gmail.com wrote:
Hi all,
Wondering if anyone can help me with something that I am sure is obvious to those in the know.
The IEM object [ambi_decode3] produces an ambisonic decoder matrix (i.e. a bunch of floats) ... how can I turn that (with a source sound) into speaker feeds?
Would anyone have a sample patch?
Etienne
BTW: IOhannes, [ambi_decode2] [ambi_decode] [ambi_decode_cube] dont have help patches.
e deleflie wrote:
I've got 2 libs loaded iem_matrix and iemmatrix. iemmatrix seems to have far more objects in it, but none of them have any help patches (and many need the * replaced with 'mul'). (OSX PD Extended).
iemmatrix has plenty of help-patches (though i don't know where they are on Pd-extended)
just have a look at http://pure-data.svn.sourceforge.net/viewvc/pure-data/trunk/externals/iem/ie...
iem_matrix is an old library that is no longer maintained. all it's functionality has been integrated into iemmatrix.
I'm not too familiar with the concept of matrices ... but this is what I need to do:
Is there a matrix object that can have 9 inputs (i.e. second order 3D ambisonic signal) .... and then have 16 outputs (being my speakers). Then I pump in how each output is created by adding up the 9 imputs which have been factored?
I can do this outside of matrices but its gonna be shitloads of objects.
yes that is the main reason why i started writing iemmatrix.
the object you want is [mtx_*~ 16 9]
fgm,sdar IOhannes
iemmatrix has plenty of help-patches (though i don't know where they are on Pd-extended)
just have a look at http://pure-data.svn.sourceforge.net/viewvc/pure-data/trunk/externals/iem/ie...
great ... thankyou.
I can do this outside of matrices but its gonna be shitloads of objects.
yes that is the main reason why i started writing iemmatrix.
the object you want is [mtx_*~ 16 9]
so easy! (when you know how).
For posterity's sake ... if anyone is googling how to get speaker feeds from iem_ambi3, the answer is just to route the output of iem_ambi3 into a mtx_*~ object ... where the input signals are the ambisonic components and the outputs are the speaker feeds.
Etienne