Linux-audio-dev

linux-audio-dev@lists.linuxaudio.org

3 participants
7448 discussions

jack transport change accuracy for looping

by Iain Duncan

Just wondering if I understand this correctly. I making a loop based app for step sequencing. When I previously did this in Csound, I clocked it off a phasor, so the timing was sample accurate ( but that brought all it's own issues to be sure ). I'm wondering whether I should do the same thing in jack app, or use the jack transport clock, or some hybrid. My question, am I correct in understanding that if I use the jack transport position to rewind in time, I'll get: C) any other clients with running audio looping back to ( may or may not be desirable ) B) a jitter based on the amount of time left between when the loop should end and the end of the frame buffer in which the loop length runs out? Has anyone solved B? Could it be done by some complex tempo cheating trick? Does anyone have any methods they've used for tight timing of looping in a jack app? Pointers at code appreciated of course. =) thank! Iain

12 years, 10 months

Re: [LAD] tutorial or example for using jack ring buffer between threads?

by harryhaaren＠gmail.com

On , Iain Duncan <iainduncanlists(a)gmail.com> wrote: > Thanks! Did you just write it? Yup. As in literally just there. And I was reading your post in the new RAUL thread as you were typing that :D All the best, -Harry

12 years, 10 months

Fw: Re: "bleeding edge html5" has interesting Audio APIs

by Fons Adriaensen

On Tue, Nov 22, 2011 at 09:13:37PM +0100, Nick Copeland wrote: > If you are using a toolkit that has a data flow of the following: > > pointer motion->graphical display->values->application->output > > Well, basically that is broken as you have a flow that is > > input->output->input->application->output > > invariably that is going to lead to issues. The tail (the toolkit) is wagging the dog > (the application) as it imposes restrictions on the values the application is allowed > to see. > > In my opinion (ok, it is only opinion) is that the correct flow is > > input->application->output Yes, I see your point, and it makes a lot of sense. So what would be required is * compute the new parameter value from - a stored state in 'paramater space' rather than 'widget space' - and pointer (mouse) gestures, * update the widget according to that value. This is more or less what I do in the rotary controls used in e.g. zita-at1 and zita-rev1. It's possible because the mouse movement and the visual representation of the value (the angle of the line on the rotary knob) are not directly related anyway. But this is not how most (all) toolkits work. You could probably use them in the way you suggest with some extra effort. But in many cases (e.g. linear sliders) the pointer and widget would have to remain in sync visually, which then means that your resolution in paramater space can't be better than the visual one. Unless you allow the pointer to move faster than the visual object it is controlling (which is what I do in the 2-D panner, but it's possible only because the widget is so small). Ciao, -- FA Vor uns liegt ein weites Tal, die Sonne scheint - ein Glitzerstrahl.

12 years, 10 months

help compiling Aliki

by federico lopez

Hi, I am trying to compile Aliki 0.1 in Ubuntu 10.10 I Installed the required libraries libclthreads (>= 2.4.0) and libclxclient (>= 3.6.1) and libclalsadrv (>= 2.0.0). but when I try to compile I get this error: In file included from aliki.cc:26: styles.h:26: fatal error: clxclient.h: No such file or directory compilation terminated. Note: I found and fixed a problem installing libclxclient, but maybe I broke something... when I tried to install clxclient show this error: In file included from xdisplay.cc:22: clxclient.h:31: fatal error: X11/Xft/Xft.h: No such file or directory compilation terminated. I found a solution in a website and was solved with: |sudo apt-get install libxft-dev| thanks, federico lopez

12 years, 10 months

"bleeding edge html5" has interesting Audio APIs

by Niels Mayer

http://kinlan-presentations.appspot.com/bleeding/index.html#42 ............ Don't we already have HTML5 <audio>? Yes :)...but <audio> can only take us so far Simple low-latency, glitch-free, audio playback and scheduling Real-time processing and analysis Low-level audio manipulation Effects: spatial panning, low/high pass filters, convolution, gain, ... ........... Judging by all the google-chrome symbols, this appears to be google-chrome-specific. Is any of this FOSS and available in Chromium? -- Niels http://nielsmayer.com

12 years, 10 months

jack position/timebase tutorial/starting points?

by Iain Duncan

Just because everyone's tips here were so helpful for the ringbuffer conversation, does anyone have any pointers for where to start understanding jack transport and clocking, other than the transport client example? thanks! Iain

12 years, 10 months

RAUL or other libraries for real this time? ;-)

by Iain Duncan

Still curious about RAUL. As i have no immediate plans beyond learning how to write proper audio app, even if license restrictions prevent from using RAUL in a hypothetical commercial product years down the road, it may well be worth me using for my own personal needs in the meantime. Would love to hear feedback on technical merits of RAUL, minus license conversations which now have my other thread. ;-) heck I'd like to hear about any other libraries worth looking into too. I'm trending at the moment to STK, embedded csound, Jack, and QT for gui. The part I need library help with is likely synchronization and interprocess/interthread communication. ( ie do I use the jack ringbuffer? Do I look at boost queue implementations? does RAUL have a higher level convenience ring buffer? thanks! iain

12 years, 10 months

RAUL?

by Iain Duncan

I found it on Dave's site, but other than that, couldn't find find much mention of it. Do many people use it? Would it be wise to dig into RAUL for writing a real time jack app? Dave, any comments on it? http://drobilla.net/software/raul/ thanks iain

12 years, 10 months

tutorial or example for using jack ring buffer between threads?

by Iain Duncan

Can anyone point me at what they consider the best thing to look at for an introduction to communication between threads in a jack app using the ringbuffer? I found some, but as docs appear a bit scattered, wondered if there was a known best-first-reference type thing. thanks iain

12 years, 10 months

[ANN] ALPHA: jiss - Jack Interactice Sequencing Software

by Florian Paul Schmidt

this is totally prealpha-OMG-IT'S-FULL-OFF-FAIL-state.. https://github.com/fps/jiss requirements: SWIG, libjack-dev and liblua5.1-dev on ubuntu.. compile with make (if it fails, you're on your own. it's a simple makefile though). then run in the build dir: lua wicked.lua if you have jass running with a piano sample on midi channel 0, a bass drum on channel 1 and a hihat on 2 you should get a rather weird interpretation of "stella by starlight", a jazz standard.. something like this (some effects added with jack-rack): http://shirkhan.dyndns.org/~tapas/stella.ogg (wicked.lua code here with some omission of some chords at the start and some remarks in comments added): -- some stuff :D require "jiss" require "jissing" -- create engine in stopped state e = jiss.engine() -- setup some state that the sequences later use -- e:run can only be used when the engine is stopped.. -- as this is executed in non-RT context it's ok to -- create some variables and tables here.. e:run([[ bar = 0; min = 20; max = 80; stella = { range(min, 80, min7b5(E(4))), range(min, 80, min7b5(E(4))), -- cut away quite a bit here (see wicked.lua in git clone) :D range(min, 80, maj7s11(B(4)-1)), range(min, 80, maj7s11(B(4)-1)) } ]]) -- this sequence can control the others since it's processed before -- the others in the engine -- events string is newline sensitive. in this case the events -- on consecutive lines are spaced 1 second apart.. -- also: loop back to 0 at time t = 8 sec tune = seq(e, "tune", loop_events(8, events_string(1, [[ drums1:relocate(0.0); drums1:start_(); notes:relocate(0.0); notes:start_() drums1:stop_(); ]]))) -- manually start this sequence and add to the engine tune:start() -- note that a copy is appended to the engine e:append(tune) -- a sequence that controls the global variable bar to advance through the song play(e, seq(e, "control", loop_events(1, events_string(1, [[ bar = bar + 1; bar = (bar % #stella); ]])))) -- events at fixed times. loop at t = 0.75 sec play(e, seq(e, "notes", loop_events(0.75, { { 0.125, [[ for i = 1,4 do note_on(0, 24 + stella[bar][math.random(#stella[bar])], 30 + math.random()*64) end ]] }, { 0.5, [[ for i = 1,2 do note_on(0, 24 + stella[bar][math.random(#stella[bar])], 10 + math.random()*34) end ]] } }))) -- a drum pattern drums = [[ note_on(1, 64, 127); note_on(2, 64, 127) note_on(2, 64, 127) note_on(2, 64, math.random(127)) note_on(2, 64, math.random(127)) note_on(2, 42, 110) note_on(2, 64, 127) note_on(2, 64, math.random(127)) note_on(1, 64, 127); note_on(2, 64, 127) note_on(2, 64, math.random(127)) ]] play(e, seq(e, "drums1", loop_events(1, events_string(0.125/2, drums)))) -- connect all sequence outputs to jass:in connect(e,"jass:in") -- run the whole thing e:start() -- wait for the user to press enter io.stdin:read'*l' Have fun, Flo

12 years, 10 months

Jump to page:

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

Linux-audio-dev