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199
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1 /*
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2
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3 TiMidity -- Experimental MIDI to WAVE converter
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4 Copyright (C) 1995 Tuukka Toivonen <toivonen@clinet.fi>
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5
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6 This program is free software; you can redistribute it and/or modify
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7 it under the terms of the GNU General Public License as published by
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8 the Free Software Foundation; either version 2 of the License, or
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9 (at your option) any later version.
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10
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11 This program is distributed in the hope that it will be useful,
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12 but WITHOUT ANY WARRANTY; without even the implied warranty of
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13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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14 GNU General Public License for more details.
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15
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16 You should have received a copy of the GNU General Public License
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17 along with this program; if not, write to the Free Software
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18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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19
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20 resample.c
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21 */
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22
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23 #if HAVE_CONFIG_H
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24 # include <config.h>
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25 #endif
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26
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27 #include <math.h>
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28 #include <stdio.h>
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29 #include <stdlib.h>
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30
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31 #include "SDL_sound.h"
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32
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33 #define __SDL_SOUND_INTERNAL__
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34 #include "SDL_sound_internal.h"
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35
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36 #include "timidity.h"
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37 #include "options.h"
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38 #include "common.h"
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39 #include "instrum.h"
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40 #include "playmidi.h"
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41 #include "tables.h"
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42 #include "resample.h"
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43
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44 /*************** resampling with fixed increment *****************/
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45
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46 static sample_t *rs_plain(MidiSong *song, int v, Sint32 *countptr)
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47 {
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48
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49 /* Play sample until end, then free the voice. */
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50
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51 sample_t v1, v2;
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52 Voice
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53 *vp=&(song->voice[v]);
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54 sample_t
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55 *dest=song->resample_buffer,
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56 *src=vp->sample->data;
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57 Sint32
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58 ofs=vp->sample_offset,
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59 incr=vp->sample_increment,
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60 le=vp->sample->data_length,
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61 count=*countptr;
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62 Sint32 i;
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63
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64 if (incr<0) incr = -incr; /* In case we're coming out of a bidir loop */
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65
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66 /* Precalc how many times we should go through the loop.
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67 NOTE: Assumes that incr > 0 and that ofs <= le */
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68 i = (le - ofs) / incr + 1;
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69
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70 if (i > count)
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71 {
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72 i = count;
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73 count = 0;
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74 }
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75 else count -= i;
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76
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77 while (i--)
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78 {
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79 v1 = src[ofs >> FRACTION_BITS];
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80 v2 = src[(ofs >> FRACTION_BITS)+1];
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81 *dest++ = v1 + (((v2 - v1) * (ofs & FRACTION_MASK)) >> FRACTION_BITS);
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82 ofs += incr;
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83 }
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84
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85 if (ofs >= le)
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86 {
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87 if (ofs == le)
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88 *dest++ = src[ofs >> FRACTION_BITS];
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89 vp->status=VOICE_FREE;
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90 *countptr-=count+1;
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91 }
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92
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93 vp->sample_offset=ofs; /* Update offset */
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94 return song->resample_buffer;
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95 }
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96
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97 static sample_t *rs_loop(MidiSong *song, Voice *vp, Sint32 count)
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98 {
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99
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100 /* Play sample until end-of-loop, skip back and continue. */
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101
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102 sample_t v1, v2;
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103 Sint32
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104 ofs=vp->sample_offset,
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105 incr=vp->sample_increment,
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106 le=vp->sample->loop_end,
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107 ll=le - vp->sample->loop_start;
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108 sample_t
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109 *dest=song->resample_buffer,
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110 *src=vp->sample->data;
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111 Sint32 i;
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112
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113 while (count)
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114 {
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115 if (ofs >= le)
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116 /* NOTE: Assumes that ll > incr and that incr > 0. */
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117 ofs -= ll;
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118 /* Precalc how many times we should go through the loop */
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119 i = (le - ofs) / incr + 1;
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120 if (i > count)
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121 {
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122 i = count;
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123 count = 0;
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124 }
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125 else count -= i;
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126 while (i--)
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127 {
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128 v1 = src[ofs >> FRACTION_BITS];
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129 v2 = src[(ofs >> FRACTION_BITS)+1];
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130 *dest++ = v1 + (((v2 - v1) * (ofs & FRACTION_MASK)) >> FRACTION_BITS);
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131 ofs += incr;
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132 }
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133 }
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134
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135 vp->sample_offset=ofs; /* Update offset */
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136 return song->resample_buffer;
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137 }
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138
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139 static sample_t *rs_bidir(MidiSong *song, Voice *vp, Sint32 count)
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140 {
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141 sample_t v1, v2;
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142 Sint32
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143 ofs=vp->sample_offset,
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144 incr=vp->sample_increment,
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145 le=vp->sample->loop_end,
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146 ls=vp->sample->loop_start;
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147 sample_t
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148 *dest=song->resample_buffer,
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149 *src=vp->sample->data;
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150 Sint32
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151 le2 = le<<1,
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152 ls2 = ls<<1,
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153 i;
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154 /* Play normally until inside the loop region */
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155
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156 if (ofs <= ls)
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157 {
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158 /* NOTE: Assumes that incr > 0, which is NOT always the case
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159 when doing bidirectional looping. I have yet to see a case
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160 where both ofs <= ls AND incr < 0, however. */
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161 i = (ls - ofs) / incr + 1;
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162 if (i > count)
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163 {
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164 i = count;
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165 count = 0;
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166 }
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167 else count -= i;
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168 while (i--)
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169 {
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170 v1 = src[ofs >> FRACTION_BITS];
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171 v2 = src[(ofs >> FRACTION_BITS)+1];
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172 *dest++ = v1 + (((v2 - v1) * (ofs & FRACTION_MASK)) >> FRACTION_BITS);
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173 ofs += incr;
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174 }
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175 }
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176
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177 /* Then do the bidirectional looping */
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178
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179 while(count)
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180 {
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181 /* Precalc how many times we should go through the loop */
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182 i = ((incr > 0 ? le : ls) - ofs) / incr + 1;
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183 if (i > count)
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184 {
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185 i = count;
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186 count = 0;
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187 }
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188 else count -= i;
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189 while (i--)
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190 {
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191 v1 = src[ofs >> FRACTION_BITS];
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192 v2 = src[(ofs >> FRACTION_BITS)+1];
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193 *dest++ = v1 + (((v2 - v1) * (ofs & FRACTION_MASK)) >> FRACTION_BITS);
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194 ofs += incr;
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195 }
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196 if (ofs>=le)
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197 {
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198 /* fold the overshoot back in */
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199 ofs = le2 - ofs;
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200 incr *= -1;
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201 }
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202 else if (ofs <= ls)
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203 {
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204 ofs = ls2 - ofs;
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205 incr *= -1;
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206 }
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207 }
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208
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209 vp->sample_increment=incr;
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210 vp->sample_offset=ofs; /* Update offset */
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211 return song->resample_buffer;
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212 }
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213
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214 /*********************** vibrato versions ***************************/
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215
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216 /* We only need to compute one half of the vibrato sine cycle */
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217 static int vib_phase_to_inc_ptr(int phase)
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218 {
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219 if (phase < VIBRATO_SAMPLE_INCREMENTS/2)
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220 return VIBRATO_SAMPLE_INCREMENTS/2-1-phase;
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221 else if (phase >= 3*VIBRATO_SAMPLE_INCREMENTS/2)
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222 return 5*VIBRATO_SAMPLE_INCREMENTS/2-1-phase;
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223 else
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224 return phase-VIBRATO_SAMPLE_INCREMENTS/2;
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225 }
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226
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227 static Sint32 update_vibrato(MidiSong *song, Voice *vp, int sign)
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228 {
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229 Sint32 depth;
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230 int phase, pb;
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231 double a;
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232
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233 if (vp->vibrato_phase++ >= 2*VIBRATO_SAMPLE_INCREMENTS-1)
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234 vp->vibrato_phase=0;
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235 phase=vib_phase_to_inc_ptr(vp->vibrato_phase);
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236
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237 if (vp->vibrato_sample_increment[phase])
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238 {
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239 if (sign)
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240 return -vp->vibrato_sample_increment[phase];
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241 else
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242 return vp->vibrato_sample_increment[phase];
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243 }
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244
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245 /* Need to compute this sample increment. */
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246
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247 depth=vp->sample->vibrato_depth<<7;
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248
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249 if (vp->vibrato_sweep)
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250 {
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251 /* Need to update sweep */
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252 vp->vibrato_sweep_position += vp->vibrato_sweep;
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253 if (vp->vibrato_sweep_position >= (1<<SWEEP_SHIFT))
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254 vp->vibrato_sweep=0;
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255 else
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256 {
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257 /* Adjust depth */
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258 depth *= vp->vibrato_sweep_position;
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259 depth >>= SWEEP_SHIFT;
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260 }
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261 }
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262
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263 a = FSCALE(((double)(vp->sample->sample_rate) *
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264 (double)(vp->frequency)) /
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265 ((double)(vp->sample->root_freq) *
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266 (double)(song->rate)),
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267 FRACTION_BITS);
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268
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269 pb=(int)((sine(vp->vibrato_phase *
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270 (SINE_CYCLE_LENGTH/(2*VIBRATO_SAMPLE_INCREMENTS)))
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271 * (double)(depth) * VIBRATO_AMPLITUDE_TUNING));
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272
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273 if (pb<0)
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274 {
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275 pb=-pb;
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276 a /= bend_fine[(pb>>5) & 0xFF] * bend_coarse[pb>>13];
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277 }
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278 else
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279 a *= bend_fine[(pb>>5) & 0xFF] * bend_coarse[pb>>13];
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280
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281 /* If the sweep's over, we can store the newly computed sample_increment */
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282 if (!vp->vibrato_sweep)
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283 vp->vibrato_sample_increment[phase]=(Sint32) a;
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284
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285 if (sign)
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286 a = -a; /* need to preserve the loop direction */
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287
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288 return (Sint32) a;
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289 }
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290
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291 static sample_t *rs_vib_plain(MidiSong *song, int v, Sint32 *countptr)
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292 {
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293
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294 /* Play sample until end, then free the voice. */
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295
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296 sample_t v1, v2;
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297 Voice *vp=&(song->voice[v]);
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298 sample_t
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299 *dest=song->resample_buffer,
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300 *src=vp->sample->data;
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301 Sint32
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302 le=vp->sample->data_length,
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303 ofs=vp->sample_offset,
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304 incr=vp->sample_increment,
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305 count=*countptr;
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306 int
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307 cc=vp->vibrato_control_counter;
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308
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309 /* This has never been tested */
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310
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311 if (incr<0) incr = -incr; /* In case we're coming out of a bidir loop */
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312
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313 while (count--)
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314 {
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315 if (!cc--)
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316 {
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317 cc=vp->vibrato_control_ratio;
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318 incr=update_vibrato(song, vp, 0);
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319 }
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320 v1 = src[ofs >> FRACTION_BITS];
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321 v2 = src[(ofs >> FRACTION_BITS)+1];
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322 *dest++ = v1 + (((v2 - v1) * (ofs & FRACTION_MASK)) >> FRACTION_BITS);
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323 ofs += incr;
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324 if (ofs >= le)
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325 {
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326 if (ofs == le)
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327 *dest++ = src[ofs >> FRACTION_BITS];
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328 vp->status=VOICE_FREE;
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329 *countptr-=count+1;
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330 break;
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331 }
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332 }
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333
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334 vp->vibrato_control_counter=cc;
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335 vp->sample_increment=incr;
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336 vp->sample_offset=ofs; /* Update offset */
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337 return song->resample_buffer;
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338 }
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339
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340 static sample_t *rs_vib_loop(MidiSong *song, Voice *vp, Sint32 count)
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341 {
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342
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343 /* Play sample until end-of-loop, skip back and continue. */
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344
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345 sample_t v1, v2;
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346 Sint32
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347 ofs=vp->sample_offset,
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348 incr=vp->sample_increment,
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349 le=vp->sample->loop_end,
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350 ll=le - vp->sample->loop_start;
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351 sample_t
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352 *dest=song->resample_buffer,
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353 *src=vp->sample->data;
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354 int
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355 cc=vp->vibrato_control_counter;
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356 Sint32 i;
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357 int
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358 vibflag=0;
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359
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360 while (count)
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361 {
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362 /* Hopefully the loop is longer than an increment */
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363 if(ofs >= le)
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364 ofs -= ll;
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365 /* Precalc how many times to go through the loop, taking
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366 the vibrato control ratio into account this time. */
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367 i = (le - ofs) / incr + 1;
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368 if(i > count) i = count;
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369 if(i > cc)
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370 {
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371 i = cc;
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372 vibflag = 1;
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373 }
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374 else cc -= i;
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375 count -= i;
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376 while(i--)
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377 {
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378 v1 = src[ofs >> FRACTION_BITS];
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379 v2 = src[(ofs >> FRACTION_BITS)+1];
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380 *dest++ = v1 + (((v2 - v1) * (ofs & FRACTION_MASK)) >> FRACTION_BITS);
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381 ofs += incr;
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382 }
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383 if(vibflag)
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384 {
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385 cc = vp->vibrato_control_ratio;
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386 incr = update_vibrato(song, vp, 0);
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387 vibflag = 0;
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388 }
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389 }
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390
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391 vp->vibrato_control_counter=cc;
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392 vp->sample_increment=incr;
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393 vp->sample_offset=ofs; /* Update offset */
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394 return song->resample_buffer;
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395 }
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396
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397 static sample_t *rs_vib_bidir(MidiSong *song, Voice *vp, Sint32 count)
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398 {
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399 sample_t v1, v2;
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400 Sint32
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401 ofs=vp->sample_offset,
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402 incr=vp->sample_increment,
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403 le=vp->sample->loop_end,
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404 ls=vp->sample->loop_start;
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405 sample_t
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406 *dest=song->resample_buffer,
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407 *src=vp->sample->data;
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408 int
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409 cc=vp->vibrato_control_counter;
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410 Sint32
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411 le2=le<<1,
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412 ls2=ls<<1,
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413 i;
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414 int
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415 vibflag = 0;
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416
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417 /* Play normally until inside the loop region */
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418 while (count && (ofs <= ls))
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419 {
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420 i = (ls - ofs) / incr + 1;
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421 if (i > count) i = count;
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422 if (i > cc)
|
|
|
423 {
|
|
|
424 i = cc;
|
|
|
425 vibflag = 1;
|
|
|
426 }
|
|
|
427 else cc -= i;
|
|
|
428 count -= i;
|
|
|
429 while (i--)
|
|
|
430 {
|
|
|
431 v1 = src[ofs >> FRACTION_BITS];
|
|
|
432 v2 = src[(ofs >> FRACTION_BITS)+1];
|
|
|
433 *dest++ = v1 + (((v2 - v1) * (ofs & FRACTION_MASK)) >> FRACTION_BITS);
|
|
|
434 ofs += incr;
|
|
|
435 }
|
|
|
436 if (vibflag)
|
|
|
437 {
|
|
|
438 cc = vp->vibrato_control_ratio;
|
|
|
439 incr = update_vibrato(song, vp, 0);
|
|
|
440 vibflag = 0;
|
|
|
441 }
|
|
|
442 }
|
|
|
443
|
|
|
444 /* Then do the bidirectional looping */
|
|
|
445
|
|
|
446 while (count)
|
|
|
447 {
|
|
|
448 /* Precalc how many times we should go through the loop */
|
|
|
449 i = ((incr > 0 ? le : ls) - ofs) / incr + 1;
|
|
|
450 if(i > count) i = count;
|
|
|
451 if(i > cc)
|
|
|
452 {
|
|
|
453 i = cc;
|
|
|
454 vibflag = 1;
|
|
|
455 }
|
|
|
456 else cc -= i;
|
|
|
457 count -= i;
|
|
|
458 while (i--)
|
|
|
459 {
|
|
|
460 v1 = src[ofs >> FRACTION_BITS];
|
|
|
461 v2 = src[(ofs >> FRACTION_BITS)+1];
|
|
|
462 *dest++ = v1 + (((v2 - v1) * (ofs & FRACTION_MASK)) >> FRACTION_BITS);
|
|
|
463 ofs += incr;
|
|
|
464 }
|
|
|
465 if (vibflag)
|
|
|
466 {
|
|
|
467 cc = vp->vibrato_control_ratio;
|
|
|
468 incr = update_vibrato(song, vp, (incr < 0));
|
|
|
469 vibflag = 0;
|
|
|
470 }
|
|
|
471 if (ofs >= le)
|
|
|
472 {
|
|
|
473 /* fold the overshoot back in */
|
|
|
474 ofs = le2 - ofs;
|
|
|
475 incr *= -1;
|
|
|
476 }
|
|
|
477 else if (ofs <= ls)
|
|
|
478 {
|
|
|
479 ofs = ls2 - ofs;
|
|
|
480 incr *= -1;
|
|
|
481 }
|
|
|
482 }
|
|
|
483
|
|
|
484 vp->vibrato_control_counter=cc;
|
|
|
485 vp->sample_increment=incr;
|
|
|
486 vp->sample_offset=ofs; /* Update offset */
|
|
|
487 return song->resample_buffer;
|
|
|
488 }
|
|
|
489
|
|
|
490 sample_t *resample_voice(MidiSong *song, int v, Sint32 *countptr)
|
|
|
491 {
|
|
|
492 Sint32 ofs;
|
|
|
493 Uint8 modes;
|
|
|
494 Voice *vp=&(song->voice[v]);
|
|
|
495
|
|
|
496 if (!(vp->sample->sample_rate))
|
|
|
497 {
|
|
|
498 /* Pre-resampled data -- just update the offset and check if
|
|
|
499 we're out of data. */
|
|
|
500 ofs=vp->sample_offset >> FRACTION_BITS; /* Kind of silly to use
|
|
|
501 FRACTION_BITS here... */
|
|
|
502 if (*countptr >= (vp->sample->data_length>>FRACTION_BITS) - ofs)
|
|
|
503 {
|
|
|
504 /* Note finished. Free the voice. */
|
|
|
505 vp->status = VOICE_FREE;
|
|
|
506
|
|
|
507 /* Let the caller know how much data we had left */
|
|
|
508 *countptr = (vp->sample->data_length>>FRACTION_BITS) - ofs;
|
|
|
509 }
|
|
|
510 else
|
|
|
511 vp->sample_offset += *countptr << FRACTION_BITS;
|
|
|
512
|
|
|
513 return vp->sample->data+ofs;
|
|
|
514 }
|
|
|
515
|
|
|
516 /* Need to resample. Use the proper function. */
|
|
|
517 modes=vp->sample->modes;
|
|
|
518
|
|
|
519 if (vp->vibrato_control_ratio)
|
|
|
520 {
|
|
|
521 if ((modes & MODES_LOOPING) &&
|
|
|
522 ((modes & MODES_ENVELOPE) ||
|
|
|
523 (vp->status==VOICE_ON || vp->status==VOICE_SUSTAINED)))
|
|
|
524 {
|
|
|
525 if (modes & MODES_PINGPONG)
|
|
|
526 return rs_vib_bidir(song, vp, *countptr);
|
|
|
527 else
|
|
|
528 return rs_vib_loop(song, vp, *countptr);
|
|
|
529 }
|
|
|
530 else
|
|
|
531 return rs_vib_plain(song, v, countptr);
|
|
|
532 }
|
|
|
533 else
|
|
|
534 {
|
|
|
535 if ((modes & MODES_LOOPING) &&
|
|
|
536 ((modes & MODES_ENVELOPE) ||
|
|
|
537 (vp->status==VOICE_ON || vp->status==VOICE_SUSTAINED)))
|
|
|
538 {
|
|
|
539 if (modes & MODES_PINGPONG)
|
|
|
540 return rs_bidir(song, vp, *countptr);
|
|
|
541 else
|
|
|
542 return rs_loop(song, vp, *countptr);
|
|
|
543 }
|
|
|
544 else
|
|
|
545 return rs_plain(song, v, countptr);
|
|
|
546 }
|
|
|
547 }
|
|
|
548
|
|
|
549 void pre_resample(MidiSong *song, Sample *sp)
|
|
|
550 {
|
|
|
551 double a, xdiff;
|
|
|
552 Sint32 incr, ofs, newlen, count;
|
|
|
553 Sint16 *newdata, *dest, *src = (Sint16 *) sp->data;
|
|
|
554 Sint16 v1, v2, v3, v4, *vptr;
|
|
|
555 #ifdef DEBUG_CHATTER
|
|
|
556 static const char note_name[12][3] =
|
|
|
557 {
|
|
|
558 "C", "C#", "D", "D#", "E", "F", "F#", "G", "G#", "A", "A#", "B"
|
|
|
559 };
|
|
|
560 #endif
|
|
|
561
|
|
|
562 SNDDBG((" * pre-resampling for note %d (%s%d)\n",
|
|
|
563 sp->note_to_use,
|
|
|
564 note_name[sp->note_to_use % 12], (sp->note_to_use & 0x7F) / 12));
|
|
|
565
|
|
|
566 a = ((double) (sp->sample_rate) * freq_table[(int) (sp->note_to_use)]) /
|
|
|
567 ((double) (sp->root_freq) * song->rate);
|
|
|
568 newlen = (Sint32)(sp->data_length / a);
|
|
|
569 dest = newdata = safe_malloc(newlen >> (FRACTION_BITS - 1));
|
|
|
570
|
|
|
571 count = (newlen >> FRACTION_BITS) - 1;
|
|
|
572 ofs = incr = (sp->data_length - (1 << FRACTION_BITS)) / count;
|
|
|
573
|
|
|
574 if (--count)
|
|
|
575 *dest++ = src[0];
|
|
|
576
|
|
|
577 /* Since we're pre-processing and this doesn't have to be done in
|
|
|
578 real-time, we go ahead and do the full sliding cubic interpolation. */
|
|
|
579 while (--count)
|
|
|
580 {
|
|
|
581 vptr = src + (ofs >> FRACTION_BITS);
|
|
254
|
582 /*
|
|
|
583 * Electric Fence to the rescue: Accessing *(vptr - 1) is not a
|
|
|
584 * good thing to do when vptr <= src. (TiMidity++ has a similar
|
|
|
585 * safe-guard here.)
|
|
|
586 */
|
|
|
587 v1 = (vptr > src) ? *(vptr - 1) : 0;
|
|
199
|
588 v2 = *vptr;
|
|
|
589 v3 = *(vptr + 1);
|
|
|
590 v4 = *(vptr + 2);
|
|
|
591 xdiff = FSCALENEG(ofs & FRACTION_MASK, FRACTION_BITS);
|
|
|
592 *dest++ = (Sint16)(v2 + (xdiff / 6.0) * (-2 * v1 - 3 * v2 + 6 * v3 - v4 +
|
|
|
593 xdiff * (3 * (v1 - 2 * v2 + v3) + xdiff * (-v1 + 3 * (v2 - v3) + v4))));
|
|
|
594 ofs += incr;
|
|
|
595 }
|
|
|
596
|
|
|
597 if (ofs & FRACTION_MASK)
|
|
|
598 {
|
|
|
599 v1 = src[ofs >> FRACTION_BITS];
|
|
|
600 v2 = src[(ofs >> FRACTION_BITS) + 1];
|
|
|
601 *dest++ = v1 + (((v2 - v1) * (ofs & FRACTION_MASK)) >> FRACTION_BITS);
|
|
|
602 }
|
|
|
603 else
|
|
|
604 *dest++ = src[ofs >> FRACTION_BITS];
|
|
|
605
|
|
|
606 sp->data_length = newlen;
|
|
|
607 sp->loop_start = (Sint32)(sp->loop_start / a);
|
|
|
608 sp->loop_end = (Sint32)(sp->loop_end / a);
|
|
|
609 free(sp->data);
|
|
|
610 sp->data = (sample_t *) newdata;
|
|
|
611 sp->sample_rate = 0;
|
|
|
612 }
|
