libfaad2/mp4.c

   1 /*
   2 ** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
   3 ** Copyright (C) 2003-2004 M. Bakker, Ahead Software AG, http://www.nero.com
   4 **
   5 ** This program is free software; you can redistribute it and/or modify
   6 ** it under the terms of the GNU General Public License as published by
   7 ** the Free Software Foundation; either version 2 of the License, or
   8 ** (at your option) any later version.
   9 **
  10 ** This program is distributed in the hope that it will be useful,
  11 ** but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 ** GNU General Public License for more details.
  14 **
  15 ** You should have received a copy of the GNU General Public License
  16 ** along with this program; if not, write to the Free Software
  17 ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  18 **
  19 ** Any non-GPL usage of this software or parts of this software is strictly
  20 ** forbidden.
  21 **
  22 ** Commercial non-GPL licensing of this software is possible.
  23 ** For more info contact Ahead Software through Mpeg4AAClicense@nero.com.
  24 **
  25 ** $Id: mp4.c,v 1.32 2004/09/04 14:56:28 menno Exp $
  26 **/
  27
  28 #include "common.h"
  29 #include "structs.h"
  30
  31 #include <stdlib.h>
  32
  33 #include "bits.h"
  34 #include "mp4.h"
  35 #include "syntax.h"
  36
  37 /* defines if an object type can be decoded by this library or not */
  38 static uint8_t ObjectTypesTable[32] = {
  39     0, /*  0 NULL */
  40 #ifdef MAIN_DEC
  41     1, /*  1 AAC Main */
  42 #else
  43     0, /*  1 AAC Main */
  44 #endif
  45     1, /*  2 AAC LC */
  46 #ifdef SSR_DEC
  47     1, /*  3 AAC SSR */
  48 #else
  49     0, /*  3 AAC SSR */
  50 #endif
  51 #ifdef LTP_DEC
  52     1, /*  4 AAC LTP */
  53 #else
  54     0, /*  4 AAC LTP */
  55 #endif
  56 #ifdef SBR_DEC
  57     1, /*  5 SBR */
  58 #else
  59     0, /*  5 SBR */
  60 #endif
  61 #ifdef SCALABLE_DEC
  62     1, /*  6 AAC Scalable */
  63 #else
  64     0, /*  6 AAC Scalable */
  65 #endif
  66     0, /*  7 TwinVQ */
  67     0, /*  8 CELP */
  68     0, /*  9 HVXC */
  69     0, /* 10 Reserved */
  70     0, /* 11 Reserved */
  71     0, /* 12 TTSI */
  72     0, /* 13 Main synthetic */
  73     0, /* 14 Wavetable synthesis */
  74     0, /* 15 General MIDI */
  75     0, /* 16 Algorithmic Synthesis and Audio FX */
  76
  77     /* MPEG-4 Version 2 */
  78 #ifdef ERROR_RESILIENCE
  79     1, /* 17 ER AAC LC */
  80     0, /* 18 (Reserved) */
  81 #ifdef LTP_DEC
  82     1, /* 19 ER AAC LTP */
  83 #else
  84     0, /* 19 ER AAC LTP */
  85 #endif
  86 #ifdef SCALABLE_DEC
  87     1, /* 20 ER AAC scalable */
  88 #else
  89     0, /* 20 ER AAC scalable */
  90 #endif
  91     0, /* 21 ER TwinVQ */
  92     0, /* 22 ER BSAC */
  93 #ifdef LD_DEC
  94     1, /* 23 ER AAC LD */
  95 #else
  96     0, /* 23 ER AAC LD */
  97 #endif
  98     0, /* 24 ER CELP */
  99     0, /* 25 ER HVXC */
 100     0, /* 26 ER HILN */
 101     0, /* 27 ER Parametric */
 102 #else /* No ER defined */
 103     0, /* 17 ER AAC LC */
 104     0, /* 18 (Reserved) */
 105     0, /* 19 ER AAC LTP */
 106     0, /* 20 ER AAC scalable */
 107     0, /* 21 ER TwinVQ */
 108     0, /* 22 ER BSAC */
 109     0, /* 23 ER AAC LD */
 110     0, /* 24 ER CELP */
 111     0, /* 25 ER HVXC */
 112     0, /* 26 ER HILN */
 113     0, /* 27 ER Parametric */
 114 #endif
 115     0, /* 28 (Reserved) */
 116     0, /* 29 (Reserved) */
 117     0, /* 30 (Reserved) */
 118     0  /* 31 (Reserved) */
 119 };
 120
 121 /* Table 1.6.1 */
 122 int8_t NEAACDECAPI NeAACDecAudioSpecificConfig(uint8_t *pBuffer,
 123                                                uint32_t buffer_size,
 124                                                mp4AudioSpecificConfig *mp4ASC)
 125 {
 126     return AudioSpecificConfig2(pBuffer, buffer_size, mp4ASC, NULL, 0);
 127 }
 128
 129 int8_t AudioSpecificConfigFromBitfile(bitfile *ld,
 130                             mp4AudioSpecificConfig *mp4ASC,
 131                             program_config *pce, uint32_t buffer_size, uint8_t short_form)
 132 {
 133     int8_t result = 0;
 134     uint32_t startpos = faad_get_processed_bits(ld);
 135 #ifdef SBR_DEC
 136     int8_t bits_to_decode = 0;
 137 #endif
 138
 139     if (mp4ASC == NULL)
 140         return -8;
 141
 142     memset(mp4ASC, 0, sizeof(mp4AudioSpecificConfig));
 143
 144     mp4ASC->objectTypeIndex = (uint8_t)faad_getbits(ld, 5
 145         DEBUGVAR(1,1,"parse_audio_decoder_specific_info(): ObjectTypeIndex"));
 146
 147     mp4ASC->samplingFrequencyIndex = (uint8_t)faad_getbits(ld, 4
 148         DEBUGVAR(1,2,"parse_audio_decoder_specific_info(): SamplingFrequencyIndex"));
 149     if(mp4ASC->samplingFrequencyIndex==0x0f)
 150         faad_getbits(ld, 24);
 151
 152     mp4ASC->channelsConfiguration = (uint8_t)faad_getbits(ld, 4
 153         DEBUGVAR(1,3,"parse_audio_decoder_specific_info(): ChannelsConfiguration"));
 154
 155     mp4ASC->samplingFrequency = get_sample_rate(mp4ASC->samplingFrequencyIndex);
 156
 157     if (ObjectTypesTable[mp4ASC->objectTypeIndex] != 1)
 158     {
 159         return -1;
 160     }
 161
 162     if (mp4ASC->samplingFrequency == 0)
 163     {
 164         return -2;
 165     }
 166
 167     if (mp4ASC->channelsConfiguration > 7)
 168     {
 169         return -3;
 170     }
 171
 172 #if (defined(PS_DEC) || defined(DRM_PS))
 173     /* check if we have a mono file */
 174     if (mp4ASC->channelsConfiguration == 1)
 175     {
 176         /* upMatrix to 2 channels for implicit signalling of PS */
 177         mp4ASC->channelsConfiguration = 2;
 178     }
 179 #endif
 180
 181 #ifdef SBR_DEC
 182     mp4ASC->sbr_present_flag = -1;
 183     if (mp4ASC->objectTypeIndex == 5)
 184     {
 185         uint8_t tmp;
 186
 187         mp4ASC->sbr_present_flag = 1;
 188         tmp = (uint8_t)faad_getbits(ld, 4
 189             DEBUGVAR(1,5,"parse_audio_decoder_specific_info(): extensionSamplingFrequencyIndex"));
 190         /* check for downsampled SBR */
 191         if (tmp == mp4ASC->samplingFrequencyIndex)
 192             mp4ASC->downSampledSBR = 1;
 193         mp4ASC->samplingFrequencyIndex = tmp;
 194         if (mp4ASC->samplingFrequencyIndex == 15)
 195         {
 196             mp4ASC->samplingFrequency = (uint32_t)faad_getbits(ld, 24
 197                 DEBUGVAR(1,6,"parse_audio_decoder_specific_info(): extensionSamplingFrequencyIndex"));
 198         } else {
 199             mp4ASC->samplingFrequency = get_sample_rate(mp4ASC->samplingFrequencyIndex);
 200         }
 201         mp4ASC->objectTypeIndex = (uint8_t)faad_getbits(ld, 5
 202             DEBUGVAR(1,7,"parse_audio_decoder_specific_info(): ObjectTypeIndex"));
 203     }
 204 #endif
 205
 206     /* get GASpecificConfig */
 207     if (mp4ASC->objectTypeIndex == 1 || mp4ASC->objectTypeIndex == 2 ||
 208         mp4ASC->objectTypeIndex == 3 || mp4ASC->objectTypeIndex == 4 ||
 209         mp4ASC->objectTypeIndex == 6 || mp4ASC->objectTypeIndex == 7)
 210     {
 211         result = GASpecificConfig(ld, mp4ASC, pce);
 212
 213 #ifdef ERROR_RESILIENCE
 214     } else if (mp4ASC->objectTypeIndex >= ER_OBJECT_START) { /* ER */
 215         result = GASpecificConfig(ld, mp4ASC, pce);
 216         mp4ASC->epConfig = (uint8_t)faad_getbits(ld, 2
 217             DEBUGVAR(1,143,"parse_audio_decoder_specific_info(): epConfig"));
 218
 219         if (mp4ASC->epConfig != 0)
 220             result = -5;
 221 #endif
 222
 223     } else {
 224         result = -4;
 225     }
 226
 227 #ifdef SSR_DEC
 228     /* shorter frames not allowed for SSR */
 229     if ((mp4ASC->objectTypeIndex == 4) && mp4ASC->frameLengthFlag)
 230         return -6;
 231 #endif
 232
 233
 234 #ifdef SBR_DEC
 235     if(short_form)
 236         bits_to_decode = 0;
 237     else
 238     bits_to_decode = (int8_t)(buffer_size*8 - (startpos-faad_get_processed_bits(ld)));
 239     if ((mp4ASC->objectTypeIndex != 5) && (bits_to_decode >= 16))
 240     {
 241         int16_t syncExtensionType = (int16_t)faad_getbits(ld, 11
 242             DEBUGVAR(1,9,"parse_audio_decoder_specific_info(): syncExtensionType"));
 243
 244         if (syncExtensionType == 0x2b7)
 245         {
 246             mp4ASC->objectTypeIndex = (uint8_t)faad_getbits(ld, 5
 247                 DEBUGVAR(1,10,"parse_audio_decoder_specific_info(): extensionAudioObjectType"));
 248
 249             if (mp4ASC->objectTypeIndex == 5)
 250             {
 251                 mp4ASC->sbr_present_flag = (uint8_t)faad_get1bit(ld
 252                     DEBUGVAR(1,11,"parse_audio_decoder_specific_info(): sbr_present_flag"));
 253
 254                 if (mp4ASC->sbr_present_flag)
 255                 {
 256                     uint8_t tmp;
 257                     tmp = (uint8_t)faad_getbits(ld, 4
 258                         DEBUGVAR(1,12,"parse_audio_decoder_specific_info(): extensionSamplingFrequencyIndex"));
 259
 260                     /* check for downsampled SBR */
 261                     if (tmp == mp4ASC->samplingFrequencyIndex)
 262                         mp4ASC->downSampledSBR = 1;
 263                     mp4ASC->samplingFrequencyIndex = tmp;
 264
 265                     if (mp4ASC->samplingFrequencyIndex == 15)
 266                     {
 267                         mp4ASC->samplingFrequency = (uint32_t)faad_getbits(ld, 24
 268                             DEBUGVAR(1,13,"parse_audio_decoder_specific_info(): extensionSamplingFrequencyIndex"));
 269                     } else {
 270                         mp4ASC->samplingFrequency = get_sample_rate(mp4ASC->samplingFrequencyIndex);
 271                     }
 272                 }
 273             }
 274         }
 275     }
 276
 277     /* no SBR signalled, this could mean either implicit signalling or no SBR in this file */
 278     /* MPEG specification states: assume SBR on files with samplerate <= 24000 Hz */
 279     if (mp4ASC->sbr_present_flag == -1)
 280     {
 281         if (mp4ASC->samplingFrequency <= 24000)
 282         {
 283             mp4ASC->samplingFrequency *= 2;
 284             mp4ASC->forceUpSampling = 1;
 285         } else /* > 24000*/ {
 286             mp4ASC->downSampledSBR = 1;
 287         }
 288     }
 289 #endif
 290
 291     return result;
 292 }
 293
 294 int8_t AudioSpecificConfig2(uint8_t *pBuffer,
 295                             uint32_t buffer_size,
 296                             mp4AudioSpecificConfig *mp4ASC,
 297                             program_config *pce,
 298                             uint8_t short_form)
 299 {
 300     uint8_t ret = 0;
 301     bitfile ld;
 302     faad_initbits(&ld, pBuffer, buffer_size);
 303     faad_byte_align(&ld);
 304     ret = AudioSpecificConfigFromBitfile(&ld, mp4ASC, pce, buffer_size, short_form);
 305     faad_endbits(&ld);
 306     return ret;
 307 }
 308