Re: [xine-user] Could we have Dolby Headphone Technology in Xine?

[Michael R. <mr...@us...>]

Hi,

> I'm new to the list. First of all, I want to say "hello" & "thank
> you" to all the members of the Xine development team and the users'
> community.
>
> I've been "playing" with a couple of Windows' DVD players that had
> implemented Dolby Headphone encondig
> (http://www.dolby.com/dolbyheadphone/). Wow! I was amazed!
> Ok, nothing compares to the "real" 5.1 stuff, but as a user-story
> about this technology says, when you have no choice but headphones to
> listen something... then Dolby Headphone is the way to go.
>
> So I'd like to know if it would be possible to have this on Xine
> too... some day.
> I must say I'm new to the Linux sound architecture (ok... not only to
> the sound architecture...), so I really don't know if this should be
> implemented by something in the kernel, by ALSA, by OSS...

Since this basically means digital signal processing the multichannel 
signal down to stereo in some magical way, it would definitely live in 
userland and not in the kernel.

> whatever... and I don't know if this would mean paying royalties to
> the Dolby Laboratories either.

Using the term "Dolby Headphone" certainly would. But even the basic 
ideas of simulating surround sound with two channels through signal 
processing might be patented by someone.

> Can anybody explain here if this is possible, and how difficult (or
> not) it could be?

At first someone has to find out, how these things work. And I don't 
think Dolby would donate us their specs.
So unless any DSP guru writes a free virtual surround library, there is 
not much we can do here. Anyone knows any such project?

Michael

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