Mike Sheldon
/
Synth
A simple string synthesizer implementing the Karplus-Strong algorithm. Licensed under the GNU LGPL.
Synth.cpp@0:ce6724069f0a, 2013-01-09 (annotated)
- Committer:
- elleo
- Date:
- Wed Jan 09 22:46:12 2013 +0000
- Revision:
- 0:ce6724069f0a
Migration to new repository
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
elleo | 0:ce6724069f0a | 1 | /* |
elleo | 0:ce6724069f0a | 2 | * libmbed-synth An audio synthesis library capable of running |
elleo | 0:ce6724069f0a | 3 | * alongside other activities. |
elleo | 0:ce6724069f0a | 4 | * Copyright (C) <2009> Michael Sheldon <mike@mikeasoft.com> |
elleo | 0:ce6724069f0a | 5 | * |
elleo | 0:ce6724069f0a | 6 | * This library is free software; you can redistribute it and/or |
elleo | 0:ce6724069f0a | 7 | * modify it under the terms of the GNU Library General Public |
elleo | 0:ce6724069f0a | 8 | * License as published by the Free Software Foundation; either |
elleo | 0:ce6724069f0a | 9 | * version 2 of the License, or (at your option) any later version. |
elleo | 0:ce6724069f0a | 10 | * |
elleo | 0:ce6724069f0a | 11 | * This library is distributed in the hope that it will be useful, |
elleo | 0:ce6724069f0a | 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
elleo | 0:ce6724069f0a | 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
elleo | 0:ce6724069f0a | 14 | * Library General Public License for more details. |
elleo | 0:ce6724069f0a | 15 | * |
elleo | 0:ce6724069f0a | 16 | * You should have received a copy of the GNU Library General Public |
elleo | 0:ce6724069f0a | 17 | * License along with this library; if not, write to the |
elleo | 0:ce6724069f0a | 18 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
elleo | 0:ce6724069f0a | 19 | * Boston, MA 02111-1307, USA. |
elleo | 0:ce6724069f0a | 20 | */ |
elleo | 0:ce6724069f0a | 21 | |
elleo | 0:ce6724069f0a | 22 | #include "Synth.h" |
elleo | 0:ce6724069f0a | 23 | |
elleo | 0:ce6724069f0a | 24 | Synth::Synth(PinName aout) : |
elleo | 0:ce6724069f0a | 25 | _aout(aout) { |
elleo | 0:ce6724069f0a | 26 | _repeat = false; |
elleo | 0:ce6724069f0a | 27 | _samplerate = 22000; |
elleo | 0:ce6724069f0a | 28 | _samples = NULL; |
elleo | 0:ce6724069f0a | 29 | _sample_size = 0; |
elleo | 0:ce6724069f0a | 30 | _position = 0; |
elleo | 0:ce6724069f0a | 31 | _bpm = 120; |
elleo | 0:ce6724069f0a | 32 | _notes = NULL; |
elleo | 0:ce6724069f0a | 33 | _num_notes = 0; |
elleo | 0:ce6724069f0a | 34 | } |
elleo | 0:ce6724069f0a | 35 | |
elleo | 0:ce6724069f0a | 36 | void Synth::play() { |
elleo | 0:ce6724069f0a | 37 | _ticker.attach(this, &Synth::_proc_sample, 1.0 / _samplerate); |
elleo | 0:ce6724069f0a | 38 | |
elleo | 0:ce6724069f0a | 39 | DigitalOut l(LED1); |
elleo | 0:ce6724069f0a | 40 | l = 1; |
elleo | 0:ce6724069f0a | 41 | } |
elleo | 0:ce6724069f0a | 42 | |
elleo | 0:ce6724069f0a | 43 | void Synth::pause() { |
elleo | 0:ce6724069f0a | 44 | _ticker.detach(); |
elleo | 0:ce6724069f0a | 45 | } |
elleo | 0:ce6724069f0a | 46 | |
elleo | 0:ce6724069f0a | 47 | void Synth::stop() { |
elleo | 0:ce6724069f0a | 48 | _position = 0; |
elleo | 0:ce6724069f0a | 49 | _ticker.detach(); |
elleo | 0:ce6724069f0a | 50 | } |
elleo | 0:ce6724069f0a | 51 | |
elleo | 0:ce6724069f0a | 52 | void Synth::set_repeat(bool repeat) { |
elleo | 0:ce6724069f0a | 53 | _repeat = repeat; |
elleo | 0:ce6724069f0a | 54 | } |
elleo | 0:ce6724069f0a | 55 | |
elleo | 0:ce6724069f0a | 56 | void Synth::set_instrument(PluckedGuitar *instrument){ |
elleo | 0:ce6724069f0a | 57 | _instrument = instrument; |
elleo | 0:ce6724069f0a | 58 | _instrument->set_bpm(_bpm); |
elleo | 0:ce6724069f0a | 59 | _instrument->set_samplerate(_samplerate); |
elleo | 0:ce6724069f0a | 60 | } |
elleo | 0:ce6724069f0a | 61 | |
elleo | 0:ce6724069f0a | 62 | void Synth::set_bpm(int bpm) { |
elleo | 0:ce6724069f0a | 63 | _bpm = bpm; |
elleo | 0:ce6724069f0a | 64 | if(_instrument != NULL) { |
elleo | 0:ce6724069f0a | 65 | _instrument->set_bpm(_bpm); |
elleo | 0:ce6724069f0a | 66 | } |
elleo | 0:ce6724069f0a | 67 | } |
elleo | 0:ce6724069f0a | 68 | |
elleo | 0:ce6724069f0a | 69 | void Synth::_proc_sample() { |
elleo | 0:ce6724069f0a | 70 | if (_position == 0) { |
elleo | 0:ce6724069f0a | 71 | _instrument->note(_notes[_position]); |
elleo | 0:ce6724069f0a | 72 | _position++; |
elleo | 0:ce6724069f0a | 73 | } |
elleo | 0:ce6724069f0a | 74 | |
elleo | 0:ce6724069f0a | 75 | float sample = _instrument->proc_sample(); |
elleo | 0:ce6724069f0a | 76 | |
elleo | 0:ce6724069f0a | 77 | if (sample == -1) { |
elleo | 0:ce6724069f0a | 78 | _instrument->note(_notes[_position]); |
elleo | 0:ce6724069f0a | 79 | _position++; |
elleo | 0:ce6724069f0a | 80 | } else { |
elleo | 0:ce6724069f0a | 81 | _aout = sample; |
elleo | 0:ce6724069f0a | 82 | } |
elleo | 0:ce6724069f0a | 83 | |
elleo | 0:ce6724069f0a | 84 | if (sample == -1 && _position > _num_notes) { |
elleo | 0:ce6724069f0a | 85 | if(_repeat) { |
elleo | 0:ce6724069f0a | 86 | _position = 0; |
elleo | 0:ce6724069f0a | 87 | } else { |
elleo | 0:ce6724069f0a | 88 | stop(); |
elleo | 0:ce6724069f0a | 89 | } |
elleo | 0:ce6724069f0a | 90 | } |
elleo | 0:ce6724069f0a | 91 | } |
elleo | 0:ce6724069f0a | 92 | |
elleo | 0:ce6724069f0a | 93 | void Synth::add_note(float frequency, float duration) { |
elleo | 0:ce6724069f0a | 94 | _num_notes++; |
elleo | 0:ce6724069f0a | 95 | Note n; |
elleo | 0:ce6724069f0a | 96 | n.frequency = frequency; |
elleo | 0:ce6724069f0a | 97 | n.duration = duration; |
elleo | 0:ce6724069f0a | 98 | if (_notes == NULL) { |
elleo | 0:ce6724069f0a | 99 | _notes = (Note*) malloc(sizeof(Note)); |
elleo | 0:ce6724069f0a | 100 | } else { |
elleo | 0:ce6724069f0a | 101 | _notes = (Note*) realloc(_notes, sizeof(Note) * _num_notes); |
elleo | 0:ce6724069f0a | 102 | |
elleo | 0:ce6724069f0a | 103 | } |
elleo | 0:ce6724069f0a | 104 | _notes[_num_notes - 1] = n; |
elleo | 0:ce6724069f0a | 105 | } |