summaryrefslogtreecommitdiff
path: root/gtk2_ardour/fft_result.cc
blob: b4a82c25869e20443d6b285f7fbde1fee2481772 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
/*
 * Copyright (C) 2006, 2016 Paul Davis
 * Written by Sampo Savolainen & Robin Gareus
 *
 * This program 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.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

#include "fft_result.h"
#include "fft_graph.h"
#include <cstdlib>
#include <cstring>
#include <string>
#include <cmath>
#include <algorithm>

using namespace std;

FFTResult::FFTResult(FFTGraph *graph, Gdk::Color color, string trackname)
{
	_graph = graph;

	_windowSize = _graph->windowSize();
	_dataSize   = _windowSize / 2;
	_averages = 0;
	_min_flat = _max_flat = 0.0;
	_min_prop = _max_prop = 0.0;

	_data_flat_avg = (float *) malloc (sizeof(float) * _dataSize);
	_data_flat_min = (float *) malloc (sizeof(float) * _dataSize);
	_data_flat_max = (float *) malloc (sizeof(float) * _dataSize);
	_data_prop_avg = (float *) malloc (sizeof(float) * _dataSize);
	_data_prop_min = (float *) malloc (sizeof(float) * _dataSize);
	_data_prop_max = (float *) malloc (sizeof(float) * _dataSize);

	for (unsigned int i = 0; i < _dataSize; i++) {
		_data_flat_min[i] = FLT_MAX;
		_data_flat_max[i] = FLT_MIN;
		_data_flat_avg[i] = 0;
		_data_prop_min[i] = FLT_MAX;
		_data_prop_max[i] = FLT_MIN;
		_data_prop_avg[i] = 0;
	}

	_color     = color;
	_trackname = trackname;
}

void
FFTResult::analyzeWindow(float *window)
{
	float const * const _hanning = _graph->_hanning;
	float *_in = _graph->_in;
	float *_out = _graph->_out;

	// Copy the data and apply the hanning window
	for (unsigned int i = 0; i < _windowSize; ++i) {
		_in[i] = window[i] * _hanning[i];
	}

	fftwf_execute(_graph->_plan);

	// calculate signal power per bin
	float b = _out[0] * _out[0];

	_data_flat_avg[0] += b;
	if (b < _data_flat_min[0]) _data_flat_min[0] = b;
	if (b > _data_flat_max[0]) _data_flat_max[0] = b;

	for (unsigned int i = 1; i < _dataSize - 1; ++i) {
		b = (_out[i] * _out[i]) + (_out[_windowSize - i] * _out[_windowSize - i]);
		_data_flat_avg[i] += b;
		if (_data_flat_min[i] > b)  _data_flat_min[i] = b;
		if (_data_flat_max[i] < b ) _data_flat_max[i] = b;
	}

	_averages++;
}

void
FFTResult::finalize()
{
	if (_averages == 0) {
		_min_flat = _max_flat = 0.0;
		_min_prop = _max_prop = 0.0;
		return;
	}

	// Average & scale
	for (unsigned int i = 0; i < _dataSize - 1; ++i) {
		_data_flat_avg[i] /= _averages;
		// proportional, pink spectrum @ -18dB
		_data_prop_avg[i] = _data_flat_avg [i] * i / 63.096f;
		_data_prop_min[i] = _data_flat_min [i] * i / 63.096f;
		_data_prop_max[i] = _data_flat_max [i] * i / 63.096f;
	}

	_data_prop_avg[0] = _data_flat_avg [0] / 63.096f;
	_data_prop_min[0] = _data_flat_min [0] / 63.096f;
	_data_prop_max[0] = _data_flat_max [0] / 63.096f;

	// calculate power
	for (unsigned int i = 0; i < _dataSize - 1; ++i) {
		_data_flat_min[i] = power_to_db (_data_flat_min[i]);
		_data_flat_max[i] = power_to_db (_data_flat_max[i]);
		_data_flat_avg[i] = power_to_db (_data_flat_avg[i]);
		_data_prop_min[i] = power_to_db (_data_prop_min[i]);
		_data_prop_max[i] = power_to_db (_data_prop_max[i]);
		_data_prop_avg[i] = power_to_db (_data_prop_avg[i]);
	}

	// find min & max
	_min_flat = _max_flat = _data_flat_avg[0];
	_min_prop = _max_prop = _data_prop_avg[0];

	for (unsigned int i = 1; i < _dataSize - 1; ++i) {
		_min_flat = std::min (_min_flat, _data_flat_avg[i]);
		_max_flat = std::max (_max_flat, _data_flat_avg[i]);
		_min_prop = std::min (_min_prop, _data_prop_avg[i]);
		_max_prop = std::max (_max_prop, _data_prop_avg[i]);
	}

	_averages = 0;
}

FFTResult::~FFTResult()
{
	free(_data_flat_avg);
	free(_data_flat_min);
	free(_data_flat_max);
	free(_data_prop_avg);
	free(_data_prop_min);
	free(_data_prop_max);
}