source: roaraudio/libroardsp/fader.c @ 3626:7fc82747cba3

Last change on this file since 3626:7fc82747cba3 was 3626:7fc82747cba3, checked in by phi, 14 years ago

added functions to request status

File size: 3.5 KB
Line 
1//fader.c:
2
3/*
4 *      Copyright (C) Philipp 'ph3-der-loewe' Schafft - 2009
5 *
6 *  This file is part of libroardsp a part of RoarAudio,
7 *  a cross-platform sound system for both, home and professional use.
8 *  See README for details.
9 *
10 *  This file is free software; you can redistribute it and/or modify
11 *  it under the terms of the GNU General Public License version 3
12 *  as published by the Free Software Foundation.
13 *
14 *  libroardsp is distributed in the hope that it will be useful,
15 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
16 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 *  GNU General Public License for more details.
18 *
19 *  You should have received a copy of the GNU General Public License
20 *  along with this software; see the file COPYING.  If not, write to
21 *  the Free Software Foundation, 51 Franklin Street, Fifth Floor,
22 *  Boston, MA 02110-1301, USA.
23 *
24 */
25
26#include "libroardsp.h"
27
28#define _CHECK_BASIC()   if ( state == NULL ) return -1
29#define _CHECK_CALCPCM() _CHECK_BASIC(); if ( frames == 0 ) return 0; if ( data == NULL ) return -1;
30
31int roar_fader_init         (struct roar_fader_state * state, float * poly, int coeff) {
32 _CHECK_BASIC();
33
34 if ( poly == NULL )
35  return -1;
36
37 if ( coeff < 2 )
38  return -1;
39
40 if ( coeff > ROAR_FADER_MAX_COEFF )
41  return -1;
42
43 memset(state, 0, sizeof(struct roar_fader_state));
44
45 state->rate  = -1;
46 state->coeff = coeff;
47
48 state->start = -1;
49 state->stop  = -1;
50
51 memcpy(state->poly, poly, sizeof(float)*coeff);
52
53 return 0;
54}
55
56int roar_fader_set_rate     (struct roar_fader_state * state, int rate) {
57 _CHECK_BASIC();
58
59 state->rate = rate;
60
61 return 0;
62}
63
64int roar_fader_set_startstop(struct roar_fader_state * state, ssize_t start, ssize_t stop) {
65 _CHECK_BASIC();
66
67 if ( start >= 0 )
68  state->start = start;
69
70 if ( stop  >= 0 )
71  state->stop  = stop;
72
73 return 0;
74}
75
76int roar_fader_has_started  (struct roar_fader_state * state) {
77 if ( state == NULL )
78  return -1;
79
80 if ( state->start == -1 )
81  return 0;
82
83 if ( state->start <= state->pcmoffset )
84  return 1;
85
86 return 0;
87}
88
89int roar_fader_has_ended    (struct roar_fader_state * state) {
90 if ( state == NULL )
91  return -1;
92
93 if ( state->stop == -1 )
94  return 0;
95
96 if ( state->stop > state->pcmoffset )
97  return 1;
98
99 return 0;
100}
101
102int roar_fader_calcpcm_i16n(struct roar_fader_state * state, int16_t * data, size_t frames, int channels) {
103 _CHECK_CALCPCM();
104
105 switch (channels) {
106  case 1: return roar_fader_calcpcm_i161(state, data, frames);
107 }
108
109 return -1;
110}
111
112int roar_fader_calcpcm_i161(struct roar_fader_state * state, int16_t * data, size_t frames) {
113 size_t start, stop, cur;
114 int i, i_s, i_e;
115 float t_cur, t_step;
116 float g_cur;
117
118 _CHECK_BASIC();
119
120 if ( state->start == -1 ) {
121  start = state->pcmoffset;
122 } else {
123  start = state->start;
124 }
125
126 if ( state->stop == -1 ) {
127  stop = state->pcmoffset + frames;
128 } else {
129  stop = state->stop;
130 }
131
132 cur = state->pcmoffset;
133
134 i_s = 0;
135 i_e = frames;
136
137 if ( start > cur )
138  i_s = start - cur;
139
140 if ( stop < (cur + frames) )
141  i_e = stop  - cur;
142
143 t_step = (float)(state->coeff - 1)/(float)(stop - start);
144
145 if ( start < cur ) {
146  t_cur = (cur - start)*t_step;
147 } else {
148  t_cur = 0;
149 }
150
151 ROAR_DBG("roar_fader_calcpcm_i161(*): i_s->i_e: %i->%i", i_s, i_e);
152
153 for (i = i_s; i < i_e; i++, cur++) {
154  t_cur  += t_step;
155  g_cur   = roar_math_cvpoly(state->poly, t_cur, state->coeff);
156//  ROAR_DBG("roar_fader_calcpcm_i161(*): i=%i, g_cur=%f", i, g_cur);
157  data[i] = (float)data[i] * g_cur;
158 }
159
160 state->pcmoffset = cur;
161
162 return -1;
163}
164
165//ll
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