Hi Richard, In terms of literature for general HOA decoding, the parts are all around, I personally like the papers by Franz Zotter cause they present all the relevant information in a clear and usable manner. The All-round Ambisonic Panning and Decoding paper in JAES I think has most of the stuff you’ll need, and not only for the specific method.
In terms of open code there are not so much stuff around. As the rest of the people mentioned, one is Aaron Heller’s ambisonic toolkit, in Matlab, which is very extensive! https://bitbucket.org/ambidecodertoolbox/adt.git I have also released a Matlab library in a more educational manner, not so much for efficiency as for readability, you can find it if you want to have a look in: http://research.spa.aalto.fi/projects/ambi-lib/ambi.html This implements some recent decoders too, including the ALLRAD method mentioned before, and another interesting one called CSAD (constant-angular spread), which has constant energy vector magnitude and zero angular error. You can also check energy/velocity vector plots for any decoder that you choose to implement. Could be a good starting point for making your own code. Additionally, a powerful but more complicated is the decoder generator of Davide Scaini, from University of Pompeau Fabra and Barcelona Media, which converges on an optimal decoder by iterative numerical optimization on the velocity/energy vectors, in Python. You can find the implementaiton in: https://github.com/BarcelonaMedia-Audio/idhoa Good luck with your project! Archontis Politis ________________________________________ From: Sursound [sursound-boun...@music.vt.edu] on behalf of Dave Malham [dave.mal...@york.ac.uk] Sent: 20 February 2016 20:56 To: Surround Sound discussion group Subject: Re: [Sursound] Ambisonic Decoder Design Resources I would definitely recommend Aaron's decoder toolkit and, in fact, the whole oeuvre from the Benjamin-Lee-Heller group (BLaH). This can be found at http://www.ai.sri.com/ajh/ambisonics/ Dave On 20 February 2016 at 17:58, Jörn Nettingsmeier < netti...@stackingdwarves.net> wrote: > On 02/20/2016 06:22 PM, Richard Graham wrote: > >> Hi Archontis, >> >> I would like to design decoders for 2d and 3d arrays, 1st through >> 3rd order (at least), both regular and irregular arrays. C code >> examples would be incredibly helpful as I plan to develop decoders >> for Pd and Max. >> > > Fons' ambdec is GPL, and it comes with a nice set of example setups. > It's C++, but the way Fons uses it, it reads pretty much like plain C. > After all, a dsp loop is a dsp loop... > > Most importantly, I’d like to figure out how to calculate these >> coefficients myself and I am having trouble finding literature on >> how to do that. I have reached out to a few folks who used their own >> programs to calculate coefficients. Essentially, I’d like to build >> my own program in the C programming language. >> > > Aaron Heller has a Matlab/Octave toolkit out that will generate matrices > for you, and it's completely open. But it relies on quite complex > functions of the framework... His solutions are used at CCRMA, to > great effect. Probably your best starting point. > > Richard has one but keeps it proprietary, Fons has one but also doesn't > like to part with it (although he has been very generous about > generating custom Ambdec setups for people, me included). > > For the nitty-gritty, check out the papers from recent Ambisonics > symposia and the ICSA conferences. Talk to Thomas Musil from Graz for > the old-school, lovingly hand-optimized matrix approach, or to Zotter et > al. for the All-Rad approach that works for arbitrary setups but is > quite complex and kind of brute-forceish. I can dig them up for you if you > can't find them. > > Shortly, I will have access to a 16-channel ring on the horizontal >> plane and a b-format cube. This system will be modular and >> configurable into irregular setups, too. >> > > nice! but unless you really need extremely high horizontal resolution for > research purposes or a truly humongous listening area, a better use for all > those speakers would be to make a more or less uniform 3D rig. > gets you a nice dodecahedron for full third-order all around. > > > best, > > > jörn > > > > -- > 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. > -- As of 1st October 2012, I have retired from the University. These are my own views and may or may not be shared by the University Dave Malham Honorary Fellow, Department of Music The University of York York YO10 5DD UK 'Ambisonics - Component Imaging for Audio' -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20160220/829dd4d1/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.
