lieven moors:
>>
>>> I want to repeat the same Arp, until there is an update to the text file.
>>> One arp is allready
>>> loaded in each ringbuffer in main(). When the file is modified, a second one
>>> is added, and
>>> process skips to the second one. Since I have only space for two arps in the
>>> buffer, there
>>> should always be exactly one which is readable. I know it is a bit weird,
>>> but it seems to
>>> work, apart from the problem I described.
>>>
>>
>> sounds as if you might want to look into atomic pointer and/or integer
>> exchange instead, to get lock-free double buffering.
>>
>> ringbuffers are generally for passing streaming data/events.
>>
>>
> Could you give me a hint on how to use atomic pointers?
I've used the lockless lifo/fifo-queue implementations found in
midishare a few times. Those are really simple to use:
http://midishare.sourceforge.net/
First of all,
Apologies for cross-posting.
If it is not too much of a trouble, I was wondering if I could ask fellow
FOSS enthusiasts to help us in "digging" & "reddit-ing" our L2Ork
announcement posted on reddit and dig earlier today.
Links to the posts can be found below:
<http://www.reddit.com/r/reddit.com/comments/aa12z/who_says_penguins_cannot_
sing_introducing_l2ork/>
<http://digg.com/linux_unix/Introducing_L2Ork_World_s_First_Linux_Laptop_Orc
hestra>
Once again, apologies for the OT nature of this post.
Sincerely,
Ivica Ico Bukvic, D.M.A.
Composition, Music Technology
Director, DISIS Interactive Sound & Intermedia Studio
Assistant Co-Director, CCTAD
CHCI, CS, and Art (by courtesy)
Virginia Tech
Dept. of Music - 0240
Blacksburg, VA 24061
(540) 231-6139
(540) 231-5034 (fax)
ico(a)vt.edu
http://www.music.vt.edu/faculty/bukvic/
I'm happy to announce a new guitarix release
guitarix is a simple Linux Rock Guitar amplifier and is designed
to achieve nice thrash/metal/rock/blues guitar sounds.
Guitarix uses the Jack Audio Connection Kit as its audio backend
and brings in one input and two output ports to the jack graph.
Release 0.05.2-1 comes with some changes:
* remove dependency of the boost library
(Many thanks to "thrasher13b" for the patch)
* fix missing "./" in ./debian/rules reported
by GMag (AV Linux)
* add 2 Channel gain and delay chooser to the
Jconv settings widget.
* add scroll/zoom mode to the wave view
* reworked Jconv settings widget UI
* various GUI and feature clean-up's
have fun
Comments and suggestions are welcome.
________________________________________________________________________
The standalone version of guitarix is based on GTK2+.
But guitarix is also released as a suite of LADSPA plugins
and can be used in e.g. ardour.
guitarix is licensed under the GPL.
Project page with screenshots:
http://guitarix.sourceforge.net/
download:
http://sourceforge.net/projects/guitarix/
For capture, guitarix uses the external application
'jack_capture' (version >= 0.9.30) written by Kjetil
S. Matheussen. If you don't have it installed,
you can look here:
http://old.notam02.no/arkiv/src/?M=D
For extra Impulse Responses, guitarix uses the
convolution application 'jconv' created by Fons Adriaensen.
If you don't have it installed, you can look here:
http://www.kokkinizita.net/linuxaudio/index.html
I(hermann) use faust to build the prototype and will say
thanks to
: Julius Smith
http://ccrma.stanford.edu/realsimple/faust/
: Albert Graef
http://q-lang.sourceforge.net/examples.html#Faust
: Yann Orlary
http://faust.grame.fr/
regards
Hermann Meyer & James Warden
------------------------------------------
guitarix-dev team
hello everyone,
I am trying to write a c++/qt4 jack client which mix 2 inputs and has a jack
output. The problem is that currently jack gets zombified too often and I would
like some info on how can I debug the exact reason this happens. I suspect
it's the way the app is written and I am planning to rewrite it but I need
some advices first.
The way it's currently written makes use of mutexes and locks to pass the
data beetween a custom global buffer. Is this the reason for not synchronizing
good enough and zombifies jack or it's something else that screw things? Should
I use a ringbuffer (which, to my understanding is lock-free and doesn't need
mutexes) to get the work done, and if so, are there any jack2 example of this
or some hints for what I should be aware of? Or have I misunderstand something
completely?
Please, any recommendation of how I can eliminate this "jack zombified" thing
and understand the whole realtime issue is welcome.
Thank you in advance.
Dear fellow Linux enthusiasts and consortium members,
Please allow me to bring to your attention the upcoming L2Ork debut:
On December 4th Virginia Tech DISIS (<http://disis.music.vt.edu>) Linux
Laptop Orchestra (L2Ork, <http://l2ork.music.vt.edu>) will hold its first
sneak preview debut performance on Virginia Tech (VT) campus, Squires Studio
Theatre, starting at 7pm. Admission is free.
At noon on the same day, L2Orkists will also host a demo booth outside the
Commonwealth Ballroom in Squires Student Center (VT campus) demoing how
L2Ork works.
For additional info on L2Ork and a video preview of L2Ork in rehearsal:
<http://l2ork.music.vt.edu>
Facebook Event Page:
<http://www.facebook.com/home.php#/event.php?eid=180832548428&ref=mf>
Sincerely,
Ivica Ico Bukvic, D.M.A.
Composition, Music Technology
Director, DISIS Interactive Sound & Intermedia Studio
Assistant Co-Director, CCTAD
CHCI, CS, and Art (by courtesy)
Virginia Tech
Dept. of Music - 0240
Blacksburg, VA 24061
(540) 231-6139
(540) 231-5034 (fax)
ico(a)vt.edu
http://www.music.vt.edu/faculty/bukvic/
Hi,
I'm trying to do a simple effect in the frequency domain, nothing extraordinary.
I need to apply various gains to specific frequencies.
For this purpose, I want to process a 16bit audio input stream, block by block,
apply a hanning window, do a fft, now apply my effect, and then an inverse fft,
followed by overlap and add buffering.
For now, I'm simply trying to do all of this without applying any effect, just
to see if my time to frequency and back conversion is correct.
I managed to do this in Octave. Now, I'm trying to do it in C with fftw and the
sound I obtain is like "shivering". It's recognizable but severely altered. I've
spent hours on this, it just won't work.
Attached :
- freqfilter.m: my working octave version
- transform.h and transform.c: time -> frequency -> time routines
- transformtest.c: test program
Could anyone tell me what's wrong with this C code?
Thanks in advance
--
Olivier
Hi Nedko :)
today I tried to compile LADI, but it failed for openSuse 11.2 x86_64
and 64 Studio 3.0-beta3 x86_64. Please take a look at the attachments.
Cheers,
Ralf
suse11-2:/usr/src/ladish-0.1/flowcanvas # ./waf configure
Checking for program gcc : ok /usr/bin/gcc
Checking for program cpp : ok /usr/bin/cpp
Checking for program ar : ok /usr/bin/ar
Checking for program ranlib : ok /usr/bin/ranlib
Checking for gcc : ok
Checking for program g++ : ok /usr/bin/g++
Checking for g++ : ok
Checking for libgvc >= 2.8 : ok
Checking for gtkmm-2.4 >= 2.10.0 : ok
Checking for libgnomecanvasmm-2.6 >= 2.6.0 : ok
Checking for header boost/shared_ptr.hpp : ok
Checking for header boost/weak_ptr.hpp : ok
Global configuration
Install prefix : /usr/local
Debuggable build : False
Strict compiler flags : False
Build documentation : False
FlowCanvas Configuration
Auto-arrange : True
Anti-Aliasing : True
'configure' finished successfully (0.730s)
suse11-2:/usr/src/ladish-0.1/flowcanvas # ./waf
[snip]
'build' finished successfully (15.788s)
suse11-2:/usr/src/ladish-0.1/flowcanvas # ./waf install
[snip]
'install' finished successfully (0.074s)
suse11-2:/usr/src/ladish-0.1/flowcanvas # cd ..
suse11-2:/usr/src/ladish-0.1 # ./waf configure
[snip]
Install prefix : /usr/local
Build liblash : no
WARNING: D-Bus session services directory as reported by pkg-config is
WARNING: /usr/share/dbus-1/services
WARNING: but service file will be installed in
WARNING: /usr/local/share/dbus-1/services
WARNING: You may need to adjust your D-Bus configuration after installing jackdbus
WARNING: You can override dbus service install directory
WARNING: with --enable-pkg-config-dbus-service-dir option to this script
'configure' finished successfully (1.034s)
suse11-2:/usr/src/ladish-0.1 # ./waf configure --prefix=/usr
Checking for program gcc : ok /usr/bin/gcc
Checking for program cpp : ok /usr/bin/cpp
Checking for program ar : ok /usr/bin/ar
Checking for program ranlib : ok /usr/bin/ranlib
Checking for gcc : ok
Checking for program g++ : ok /usr/bin/g++
Checking for g++ : ok
Checking for dbus-1 >= 1.0.0 : ok
Retrieving D-Bus services dir : ok
Checking for uuid : ok
Checking for header expat.h : ok
Checking for glib-2.0 : ok
Checking for dbus-glib-1 : ok
Checking for gtk+-2.0 : ok
Checking for libglade-2.0 : ok
Checking for flowcanvas >= 0.4.0 : ok
boost headers : Version 1_39 (/usr/include)
==================
ladish-0.1 exported from 0d1ac13dd396785602ea157b5acb12f81da17b63
Install prefix : /usr
Build liblash : no
'configure' finished successfully (0.745s)
suse11-2:/usr/src/ladish-0.1 # ./waf
Waf: Entering directory `/usr/src/ladish-0.1/build'
[ 1/41] cxx: gui/canvas.cpp -> build/default/gui/canvas_3.o
[ 2/41] copy: daemon/dbus.service.in -> build/default/org.ladish.service
[ 3/41] git_ver: -> build/default/version.h
tarball from git revision 0d1ac13dd396785602ea157b5acb12f81da17b63
[ 4/41] cc: jack_proxy.c -> build/default/jack_proxy_1.o
[ 5/41] cc: catdup.c -> build/default/catdup_1.o
cc1: warnings being treated as errors
../jack_proxy.c: In function ‘jack_proxy_set_parameter_value’:
../jack_proxy.c:588: error: ‘type’ may be used uninitialized in this function
Waf: Leaving directory `/usr/src/ladish-0.1/build'
Build failed
-> task failed (err #1):
{task: cc jack_proxy.c -> jack_proxy_1.o}
suse11-2:/usr/src/ladish-0.1 #
root@64studio:/usr/src/ladish-0.1/flowcanvas# ./waf configure
Checking for program gcc : ok /usr/bin/gcc
Checking for program cpp : ok /usr/bin/cpp
Checking for program ar : ok /usr/bin/ar
Checking for program ranlib : ok /usr/bin/ranlib
Checking for gcc : ok
Checking for program g++ : ok /usr/bin/g++
Checking for g++ : ok
Checking for libgvc >= 2.8 : ok
Checking for gtkmm-2.4 >= 2.10.0 : ok
Checking for libgnomecanvasmm-2.6 >= 2.6.0 : ok
Checking for header boost/shared_ptr.hpp : ok
Checking for header boost/weak_ptr.hpp : ok
Global configuration
Install prefix : /usr/local
Debuggable build : False
Strict compiler flags : False
Build documentation : False
FlowCanvas Configuration
Auto-arrange : True
Anti-Aliasing : True
'configure' finished successfully (1.610s)
root@64studio:/usr/src/ladish-0.1/flowcanvas# ./waf
Waf: Entering directory `/usr/src/ladish-0.1/flowcanvas/build'
[1/9] cxx: src/Canvas.cpp -> build/default/src/Canvas_2.o
[2/9] cxx: src/Connectable.cpp -> build/default/src/Connectable_2.o
In file included from /usr/include/graphviz/gvc.h:20,
from ../src/Canvas.cpp:32:
/usr/include/graphviz/types.h:26:1: warning: "FALSE" redefined
In file included from /usr/lib/glib-2.0/include/glibconfig.h:9,
from /usr/include/glib-2.0/glib/gtypes.h:30,
from /usr/include/glib-2.0/glib/galloca.h:30,
from /usr/include/glib-2.0/glib.h:30,
from /usr/include/glib-2.0/gobject/gtype.h:26,
from /usr/include/glib-2.0/gobject/gboxed.h:26,
from /usr/include/glib-2.0/glib-object.h:25,
from /usr/include/glibmm-2.4/glibmm/containerhandle_shared.h:31,
from /usr/include/glibmm-2.4/glibmm/arrayhandle.h:24,
from /usr/include/glibmm-2.4/glibmm.h:27,
from /usr/include/gtkmm-2.4/gtkmm.h:29,
from /usr/include/libgnomecanvasmm-2.6/libgnomecanvasmm.h:29,
from ../flowcanvas/Canvas.hpp:24,
from ../src/Canvas.cpp:27:
/usr/include/glib-2.0/glib/gmacros.h:167:1: warning: this is the location of the previous definition
In file included from /usr/include/graphviz/gvc.h:20,
from ../src/Canvas.cpp:32:
/usr/include/graphviz/types.h:27:1: warning: "TRUE" redefined
In file included from /usr/lib/glib-2.0/include/glibconfig.h:9,
from /usr/include/glib-2.0/glib/gtypes.h:30,
from /usr/include/glib-2.0/glib/galloca.h:30,
from /usr/include/glib-2.0/glib.h:30,
from /usr/include/glib-2.0/gobject/gtype.h:26,
from /usr/include/glib-2.0/gobject/gboxed.h:26,
from /usr/include/glib-2.0/glib-object.h:25,
from /usr/include/glibmm-2.4/glibmm/containerhandle_shared.h:31,
from /usr/include/glibmm-2.4/glibmm/arrayhandle.h:24,
from /usr/include/glibmm-2.4/glibmm.h:27,
from /usr/include/gtkmm-2.4/gtkmm.h:29,
from /usr/include/libgnomecanvasmm-2.6/libgnomecanvasmm.h:29,
from ../flowcanvas/Canvas.hpp:24,
from ../src/Canvas.cpp:27:
/usr/include/glib-2.0/glib/gmacros.h:171:1: warning: this is the location of the previous definition
[3/9] cxx: src/Connection.cpp -> build/default/src/Connection_2.o
[4/9] cxx: src/Ellipse.cpp -> build/default/src/Ellipse_2.o
[5/9] cxx: src/Item.cpp -> build/default/src/Item_2.o
[6/9] cxx: src/Module.cpp -> build/default/src/Module_2.o
[7/9] cxx: src/Port.cpp -> build/default/src/Port_2.o
[8/9] copy: flowcanvas.pc.in -> build/default/flowcanvas.pc
[9/9] vnum_cxx_link: build/default/src/Canvas_2.o build/default/src/Connectable_2.o build/default/src/Connection_2.o build/default/src/Ellipse_2.o build/default/src/Item_2.o build/default/src/Module_2.o build/default/src/Port_2.o -> build/default/libflowcanvas.so build/default/libflowcanvas.so.2
Waf: Leaving directory `/usr/src/ladish-0.1/flowcanvas/build'
'build' finished successfully (14.397s)
root@64studio:/usr/src/ladish-0.1/flowcanvas#
Building LADI and installing LADI tools for 64 Studio 3.0-beta3 seems to
be fine, *when ignoring the warnings for flowcanvas*, but I had no time
to check if the installs will work. So compiling only for Suse failed.
Recent discussion on LAU morphed into an idea for an Ethernet driven
sound card, and as this is now becoming a real development the
suggestion was made that it would be better to transfer the discussion
here.
The rationale in brief:
No proprietry hardware soundcard needed.
Almost all modern computers have reasonably fast Ethernet connections.
Potentially up to 20 channels per card - reality will probably be a lot
different!
FOSS drivers to connect Ethernet to whatever audio server is on the
computer - looking at jack right now.
FOSS within the soundcard module so that protocols/algorythings can be
tuned for best results.
FOSH design enabling hardware to be developed and inproved by anyone.
A number of people have shown interest in this, and we are at the stage
of starting to knock together some basic hardware for a feasibility
study.
State of play:
On Mon, 23 Nov 2009 14:39:48 +0100 (CET)
karl(a)aspodata.se (Karl Hammar) wrote:
> Folderol:
> > On Sat, 21 Nov 2009 12:25:36 +0100 (CET)
> > karl(a)aspodata.se (Karl Hammar) wrote:
> >
> > <snip>
> >
> > > Would this project plan be ok:
> > >
> > > software and hw: Karl
> > > testing and spec's: Folderol
> > > publication via web: anyone??
> > >
> > > git repo: git://aspodata.se/openhw.git
> > > mailing list: hopefully this list, else I put one up at my site
> > > web site: ??
> > >
> > > intial platforms (both by Atmel):
> > > . ATNGW100 (cheap), and
> > > . AT91SAM9260-EK (expensive)
> > >
> > > Next step:
> > > . set up development platform
> > > . simple test with spi and shift registers
> > >
> > > Regards,
> > > /Karl
> >
> > This is all fine by me, but I would make quite clear that if someone
> > comes along with access to a {loadsamoney} spectrum analyser I'd be
> > perfectly happy to step back and take a more supporting role.
>
> Ok, I should get starting then.
>
> Regards,
> /Karl
Others would be welcome to come on board - pardon the pun!
--
Will J Godfrey
http://www.musically.me.uk
Say you have a poem and I have a tune.
Exchange them and we can both have a poem, a tune, and a song.
Wow! A lot been said since I opened my mouth :o
First an apology!
When I started this thread I CC'd LAU hoping to just bring interested
people over. I didn't expect the cross-post deluge that followed -
Sorry. I won't do it again :(
For those in doubt the original discussion started over on LAU as a
complaint about the state of USB support on Linux.
My take is very much like Karl's in many respects.
I want to keep well clear of any propriety issues such as patents,
licenses etc. You can't get much more 'free' that real analog audio,
and Ethernet is a pretty much universal and unencumbered standard. If
all the software and hardware remains open then I think we're pretty
much covered.
Another reason for going for a nuts & bolts build is that it will be a
*fun* challenge. I certainly do not expect broadcast standard feeds from
our first attempt, but if we can produce something that is reliable and
repeatable then I'm sure those that are more experienced than myself
will be able to point us in the right direction for fine tuning both
the hardware and software, but we really need a brick in place first.
Karl and I and some others I think more or less agreed that the first
step was to produce a simple development board with just two inputs as
a starter. The unit that Karl though most promising already has 16bit
DACs on board so a complete 2 in 2 out should be realisable fairly
quickly. For this first test, I'm not at all concerned about noise
levels. I think getting a reasonably low distortion conversion without
any discontinuities is the first target.
If the triggering of fast ADCs is controlled by a reasonably accurate
Xtal standard is doesn't really matter if the computer end drifts
about a bit, the odd lost packet should be recoverable and jack really
won't care as long as it's buffers are filled and emptied within the
overall time frame.
I know very little about networking, but the Wikipedia link very
much confirms my early thoughts that there aren't
any effective standards in place.
UDP also looks the way to go. Everything is permanently listening to
everything else, but only the master controller sends out polling
messages dictating which slaves will 'speak'. To me, this keeps the
protocol as simple, fast and flexible as possible and should completely
avoid collisions. It would seem other people have come to a similar
conclusion.
As we are working FOSS, everything is open for scrutiny and later
development of the messaging system is not a great hardship. Practical
experience can dictate what *really* is good and what isn't.
A little bit of sad news.
I decided to fire up my ancient valve voltmeter, notch filters etc. and
have a look at the distortion products from a mathematically generated
1kHz sinewave spat out by my 2496 sound card, just to give some form of
reference. Unfortunately the meter has gone to that great repair shop in
the sky :(
So...
My immediate project is now to build myself a battery operated digital
AC millviltmeter with true RMS volts and dB scaling based around Analog
Devices AD636.
Parts are on order :D
--
Will J Godfrey
http://www.musically.me.uk
Say you have a poem and I have a tune.
Exchange them and we can both have a poem, a tune, and a song.
