Dolby Headphone Encoding

[nightstrm]

Not sure how much is known in the open source community about the inner-workings of Dolby Headphone, but I think it would be a nice option for those who encode movies for playback on their iPod/portable devices but still want some of the surround effect.

I had the privilege of demoing the technology at Dolby Labs when it was first introduced and must say that it can produce some pretty neat effects. Now that we're getting DPL2 support, maybe this can be considered?

[jbrjake]

Though I could be wrong, I think maurj would need a Dolby Headphone equivalent of these phase-shift charts: http://en.wikipedia.org/wiki/Dolby_Pro_ ... g_Matrices

[nightstrm]

Interesting, I'll have to keep my eyes open.

[jzietman]

Hey guys,

I've just been reading up on Dolby Headphone and getting rather excited about the possibilities. Has anyone heard anything about implementations of DH on macs or even encoded directly into the audio track of a video file?

Sorry for resurrecting such an old thread...

jzietman

[rhester]

Honestly - if you've tried it, it's crap. That having been said, I'm unaware of any effort towards this in HandBrake, and wouldn't expect any, given that it requires hefty licensing fees to be paid to Dolby (whether or not your implementation is actually certified).

Rodney

[realityking]

*cough* and who pays the license fees for things like mpeg2, H.264, MP3, Dolby Digital, DTS and so on?

[rhester]

AFAIK, MPEG-2 does not require a licensing fee. H.264 definitely doesn't. Franhoufer might be [Censored] about MP3, but it's so universal that I doubt they even track it. Dolby Digital doesn't require a fee unless you are certified, and we are not using their reference implementation (the lack of proper 90 degree bending of the backchannels for our "DPL2" means we aren't actually doing Dolby encoding). DTS is pass-through, so we aren't encoding and thus not subject.

Rodney

[realityking]

MP3: 2.50$ - 5$
MPEG2: 2.50 $
H.264: 0.10 $
AAC:: 0.98 $
those are the ones I found sources on so I stand corrected on the other ones (altrough I'm surprised that dts/dd decoding isn't patented)


However AFAIK none of these has been tested in a court case regarding OSS software

[jzietman]

It's crap? Sad... it sounded like such a good idea. I've been using it with stereophonic music encodes in foobar2000 (running using darwine), and it does make it easier to listen to than when normally using headphones (sound isn't coming from inside my skull), but I haven't managed to find a way to get it working in a mac-supported dvd player applicatin yet, so I don't know how it works there.

Thanks for your response!

[rhester]

MP3: 2.50$ - 5$
MPEG2: 2.50 $
H.264: 0.10 $
AAC:: 0.98 $

Wow. Damn. Urm...yeah. OK, I was wrong.

And we were worried about libdvdcss? *LMFAO*

those are the ones I found sources on so I stand corrected on the other ones (altrough I'm surprised that dts/dd decoding isn't patented)

With what you found, it probably is.

Rodney

[nightstrm]

Honestly - if you've tried it, it's crap. That having been said, I'm unaware of any effort towards this in HandBrake, and wouldn't expect any, given that it requires hefty licensing fees to be paid to Dolby (whether or not your implementation is actually certified).

Rodney

I was actually somewhat impressed with the Dolby Headphone demo I was a part of in early 2000 -- granted it was at Dolby's headquarters in San Francisco as part of a press demo so that could have influenced things a bit.

[rhester]

I wasn't really impressed with the Dolby demos I've heard (http://www.dolby.com/consumer/technology/headphone.html), but maybe it's just my ears.

Rodney

[79DC]

Hey guys,

I've just been reading up on Dolby Headphone and getting rather excited about the possibilities. Has anyone heard anything about implementations of DH on macs or even encoded directly into the audio track of a video file?

Sorry for resurrecting such an old thread...

jzietman

Hi,

I use to encode dvd for my pda with a dolbyheadphone soundtrack. I wrote a tutorial but it's for windows only.
If you're interested you can find it at: http://pagesperso-orange.fr/79.delta.charlie/
It's in french but google is your friend.

[rhester]

I have DH encoding (using AC3 hints on the size of the mixing room to automatically decide between DH1 and DH3) mostly working in zero-point test code outside of HandBrake using convolution on the audio stream. Once I've bulletproofed the approach a bit I intend to approach the general development community to see how much they might want to bite off for this one...because honestly it will require considerable effort for rather little payoff.

Rodney

[nightstrm]

I have DH encoding (using AC3 hints on the size of the mixing room to automatically decide between DH1 and DH3) mostly working in zero-point test code outside of HandBrake using convolution on the audio stream. Once I've bulletproofed the approach a bit I intend to approach the general development community to see how much they might want to bite off for this one...because honestly it will require considerable effort for rather little payoff.

Rodney

At this point, I'm not sure I want it anymore. I'd be very tempted to trash my encodes and start over again... for the 3rd or 4th time now.