https://www.youtube.com/channel/UC6_696 ... CVsenXvbvQ
Youtube's Android app kan spela upp riktnings synkroniserad sfärisk video och ljudbild som styrs via telefonens läges sensorer.
Visningen av sfärisk video är inte nytt, men lägeskoordinering mellan bild och ljud i alla dimensioner är det allra senaste, även om ljudtekniken härstammar från sjuttiotalet.
Ljudet roteras i Ambisonics styrt av lägessensorerna därefter skerkonvertering till Binaural stereo.
Här har finns lite länkar till ljudtekniken bakom.
https://en.wikipedia.org/wiki/Ambisonics
Ossic X - ett tekniksprång?
viewtopic.php?f=10&t=63436
Nedan ett extrakt ur sursound mailinglistan som beskriver youtube implementeringen.
Bosse
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Hello all,
Some welcome news,
YouTube is now supporting ACN/SN3D FOA attached to a .mov video container as
uncompressed PCM audio.
This is great, as most of the world gets a lot of their content through
YouTube and now they'll all get to experience the power of Ambisonics!.
For now, it only works on Android, using the YouTube app, but hopefully soon
more platforms will be supported, if we create enough good content in this
format.
To contribute to that end, we've started our own channel, 360 Performances,
featuring music and performing arts in 360º video and recorded/mixed in
Ambisonics:
https://www.youtube.com/channel/UC6_696 ... CVsenXvbvQ
Hopefully this will turn into something viable, and we can continue doing
this for more artists and keep releasing new content in this manner.
As nowadays it's more about the number of subscribers/likes/views than the
quality of the content, please do subscribe to the channel if you like this
(and even if you don't like it, you can still subscribe...
Regards,
Albert
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We recorded this the regular way, multitrack using mono and stereo channels
and then we panned these channels into the 3rd order Ambisonic soundfield
using VST plugins (BlueRippleSound in my case), then you output the
16channel 3rd order FuMa mixdown file, convert it to ACN/SN3D (with another
Blue Ripple plugin), disregard the last 12 channels (which we'll keep for
when MPEG-H ever rolls around) and those first 4 channels are your B-format,
ACN/SN3D compatible.
------------------------
For now, the YouTube app handles the rotation and binaural decoding
dynamically using a generic HRTF (not sure which one).
I didn't own an Android myself either, but bought one just for these
reasons. Hopefully Apple will follow suit soon and starts supporting it on
their devices. Word is that they are much more difficult to deal with in
terms of developing for them, which is unfortunate, as they used to be the
innovators, but are acting more like IBM lately.
-------------------------------
Right now, the rotational feature is only supported on Android phones using
the YouTube app (unfortunately), not through the browser. The binaural
decoding is built into the app, using a generic HRTF, not sure about the
exact technical specs. I'm sure it's pretty bare bones currently, but
ideally in the future we would have Harpex style decoding.
---------------------
>
> I wonder why using uncompressed PCM instead of compressed AAC...
> --
> Marc
>
Hi Marc,
Apparently there are some issues with AAC decoding and certain Android
phones. You could upload it to the YouTube player and it will work fine on
that end, but certain mobile devices cannot handle it properly, so for now
they are trying to prevent those issues.
