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introlab / odas

ODAS: Open embeddeD Audition System
MIT License
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Minimum number of microphones? #246

Open Jelt0 opened 3 years ago

Jelt0 commented 3 years ago

Hi,

I was wandering if there is a minimum number of microphones necessary in order to use the ODAS system. I am looking into building a measurement mic array an channels are rather expensive…

Thanks in advance!

SCWhite commented 3 years ago

I think you might need at least 3 mic to become a "array" (but very inaccurate) If you want to have Azimuth and Elevation angle, you must have at least 3 mic to form a 3D Coordinate System (xy,yz,xz) but I guess if you just need 1 dimension data, 2 will work.

Jelt0 commented 3 years ago

Would a 3-mic-array work with ODAS? I read in one of the ManyEars-papers, which is the framework ODAS is partly based on (if I am correct) that the ManyEars system requires at least 4 Mics.

Also, are there any restrictions on the array geometry to allow processing with ODAS? Do the mics have to be arranged in a circle, like with most of the MEMS-Arrays? Or would it be wise, to put one mic into the centre and place the three other mics on a circle around that, for a 4 Mic array for example?

Jelt0 commented 2 years ago

I did some tests using a ReSpeaker Core V2 with 6 microphones. I reconfigured the configuration file to use only 4 and after that only 3 of the microphones and monitored the results using the ODAS Studio visualisation. Results with 4 or 3 mics were significantly worth than with all 6 mics, but I did not get an error message even when using only 3 mics.

StuartIanNaylor commented 2 years ago

Hi does anyone know if a basic azimuth beamforming can be provided by a 2 mic and does anyone have a conf guide for best settings for the respeaker 2 mic? Also does the separation work with 2 mic as well?