[mythtv-users] Re: MythTV & Jack

[Mark Knecht]

Hi Ross - thanks for responding.

On 9/13/05, Ross Campbell <ross.campbell at gmail.com> wrote:
> > On 9/7/05, Mark Knecht <markknecht at gmail.com> wrote:
> > >    Anyone here using Jack as your audio interface for MythTV? If so,
> > > would you mind sharing how you did it?
> 
> Mark,
> 
> I suspect that few of the people here know what jack is and why they
> would even want to try to get this working.

Most possibly true...

> 
> As a musician, I'm interested in jack for MIDI-in/out/through because
> of it's ultra-low latency, but far and away the best MIDI tools are
> currently on Windows and MacOS :( . Most people would never notice or
> need ASIO-like ultra low latency sound, but when you use your computer
> as a software synth for an external MIDI keyboard... trust me - 75
> milliseconds delay from keypress to sound is unacceptable.

Don't have to trust you. Been there, done that. I'm a musician too.

<SNIP>
> 
> So, the real question is:  Why would a mythtv user/developer care
> about using JACK for sound in MythTV?
> 
> The main benefits for MythTV I can see would be to have access to a
> JACK plugins for sound enhancement. (if anyone else sees other
> benefits I missed, please do tell :)

In my case I have headphones on and I'm working on a song.
(Ardour/Jack/synths/whatever) I also have MythTV open in a Window.
Since Jack has grabbed the sound hardware I cannot hear audio from
Myth. I'm very multi-tasking and like the TV on while I write music.
Music on TV increases my creativity. (OK, I'm a thief!) ;-)

I've been asked to do some music for a movie. I'm sent a DVD that has
some scenes and dialog. I start Myth, watch the DVD, and again have
access to my music creation tools while the DVD is running. Heck, I
watch a good commercial DVD and like the music. I'm in a good mood and
just want to play along. Maybe I want to record the audio from th DVD
along with my playing. Myth using Jack makes this possible.

With Myth operating through Jack I can do my work in the studio and
still have access to what Myth provides. Good for me.

> 
> I could envision taking advantage of LADSPA plugins (
> http://www.ladspa.org/ ) to provide graphic equalizers, different
> sound environment settings (living room, concert hall, outdoors,
> etc...), extra stereo separation, reverb?, high and low filters, noise
> cancellation using an external mic?, and the list goes on.

Sure, that's possible also, but not my main concern.
> 
> If many mythtv systems eventually have a MIC and camera for mythPhone
> use, I could also see a desire to have more audio/video processing
> abilities - maybe the ability to have mythPhone in a PiP with your
> buddy while you watch the same show? Maybe the ability to filter voice
> out of music files so that people could sing karaoke over the real
> music?
> 
> Anyway, JACK could be interesting for mythtv - I'm eager to know how
> far anyone else gets.
> 
> -Ross
> 

Cheers,
Mark