- chuck-users - lists.cs.princeton.edu

a few language questions
by Michael Heuer 15 Nov '07

15 Nov '07

Hello, I have a few chuck language questions: Is it possible to define a "growing" array? The associative portion of the array grows without bounds but I can't see how to do that with the indexed portion. Object @ list[]; for (0 => int i; i < 100; i++) { Object o @=> list[i]; } Is it possible to check a reference against null? Object @ list[100]; 0 => int size; for (0 => int i; i < list.cap(); i++) { if (list[i] is null?) { size++; } } Is there a "String toString()" or similar method on Object? I wish to override "Expressions which represent an object will print the value of that object's reference address". Do reflective methods exist on the base Object type (its "Class")? e.g. Function[] getFunctions(); ... Thanks, michael

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MAUI logic question...
by Jascha Narveson 14 Nov '07

14 Nov '07

Ahoy, ChucKists - I've just coded myself a perfectly serviceable metronome, and it works fine except for a small nagging thing in the MAUI. In my metronome, I have 2 toggle type buttons, "thirds" and "sixteenths". If one is on, the other is off, so i'm always subdividing the pulse one way or the other. As it is, if I turn "thirds" on and off, the "sixteenth" button dutifully goes off and on in a complementary way. If I do this, though: - toggle "thirds" on ("quarters" stays off) - toggle "quarters" on ("thirds" politely turns off) - toggle "thirds" on At this point they're *both* on. I can get back to a one-or-the- other state by fussing around and toggling the right combo of things, but i'd rather not do that. I've attached just the button-related code below - i've got two functions set up that are turning the other button on or off depending on whether or not they're off or on. It's bending my brain a bit to figure out why it sometimes behaves the way it does - any insights out there? thanks, as always, j. ------code------ MAUI_View view; view.size(400,200); MAUI_Button thirds; thirds.toggleType(); thirds.size(110,110); thirds.position(0, 100); thirds.name("thirds"); view.addElement(thirds); MAUI_Button sixteenths; sixteenths.toggleType(); sixteenths.size(110,110); sixteenths.position(110, 100); sixteenths.name("sixteenths"); view.addElement(sixteenths); view.display(); fun void controlThirds() { while (true) { thirds => now; sixteenths.state(0); <<<"thirds on">>>; thirds => now; sixteenths.state(1); <<<"thirds off">>>; } } fun void controlSixteenths() { while (true) { sixteenths => now; thirds.state(0); <<<"sixteenths on">>>; sixteenths => now; thirds.state(1); <<<"sixteenths off">>>; } } spork ~ controlThirds(); spork ~ controlSixteenths(); while (true) { 1::second => now; }

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fft issues
by eduard aylon 14 Nov '07

14 Nov '07

Hello list, some time ago I reported the following as a possible bug on the wiki: * Assigining window to ifft seems to yield "poorer" results than not assigning it. Try it in /examples/win.ck and you'll notice a rougher (faster beating) sound. (eduard) However, looking again at the code of win.ck I realised the size of the window was set to the half of fft_size. Unless zero-padding is performed, shouldn't window_size and fft_size be the same? Anyway, setting the window size to fft_size (both for forward fft and iverse fft) yields correct results in examples/win.ck. This applies to some of my previous emails where brick wall filters and vocoder were discussed. That is, window_size should be set to fft_size and resulting spectrum to fft_size/2. But now I am also concerned about the size of the spectrum. In chuck this is FFT_SIZE/2, but shouldn't it be FFT_SIZE/2+1 or does the first value in spectrum hold both DC and Nyquist components? By the way, could chuck perform zero-padding when window_size < fft_size? eduard

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Phoneme Recognition with ChucK
by Inventor-66＠comcast.net 14 Nov '07

14 Nov '07

Hi, On the electro-music.com forum we've been discussing a phoneme recognizer based on ChucK. So far we have an FFT grabber that gets its samples off the dac so you can ChucK-up any input file to it including a microphone listener, rec_in.ck, a little bit of feature extraction and a rules-based phoneme recognizer. It can basically tell an "ee" phoneme from an "ay" phoneme, and I plan to add all the vowels, a e i o u really soon. To help with the project, I was wondering if anyone from the list would like to contribute some suggestions or comments about our technique. Basically we are shunning the hidden markov models that are often used to recognize words from phonemes in favor of creating a simple phoneme recognizer. This way we offload much of the computation from the machine into the human user's brain, thus enabling a compact ChucK implementation as well as someday a simple dsPIC processor-based handheld product that streams text from a mic for the hearing impaired. For example, if you said "Mary had a little lamb", the device might output "mehry hahd ah letl lam" and it is up to the user to interpret that into regular speech. In this way a very compact little product with just a few chips could be produced that would retail for twenty dollars or lower, making it affordable and portable for the hearing impaired to use. I was Just curious as to what your thoughts may be, I'm doing the code and Kassen plus others like dewdrop_world are commenting and pointing me in the right direction as we go. Please feel free to offer suggestions and/or constructive criticism. Thanks, Les

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'if' statement parse error...?
by Jascha Narveson 13 Nov '07

13 Nov '07

I'm getting a parse error on an 'if' statement, but I feel like it should work - in fact, i have perfectly fine 'if' statements elsewhere in a larger piece of code i'm working on which work exactly the way i'd expect them to. For some reason, though, an innocent looking 'if' statement in a different part of my code won't compile. To test if i wasn't just missing something, i carefully typed out a simple 'if' in a fresh document, after rebooting the program. Does anyone else get a parse error when running this simple simple thing in miniAudicle? thanks, j ---code---- while (true) { Std.rand2(1,6) => int i; <<<i>>>; if (i > 3) {<<<"true">>>} else {<<<"false">>>}; 1::second => now; }

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miniaudicle no sound on gutsy
by jim 13 Nov '07

13 Nov '07

Hi I've compiled miniaudicle 0.1.3.8 on ubuntu gutsy with alsa. Using the simple code SinOsc s => dac;2::second=>now; doesn't output anything. But it works using chuck in command line. What's the problem? Thnaks

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wiimote=>chuck on linux
by Graham Percival 13 Nov '07

13 Nov '07

Hi all, I'm trying to get input from a wii controller into ChucK. One option is to use OSX+darwiinOSC to send OSC messages to chuck, but this requires OSX. There are a number of wii libraries for Linux; does anybody know if they can communicate directly with ChucK's hid input? So far I haven't been able to find a linux wii driver that sends OSC messages. Cheers, - Graham

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Time logic
by Juan-Pablo Caceres 11 Nov '07

11 Nov '07

Hi there, I have another question concerning time logic. The following 2 examples are similar: // 1) while (true) { <<<"HELLO">>>; 1::second => now; } // 2) while (1::second => now) { <<<"HELLO">>>; } So the question is, is the second case using some syntactic sugar? Because conceptually it doesn't sound right to me. Maybe the chuck gurus out there can make more sense of it? Thanks! JPa.

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recording Chuck output once sound has started
by Jascha Narveson 11 Nov '07

11 Nov '07

How do people like to record audio from ChucK once it has already started running? I was just playing with an interesting audio- processing patch and wanted to record the output, and thought maybe routing ChucK through Jack would work, but i didn't have any luck with that. cheers, jascha

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mouse up/down controlling signal path
by Jascha Narveson 11 Nov '07

11 Nov '07

hello again, chuckists - I'd like to alter signal flow in response to input from HID devices. In this small example, i want mouse down to result in reverb, and mouse up to result in dry signal. The problem is that the reverb persists after the first mouse down - i tried unchucking in the mouse up "else if" statement, but that didn't work... thanks, all, j ----code---- adc => dac; NRev rev; Hid hi; HidMsg msg; if( !hi.openMouse( 0 ) ) me.exit(); <<< "mouse '" + hi.name() + "' ready...", "" >>>; while( true ) { // wait on event hi => now; // loop over messages while( hi.recv( msg ) ) { if( msg.isButtonDown() ) { <<<"down">>>; adc => rev => dac; } else if( msg.isButtonUp() ) { <<<"up">>>; adc => dac; } } }

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