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
|
#include "config.h"
#include <xmms/plugin.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <gtk/gtk.h>
#include "echo.h"
static void init(void);
static void clear_buffer(void);
static void cleanup(void);
static int mod_samples(gpointer * d, gint length, AFormat afmt, gint srate, gint nch);
#define MAX_SRATE 50000
#define MAX_CHANNELS 2
#define BYTES_PS 2
#define BUFFER_SAMPLES (MAX_SRATE * MAX_DELAY / 1000)
#define BUFFER_SHORTS (BUFFER_SAMPLES * MAX_CHANNELS)
#define BUFFER_BYTES (BUFFER_SHORTS * BYTES_PS)
EffectPlugin secho_ep =
{
NULL,
NULL,
"Pro-Logic Surround Echo Plugin " VERSION,
init,
cleanup,
secho_about,
secho_configure,
mod_samples
};
short *buffer;
short *buffer2;
int secho_delay = 500, secho_feedback = 50, secho_volume = 50;
int w_ofs;
int old_srate, old_nch;
EffectPlugin *get_eplugin_info(void)
{
return &secho_ep;
}
static void init(void)
{
buffer = (short *) malloc(BUFFER_BYTES + 1);
buffer2 = (short *) malloc(BUFFER_BYTES + 1);
if (buffer == NULL)
{
perror("Buffer allocation");
gtk_main_quit();
}
if (buffer2 == NULL)
{
perror("Buffer allocation");
gtk_main_quit();
}
clear_buffer();
}
static void clear_buffer(void)
{
bzero(buffer, BUFFER_BYTES);
bzero(buffer2, BUFFER_BYTES);
w_ofs = 0; // short[] index
}
static void cleanup(void)
{
free(buffer);
free(buffer2);
}
static void range(int *v)
{
if (*v < -32768)
*v = -32768;
if (*v > 32767)
*v = 32767;
}
static int mod_samples(gpointer * d, gint length, AFormat afmt, gint srate, gint nch)
{
int x, i, in, out, buf, tmp, r_ofs, left, right;
int inl, inr, outl, outr, bufl, bufr;
gint16 *data = (gint16 *)*d;
if (!(afmt == FMT_S16_NE || (afmt == FMT_S16_LE && G_BYTE_ORDER == G_LITTLE_ENDIAN) || (afmt == FMT_S16_BE && G_BYTE_ORDER == G_BIG_ENDIAN)))
return length;
if (nch != old_nch || srate != old_srate)
{
clear_buffer();
old_nch = nch;
old_srate = srate;
}
r_ofs = w_ofs - (srate * secho_delay / 1000) * nch;
if (r_ofs < 0)
r_ofs += BUFFER_SHORTS;
if (nch == 1)
{
for (i = 0; i < length / BYTES_PS; i++)
{
in = data[i];
buf = buffer[r_ofs];
out = in + buf * secho_volume / 100;
buf = in + buf * secho_feedback / 100;
range(&out);
range(&buf);
buffer[w_ofs] = buf;
data[i] = out;
tmp = data[i];
if (++r_ofs >= BUFFER_SHORTS)
r_ofs -= BUFFER_SHORTS;
if (++w_ofs >= BUFFER_SHORTS)
w_ofs -= BUFFER_SHORTS;
}
}
else
{
short *datas = data;
for (x = 0; x < length / BYTES_PS / 2; x++)
{
bufl = buffer[r_ofs];
bufr = buffer2[r_ofs];
left = bufl - bufr;
right = bufr - bufl;
bufl = left;
bufr = right;
inl = datas[x * 2];
inr = datas[x * 2 + 1];
outl = inl + bufl * secho_volume / 100;
outr = inr + bufr * secho_volume / 100;
bufl = inl + bufl * secho_feedback / 200;
bufr = inr + bufr * secho_feedback / 200;
range(&outl);
range(&outr);
range(&bufl);
range(&bufr);
buffer[w_ofs] = bufl;
buffer2[w_ofs] = bufr;
datas[x * 2] = outl;
datas[x * 2 + 1] = outr;
if (++r_ofs >= BUFFER_SHORTS)
r_ofs -= BUFFER_SHORTS;
if (++w_ofs >= BUFFER_SHORTS)
w_ofs -= BUFFER_SHORTS;
}
}
return length;
}
|
