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Diffstat (limited to 'src/powerlist.cc')
-rw-r--r-- | src/powerlist.cc | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/src/powerlist.cc b/src/powerlist.cc new file mode 100644 index 0000000..a298927 --- /dev/null +++ b/src/powerlist.cc @@ -0,0 +1,219 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/*************************************************************************** + * powerlist.cc + * + * Sun Jul 28 19:45:48 CEST 2013 + * Copyright 2013 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 "powerlist.h" + +#include <stdlib.h> +#include <math.h> +#include <string.h> + +#include <hugin.hpp> + +#define SIZE 500 + +// Box–Muller transform. +// See: http://en.wikipedia.org/wiki/Box%E2%80%93Muller_transform +float box_muller_transform(float mean, float stddev) +{ + float U1 = (float)rand() / (float)RAND_MAX; + float U2 = (float)rand() / (float)RAND_MAX; + + float x = sqrt(-2.0 * log(U1)) * cos(2.0 * M_PI * U2); + + return mean + stddev * x; +} + +PowerList::PowerList() +{ + power_max = 0; +} + +#define THRES 1.0 + +void PowerList::add(Sample *sample) +{ + PowerListItem item; + item.power = -1; + item.sample = sample; + + samples.push_back(item); +} + +Channel *PowerList::getMasterChannel() +{ + std::map<Channel *, int> count; + + std::vector<PowerListItem>::iterator si = samples.begin(); + while(si != samples.end()) { + PowerListItem &item = *si; + Sample *sample = item.sample; + + Channel *max_channel = NULL; + sample_t max_val = 0; + + // DEBUG(rand, "Sample: %s\n", sample->name.c_str()); + + size_t ci = 0; + AudioFiles::iterator ai = sample->audiofiles.begin(); + while(ai != sample->audiofiles.end()) { + Channel *c = ai->first; + AudioFile *af = ai->second; + + af->load(SIZE); + + float silence = 0; + size_t silence_length = 4; + for(size_t s = af->size; s > 0 && s > af->size - silence_length; s--) { + silence += af->data[s]; + } + silence /= silence_length; + + size_t s = 0; + for(; s < af->size; s++) { + float val = af->data[s] * af->data[s] * (1.0 / (float)(s+1)); + if(val > max_val) { + max_val = val; + max_channel = c; + break; + } + } + + af->unload(); + + ai++; + ci++; + } + + if(max_channel) { + if(count.find(max_channel) == count.end()) count[max_channel] = 0; + count[max_channel]++; + } + + si++; + } + + Channel *master = NULL; + int max_count = -1; + + std::map<Channel *, int>::iterator ci = count.begin(); + while(ci != count.end()) { + if(ci->second > max_count && + strstr(ci->first->name.c_str(), "Alesis") == 0) { + master = ci->first; + max_count = ci->second; + } + ci++; + } + + return master; +} + +void PowerList::finalise() +{ + Channel *master_channel = getMasterChannel(); + + if(master_channel == NULL) { + ERR(rand, "No master channel found!\n"); + return; // This should not happen... + } + + DEBUG(rand, "Master channel: %s\n", master_channel->name.c_str()); + + std::vector<PowerListItem>::iterator si = samples.begin(); + while(si != samples.end()) { + PowerListItem &item = *si; + Sample *sample = item.sample; + + DEBUG(rand, "Sample: %s\n", sample->name.c_str()); + + AudioFile *master = NULL; + + AudioFiles::iterator afi = sample->audiofiles.begin(); + while(afi != sample->audiofiles.end()) { + if(afi->first->name == master_channel->name) { + master = afi->second; + break; + } + afi++; + } + + if(master == NULL) { + si++; + continue; + } + + master->load(); + + float power = 0; + size_t s = 0; + for(; s < SIZE && s < master->size; s++) { + power += master->data[s] * master->data[s]; + } + + power = sqrt(power); + + if(power > power_max) power_max = power; + + item.power = power; + + DEBUG(rand, " - power: %f\n", power); + + si++; + } +} + +Sample *PowerList::get(level_t level) +{ + Sample *sample = NULL; + float power = 0; + + float mean = level * power_max; + float stddev = power_max / samples.size() * 2; + + float lvl = box_muller_transform(mean, stddev); + + DEBUG(rand, "lvl: %f (mean: %.2f, stddev: %.2f)\n", + lvl, mean, stddev); + + std::vector<PowerListItem>::iterator i = samples.begin(); + while(i != samples.end()) { + if(sample == NULL) { + sample = i->sample; + power = i->power; + } + + if(fabs(i->power - lvl) < fabs(power - lvl)) { + sample = i->sample; + power = i->power; + } + + i++; + } + + DEBUG(rand, "Found power %f\n", power); + + return sample; +} |