Re: [Bino-list] 3D sound

[Cédric André]

Le mardi 19 avril 2011 à 20:48 +0200, Martin Lambers a écrit :
> On 19/04/11 08:35, Cédric André wrote:
> > I'm doing a thesis on 3D sound for 3D cinema so I would be very
> > interested if Bino would decode ambisonics (first and higher order). But
> > right now, I'm using WFS for my experiment so I tweaked Bino a bit to
> > make it send OSC messages (www.opensoundcontrol.org) at every frame to
> > pilot the sound, using the OSCpack library.
> 
> I'm having a some difficulties understanding what exactly you are doing
> - obviously I have more of a graphics background then audio :)
> 
> Do you send video timestamps from within Bino to a different application
> that then produces synchronized audio output via wave field synthesis?
> In that case, doesn't this mean that the application needs to slow down
> or speed up audio output if the audio data playback speed does not match
> the timestamps?
> 
> After reading the "Introduction on OSC" on opensoundcontrol.org, I still
> have no idea what it actually is or does. Does it send synchronization
> time stamps around? Does it exchange audio or other media data?
> 
> Martin

Don't worry, I'm used to the fact that people usually know about one
field and not the other. I just forgot on which side of the line I was
^^

Basically, 3D sound systems are used in virtual reality often in
combination with 3D stereoscopic video. 3D sound, whatever the technique
used, aims at rendering a more realistic soundfield (with a better
spatial impression) than current surround sound.

My work basically is to bring this virtual reality technology in the
world of 3D cinema.essages you send

The system I work on, called the SMART-I²
http://www.limsi.fr/Individu/rebillat/index.html#research_3
uses Wave Field Synthesis (WFS) to render sound. It means that I can
precisely place a sound in a window corresponding to the visual 3D
window. 

I managed to get the sources of the open source movie Elephants Dream
(the 3D version). I will assign a soundfile to those object and the
resulting sound will be precisely coming from the place where I see the
object. OSC is used to communicate between the video PC (the one which
runs Bino) and the audio PC (the one that pilots the sound rendering
system). 

Basically OSC allows you how to easily send messages using a network
connection. It is widely used in the audio world to make things interact
(computers, motion capture, ...). You have to define the actual content
of your messages for them to be understood by the recipient.

Cédric