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
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
|
/* Copyright (C) 2010-2020 The RetroArch team
*
* ---------------------------------------------------------------------------------------
* The following license statement only applies to this file (vibrato.c).
* ---------------------------------------------------------------------------------------
*
* Permission is hereby granted, free of charge,
* to any person obtaining a copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <math.h>
#include <stdlib.h>
#include <string.h>
#include <retro_miscellaneous.h>
#include <libretro_dspfilter.h>
#include <string/stdstring.h>
#define sqr(a) ((a) * (a))
#define VIBRATO_BASE_DELAY_SEC 0.002f /* 2 ms */
#define VIBRATO_FREQUENCY_DEFAULT_HZ 2.0f
#define VIBRATO_FREQUENCY_MAX_HZ 14.0f
#define VIBRATO_DEPTH_DEFAULT_PERCENT 50.0f
#define VIBRATO_ADD_DELAY 3
static float hermite_interp(float x, float *y)
{
float c0 = y[1];
float c1 = (1.0f / 2.0f) * (y[2] - y[0]);
float c2 = (y[0] - (5.0f / 2.0f) * y[1]) + (2.0f * y[2] - (1.0f / 2.0f) * y[3]);
float c3 = (1.0f / 2.0f) * (y[3] - y[0]) + (3.0f / 2.0f) * (y[1] - y[2]);
return ((c3 * x + c2) * x + c1) * x + c0;
}
struct vibrato_core
{
float* buffer;
float freq;
float samplerate;
float depth;
int phase;
int writeindex;
int size;
};
struct vibrato
{
struct vibrato_core left, right;
};
static void vibrato_free(void *data)
{
struct vibrato *vib = (struct vibrato*)data;
free(vib->left.buffer);
free(vib->right.buffer);
free(data);
}
static void vibratocore_init(struct vibrato_core *core,float depth,int samplerate,float freq)
{
core->size = VIBRATO_BASE_DELAY_SEC * samplerate * 2;
core->buffer = malloc((core->size + VIBRATO_ADD_DELAY) * sizeof(float));
memset(core->buffer, 0, (core->size + VIBRATO_ADD_DELAY) * sizeof(float));
core->samplerate = samplerate;
core->freq = freq;
core->depth = depth;
core->phase = 0;
core->writeindex = 0;
}
float vibratocore_core(struct vibrato_core *core,float in)
{
int ipart;
float delay, readindex, fpart, value;
float M = core->freq / core->samplerate;
int maxphase = core->samplerate / core->freq;
float lfo = sin(M * 2. * M_PI * core->phase++);
int maxdelay = VIBRATO_BASE_DELAY_SEC * core->samplerate;
core->phase = core->phase % maxphase;
lfo = (lfo + 1) * 1.; /* Transform from [-1; 1] to [0; 1] */
delay = lfo * core->depth * maxdelay;
delay += VIBRATO_ADD_DELAY;
readindex = core->writeindex - 1 - delay;
while (readindex < 0)
readindex += core->size;
while (readindex >= core->size)
readindex -= core->size;
ipart = (int)readindex; /* Integer part of the delay */
fpart = readindex - ipart; /* fractional part of the delay */
value = hermite_interp(fpart, &(core->buffer[ipart]));
core->buffer[core->writeindex] = in;
if (core->writeindex < VIBRATO_ADD_DELAY)
core->buffer[core->size + core->writeindex] = in;
core->writeindex++;
if (core->writeindex == core->size)
core->writeindex = 0;
return value;
}
static void vibrato_process(void *data,
struct dspfilter_output *output,
const struct dspfilter_input *input)
{
unsigned i;
float *out;
struct vibrato *vib = (struct vibrato*)data;
output->samples = input->samples;
output->frames = input->frames;
out = output->samples;
for (i = 0; i < input->frames; i++, out += 2)
{
float in[2] = { out[0], out[1] };
out[0] = vibratocore_core(&vib->left, in[0]);
out[1] = vibratocore_core(&vib->right, in[1]);
}
}
static void *vibrato_init(const struct dspfilter_info *info,
const struct dspfilter_config *config, void *userdata)
{
float freq, depth;
struct vibrato *vib = (struct vibrato*)calloc(1, sizeof(*vib));
if (!vib)
return NULL;
config->get_float(userdata, "freq", &freq,5.0f);
config->get_float(userdata, "depth", &depth, 0.5f);
vibratocore_init(&vib->left,depth,info->input_rate,freq);
vibratocore_init(&vib->right,depth,info->input_rate,freq);
return vib;
}
static const struct dspfilter_implementation vibrato_plug = {
vibrato_init,
vibrato_process,
vibrato_free,
DSPFILTER_API_VERSION,
"Vibrato",
"vibrato",
};
#ifdef HAVE_FILTERS_BUILTIN
#define dspfilter_get_implementation vibrato_dspfilter_get_implementation
#endif
const struct dspfilter_implementation *dspfilter_get_implementation(dspfilter_simd_mask_t mask)
{
return &vibrato_plug;
}
#undef dspfilter_get_implementation
|
