From ef523065eb5e9535d0bd4b3ede820a231e547930 Mon Sep 17 00:00:00 2001 From: deva Date: Fri, 25 Jul 2008 11:28:27 +0000 Subject: First primitive beatdetection in place. --- src/beatmapper.cc | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100644 src/beatmapper.cc (limited to 'src/beatmapper.cc') diff --git a/src/beatmapper.cc b/src/beatmapper.cc new file mode 100644 index 0000000..6a7e35a --- /dev/null +++ b/src/beatmapper.cc @@ -0,0 +1,70 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/*************************************************************************** + * beatmapper.cc + * + * Fri Jul 25 11:17:42 CEST 2008 + * Copyright 2008 Bent Bisballe Nyeng + * deva@aasimon.org + ****************************************************************************/ + +/* + * This file is part of DrumGizmo. + * + * DrumGizmo is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * DrumGizmo is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with DrumGizmo; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + */ +#include "beatmapper.h" + +BeatMapper::BeatMapper(Instrument *instrument) +{ + this->instrument = instrument; + for(size_t i = 0; i < HISTORY_SIZE; i++) hist[i] = 0.0; + C = 1.3; + mindist = 2; + last = mindist; +} + + +Sample *BeatMapper::map(jack_nframes_t nframes) +{ + Sample *sample = NULL; + + jack_default_audio_sample_t *buffer; + buffer = (jack_default_audio_sample_t *)jack_port_get_buffer(instrument->port, nframes); + + float e = 0.0; + for(size_t i = 0; i < nframes; i++) { + e += buffer[i] * buffer[i]; + // buffer[i] = 0.0; + } + + float E = 0.0; + for(size_t i = 0; i < HISTORY_SIZE; i++) E += hist[i] / (float)HISTORY_SIZE; + + printf("last: %d, E: %f, e: %f - threshold: %f\n", last, E, e, 1.3 * E); + + // Shift history and save new value + for(size_t i = 0; i < HISTORY_SIZE - 1; i++) hist[i] = hist[i+1]; + hist[HISTORY_SIZE - 1] = e; + + if(e > C * E && last > mindist) { + Velocity *v = instrument->getVelocity(127); + if(v) sample = v->getSample(); + } + + last++; + if(sample) last = 0; + + return sample; +} -- cgit v1.2.3