etienne deleflie wrote:
finally! congratulations on being the first to get this out.
I've been waiting for exactly that combination of technology ... using
a phone's built-in gyro to do head-tracking and offer binaural decodes
of ambisonic material on something we all carry around ... smart
phones.
Well, I didn't think that anyone would take a recent joke so seriously:
to fix a phone at/on your head. But this is a great technology
demonstration, so I will start to take my own joke a bit more serious.
From now on... :-)
The first app is called AmbiExplorer and it's a first order decoder to
stereo, with the option of choosing binaural or virtual microphones.
You can peform soundfield rotation and microphone polar patten
selection. It will also work with the device's orientation sensors so
you could attach your device to headphones and have head-tracked
binaural listening.
The first part is overdue (and many thanks to Hector!), the second part
is a nice demonstration. But from a CE perspective, I highly doubt that
normal consumers would glue (in my terms) their smartphone to their
head.
This is why I am stunned that no known headphone manufacturer is using
any of all these widely available and really viable
motion-tracking/gyroscope chips, by now.
And: Things could be done in such an easier manner than ever before, by
now:
http://www.smyth-research.com/technology.html
The Realiser system includes a small device atop the headphone
headband and another small device at the front of the room, which
together monitor the position of the listener's head every five
milliseconds.
(Bayer Headzone is similar and overcomplicated, from a current perspective.
http://www.beyerdynamic.de/shop/headzone-headphone-surround-system.html
You won't need any base station for HT, by now!)
You can replace both former solutions with available motion tracking
ICs. 200 Hz is no problem by now.
(The Oculus Rift people give some specifications. I already wrote about
this, some time ago. )
Beside of this, I have written so often about the Wii control, iPhone
sensors, Glass motion sensors and Oculus Rift before that I seem
entitled to utter my private opinion. See also my recent posting of the
person who 3D-printed a frame for a smartphone as stereo display system
for a 3D glass. (VR systems need HT and fast visual updates. We are
all in-favour of head-tracked 5.1/Ambisonics decoding, so to speak)
Many thanks to Hector Centeno, anyway.
( It has become way too obvious that any current developments in audio
technology happen at an incredibly slow pace, compared to probably any
other area. This is probably also partially my own fault, just writing
about possible solutions and not actually doing them, cos I have a
full-time job and life... :-D I also would not blame the music or
audiophile industries, which don't know a lot about such complicated
topics like technology or music... On a more positive note, Hector has
written some of these apps for mobile devices which people (consumers)
might actually use in tough real-world/daily life conditions! This
wasn't about the usual Linux environment for connaisseurs, although
some other people might object that these apps would even not
exist without Linux... Maybe this was not the topic we should discuss!
O:-) )
Best,
Stefan Schreiber
If this combination of technology is not the future of ambisonics then
I dont think anything is!
Can I ask ... what is the latency on the head-tracking?
Etienne
On Wed, Dec 11, 2013 at 2:25 AM, Hector Centeno hcen...@gmail.com wrote:
Hello all,
I just wanted to share with this list information about two Android
apps I've been working on and that I will release soon. I made them
because I thought it would be great to be able to listen to ambisonic
recordings in a portable way without the need of a full size computer.
The first app is called AmbiExplorer and it's a first order decoder to
stereo, with the option of choosing binaural or virtual microphones.
You can peform soundfield rotation and microphone polar patten
selection. It will also work with the device's orientation sensors so
you could attach your device to headphones and have head-tracked
binaural listening.
The second app is called TetraFile and it's a port of the offline
command line utility part of Fons' TetraProc. I made this so I could
connect my portable recorder (in card reader mode) directly to my
phone via USB OTG, transfer the A-format files and do a conversion to
B-format and listen using AmbiExplorer. It will read your tetrafile
calibration files from your phone's storage.
More info and a video demo are available here: http://hcenteno.net/software.html
Any comments are welcome.
Best,
Hector Centeno
___
Sursound mailing list
Sursound@music.vt.edu
https://mail.music.vt.edu/mailman/listinfo/sursound
