annotate src/audio/SDL_wave.c @ 1228:f4a3a4129d04

From Mike Frysinger and/or Gentoo: - libsdl-SDL_stretch-PIC.patch ignoring the general fact of how SDL_stretch relies on executing dynamic code, the inline asm should let gcc handle the a details for getting the actual address for _copy_row as it will do the right thing test case: http://dev.gentoo.org/~vapier/libsdl/sdl-stretch.tar.bz2
author Ryan C. Gordon <icculus@icculus.org>
date Thu, 05 Jan 2006 07:20:12 +0000
parents b8d311d90021
children 80f8c94b5199
rev   line source
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1 /*
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2 SDL - Simple DirectMedia Layer
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b8d311d90021 Updated copyright information for 2004 (Happy New Year!)
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3 Copyright (C) 1997-2004 Sam Lantinga
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4
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5 This library is free software; you can redistribute it and/or
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6 modify it under the terms of the GNU Library General Public
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7 License as published by the Free Software Foundation; either
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8 version 2 of the License, or (at your option) any later version.
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9
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10 This library is distributed in the hope that it will be useful,
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11 but WITHOUT ANY WARRANTY; without even the implied warranty of
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12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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13 Library General Public License for more details.
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14
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15 You should have received a copy of the GNU Library General Public
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16 License along with this library; if not, write to the Free
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17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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18
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19 Sam Lantinga
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20 slouken@libsdl.org
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21 */
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22
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23 #ifdef SAVE_RCSID
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24 static char rcsid =
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25 "@(#) $Id$";
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26 #endif
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27
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28 #ifndef DISABLE_FILE
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29
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30 /* Microsoft WAVE file loading routines */
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31
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32 #include <stdlib.h>
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33 #include <string.h>
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34
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35 #include "SDL_error.h"
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36 #include "SDL_audio.h"
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37 #include "SDL_wave.h"
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38 #include "SDL_endian.h"
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39
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40 #ifndef NELEMS
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41 #define NELEMS(array) ((sizeof array)/(sizeof array[0]))
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42 #endif
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43
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44 static int ReadChunk(SDL_RWops *src, Chunk *chunk);
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45
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46 struct MS_ADPCM_decodestate {
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47 Uint8 hPredictor;
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48 Uint16 iDelta;
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49 Sint16 iSamp1;
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50 Sint16 iSamp2;
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51 };
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52 static struct MS_ADPCM_decoder {
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53 WaveFMT wavefmt;
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54 Uint16 wSamplesPerBlock;
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55 Uint16 wNumCoef;
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56 Sint16 aCoeff[7][2];
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57 /* * * */
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58 struct MS_ADPCM_decodestate state[2];
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59 } MS_ADPCM_state;
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60
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61 static int InitMS_ADPCM(WaveFMT *format)
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62 {
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63 Uint8 *rogue_feel;
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64 Uint16 extra_info;
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65 int i;
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66
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67 /* Set the rogue pointer to the MS_ADPCM specific data */
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68 MS_ADPCM_state.wavefmt.encoding = SDL_SwapLE16(format->encoding);
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69 MS_ADPCM_state.wavefmt.channels = SDL_SwapLE16(format->channels);
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70 MS_ADPCM_state.wavefmt.frequency = SDL_SwapLE32(format->frequency);
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71 MS_ADPCM_state.wavefmt.byterate = SDL_SwapLE32(format->byterate);
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72 MS_ADPCM_state.wavefmt.blockalign = SDL_SwapLE16(format->blockalign);
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73 MS_ADPCM_state.wavefmt.bitspersample =
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74 SDL_SwapLE16(format->bitspersample);
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75 rogue_feel = (Uint8 *)format+sizeof(*format);
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76 if ( sizeof(*format) == 16 ) {
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77 extra_info = ((rogue_feel[1]<<8)|rogue_feel[0]);
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78 rogue_feel += sizeof(Uint16);
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79 }
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80 MS_ADPCM_state.wSamplesPerBlock = ((rogue_feel[1]<<8)|rogue_feel[0]);
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81 rogue_feel += sizeof(Uint16);
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82 MS_ADPCM_state.wNumCoef = ((rogue_feel[1]<<8)|rogue_feel[0]);
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83 rogue_feel += sizeof(Uint16);
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84 if ( MS_ADPCM_state.wNumCoef != 7 ) {
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85 SDL_SetError("Unknown set of MS_ADPCM coefficients");
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86 return(-1);
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87 }
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88 for ( i=0; i<MS_ADPCM_state.wNumCoef; ++i ) {
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89 MS_ADPCM_state.aCoeff[i][0] = ((rogue_feel[1]<<8)|rogue_feel[0]);
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90 rogue_feel += sizeof(Uint16);
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91 MS_ADPCM_state.aCoeff[i][1] = ((rogue_feel[1]<<8)|rogue_feel[0]);
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92 rogue_feel += sizeof(Uint16);
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93 }
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94 return(0);
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95 }
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96
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97 static Sint32 MS_ADPCM_nibble(struct MS_ADPCM_decodestate *state,
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98 Uint8 nybble, Sint16 *coeff)
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99 {
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100 const Sint32 max_audioval = ((1<<(16-1))-1);
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101 const Sint32 min_audioval = -(1<<(16-1));
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102 const Sint32 adaptive[] = {
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103 230, 230, 230, 230, 307, 409, 512, 614,
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104 768, 614, 512, 409, 307, 230, 230, 230
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105 };
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106 Sint32 new_sample, delta;
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107
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108 new_sample = ((state->iSamp1 * coeff[0]) +
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109 (state->iSamp2 * coeff[1]))/256;
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110 if ( nybble & 0x08 ) {
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111 new_sample += state->iDelta * (nybble-0x10);
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112 } else {
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113 new_sample += state->iDelta * nybble;
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114 }
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115 if ( new_sample < min_audioval ) {
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116 new_sample = min_audioval;
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117 } else
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118 if ( new_sample > max_audioval ) {
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119 new_sample = max_audioval;
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120 }
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121 delta = ((Sint32)state->iDelta * adaptive[nybble])/256;
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122 if ( delta < 16 ) {
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123 delta = 16;
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124 }
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125 state->iDelta = delta;
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126 state->iSamp2 = state->iSamp1;
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127 state->iSamp1 = new_sample;
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128 return(new_sample);
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129 }
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130
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131 static int MS_ADPCM_decode(Uint8 **audio_buf, Uint32 *audio_len)
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132 {
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133 struct MS_ADPCM_decodestate *state[2];
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134 Uint8 *freeable, *encoded, *decoded;
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135 Sint32 encoded_len, samplesleft;
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136 Sint8 nybble, stereo;
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137 Sint16 *coeff[2];
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138 Sint32 new_sample;
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139
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140 /* Allocate the proper sized output buffer */
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141 encoded_len = *audio_len;
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142 encoded = *audio_buf;
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143 freeable = *audio_buf;
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144 *audio_len = (encoded_len/MS_ADPCM_state.wavefmt.blockalign) *
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145 MS_ADPCM_state.wSamplesPerBlock*
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146 MS_ADPCM_state.wavefmt.channels*sizeof(Sint16);
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147 *audio_buf = (Uint8 *)malloc(*audio_len);
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148 if ( *audio_buf == NULL ) {
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149 SDL_Error(SDL_ENOMEM);
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150 return(-1);
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151 }
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152 decoded = *audio_buf;
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153
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154 /* Get ready... Go! */
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155 stereo = (MS_ADPCM_state.wavefmt.channels == 2);
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156 state[0] = &MS_ADPCM_state.state[0];
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157 state[1] = &MS_ADPCM_state.state[stereo];
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158 while ( encoded_len >= MS_ADPCM_state.wavefmt.blockalign ) {
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159 /* Grab the initial information for this block */
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160 state[0]->hPredictor = *encoded++;
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161 if ( stereo ) {
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
162 state[1]->hPredictor = *encoded++;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
163 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
164 state[0]->iDelta = ((encoded[1]<<8)|encoded[0]);
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
165 encoded += sizeof(Sint16);
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
166 if ( stereo ) {
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
167 state[1]->iDelta = ((encoded[1]<<8)|encoded[0]);
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
168 encoded += sizeof(Sint16);
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
169 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
170 state[0]->iSamp1 = ((encoded[1]<<8)|encoded[0]);
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
171 encoded += sizeof(Sint16);
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
172 if ( stereo ) {
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
173 state[1]->iSamp1 = ((encoded[1]<<8)|encoded[0]);
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
174 encoded += sizeof(Sint16);
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
175 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
176 state[0]->iSamp2 = ((encoded[1]<<8)|encoded[0]);
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
177 encoded += sizeof(Sint16);
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
178 if ( stereo ) {
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
179 state[1]->iSamp2 = ((encoded[1]<<8)|encoded[0]);
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
180 encoded += sizeof(Sint16);
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
181 }
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
182 coeff[0] = MS_ADPCM_state.aCoeff[state[0]->hPredictor];
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
183 coeff[1] = MS_ADPCM_state.aCoeff[state[1]->hPredictor];
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
184
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
185 /* Store the two initial samples we start with */
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
186 decoded[0] = state[0]->iSamp2&0xFF;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
187 decoded[1] = state[0]->iSamp2>>8;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
188 decoded += 2;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
189 if ( stereo ) {
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
190 decoded[0] = state[1]->iSamp2&0xFF;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
191 decoded[1] = state[1]->iSamp2>>8;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
192 decoded += 2;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
193 }
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
194 decoded[0] = state[0]->iSamp1&0xFF;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
195 decoded[1] = state[0]->iSamp1>>8;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
196 decoded += 2;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
197 if ( stereo ) {
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
198 decoded[0] = state[1]->iSamp1&0xFF;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
199 decoded[1] = state[1]->iSamp1>>8;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
200 decoded += 2;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
201 }
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
202
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
203 /* Decode and store the other samples in this block */
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
204 samplesleft = (MS_ADPCM_state.wSamplesPerBlock-2)*
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
205 MS_ADPCM_state.wavefmt.channels;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
206 while ( samplesleft > 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
207 nybble = (*encoded)>>4;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
208 new_sample = MS_ADPCM_nibble(state[0],nybble,coeff[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
209 decoded[0] = new_sample&0xFF;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
210 new_sample >>= 8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
211 decoded[1] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
212 decoded += 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
213
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
214 nybble = (*encoded)&0x0F;
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
215 new_sample = MS_ADPCM_nibble(state[1],nybble,coeff[1]);
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Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
216 decoded[0] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
217 new_sample >>= 8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
218 decoded[1] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
219 decoded += 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
220
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
221 ++encoded;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
222 samplesleft -= 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
223 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
224 encoded_len -= MS_ADPCM_state.wavefmt.blockalign;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
225 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
226 free(freeable);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
227 return(0);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
228 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
229
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
230 struct IMA_ADPCM_decodestate {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
231 Sint32 sample;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
232 Sint8 index;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
233 };
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
234 static struct IMA_ADPCM_decoder {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
235 WaveFMT wavefmt;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
236 Uint16 wSamplesPerBlock;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
237 /* * * */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
238 struct IMA_ADPCM_decodestate state[2];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
239 } IMA_ADPCM_state;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
240
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
241 static int InitIMA_ADPCM(WaveFMT *format)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
242 {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
243 Uint8 *rogue_feel;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
244 Uint16 extra_info;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
245
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
246 /* Set the rogue pointer to the IMA_ADPCM specific data */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
247 IMA_ADPCM_state.wavefmt.encoding = SDL_SwapLE16(format->encoding);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
248 IMA_ADPCM_state.wavefmt.channels = SDL_SwapLE16(format->channels);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
249 IMA_ADPCM_state.wavefmt.frequency = SDL_SwapLE32(format->frequency);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
250 IMA_ADPCM_state.wavefmt.byterate = SDL_SwapLE32(format->byterate);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
251 IMA_ADPCM_state.wavefmt.blockalign = SDL_SwapLE16(format->blockalign);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
252 IMA_ADPCM_state.wavefmt.bitspersample =
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
253 SDL_SwapLE16(format->bitspersample);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
254 rogue_feel = (Uint8 *)format+sizeof(*format);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
255 if ( sizeof(*format) == 16 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
256 extra_info = ((rogue_feel[1]<<8)|rogue_feel[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
257 rogue_feel += sizeof(Uint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
258 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
259 IMA_ADPCM_state.wSamplesPerBlock = ((rogue_feel[1]<<8)|rogue_feel[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
260 return(0);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
261 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
262
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
263 static Sint32 IMA_ADPCM_nibble(struct IMA_ADPCM_decodestate *state,Uint8 nybble)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
264 {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
265 const Sint32 max_audioval = ((1<<(16-1))-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
266 const Sint32 min_audioval = -(1<<(16-1));
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
267 const int index_table[16] = {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
268 -1, -1, -1, -1,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
269 2, 4, 6, 8,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
270 -1, -1, -1, -1,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
271 2, 4, 6, 8
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
272 };
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
273 const Sint32 step_table[89] = {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
274 7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 19, 21, 23, 25, 28, 31,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
275 34, 37, 41, 45, 50, 55, 60, 66, 73, 80, 88, 97, 107, 118, 130,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
276 143, 157, 173, 190, 209, 230, 253, 279, 307, 337, 371, 408,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
277 449, 494, 544, 598, 658, 724, 796, 876, 963, 1060, 1166, 1282,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
278 1411, 1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024, 3327,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
279 3660, 4026, 4428, 4871, 5358, 5894, 6484, 7132, 7845, 8630,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
280 9493, 10442, 11487, 12635, 13899, 15289, 16818, 18500, 20350,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
281 22385, 24623, 27086, 29794, 32767
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
282 };
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
283 Sint32 delta, step;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
284
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
285 /* Compute difference and new sample value */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
286 step = step_table[state->index];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
287 delta = step >> 3;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
288 if ( nybble & 0x04 ) delta += step;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
289 if ( nybble & 0x02 ) delta += (step >> 1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
290 if ( nybble & 0x01 ) delta += (step >> 2);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
291 if ( nybble & 0x08 ) delta = -delta;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
292 state->sample += delta;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
293
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
294 /* Update index value */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
295 state->index += index_table[nybble];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
296 if ( state->index > 88 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
297 state->index = 88;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
298 } else
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
299 if ( state->index < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
300 state->index = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
301 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
302
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
303 /* Clamp output sample */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
304 if ( state->sample > max_audioval ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
305 state->sample = max_audioval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
306 } else
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
307 if ( state->sample < min_audioval ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
308 state->sample = min_audioval;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
309 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
310 return(state->sample);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
311 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
312
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
313 /* Fill the decode buffer with a channel block of data (8 samples) */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
314 static void Fill_IMA_ADPCM_block(Uint8 *decoded, Uint8 *encoded,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
315 int channel, int numchannels, struct IMA_ADPCM_decodestate *state)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
316 {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
317 int i;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
318 Sint8 nybble;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
319 Sint32 new_sample;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
320
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
321 decoded += (channel * 2);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
322 for ( i=0; i<4; ++i ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
323 nybble = (*encoded)&0x0F;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
324 new_sample = IMA_ADPCM_nibble(state, nybble);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
325 decoded[0] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
326 new_sample >>= 8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
327 decoded[1] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
328 decoded += 2 * numchannels;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
329
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
330 nybble = (*encoded)>>4;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
331 new_sample = IMA_ADPCM_nibble(state, nybble);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
332 decoded[0] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
333 new_sample >>= 8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
334 decoded[1] = new_sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
335 decoded += 2 * numchannels;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
336
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
337 ++encoded;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
338 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
339 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
340
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
341 static int IMA_ADPCM_decode(Uint8 **audio_buf, Uint32 *audio_len)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
342 {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
343 struct IMA_ADPCM_decodestate *state;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
344 Uint8 *freeable, *encoded, *decoded;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
345 Sint32 encoded_len, samplesleft;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
346 int c, channels;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
347
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
348 /* Check to make sure we have enough variables in the state array */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
349 channels = IMA_ADPCM_state.wavefmt.channels;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
350 if ( channels > NELEMS(IMA_ADPCM_state.state) ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
351 SDL_SetError("IMA ADPCM decoder can only handle %d channels",
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
352 NELEMS(IMA_ADPCM_state.state));
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
353 return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
354 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
355 state = IMA_ADPCM_state.state;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
356
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
357 /* Allocate the proper sized output buffer */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
358 encoded_len = *audio_len;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
359 encoded = *audio_buf;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
360 freeable = *audio_buf;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
361 *audio_len = (encoded_len/IMA_ADPCM_state.wavefmt.blockalign) *
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
362 IMA_ADPCM_state.wSamplesPerBlock*
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
363 IMA_ADPCM_state.wavefmt.channels*sizeof(Sint16);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
364 *audio_buf = (Uint8 *)malloc(*audio_len);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
365 if ( *audio_buf == NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
366 SDL_Error(SDL_ENOMEM);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
367 return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
368 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
369 decoded = *audio_buf;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
370
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
371 /* Get ready... Go! */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
372 while ( encoded_len >= IMA_ADPCM_state.wavefmt.blockalign ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
373 /* Grab the initial information for this block */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
374 for ( c=0; c<channels; ++c ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
375 /* Fill the state information for this block */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
376 state[c].sample = ((encoded[1]<<8)|encoded[0]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
377 encoded += 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
378 if ( state[c].sample & 0x8000 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
379 state[c].sample -= 0x10000;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
380 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
381 state[c].index = *encoded++;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
382 /* Reserved byte in buffer header, should be 0 */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
383 if ( *encoded++ != 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
384 /* Uh oh, corrupt data? Buggy code? */;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
385 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
386
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
387 /* Store the initial sample we start with */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
388 decoded[0] = state[c].sample&0xFF;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
389 decoded[1] = state[c].sample>>8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
390 decoded += 2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
391 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
392
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
393 /* Decode and store the other samples in this block */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
394 samplesleft = (IMA_ADPCM_state.wSamplesPerBlock-1)*channels;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
395 while ( samplesleft > 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
396 for ( c=0; c<channels; ++c ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
397 Fill_IMA_ADPCM_block(decoded, encoded,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
398 c, channels, &state[c]);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
399 encoded += 4;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
400 samplesleft -= 8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
401 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
402 decoded += (channels * 8 * 2);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
403 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
404 encoded_len -= IMA_ADPCM_state.wavefmt.blockalign;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
405 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
406 free(freeable);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
407 return(0);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
408 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
409
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
410 SDL_AudioSpec * SDL_LoadWAV_RW (SDL_RWops *src, int freesrc,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
411 SDL_AudioSpec *spec, Uint8 **audio_buf, Uint32 *audio_len)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
412 {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
413 int was_error;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
414 Chunk chunk;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
415 int lenread;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
416 int MS_ADPCM_encoded, IMA_ADPCM_encoded;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
417 int samplesize;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
418
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
419 /* WAV magic header */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
420 Uint32 RIFFchunk;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
421 Uint32 wavelen;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
422 Uint32 WAVEmagic;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
423
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
424 /* FMT chunk */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
425 WaveFMT *format = NULL;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
426
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
427 /* Make sure we are passed a valid data source */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
428 was_error = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
429 if ( src == NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
430 was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
431 goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
432 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
433
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
434 /* Check the magic header */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
435 RIFFchunk = SDL_ReadLE32(src);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
436 wavelen = SDL_ReadLE32(src);
171
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
437 if ( wavelen == WAVE ) { /* The RIFFchunk has already been read */
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
438 WAVEmagic = wavelen;
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
439 wavelen = RIFFchunk;
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
440 RIFFchunk = RIFF;
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
441 } else {
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
442 WAVEmagic = SDL_ReadLE32(src);
02e27b705645 Handle the case where the WAVE magic number was already read in a non-seekable
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
443 }
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
444 if ( (RIFFchunk != RIFF) || (WAVEmagic != WAVE) ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
445 SDL_SetError("Unrecognized file type (not WAVE)");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
446 was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
447 goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
448 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
449
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
450 /* Read the audio data format chunk */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
451 chunk.data = NULL;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
452 do {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
453 if ( chunk.data != NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
454 free(chunk.data);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
455 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
456 lenread = ReadChunk(src, &chunk);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
457 if ( lenread < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
458 was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
459 goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
460 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
461 } while ( (chunk.magic == FACT) || (chunk.magic == LIST) );
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
462
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
463 /* Decode the audio data format */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
464 format = (WaveFMT *)chunk.data;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
465 if ( chunk.magic != FMT ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
466 SDL_SetError("Complex WAVE files not supported");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
467 was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
468 goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
469 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
470 MS_ADPCM_encoded = IMA_ADPCM_encoded = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
471 switch (SDL_SwapLE16(format->encoding)) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
472 case PCM_CODE:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
473 /* We can understand this */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
474 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
475 case MS_ADPCM_CODE:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
476 /* Try to understand this */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
477 if ( InitMS_ADPCM(format) < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
478 was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
479 goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
480 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
481 MS_ADPCM_encoded = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
482 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
483 case IMA_ADPCM_CODE:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
484 /* Try to understand this */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
485 if ( InitIMA_ADPCM(format) < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
486 was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
487 goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
488 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
489 IMA_ADPCM_encoded = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
490 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
491 default:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
492 SDL_SetError("Unknown WAVE data format: 0x%.4x",
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
493 SDL_SwapLE16(format->encoding));
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
494 was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
495 goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
496 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
497 memset(spec, 0, (sizeof *spec));
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
498 spec->freq = SDL_SwapLE32(format->frequency);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
499 switch (SDL_SwapLE16(format->bitspersample)) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
500 case 4:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
501 if ( MS_ADPCM_encoded || IMA_ADPCM_encoded ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
502 spec->format = AUDIO_S16;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
503 } else {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
504 was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
505 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
506 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
507 case 8:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
508 spec->format = AUDIO_U8;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
509 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
510 case 16:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
511 spec->format = AUDIO_S16;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
512 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
513 default:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
514 was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
515 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
516 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
517 if ( was_error ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
518 SDL_SetError("Unknown %d-bit PCM data format",
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
519 SDL_SwapLE16(format->bitspersample));
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
520 goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
521 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
522 spec->channels = (Uint8)SDL_SwapLE16(format->channels);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
523 spec->samples = 4096; /* Good default buffer size */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
524
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
525 /* Read the audio data chunk */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
526 *audio_buf = NULL;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
527 do {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
528 if ( *audio_buf != NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
529 free(*audio_buf);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
530 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
531 lenread = ReadChunk(src, &chunk);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
532 if ( lenread < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
533 was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
534 goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
535 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
536 *audio_len = lenread;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
537 *audio_buf = chunk.data;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
538 } while ( chunk.magic != DATA );
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
539
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
540 if ( MS_ADPCM_encoded ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
541 if ( MS_ADPCM_decode(audio_buf, audio_len) < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
542 was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
543 goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
544 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
545 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
546 if ( IMA_ADPCM_encoded ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
547 if ( IMA_ADPCM_decode(audio_buf, audio_len) < 0 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
548 was_error = 1;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
549 goto done;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
550 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
551 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
552
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
553 /* Don't return a buffer that isn't a multiple of samplesize */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
554 samplesize = ((spec->format & 0xFF)/8)*spec->channels;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
555 *audio_len &= ~(samplesize-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
556
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
557 done:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
558 if ( format != NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
559 free(format);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
560 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
561 if ( freesrc && src ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
562 SDL_RWclose(src);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
563 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
564 if ( was_error ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
565 spec = NULL;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
566 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
567 return(spec);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
568 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
569
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
570 /* Since the WAV memory is allocated in the shared library, it must also
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
571 be freed here. (Necessary under Win32, VC++)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
572 */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
573 void SDL_FreeWAV(Uint8 *audio_buf)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
574 {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
575 if ( audio_buf != NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
576 free(audio_buf);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
577 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
578 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
579
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
580 static int ReadChunk(SDL_RWops *src, Chunk *chunk)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
581 {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
582 chunk->magic = SDL_ReadLE32(src);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
583 chunk->length = SDL_ReadLE32(src);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
584 chunk->data = (Uint8 *)malloc(chunk->length);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
585 if ( chunk->data == NULL ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
586 SDL_Error(SDL_ENOMEM);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
587 return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
588 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
589 if ( SDL_RWread(src, chunk->data, chunk->length, 1) != 1 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
590 SDL_Error(SDL_EFREAD);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
591 free(chunk->data);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
592 return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
593 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
594 return(chunk->length);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
595 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
596
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
597 #endif /* ENABLE_FILE */