[LAD] [ANN] jack-file 1.0

Robin Gareus robin at gareus.org
Tue Jul 5 11:54:38 UTC 2011


Hi Dan,

On Jul 5, 2011, at 12:24 PM, Dan Muresan wrote:

> Hi, and thanks for checking out my project.
> 
>> 1) make fails when it can't find help2man. it then complains (twice)
>> file2jack isn't found either (an ls after the fact shows it is):

I've stumbled over this one, too.. I did not know help2man. very handy tool!

> Well, help2man is listed as a build dependency, and I don't think it's
> proper style to verify dependencies in the makefile. In ./configure,
> yes -- but I'm not using one.
> 
>> 2) floating point exception when command issued without options:
> 
> That, indeed, is not nice. It happened because I left the arg parsing
> routine open till the last moment. Fixed in git.
> 
> To tell the whole story, I was hoping eventually to make both
> file2jack and jacktransportloop infrastructure-apps that could be
> controlled via stdin. So file2jack could start with nothing, and
> accept commands to add/remove files to the transport timeline.

nice!  1+

I suppose one could do that already with ecasound but I never
manage to remember the ecasound syntax to do that. 
I hope file2jack will keep it simple. 

Are you planning to add other decoder backends? If file2jack could play
sound from .avi, .mov and .mp3s, etc along to jack-transport, 
I could finally retire the kludgy jplay2 http://rg42.org/oss/jplay2/ player.

jacktransportloop is a very nifty tool; but it's not very accurate:
Calling jack_transport_locate() will make jackd go back to the "Starting" state:
http://jackaudio.org/files/docs/html/transport-design.html
Just launch some other jack-transport apps (e.g. ardour with a few tracks)
and you'll notice a short hiccup.

One alternative would be to just wrap the timecode internally in file2jack
(fold back, modulo) and keep going.. what do you think?

> Plus there would be a tkJackTransport app that actually scrolls the
> timeline (unlike gjacktransport, which is unhelpful when the transport
> overshoots the display limit) and has a loop checkbox and two time
> entries. I couldn't fit this in the first release. If anybody wants to
> help...

You can tell gjacktransport the start/end position of its timeline on startup:
   gjacktransport 10 100.2 # from 10 seconds -> 100.2 seconds
and one can also write a custom .rc file which can include N<99 predefined ranges 
and load it with  gjacktransport -l <file> on startup e.g.
http://gjacktransport.git.sourceforge.net/git/gitweb.cgi?p=gjacktransport/gjacktransport;a=blob;f=src/gjacktransportrc

It would not be too hard to add an OSC interface so that one can update those from an external app. But depending on your goals (loop checkbox, paging, maybe even display audio-chunk position, etc) you may indeed want a custom application.

> But otherwise -- did it work for you when you passed proper args

yes.

An *option* to specify JACK ports to auto-connect would be nice.
and I'd like to file a feature request for libSRC integration instead of calling 'sox'.

Cheers!
robin






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