wp-includes/ID3/module.audio.mp3.php

   1 <?php
   2 /////////////////////////////////////////////////////////////////
   3 /// getID3() by James Heinrich <info@getid3.org>               //
   4 //  available at http://getid3.sourceforge.net                 //
   5 //            or http://www.getid3.org                         //
   6 /////////////////////////////////////////////////////////////////
   7 // See readme.txt for more details                             //
   8 /////////////////////////////////////////////////////////////////
   9 //                                                             //
  10 // module.audio.mp3.php                                        //
  11 // module for analyzing MP3 files                              //
  12 // dependencies: NONE                                          //
  13 //                                                            ///
  14 /////////////////////////////////////////////////////////////////
  15
  16
  17 // number of frames to scan to determine if MPEG-audio sequence is valid
  18 // Lower this number to 5-20 for faster scanning
  19 // Increase this number to 50+ for most accurate detection of valid VBR/CBR
  20 // mpeg-audio streams
  21 define('GETID3_MP3_VALID_CHECK_FRAMES', 35);
  22
  23
  24 class getid3_mp3 extends getid3_handler
  25 {
  26
  27         public $allow_bruteforce = false; // forces getID3() to scan the file byte-by-byte and log all the valid audio frame headers - extremely slow, unrecommended, but may provide data from otherwise-unusuable files
  28
  29         public function Analyze() {
  30                 $info = &$this->getid3->info;
  31
  32                 $initialOffset = $info['avdataoffset'];
  33
  34                 if (!$this->getOnlyMPEGaudioInfo($info['avdataoffset'])) {
  35                         if ($this->allow_bruteforce) {
  36                                 $info['error'][] = 'Rescanning file in BruteForce mode';
  37                                 $this->getOnlyMPEGaudioInfoBruteForce($this->getid3->fp, $info);
  38                         }
  39                 }
  40
  41
  42                 if (isset($info['mpeg']['audio']['bitrate_mode'])) {
  43                         $info['audio']['bitrate_mode'] = strtolower($info['mpeg']['audio']['bitrate_mode']);
  44                 }
  45
  46                 if (((isset($info['id3v2']['headerlength']) && ($info['avdataoffset'] > $info['id3v2']['headerlength'])) || (!isset($info['id3v2']) && ($info['avdataoffset'] > 0) && ($info['avdataoffset'] != $initialOffset)))) {
  47
  48                         $synchoffsetwarning = 'Unknown data before synch ';
  49                         if (isset($info['id3v2']['headerlength'])) {
  50                                 $synchoffsetwarning .= '(ID3v2 header ends at '.$info['id3v2']['headerlength'].', then '.($info['avdataoffset'] - $info['id3v2']['headerlength']).' bytes garbage, ';
  51                         } elseif ($initialOffset > 0) {
  52                                 $synchoffsetwarning .= '(should be at '.$initialOffset.', ';
  53                         } else {
  54                                 $synchoffsetwarning .= '(should be at beginning of file, ';
  55                         }
  56                         $synchoffsetwarning .= 'synch detected at '.$info['avdataoffset'].')';
  57                         if (isset($info['audio']['bitrate_mode']) && ($info['audio']['bitrate_mode'] == 'cbr')) {
  58
  59                                 if (!empty($info['id3v2']['headerlength']) && (($info['avdataoffset'] - $info['id3v2']['headerlength']) == $info['mpeg']['audio']['framelength'])) {
  60
  61                                         $synchoffsetwarning .= '. This is a known problem with some versions of LAME (3.90-3.92) DLL in CBR mode.';
  62                                         $info['audio']['codec'] = 'LAME';
  63                                         $CurrentDataLAMEversionString = 'LAME3.';
  64
  65                                 } elseif (empty($info['id3v2']['headerlength']) && ($info['avdataoffset'] == $info['mpeg']['audio']['framelength'])) {
  66
  67                                         $synchoffsetwarning .= '. This is a known problem with some versions of LAME (3.90 - 3.92) DLL in CBR mode.';
  68                                         $info['audio']['codec'] = 'LAME';
  69                                         $CurrentDataLAMEversionString = 'LAME3.';
  70
  71                                 }
  72
  73                         }
  74                         $info['warning'][] = $synchoffsetwarning;
  75
  76                 }
  77
  78                 if (isset($info['mpeg']['audio']['LAME'])) {
  79                         $info['audio']['codec'] = 'LAME';
  80                         if (!empty($info['mpeg']['audio']['LAME']['long_version'])) {
  81                                 $info['audio']['encoder'] = rtrim($info['mpeg']['audio']['LAME']['long_version'], "\x00");
  82                         } elseif (!empty($info['mpeg']['audio']['LAME']['short_version'])) {
  83                                 $info['audio']['encoder'] = rtrim($info['mpeg']['audio']['LAME']['short_version'], "\x00");
  84                         }
  85                 }
  86
  87                 $CurrentDataLAMEversionString = (!empty($CurrentDataLAMEversionString) ? $CurrentDataLAMEversionString : (isset($info['audio']['encoder']) ? $info['audio']['encoder'] : ''));
  88                 if (!empty($CurrentDataLAMEversionString) && (substr($CurrentDataLAMEversionString, 0, 6) == 'LAME3.') && !preg_match('[0-9\)]', substr($CurrentDataLAMEversionString, -1))) {
  89                         // a version number of LAME that does not end with a number like "LAME3.92"
  90                         // or with a closing parenthesis like "LAME3.88 (alpha)"
  91                         // or a version of LAME with the LAMEtag-not-filled-in-DLL-mode bug (3.90-3.92)
  92
  93                         // not sure what the actual last frame length will be, but will be less than or equal to 1441
  94                         $PossiblyLongerLAMEversion_FrameLength = 1441;
  95
  96                         // Not sure what version of LAME this is - look in padding of last frame for longer version string
  97                         $PossibleLAMEversionStringOffset = $info['avdataend'] - $PossiblyLongerLAMEversion_FrameLength;
  98                         fseek($this->getid3->fp, $PossibleLAMEversionStringOffset);
  99                         $PossiblyLongerLAMEversion_Data = fread($this->getid3->fp, $PossiblyLongerLAMEversion_FrameLength);
 100                         switch (substr($CurrentDataLAMEversionString, -1)) {
 101                                 case 'a':
 102                                 case 'b':
 103                                         // "LAME3.94a" will have a longer version string of "LAME3.94 (alpha)" for example
 104                                         // need to trim off "a" to match longer string
 105                                         $CurrentDataLAMEversionString = substr($CurrentDataLAMEversionString, 0, -1);
 106                                         break;
 107                         }
 108                         if (($PossiblyLongerLAMEversion_String = strstr($PossiblyLongerLAMEversion_Data, $CurrentDataLAMEversionString)) !== false) {
 109                                 if (substr($PossiblyLongerLAMEversion_String, 0, strlen($CurrentDataLAMEversionString)) == $CurrentDataLAMEversionString) {
 110                                         $PossiblyLongerLAMEversion_NewString = substr($PossiblyLongerLAMEversion_String, 0, strspn($PossiblyLongerLAMEversion_String, 'LAME0123456789., (abcdefghijklmnopqrstuvwxyzJFSOND)')); //"LAME3.90.3"  "LAME3.87 (beta 1, Sep 27 2000)" "LAME3.88 (beta)"
 111                                         if (empty($info['audio']['encoder']) || (strlen($PossiblyLongerLAMEversion_NewString) > strlen($info['audio']['encoder']))) {
 112                                                 $info['audio']['encoder'] = $PossiblyLongerLAMEversion_NewString;
 113                                         }
 114                                 }
 115                         }
 116                 }
 117                 if (!empty($info['audio']['encoder'])) {
 118                         $info['audio']['encoder'] = rtrim($info['audio']['encoder'], "\x00 ");
 119                 }
 120
 121                 switch (isset($info['mpeg']['audio']['layer']) ? $info['mpeg']['audio']['layer'] : '') {
 122                         case 1:
 123                         case 2:
 124                                 $info['audio']['dataformat'] = 'mp'.$info['mpeg']['audio']['layer'];
 125                                 break;
 126                 }
 127                 if (isset($info['fileformat']) && ($info['fileformat'] == 'mp3')) {
 128                         switch ($info['audio']['dataformat']) {
 129                                 case 'mp1':
 130                                 case 'mp2':
 131                                 case 'mp3':
 132                                         $info['fileformat'] = $info['audio']['dataformat'];
 133                                         break;
 134
 135                                 default:
 136                                         $info['warning'][] = 'Expecting [audio][dataformat] to be mp1/mp2/mp3 when fileformat == mp3, [audio][dataformat] actually "'.$info['audio']['dataformat'].'"';
 137                                         break;
 138                         }
 139                 }
 140
 141                 if (empty($info['fileformat'])) {
 142                         unset($info['fileformat']);
 143                         unset($info['audio']['bitrate_mode']);
 144                         unset($info['avdataoffset']);
 145                         unset($info['avdataend']);
 146                         return false;
 147                 }
 148
 149                 $info['mime_type']         = 'audio/mpeg';
 150                 $info['audio']['lossless'] = false;
 151
 152                 // Calculate playtime
 153                 if (!isset($info['playtime_seconds']) && isset($info['audio']['bitrate']) && ($info['audio']['bitrate'] > 0)) {
 154                         $info['playtime_seconds'] = ($info['avdataend'] - $info['avdataoffset']) * 8 / $info['audio']['bitrate'];
 155                 }
 156
 157                 $info['audio']['encoder_options'] = $this->GuessEncoderOptions();
 158
 159                 return true;
 160         }
 161
 162
 163         public function GuessEncoderOptions() {
 164                 // shortcuts
 165                 $info = &$this->getid3->info;
 166                 if (!empty($info['mpeg']['audio'])) {
 167                         $thisfile_mpeg_audio = &$info['mpeg']['audio'];
 168                         if (!empty($thisfile_mpeg_audio['LAME'])) {
 169                                 $thisfile_mpeg_audio_lame = &$thisfile_mpeg_audio['LAME'];
 170                         }
 171                 }
 172
 173                 $encoder_options = '';
 174                 static $NamedPresetBitrates = array(16, 24, 40, 56, 112, 128, 160, 192, 256);
 175
 176                 if (isset($thisfile_mpeg_audio['VBR_method']) && ($thisfile_mpeg_audio['VBR_method'] == 'Fraunhofer') && !empty($thisfile_mpeg_audio['VBR_quality'])) {
 177
 178                         $encoder_options = 'VBR q'.$thisfile_mpeg_audio['VBR_quality'];
 179
 180                 } elseif (!empty($thisfile_mpeg_audio_lame['preset_used']) && (!in_array($thisfile_mpeg_audio_lame['preset_used_id'], $NamedPresetBitrates))) {
 181
 182                         $encoder_options = $thisfile_mpeg_audio_lame['preset_used'];
 183
 184                 } elseif (!empty($thisfile_mpeg_audio_lame['vbr_quality'])) {
 185
 186                         static $KnownEncoderValues = array();
 187                         if (empty($KnownEncoderValues)) {
 188
 189                                 //$KnownEncoderValues[abrbitrate_minbitrate][vbr_quality][raw_vbr_method][raw_noise_shaping][raw_stereo_mode][ath_type][lowpass_frequency] = 'preset name';
 190                                 $KnownEncoderValues[0xFF][58][1][1][3][2][20500] = '--alt-preset insane';        // 3.90,   3.90.1, 3.92
 191                                 $KnownEncoderValues[0xFF][58][1][1][3][2][20600] = '--alt-preset insane';        // 3.90.2, 3.90.3, 3.91
 192                                 $KnownEncoderValues[0xFF][57][1][1][3][4][20500] = '--alt-preset insane';        // 3.94,   3.95
 193                                 $KnownEncoderValues['**'][78][3][2][3][2][19500] = '--alt-preset extreme';       // 3.90,   3.90.1, 3.92
 194                                 $KnownEncoderValues['**'][78][3][2][3][2][19600] = '--alt-preset extreme';       // 3.90.2, 3.91
 195                                 $KnownEncoderValues['**'][78][3][1][3][2][19600] = '--alt-preset extreme';       // 3.90.3
 196                                 $KnownEncoderValues['**'][78][4][2][3][2][19500] = '--alt-preset fast extreme';  // 3.90,   3.90.1, 3.92
 197                                 $KnownEncoderValues['**'][78][4][2][3][2][19600] = '--alt-preset fast extreme';  // 3.90.2, 3.90.3, 3.91
 198                                 $KnownEncoderValues['**'][78][3][2][3][4][19000] = '--alt-preset standard';      // 3.90,   3.90.1, 3.90.2, 3.91, 3.92
 199                                 $KnownEncoderValues['**'][78][3][1][3][4][19000] = '--alt-preset standard';      // 3.90.3
 200                                 $KnownEncoderValues['**'][78][4][2][3][4][19000] = '--alt-preset fast standard'; // 3.90,   3.90.1, 3.90.2, 3.91, 3.92
 201                                 $KnownEncoderValues['**'][78][4][1][3][4][19000] = '--alt-preset fast standard'; // 3.90.3
 202                                 $KnownEncoderValues['**'][88][4][1][3][3][19500] = '--r3mix';                    // 3.90,   3.90.1, 3.92
 203                                 $KnownEncoderValues['**'][88][4][1][3][3][19600] = '--r3mix';                    // 3.90.2, 3.90.3, 3.91
 204                                 $KnownEncoderValues['**'][67][4][1][3][4][18000] = '--r3mix';                    // 3.94,   3.95
 205                                 $KnownEncoderValues['**'][68][3][2][3][4][18000] = '--alt-preset medium';        // 3.90.3
 206                                 $KnownEncoderValues['**'][68][4][2][3][4][18000] = '--alt-preset fast medium';   // 3.90.3
 207
 208                                 $KnownEncoderValues[0xFF][99][1][1][1][2][0]     = '--preset studio';            // 3.90,   3.90.1, 3.90.2, 3.91, 3.92
 209                                 $KnownEncoderValues[0xFF][58][2][1][3][2][20600] = '--preset studio';            // 3.90.3, 3.93.1
 210                                 $KnownEncoderValues[0xFF][58][2][1][3][2][20500] = '--preset studio';            // 3.93
 211                                 $KnownEncoderValues[0xFF][57][2][1][3][4][20500] = '--preset studio';            // 3.94,   3.95
 212                                 $KnownEncoderValues[0xC0][88][1][1][1][2][0]     = '--preset cd';                // 3.90,   3.90.1, 3.90.2,   3.91, 3.92
 213                                 $KnownEncoderValues[0xC0][58][2][2][3][2][19600] = '--preset cd';                // 3.90.3, 3.93.1
 214                                 $KnownEncoderValues[0xC0][58][2][2][3][2][19500] = '--preset cd';                // 3.93
 215                                 $KnownEncoderValues[0xC0][57][2][1][3][4][19500] = '--preset cd';                // 3.94,   3.95
 216                                 $KnownEncoderValues[0xA0][78][1][1][3][2][18000] = '--preset hifi';              // 3.90,   3.90.1, 3.90.2,   3.91, 3.92
 217                                 $KnownEncoderValues[0xA0][58][2][2][3][2][18000] = '--preset hifi';              // 3.90.3, 3.93,   3.93.1
 218                                 $KnownEncoderValues[0xA0][57][2][1][3][4][18000] = '--preset hifi';              // 3.94,   3.95
 219                                 $KnownEncoderValues[0x80][67][1][1][3][2][18000] = '--preset tape';              // 3.90,   3.90.1, 3.90.2,   3.91, 3.92
 220                                 $KnownEncoderValues[0x80][67][1][1][3][2][15000] = '--preset radio';             // 3.90,   3.90.1, 3.90.2,   3.91, 3.92
 221                                 $KnownEncoderValues[0x70][67][1][1][3][2][15000] = '--preset fm';                // 3.90,   3.90.1, 3.90.2,   3.91, 3.92
 222                                 $KnownEncoderValues[0x70][58][2][2][3][2][16000] = '--preset tape/radio/fm';     // 3.90.3, 3.93,   3.93.1
 223                                 $KnownEncoderValues[0x70][57][2][1][3][4][16000] = '--preset tape/radio/fm';     // 3.94,   3.95
 224                                 $KnownEncoderValues[0x38][58][2][2][0][2][10000] = '--preset voice';             // 3.90.3, 3.93,   3.93.1
 225                                 $KnownEncoderValues[0x38][57][2][1][0][4][15000] = '--preset voice';             // 3.94,   3.95
 226                                 $KnownEncoderValues[0x38][57][2][1][0][4][16000] = '--preset voice';             // 3.94a14
 227                                 $KnownEncoderValues[0x28][65][1][1][0][2][7500]  = '--preset mw-us';             // 3.90,   3.90.1, 3.92
 228                                 $KnownEncoderValues[0x28][65][1][1][0][2][7600]  = '--preset mw-us';             // 3.90.2, 3.91
 229                                 $KnownEncoderValues[0x28][58][2][2][0][2][7000]  = '--preset mw-us';             // 3.90.3, 3.93,   3.93.1
 230                                 $KnownEncoderValues[0x28][57][2][1][0][4][10500] = '--preset mw-us';             // 3.94,   3.95
 231                                 $KnownEncoderValues[0x28][57][2][1][0][4][11200] = '--preset mw-us';             // 3.94a14
 232                                 $KnownEncoderValues[0x28][57][2][1][0][4][8800]  = '--preset mw-us';             // 3.94a15
 233                                 $KnownEncoderValues[0x18][58][2][2][0][2][4000]  = '--preset phon+/lw/mw-eu/sw'; // 3.90.3, 3.93.1
 234                                 $KnownEncoderValues[0x18][58][2][2][0][2][3900]  = '--preset phon+/lw/mw-eu/sw'; // 3.93
 235                                 $KnownEncoderValues[0x18][57][2][1][0][4][5900]  = '--preset phon+/lw/mw-eu/sw'; // 3.94,   3.95
 236                                 $KnownEncoderValues[0x18][57][2][1][0][4][6200]  = '--preset phon+/lw/mw-eu/sw'; // 3.94a14
 237                                 $KnownEncoderValues[0x18][57][2][1][0][4][3200]  = '--preset phon+/lw/mw-eu/sw'; // 3.94a15
 238                                 $KnownEncoderValues[0x10][58][2][2][0][2][3800]  = '--preset phone';             // 3.90.3, 3.93.1
 239                                 $KnownEncoderValues[0x10][58][2][2][0][2][3700]  = '--preset phone';             // 3.93
 240                                 $KnownEncoderValues[0x10][57][2][1][0][4][5600]  = '--preset phone';             // 3.94,   3.95
 241                         }
 242
 243                         if (isset($KnownEncoderValues[$thisfile_mpeg_audio_lame['raw']['abrbitrate_minbitrate']][$thisfile_mpeg_audio_lame['vbr_quality']][$thisfile_mpeg_audio_lame['raw']['vbr_method']][$thisfile_mpeg_audio_lame['raw']['noise_shaping']][$thisfile_mpeg_audio_lame['raw']['stereo_mode']][$thisfile_mpeg_audio_lame['ath_type']][$thisfile_mpeg_audio_lame['lowpass_frequency']])) {
 244
 245                                 $encoder_options = $KnownEncoderValues[$thisfile_mpeg_audio_lame['raw']['abrbitrate_minbitrate']][$thisfile_mpeg_audio_lame['vbr_quality']][$thisfile_mpeg_audio_lame['raw']['vbr_method']][$thisfile_mpeg_audio_lame['raw']['noise_shaping']][$thisfile_mpeg_audio_lame['raw']['stereo_mode']][$thisfile_mpeg_audio_lame['ath_type']][$thisfile_mpeg_audio_lame['lowpass_frequency']];
 246
 247                         } elseif (isset($KnownEncoderValues['**'][$thisfile_mpeg_audio_lame['vbr_quality']][$thisfile_mpeg_audio_lame['raw']['vbr_method']][$thisfile_mpeg_audio_lame['raw']['noise_shaping']][$thisfile_mpeg_audio_lame['raw']['stereo_mode']][$thisfile_mpeg_audio_lame['ath_type']][$thisfile_mpeg_audio_lame['lowpass_frequency']])) {
 248
 249                                 $encoder_options = $KnownEncoderValues['**'][$thisfile_mpeg_audio_lame['vbr_quality']][$thisfile_mpeg_audio_lame['raw']['vbr_method']][$thisfile_mpeg_audio_lame['raw']['noise_shaping']][$thisfile_mpeg_audio_lame['raw']['stereo_mode']][$thisfile_mpeg_audio_lame['ath_type']][$thisfile_mpeg_audio_lame['lowpass_frequency']];
 250
 251                         } elseif ($info['audio']['bitrate_mode'] == 'vbr') {
 252
 253                                 // http://gabriel.mp3-tech.org/mp3infotag.html
 254                                 // int    Quality = (100 - 10 * gfp->VBR_q - gfp->quality)h
 255
 256
 257                                 $LAME_V_value = 10 - ceil($thisfile_mpeg_audio_lame['vbr_quality'] / 10);
 258                                 $LAME_q_value = 100 - $thisfile_mpeg_audio_lame['vbr_quality'] - ($LAME_V_value * 10);
 259                                 $encoder_options = '-V'.$LAME_V_value.' -q'.$LAME_q_value;
 260
 261                         } elseif ($info['audio']['bitrate_mode'] == 'cbr') {
 262
 263                                 $encoder_options = strtoupper($info['audio']['bitrate_mode']).ceil($info['audio']['bitrate'] / 1000);
 264
 265                         } else {
 266
 267                                 $encoder_options = strtoupper($info['audio']['bitrate_mode']);
 268
 269                         }
 270
 271                 } elseif (!empty($thisfile_mpeg_audio_lame['bitrate_abr'])) {
 272
 273                         $encoder_options = 'ABR'.$thisfile_mpeg_audio_lame['bitrate_abr'];
 274
 275                 } elseif (!empty($info['audio']['bitrate'])) {
 276
 277                         if ($info['audio']['bitrate_mode'] == 'cbr') {
 278                                 $encoder_options = strtoupper($info['audio']['bitrate_mode']).ceil($info['audio']['bitrate'] / 1000);
 279                         } else {
 280                                 $encoder_options = strtoupper($info['audio']['bitrate_mode']);
 281                         }
 282
 283                 }
 284                 if (!empty($thisfile_mpeg_audio_lame['bitrate_min'])) {
 285                         $encoder_options .= ' -b'.$thisfile_mpeg_audio_lame['bitrate_min'];
 286                 }
 287
 288                 if (!empty($thisfile_mpeg_audio_lame['encoding_flags']['nogap_prev']) || !empty($thisfile_mpeg_audio_lame['encoding_flags']['nogap_next'])) {
 289                         $encoder_options .= ' --nogap';
 290                 }
 291
 292                 if (!empty($thisfile_mpeg_audio_lame['lowpass_frequency'])) {
 293                         $ExplodedOptions = explode(' ', $encoder_options, 4);
 294                         if ($ExplodedOptions[0] == '--r3mix') {
 295                                 $ExplodedOptions[1] = 'r3mix';
 296                         }
 297                         switch ($ExplodedOptions[0]) {
 298                                 case '--preset':
 299                                 case '--alt-preset':
 300                                 case '--r3mix':
 301                                         if ($ExplodedOptions[1] == 'fast') {
 302                                                 $ExplodedOptions[1] .= ' '.$ExplodedOptions[2];
 303                                         }
 304                                         switch ($ExplodedOptions[1]) {
 305                                                 case 'portable':
 306                                                 case 'medium':
 307                                                 case 'standard':
 308                                                 case 'extreme':
 309                                                 case 'insane':
 310                                                 case 'fast portable':
 311                                                 case 'fast medium':
 312                                                 case 'fast standard':
 313                                                 case 'fast extreme':
 314                                                 case 'fast insane':
 315                                                 case 'r3mix':
 316                                                         static $ExpectedLowpass = array(
 317                                                                         'insane|20500'        => 20500,
 318                                                                         'insane|20600'        => 20600,  // 3.90.2, 3.90.3, 3.91
 319                                                                         'medium|18000'        => 18000,
 320                                                                         'fast medium|18000'   => 18000,
 321                                                                         'extreme|19500'       => 19500,  // 3.90,   3.90.1, 3.92, 3.95
 322                                                                         'extreme|19600'       => 19600,  // 3.90.2, 3.90.3, 3.91, 3.93.1
 323                                                                         'fast extreme|19500'  => 19500,  // 3.90,   3.90.1, 3.92, 3.95
 324                                                                         'fast extreme|19600'  => 19600,  // 3.90.2, 3.90.3, 3.91, 3.93.1
 325                                                                         'standard|19000'      => 19000,
 326                                                                         'fast standard|19000' => 19000,
 327                                                                         'r3mix|19500'         => 19500,  // 3.90,   3.90.1, 3.92
 328                                                                         'r3mix|19600'         => 19600,  // 3.90.2, 3.90.3, 3.91
 329                                                                         'r3mix|18000'         => 18000,  // 3.94,   3.95
 330                                                                 );
 331                                                         if (!isset($ExpectedLowpass[$ExplodedOptions[1].'|'.$thisfile_mpeg_audio_lame['lowpass_frequency']]) && ($thisfile_mpeg_audio_lame['lowpass_frequency'] < 22050) && (round($thisfile_mpeg_audio_lame['lowpass_frequency'] / 1000) < round($thisfile_mpeg_audio['sample_rate'] / 2000))) {
 332                                                                 $encoder_options .= ' --lowpass '.$thisfile_mpeg_audio_lame['lowpass_frequency'];
 333                                                         }
 334                                                         break;
 335
 336                                                 default:
 337                                                         break;
 338                                         }
 339                                         break;
 340                         }
 341                 }
 342
 343                 if (isset($thisfile_mpeg_audio_lame['raw']['source_sample_freq'])) {
 344                         if (($thisfile_mpeg_audio['sample_rate'] == 44100) && ($thisfile_mpeg_audio_lame['raw']['source_sample_freq'] != 1)) {
 345                                 $encoder_options .= ' --resample 44100';
 346                         } elseif (($thisfile_mpeg_audio['sample_rate'] == 48000) && ($thisfile_mpeg_audio_lame['raw']['source_sample_freq'] != 2)) {
 347                                 $encoder_options .= ' --resample 48000';
 348                         } elseif ($thisfile_mpeg_audio['sample_rate'] < 44100) {
 349                                 switch ($thisfile_mpeg_audio_lame['raw']['source_sample_freq']) {
 350                                         case 0: // <= 32000
 351                                                 // may or may not be same as source frequency - ignore
 352                                                 break;
 353                                         case 1: // 44100
 354                                         case 2: // 48000
 355                                         case 3: // 48000+
 356                                                 $ExplodedOptions = explode(' ', $encoder_options, 4);
 357                                                 switch ($ExplodedOptions[0]) {
 358                                                         case '--preset':
 359                                                         case '--alt-preset':
 360                                                                 switch ($ExplodedOptions[1]) {
 361                                                                         case 'fast':
 362                                                                         case 'portable':
 363                                                                         case 'medium':
 364                                                                         case 'standard':
 365                                                                         case 'extreme':
 366                                                                         case 'insane':
 367                                                                                 $encoder_options .= ' --resample '.$thisfile_mpeg_audio['sample_rate'];
 368                                                                                 break;
 369
 370                                                                         default:
 371                                                                                 static $ExpectedResampledRate = array(
 372                                                                                                 'phon+/lw/mw-eu/sw|16000' => 16000,
 373                                                                                                 'mw-us|24000'             => 24000, // 3.95
 374                                                                                                 'mw-us|32000'             => 32000, // 3.93
 375                                                                                                 'mw-us|16000'             => 16000, // 3.92
 376                                                                                                 'phone|16000'             => 16000,
 377                                                                                                 'phone|11025'             => 11025, // 3.94a15
 378                                                                                                 'radio|32000'             => 32000, // 3.94a15
 379                                                                                                 'fm/radio|32000'          => 32000, // 3.92
 380                                                                                                 'fm|32000'                => 32000, // 3.90
 381                                                                                                 'voice|32000'             => 32000);
 382                                                                                 if (!isset($ExpectedResampledRate[$ExplodedOptions[1].'|'.$thisfile_mpeg_audio['sample_rate']])) {
 383                                                                                         $encoder_options .= ' --resample '.$thisfile_mpeg_audio['sample_rate'];
 384                                                                                 }
 385                                                                                 break;
 386                                                                 }
 387                                                                 break;
 388
 389                                                         case '--r3mix':
 390                                                         default:
 391                                                                 $encoder_options .= ' --resample '.$thisfile_mpeg_audio['sample_rate'];
 392                                                                 break;
 393                                                 }
 394                                                 break;
 395                                 }
 396                         }
 397                 }
 398                 if (empty($encoder_options) && !empty($info['audio']['bitrate']) && !empty($info['audio']['bitrate_mode'])) {
 399                         //$encoder_options = strtoupper($info['audio']['bitrate_mode']).ceil($info['audio']['bitrate'] / 1000);
 400                         $encoder_options = strtoupper($info['audio']['bitrate_mode']);
 401                 }
 402
 403                 return $encoder_options;
 404         }
 405
 406
 407         public function decodeMPEGaudioHeader($offset, &$info, $recursivesearch=true, $ScanAsCBR=false, $FastMPEGheaderScan=false) {
 408                 static $MPEGaudioVersionLookup;
 409                 static $MPEGaudioLayerLookup;
 410                 static $MPEGaudioBitrateLookup;
 411                 static $MPEGaudioFrequencyLookup;
 412                 static $MPEGaudioChannelModeLookup;
 413                 static $MPEGaudioModeExtensionLookup;
 414                 static $MPEGaudioEmphasisLookup;
 415                 if (empty($MPEGaudioVersionLookup)) {
 416                         $MPEGaudioVersionLookup       = self::MPEGaudioVersionArray();
 417                         $MPEGaudioLayerLookup         = self::MPEGaudioLayerArray();
 418                         $MPEGaudioBitrateLookup       = self::MPEGaudioBitrateArray();
 419                         $MPEGaudioFrequencyLookup     = self::MPEGaudioFrequencyArray();
 420                         $MPEGaudioChannelModeLookup   = self::MPEGaudioChannelModeArray();
 421                         $MPEGaudioModeExtensionLookup = self::MPEGaudioModeExtensionArray();
 422                         $MPEGaudioEmphasisLookup      = self::MPEGaudioEmphasisArray();
 423                 }
 424
 425                 if (fseek($this->getid3->fp, $offset, SEEK_SET) != 0) {
 426                         $info['error'][] = 'decodeMPEGaudioHeader() failed to seek to next offset at '.$offset;
 427                         return false;
 428                 }
 429                 //$headerstring = fread($this->getid3->fp, 1441); // worst-case max length = 32kHz @ 320kbps layer 3 = 1441 bytes/frame
 430                 $headerstring = fread($this->getid3->fp, 226); // LAME header at offset 36 + 190 bytes of Xing/LAME data
 431
 432                 // MP3 audio frame structure:
 433                 // $aa $aa $aa $aa [$bb $bb] $cc...
 434                 // where $aa..$aa is the four-byte mpeg-audio header (below)
 435                 // $bb $bb is the optional 2-byte CRC
 436                 // and $cc... is the audio data
 437
 438                 $head4 = substr($headerstring, 0, 4);
 439
 440                 static $MPEGaudioHeaderDecodeCache = array();
 441                 if (isset($MPEGaudioHeaderDecodeCache[$head4])) {
 442                         $MPEGheaderRawArray = $MPEGaudioHeaderDecodeCache[$head4];
 443                 } else {
 444                         $MPEGheaderRawArray = self::MPEGaudioHeaderDecode($head4);
 445                         $MPEGaudioHeaderDecodeCache[$head4] = $MPEGheaderRawArray;
 446                 }
 447
 448                 static $MPEGaudioHeaderValidCache = array();
 449                 if (!isset($MPEGaudioHeaderValidCache[$head4])) { // Not in cache
 450                         //$MPEGaudioHeaderValidCache[$head4] = self::MPEGaudioHeaderValid($MPEGheaderRawArray, false, true);  // allow badly-formatted freeformat (from LAME 3.90 - 3.93.1)
 451                         $MPEGaudioHeaderValidCache[$head4] = self::MPEGaudioHeaderValid($MPEGheaderRawArray, false, false);
 452                 }
 453
 454                 // shortcut
 455                 if (!isset($info['mpeg']['audio'])) {
 456                         $info['mpeg']['audio'] = array();
 457                 }
 458                 $thisfile_mpeg_audio = &$info['mpeg']['audio'];
 459
 460
 461                 if ($MPEGaudioHeaderValidCache[$head4]) {
 462                         $thisfile_mpeg_audio['raw'] = $MPEGheaderRawArray;
 463                 } else {
 464                         $info['error'][] = 'Invalid MPEG audio header ('.getid3_lib::PrintHexBytes($head4).') at offset '.$offset;
 465                         return false;
 466                 }
 467
 468                 if (!$FastMPEGheaderScan) {
 469                         $thisfile_mpeg_audio['version']       = $MPEGaudioVersionLookup[$thisfile_mpeg_audio['raw']['version']];
 470                         $thisfile_mpeg_audio['layer']         = $MPEGaudioLayerLookup[$thisfile_mpeg_audio['raw']['layer']];
 471
 472                         $thisfile_mpeg_audio['channelmode']   = $MPEGaudioChannelModeLookup[$thisfile_mpeg_audio['raw']['channelmode']];
 473                         $thisfile_mpeg_audio['channels']      = (($thisfile_mpeg_audio['channelmode'] == 'mono') ? 1 : 2);
 474                         $thisfile_mpeg_audio['sample_rate']   = $MPEGaudioFrequencyLookup[$thisfile_mpeg_audio['version']][$thisfile_mpeg_audio['raw']['sample_rate']];
 475                         $thisfile_mpeg_audio['protection']    = !$thisfile_mpeg_audio['raw']['protection'];
 476                         $thisfile_mpeg_audio['private']       = (bool) $thisfile_mpeg_audio['raw']['private'];
 477                         $thisfile_mpeg_audio['modeextension'] = $MPEGaudioModeExtensionLookup[$thisfile_mpeg_audio['layer']][$thisfile_mpeg_audio['raw']['modeextension']];
 478                         $thisfile_mpeg_audio['copyright']     = (bool) $thisfile_mpeg_audio['raw']['copyright'];
 479                         $thisfile_mpeg_audio['original']      = (bool) $thisfile_mpeg_audio['raw']['original'];
 480                         $thisfile_mpeg_audio['emphasis']      = $MPEGaudioEmphasisLookup[$thisfile_mpeg_audio['raw']['emphasis']];
 481
 482                         $info['audio']['channels']    = $thisfile_mpeg_audio['channels'];
 483                         $info['audio']['sample_rate'] = $thisfile_mpeg_audio['sample_rate'];
 484
 485                         if ($thisfile_mpeg_audio['protection']) {
 486                                 $thisfile_mpeg_audio['crc'] = getid3_lib::BigEndian2Int(substr($headerstring, 4, 2));
 487                         }
 488                 }
 489
 490                 if ($thisfile_mpeg_audio['raw']['bitrate'] == 15) {
 491                         // http://www.hydrogenaudio.org/?act=ST&f=16&t=9682&st=0
 492                         $info['warning'][] = 'Invalid bitrate index (15), this is a known bug in free-format MP3s encoded by LAME v3.90 - 3.93.1';
 493                         $thisfile_mpeg_audio['raw']['bitrate'] = 0;
 494                 }
 495                 $thisfile_mpeg_audio['padding'] = (bool) $thisfile_mpeg_audio['raw']['padding'];
 496                 $thisfile_mpeg_audio['bitrate'] = $MPEGaudioBitrateLookup[$thisfile_mpeg_audio['version']][$thisfile_mpeg_audio['layer']][$thisfile_mpeg_audio['raw']['bitrate']];
 497
 498                 if (($thisfile_mpeg_audio['bitrate'] == 'free') && ($offset == $info['avdataoffset'])) {
 499                         // only skip multiple frame check if free-format bitstream found at beginning of file
 500                         // otherwise is quite possibly simply corrupted data
 501                         $recursivesearch = false;
 502                 }
 503
 504                 // For Layer 2 there are some combinations of bitrate and mode which are not allowed.
 505                 if (!$FastMPEGheaderScan && ($thisfile_mpeg_audio['layer'] == '2')) {
 506
 507                         $info['audio']['dataformat'] = 'mp2';
 508                         switch ($thisfile_mpeg_audio['channelmode']) {
 509
 510                                 case 'mono':
 511                                         if (($thisfile_mpeg_audio['bitrate'] == 'free') || ($thisfile_mpeg_audio['bitrate'] <= 192000)) {
 512                                                 // these are ok
 513                                         } else {
 514                                                 $info['error'][] = $thisfile_mpeg_audio['bitrate'].'kbps not allowed in Layer 2, '.$thisfile_mpeg_audio['channelmode'].'.';
 515                                                 return false;
 516                                         }
 517                                         break;
 518
 519                                 case 'stereo':
 520                                 case 'joint stereo':
 521                                 case 'dual channel':
 522                                         if (($thisfile_mpeg_audio['bitrate'] == 'free') || ($thisfile_mpeg_audio['bitrate'] == 64000) || ($thisfile_mpeg_audio['bitrate'] >= 96000)) {
 523                                                 // these are ok
 524                                         } else {
 525                                                 $info['error'][] = intval(round($thisfile_mpeg_audio['bitrate'] / 1000)).'kbps not allowed in Layer 2, '.$thisfile_mpeg_audio['channelmode'].'.';
 526                                                 return false;
 527                                         }
 528                                         break;
 529
 530                         }
 531
 532                 }
 533
 534
 535                 if ($info['audio']['sample_rate'] > 0) {
 536                         $thisfile_mpeg_audio['framelength'] = self::MPEGaudioFrameLength($thisfile_mpeg_audio['bitrate'], $thisfile_mpeg_audio['version'], $thisfile_mpeg_audio['layer'], (int) $thisfile_mpeg_audio['padding'], $info['audio']['sample_rate']);
 537                 }
 538
 539                 $nextframetestoffset = $offset + 1;
 540                 if ($thisfile_mpeg_audio['bitrate'] != 'free') {
 541
 542                         $info['audio']['bitrate'] = $thisfile_mpeg_audio['bitrate'];
 543
 544                         if (isset($thisfile_mpeg_audio['framelength'])) {
 545                                 $nextframetestoffset = $offset + $thisfile_mpeg_audio['framelength'];
 546                         } else {
 547                                 $info['error'][] = 'Frame at offset('.$offset.') is has an invalid frame length.';
 548                                 return false;
 549                         }
 550
 551                 }
 552
 553                 $ExpectedNumberOfAudioBytes = 0;
 554
 555                 ////////////////////////////////////////////////////////////////////////////////////
 556                 // Variable-bitrate headers
 557
 558                 if (substr($headerstring, 4 + 32, 4) == 'VBRI') {
 559                         // Fraunhofer VBR header is hardcoded 'VBRI' at offset 0x24 (36)
 560                         // specs taken from http://minnie.tuhs.org/pipermail/mp3encoder/2001-January/001800.html
 561
 562                         $thisfile_mpeg_audio['bitrate_mode'] = 'vbr';
 563                         $thisfile_mpeg_audio['VBR_method']   = 'Fraunhofer';
 564                         $info['audio']['codec']                = 'Fraunhofer';
 565
 566                         $SideInfoData = substr($headerstring, 4 + 2, 32);
 567
 568                         $FraunhoferVBROffset = 36;
 569
 570                         $thisfile_mpeg_audio['VBR_encoder_version']     = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset +  4, 2)); // VbriVersion
 571                         $thisfile_mpeg_audio['VBR_encoder_delay']       = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset +  6, 2)); // VbriDelay
 572                         $thisfile_mpeg_audio['VBR_quality']             = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset +  8, 2)); // VbriQuality
 573                         $thisfile_mpeg_audio['VBR_bytes']               = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 10, 4)); // VbriStreamBytes
 574                         $thisfile_mpeg_audio['VBR_frames']              = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 14, 4)); // VbriStreamFrames
 575                         $thisfile_mpeg_audio['VBR_seek_offsets']        = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 18, 2)); // VbriTableSize
 576                         $thisfile_mpeg_audio['VBR_seek_scale']          = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 20, 2)); // VbriTableScale
 577                         $thisfile_mpeg_audio['VBR_entry_bytes']         = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 22, 2)); // VbriEntryBytes
 578                         $thisfile_mpeg_audio['VBR_entry_frames']        = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset + 24, 2)); // VbriEntryFrames
 579
 580                         $ExpectedNumberOfAudioBytes = $thisfile_mpeg_audio['VBR_bytes'];
 581
 582                         $previousbyteoffset = $offset;
 583                         for ($i = 0; $i < $thisfile_mpeg_audio['VBR_seek_offsets']; $i++) {
 584                                 $Fraunhofer_OffsetN = getid3_lib::BigEndian2Int(substr($headerstring, $FraunhoferVBROffset, $thisfile_mpeg_audio['VBR_entry_bytes']));
 585                                 $FraunhoferVBROffset += $thisfile_mpeg_audio['VBR_entry_bytes'];
 586                                 $thisfile_mpeg_audio['VBR_offsets_relative'][$i] = ($Fraunhofer_OffsetN * $thisfile_mpeg_audio['VBR_seek_scale']);
 587                                 $thisfile_mpeg_audio['VBR_offsets_absolute'][$i] = ($Fraunhofer_OffsetN * $thisfile_mpeg_audio['VBR_seek_scale']) + $previousbyteoffset;
 588                                 $previousbyteoffset += $Fraunhofer_OffsetN;
 589                         }
 590
 591
 592                 } else {
 593
 594                         // Xing VBR header is hardcoded 'Xing' at a offset 0x0D (13), 0x15 (21) or 0x24 (36)
 595                         // depending on MPEG layer and number of channels
 596
 597                         $VBRidOffset = self::XingVBRidOffset($thisfile_mpeg_audio['version'], $thisfile_mpeg_audio['channelmode']);
 598                         $SideInfoData = substr($headerstring, 4 + 2, $VBRidOffset - 4);
 599
 600                         if ((substr($headerstring, $VBRidOffset, strlen('Xing')) == 'Xing') || (substr($headerstring, $VBRidOffset, strlen('Info')) == 'Info')) {
 601                                 // 'Xing' is traditional Xing VBR frame
 602                                 // 'Info' is LAME-encoded CBR (This was done to avoid CBR files to be recognized as traditional Xing VBR files by some decoders.)
 603                                 // 'Info' *can* legally be used to specify a VBR file as well, however.
 604
 605                                 // http://www.multiweb.cz/twoinches/MP3inside.htm
 606                                 //00..03 = "Xing" or "Info"
 607                                 //04..07 = Flags:
 608                                 //  0x01  Frames Flag     set if value for number of frames in file is stored
 609                                 //  0x02  Bytes Flag      set if value for filesize in bytes is stored
 610                                 //  0x04  TOC Flag        set if values for TOC are stored
 611                                 //  0x08  VBR Scale Flag  set if values for VBR scale is stored
 612                                 //08..11  Frames: Number of frames in file (including the first Xing/Info one)
 613                                 //12..15  Bytes:  File length in Bytes
 614                                 //16..115  TOC (Table of Contents):
 615                                 //  Contains of 100 indexes (one Byte length) for easier lookup in file. Approximately solves problem with moving inside file.
 616                                 //  Each Byte has a value according this formula:
 617                                 //  (TOC[i] / 256) * fileLenInBytes
 618                                 //  So if song lasts eg. 240 sec. and you want to jump to 60. sec. (and file is 5 000 000 Bytes length) you can use:
 619                                 //  TOC[(60/240)*100] = TOC[25]
 620                                 //  and corresponding Byte in file is then approximately at:
 621                                 //  (TOC[25]/256) * 5000000
 622                                 //116..119  VBR Scale
 623
 624
 625                                 // should be safe to leave this at 'vbr' and let it be overriden to 'cbr' if a CBR preset/mode is used by LAME
 626 //                              if (substr($headerstring, $VBRidOffset, strlen('Info')) == 'Xing') {
 627                                         $thisfile_mpeg_audio['bitrate_mode'] = 'vbr';
 628                                         $thisfile_mpeg_audio['VBR_method']   = 'Xing';
 629 //                              } else {
 630 //                                      $ScanAsCBR = true;
 631 //                                      $thisfile_mpeg_audio['bitrate_mode'] = 'cbr';
 632 //                              }
 633
 634                                 $thisfile_mpeg_audio['xing_flags_raw'] = getid3_lib::BigEndian2Int(substr($headerstring, $VBRidOffset + 4, 4));
 635
 636                                 $thisfile_mpeg_audio['xing_flags']['frames']    = (bool) ($thisfile_mpeg_audio['xing_flags_raw'] & 0x00000001);
 637                                 $thisfile_mpeg_audio['xing_flags']['bytes']     = (bool) ($thisfile_mpeg_audio['xing_flags_raw'] & 0x00000002);
 638                                 $thisfile_mpeg_audio['xing_flags']['toc']       = (bool) ($thisfile_mpeg_audio['xing_flags_raw'] & 0x00000004);
 639                                 $thisfile_mpeg_audio['xing_flags']['vbr_scale'] = (bool) ($thisfile_mpeg_audio['xing_flags_raw'] & 0x00000008);
 640
 641                                 if ($thisfile_mpeg_audio['xing_flags']['frames']) {
 642                                         $thisfile_mpeg_audio['VBR_frames'] = getid3_lib::BigEndian2Int(substr($headerstring, $VBRidOffset +  8, 4));
 643                                         //$thisfile_mpeg_audio['VBR_frames']--; // don't count header Xing/Info frame
 644                                 }
 645                                 if ($thisfile_mpeg_audio['xing_flags']['bytes']) {
 646                                         $thisfile_mpeg_audio['VBR_bytes']  = getid3_lib::BigEndian2Int(substr($headerstring, $VBRidOffset + 12, 4));
 647                                 }
 648
 649                                 //if (($thisfile_mpeg_audio['bitrate'] == 'free') && !empty($thisfile_mpeg_audio['VBR_frames']) && !empty($thisfile_mpeg_audio['VBR_bytes'])) {
 650                                 if (!empty($thisfile_mpeg_audio['VBR_frames']) && !empty($thisfile_mpeg_audio['VBR_bytes'])) {
 651
 652                                         $framelengthfloat = $thisfile_mpeg_audio['VBR_bytes'] / $thisfile_mpeg_audio['VBR_frames'];
 653
 654                                         if ($thisfile_mpeg_audio['layer'] == '1') {
 655                                                 // BitRate = (((FrameLengthInBytes / 4) - Padding) * SampleRate) / 12
 656                                                 //$info['audio']['bitrate'] = ((($framelengthfloat / 4) - intval($thisfile_mpeg_audio['padding'])) * $thisfile_mpeg_audio['sample_rate']) / 12;
 657                                                 $info['audio']['bitrate'] = ($framelengthfloat / 4) * $thisfile_mpeg_audio['sample_rate'] * (2 / $info['audio']['channels']) / 12;
 658                                         } else {
 659                                                 // Bitrate = ((FrameLengthInBytes - Padding) * SampleRate) / 144
 660                                                 //$info['audio']['bitrate'] = (($framelengthfloat - intval($thisfile_mpeg_audio['padding'])) * $thisfile_mpeg_audio['sample_rate']) / 144;
 661                                                 $info['audio']['bitrate'] = $framelengthfloat * $thisfile_mpeg_audio['sample_rate'] * (2 / $info['audio']['channels']) / 144;
 662                                         }
 663                                         $thisfile_mpeg_audio['framelength'] = floor($framelengthfloat);
 664                                 }
 665
 666                                 if ($thisfile_mpeg_audio['xing_flags']['toc']) {
 667                                         $LAMEtocData = substr($headerstring, $VBRidOffset + 16, 100);
 668                                         for ($i = 0; $i < 100; $i++) {
 669                                                 $thisfile_mpeg_audio['toc'][$i] = ord($LAMEtocData{$i});
 670                                         }
 671                                 }
 672                                 if ($thisfile_mpeg_audio['xing_flags']['vbr_scale']) {
 673                                         $thisfile_mpeg_audio['VBR_scale'] = getid3_lib::BigEndian2Int(substr($headerstring, $VBRidOffset + 116, 4));
 674                                 }
 675
 676
 677                                 // http://gabriel.mp3-tech.org/mp3infotag.html
 678                                 if (substr($headerstring, $VBRidOffset + 120, 4) == 'LAME') {
 679
 680                                         // shortcut
 681                                         $thisfile_mpeg_audio['LAME'] = array();
 682                                         $thisfile_mpeg_audio_lame    = &$thisfile_mpeg_audio['LAME'];
 683
 684
 685                                         $thisfile_mpeg_audio_lame['long_version']  = substr($headerstring, $VBRidOffset + 120, 20);
 686                                         $thisfile_mpeg_audio_lame['short_version'] = substr($thisfile_mpeg_audio_lame['long_version'], 0, 9);
 687
 688                                         if ($thisfile_mpeg_audio_lame['short_version'] >= 'LAME3.90') {
 689
 690                                                 // extra 11 chars are not part of version string when LAMEtag present
 691                                                 unset($thisfile_mpeg_audio_lame['long_version']);
 692
 693                                                 // It the LAME tag was only introduced in LAME v3.90
 694                                                 // http://www.hydrogenaudio.org/?act=ST&f=15&t=9933
 695
 696                                                 // Offsets of various bytes in http://gabriel.mp3-tech.org/mp3infotag.html
 697                                                 // are assuming a 'Xing' identifier offset of 0x24, which is the case for
 698                                                 // MPEG-1 non-mono, but not for other combinations
 699                                                 $LAMEtagOffsetContant = $VBRidOffset - 0x24;
 700
 701                                                 // shortcuts
 702                                                 $thisfile_mpeg_audio_lame['RGAD']    = array('track'=>array(), 'album'=>array());
 703                                                 $thisfile_mpeg_audio_lame_RGAD       = &$thisfile_mpeg_audio_lame['RGAD'];
 704                                                 $thisfile_mpeg_audio_lame_RGAD_track = &$thisfile_mpeg_audio_lame_RGAD['track'];
 705                                                 $thisfile_mpeg_audio_lame_RGAD_album = &$thisfile_mpeg_audio_lame_RGAD['album'];
 706                                                 $thisfile_mpeg_audio_lame['raw'] = array();
 707                                                 $thisfile_mpeg_audio_lame_raw    = &$thisfile_mpeg_audio_lame['raw'];
 708
 709                                                 // byte $9B  VBR Quality
 710                                                 // This field is there to indicate a quality level, although the scale was not precised in the original Xing specifications.
 711                                                 // Actually overwrites original Xing bytes
 712                                                 unset($thisfile_mpeg_audio['VBR_scale']);
 713                                                 $thisfile_mpeg_audio_lame['vbr_quality'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0x9B, 1));
 714
 715                                                 // bytes $9C-$A4  Encoder short VersionString
 716                                                 $thisfile_mpeg_audio_lame['short_version'] = substr($headerstring, $LAMEtagOffsetContant + 0x9C, 9);
 717
 718                                                 // byte $A5  Info Tag revision + VBR method
 719                                                 $LAMEtagRevisionVBRmethod = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xA5, 1));
 720
 721                                                 $thisfile_mpeg_audio_lame['tag_revision']   = ($LAMEtagRevisionVBRmethod & 0xF0) >> 4;
 722                                                 $thisfile_mpeg_audio_lame_raw['vbr_method'] =  $LAMEtagRevisionVBRmethod & 0x0F;
 723                                                 $thisfile_mpeg_audio_lame['vbr_method']     = self::LAMEvbrMethodLookup($thisfile_mpeg_audio_lame_raw['vbr_method']);
 724                                                 $thisfile_mpeg_audio['bitrate_mode']        = substr($thisfile_mpeg_audio_lame['vbr_method'], 0, 3); // usually either 'cbr' or 'vbr', but truncates 'vbr-old / vbr-rh' to 'vbr'
 725
 726                                                 // byte $A6  Lowpass filter value
 727                                                 $thisfile_mpeg_audio_lame['lowpass_frequency'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xA6, 1)) * 100;
 728
 729                                                 // bytes $A7-$AE  Replay Gain
 730                                                 // http://privatewww.essex.ac.uk/~djmrob/replaygain/rg_data_format.html
 731                                                 // bytes $A7-$AA : 32 bit floating point "Peak signal amplitude"
 732                                                 if ($thisfile_mpeg_audio_lame['short_version'] >= 'LAME3.94b') {
 733                                                         // LAME 3.94a16 and later - 9.23 fixed point
 734                                                         // ie 0x0059E2EE / (2^23) = 5890798 / 8388608 = 0.7022378444671630859375
 735                                                         $thisfile_mpeg_audio_lame_RGAD['peak_amplitude'] = (float) ((getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xA7, 4))) / 8388608);
 736                                                 } else {
 737                                                         // LAME 3.94a15 and earlier - 32-bit floating point
 738                                                         // Actually 3.94a16 will fall in here too and be WRONG, but is hard to detect 3.94a16 vs 3.94a15
 739                                                         $thisfile_mpeg_audio_lame_RGAD['peak_amplitude'] = getid3_lib::LittleEndian2Float(substr($headerstring, $LAMEtagOffsetContant + 0xA7, 4));
 740                                                 }
 741                                                 if ($thisfile_mpeg_audio_lame_RGAD['peak_amplitude'] == 0) {
 742                                                         unset($thisfile_mpeg_audio_lame_RGAD['peak_amplitude']);
 743                                                 } else {
 744                                                         $thisfile_mpeg_audio_lame_RGAD['peak_db'] = getid3_lib::RGADamplitude2dB($thisfile_mpeg_audio_lame_RGAD['peak_amplitude']);
 745                                                 }
 746
 747                                                 $thisfile_mpeg_audio_lame_raw['RGAD_track']      =   getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xAB, 2));
 748                                                 $thisfile_mpeg_audio_lame_raw['RGAD_album']      =   getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xAD, 2));
 749
 750
 751                                                 if ($thisfile_mpeg_audio_lame_raw['RGAD_track'] != 0) {
 752
 753                                                         $thisfile_mpeg_audio_lame_RGAD_track['raw']['name']        = ($thisfile_mpeg_audio_lame_raw['RGAD_track'] & 0xE000) >> 13;
 754                                                         $thisfile_mpeg_audio_lame_RGAD_track['raw']['originator']  = ($thisfile_mpeg_audio_lame_raw['RGAD_track'] & 0x1C00) >> 10;
 755                                                         $thisfile_mpeg_audio_lame_RGAD_track['raw']['sign_bit']    = ($thisfile_mpeg_audio_lame_raw['RGAD_track'] & 0x0200) >> 9;
 756                                                         $thisfile_mpeg_audio_lame_RGAD_track['raw']['gain_adjust'] =  $thisfile_mpeg_audio_lame_raw['RGAD_track'] & 0x01FF;
 757                                                         $thisfile_mpeg_audio_lame_RGAD_track['name']       = getid3_lib::RGADnameLookup($thisfile_mpeg_audio_lame_RGAD_track['raw']['name']);
 758                                                         $thisfile_mpeg_audio_lame_RGAD_track['originator'] = getid3_lib::RGADoriginatorLookup($thisfile_mpeg_audio_lame_RGAD_track['raw']['originator']);
 759                                                         $thisfile_mpeg_audio_lame_RGAD_track['gain_db']    = getid3_lib::RGADadjustmentLookup($thisfile_mpeg_audio_lame_RGAD_track['raw']['gain_adjust'], $thisfile_mpeg_audio_lame_RGAD_track['raw']['sign_bit']);
 760
 761                                                         if (!empty($thisfile_mpeg_audio_lame_RGAD['peak_amplitude'])) {
 762                                                                 $info['replay_gain']['track']['peak']   = $thisfile_mpeg_audio_lame_RGAD['peak_amplitude'];
 763                                                         }
 764                                                         $info['replay_gain']['track']['originator'] = $thisfile_mpeg_audio_lame_RGAD_track['originator'];
 765                                                         $info['replay_gain']['track']['adjustment'] = $thisfile_mpeg_audio_lame_RGAD_track['gain_db'];
 766                                                 } else {
 767                                                         unset($thisfile_mpeg_audio_lame_RGAD['track']);
 768                                                 }
 769                                                 if ($thisfile_mpeg_audio_lame_raw['RGAD_album'] != 0) {
 770
 771                                                         $thisfile_mpeg_audio_lame_RGAD_album['raw']['name']        = ($thisfile_mpeg_audio_lame_raw['RGAD_album'] & 0xE000) >> 13;
 772                                                         $thisfile_mpeg_audio_lame_RGAD_album['raw']['originator']  = ($thisfile_mpeg_audio_lame_raw['RGAD_album'] & 0x1C00) >> 10;
 773                                                         $thisfile_mpeg_audio_lame_RGAD_album['raw']['sign_bit']    = ($thisfile_mpeg_audio_lame_raw['RGAD_album'] & 0x0200) >> 9;
 774                                                         $thisfile_mpeg_audio_lame_RGAD_album['raw']['gain_adjust'] = $thisfile_mpeg_audio_lame_raw['RGAD_album'] & 0x01FF;
 775                                                         $thisfile_mpeg_audio_lame_RGAD_album['name']       = getid3_lib::RGADnameLookup($thisfile_mpeg_audio_lame_RGAD_album['raw']['name']);
 776                                                         $thisfile_mpeg_audio_lame_RGAD_album['originator'] = getid3_lib::RGADoriginatorLookup($thisfile_mpeg_audio_lame_RGAD_album['raw']['originator']);
 777                                                         $thisfile_mpeg_audio_lame_RGAD_album['gain_db']    = getid3_lib::RGADadjustmentLookup($thisfile_mpeg_audio_lame_RGAD_album['raw']['gain_adjust'], $thisfile_mpeg_audio_lame_RGAD_album['raw']['sign_bit']);
 778
 779                                                         if (!empty($thisfile_mpeg_audio_lame_RGAD['peak_amplitude'])) {
 780                                                                 $info['replay_gain']['album']['peak']   = $thisfile_mpeg_audio_lame_RGAD['peak_amplitude'];
 781                                                         }
 782                                                         $info['replay_gain']['album']['originator'] = $thisfile_mpeg_audio_lame_RGAD_album['originator'];
 783                                                         $info['replay_gain']['album']['adjustment'] = $thisfile_mpeg_audio_lame_RGAD_album['gain_db'];
 784                                                 } else {
 785                                                         unset($thisfile_mpeg_audio_lame_RGAD['album']);
 786                                                 }
 787                                                 if (empty($thisfile_mpeg_audio_lame_RGAD)) {
 788                                                         unset($thisfile_mpeg_audio_lame['RGAD']);
 789                                                 }
 790
 791
 792                                                 // byte $AF  Encoding flags + ATH Type
 793                                                 $EncodingFlagsATHtype = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xAF, 1));
 794                                                 $thisfile_mpeg_audio_lame['encoding_flags']['nspsytune']   = (bool) ($EncodingFlagsATHtype & 0x10);
 795                                                 $thisfile_mpeg_audio_lame['encoding_flags']['nssafejoint'] = (bool) ($EncodingFlagsATHtype & 0x20);
 796                                                 $thisfile_mpeg_audio_lame['encoding_flags']['nogap_next']  = (bool) ($EncodingFlagsATHtype & 0x40);
 797                                                 $thisfile_mpeg_audio_lame['encoding_flags']['nogap_prev']  = (bool) ($EncodingFlagsATHtype & 0x80);
 798                                                 $thisfile_mpeg_audio_lame['ath_type']                      =         $EncodingFlagsATHtype & 0x0F;
 799
 800                                                 // byte $B0  if ABR {specified bitrate} else {minimal bitrate}
 801                                                 $thisfile_mpeg_audio_lame['raw']['abrbitrate_minbitrate'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xB0, 1));
 802                                                 if ($thisfile_mpeg_audio_lame_raw['vbr_method'] == 2) { // Average BitRate (ABR)
 803                                                         $thisfile_mpeg_audio_lame['bitrate_abr'] = $thisfile_mpeg_audio_lame['raw']['abrbitrate_minbitrate'];
 804                                                 } elseif ($thisfile_mpeg_audio_lame_raw['vbr_method'] == 1) { // Constant BitRate (CBR)
 805                                                         // ignore
 806                                                 } elseif ($thisfile_mpeg_audio_lame['raw']['abrbitrate_minbitrate'] > 0) { // Variable BitRate (VBR) - minimum bitrate
 807                                                         $thisfile_mpeg_audio_lame['bitrate_min'] = $thisfile_mpeg_audio_lame['raw']['abrbitrate_minbitrate'];
 808                                                 }
 809
 810                                                 // bytes $B1-$B3  Encoder delays
 811                                                 $EncoderDelays = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xB1, 3));
 812                                                 $thisfile_mpeg_audio_lame['encoder_delay'] = ($EncoderDelays & 0xFFF000) >> 12;
 813                                                 $thisfile_mpeg_audio_lame['end_padding']   =  $EncoderDelays & 0x000FFF;
 814
 815                                                 // byte $B4  Misc
 816                                                 $MiscByte = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xB4, 1));
 817                                                 $thisfile_mpeg_audio_lame_raw['noise_shaping']       = ($MiscByte & 0x03);
 818                                                 $thisfile_mpeg_audio_lame_raw['stereo_mode']         = ($MiscByte & 0x1C) >> 2;
 819                                                 $thisfile_mpeg_audio_lame_raw['not_optimal_quality'] = ($MiscByte & 0x20) >> 5;
 820                                                 $thisfile_mpeg_audio_lame_raw['source_sample_freq']  = ($MiscByte & 0xC0) >> 6;
 821                                                 $thisfile_mpeg_audio_lame['noise_shaping']       = $thisfile_mpeg_audio_lame_raw['noise_shaping'];
 822                                                 $thisfile_mpeg_audio_lame['stereo_mode']         = self::LAMEmiscStereoModeLookup($thisfile_mpeg_audio_lame_raw['stereo_mode']);
 823                                                 $thisfile_mpeg_audio_lame['not_optimal_quality'] = (bool) $thisfile_mpeg_audio_lame_raw['not_optimal_quality'];
 824                                                 $thisfile_mpeg_audio_lame['source_sample_freq']  = self::LAMEmiscSourceSampleFrequencyLookup($thisfile_mpeg_audio_lame_raw['source_sample_freq']);
 825
 826                                                 // byte $B5  MP3 Gain
 827                                                 $thisfile_mpeg_audio_lame_raw['mp3_gain'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xB5, 1), false, true);
 828                                                 $thisfile_mpeg_audio_lame['mp3_gain_db']     = (getid3_lib::RGADamplitude2dB(2) / 4) * $thisfile_mpeg_audio_lame_raw['mp3_gain'];
 829                                                 $thisfile_mpeg_audio_lame['mp3_gain_factor'] = pow(2, ($thisfile_mpeg_audio_lame['mp3_gain_db'] / 6));
 830
 831                                                 // bytes $B6-$B7  Preset and surround info
 832                                                 $PresetSurroundBytes = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xB6, 2));
 833                                                 // Reserved                                                    = ($PresetSurroundBytes & 0xC000);
 834                                                 $thisfile_mpeg_audio_lame_raw['surround_info'] = ($PresetSurroundBytes & 0x3800);
 835                                                 $thisfile_mpeg_audio_lame['surround_info']     = self::LAMEsurroundInfoLookup($thisfile_mpeg_audio_lame_raw['surround_info']);
 836                                                 $thisfile_mpeg_audio_lame['preset_used_id']    = ($PresetSurroundBytes & 0x07FF);
 837                                                 $thisfile_mpeg_audio_lame['preset_used']       = self::LAMEpresetUsedLookup($thisfile_mpeg_audio_lame);
 838                                                 if (!empty($thisfile_mpeg_audio_lame['preset_used_id']) && empty($thisfile_mpeg_audio_lame['preset_used'])) {
 839                                                         $info['warning'][] = 'Unknown LAME preset used ('.$thisfile_mpeg_audio_lame['preset_used_id'].') - please report to info@getid3.org';
 840                                                 }
 841                                                 if (($thisfile_mpeg_audio_lame['short_version'] == 'LAME3.90.') && !empty($thisfile_mpeg_audio_lame['preset_used_id'])) {
 842                                                         // this may change if 3.90.4 ever comes out
 843                                                         $thisfile_mpeg_audio_lame['short_version'] = 'LAME3.90.3';
 844                                                 }
 845
 846                                                 // bytes $B8-$BB  MusicLength
 847                                                 $thisfile_mpeg_audio_lame['audio_bytes'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xB8, 4));
 848                                                 $ExpectedNumberOfAudioBytes = (($thisfile_mpeg_audio_lame['audio_bytes'] > 0) ? $thisfile_mpeg_audio_lame['audio_bytes'] : $thisfile_mpeg_audio['VBR_bytes']);
 849
 850                                                 // bytes $BC-$BD  MusicCRC
 851                                                 $thisfile_mpeg_audio_lame['music_crc']    = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xBC, 2));
 852
 853                                                 // bytes $BE-$BF  CRC-16 of Info Tag
 854                                                 $thisfile_mpeg_audio_lame['lame_tag_crc'] = getid3_lib::BigEndian2Int(substr($headerstring, $LAMEtagOffsetContant + 0xBE, 2));
 855
 856
 857                                                 // LAME CBR
 858                                                 if ($thisfile_mpeg_audio_lame_raw['vbr_method'] == 1) {
 859
 860                                                         $thisfile_mpeg_audio['bitrate_mode'] = 'cbr';
 861                                                         $thisfile_mpeg_audio['bitrate'] = self::ClosestStandardMP3Bitrate($thisfile_mpeg_audio['bitrate']);
 862                                                         $info['audio']['bitrate'] = $thisfile_mpeg_audio['bitrate'];
 863                                                         //if (empty($thisfile_mpeg_audio['bitrate']) || (!empty($thisfile_mpeg_audio_lame['bitrate_min']) && ($thisfile_mpeg_audio_lame['bitrate_min'] != 255))) {
 864                                                         //      $thisfile_mpeg_audio['bitrate'] = $thisfile_mpeg_audio_lame['bitrate_min'];
 865                                                         //}
 866
 867                                                 }
 868
 869                                         }
 870                                 }
 871
 872                         } else {
 873
 874                                 // not Fraunhofer or Xing VBR methods, most likely CBR (but could be VBR with no header)
 875                                 $thisfile_mpeg_audio['bitrate_mode'] = 'cbr';
 876                                 if ($recursivesearch) {
 877                                         $thisfile_mpeg_audio['bitrate_mode'] = 'vbr';
 878                                         if ($this->RecursiveFrameScanning($offset, $nextframetestoffset, true)) {
 879                                                 $recursivesearch = false;
 880                                                 $thisfile_mpeg_audio['bitrate_mode'] = 'cbr';
 881                                         }
 882                                         if ($thisfile_mpeg_audio['bitrate_mode'] == 'vbr') {
 883                                                 $info['warning'][] = 'VBR file with no VBR header. Bitrate values calculated from actual frame bitrates.';
 884                                         }
 885                                 }
 886
 887                         }
 888
 889                 }
 890
 891                 if (($ExpectedNumberOfAudioBytes > 0) && ($ExpectedNumberOfAudioBytes != ($info['avdataend'] - $info['avdataoffset']))) {
 892                         if ($ExpectedNumberOfAudioBytes > ($info['avdataend'] - $info['avdataoffset'])) {
 893                                 if (isset($info['fileformat']) && ($info['fileformat'] == 'riff')) {
 894                                         // ignore, audio data is broken into chunks so will always be data "missing"
 895                                 } elseif (($ExpectedNumberOfAudioBytes - ($info['avdataend'] - $info['avdataoffset'])) == 1) {
 896                                         $info['warning'][] = 'Last byte of data truncated (this is a known bug in Meracl ID3 Tag Writer before v1.3.5)';
 897                                 } else {
 898                                         $info['warning'][] = 'Probable truncated file: expecting '.$ExpectedNumberOfAudioBytes.' bytes of audio data, only found '.($info['avdataend'] - $info['avdataoffset']).' (short by '.($ExpectedNumberOfAudioBytes - ($info['avdataend'] - $info['avdataoffset'])).' bytes)';
 899                                 }
 900                         } else {
 901                                 if ((($info['avdataend'] - $info['avdataoffset']) - $ExpectedNumberOfAudioBytes) == 1) {
 902                                 //      $prenullbytefileoffset = ftell($this->getid3->fp);
 903                                 //      fseek($this->getid3->fp, $info['avdataend'], SEEK_SET);
 904                                 //      $PossibleNullByte = fread($this->getid3->fp, 1);
 905                                 //      fseek($this->getid3->fp, $prenullbytefileoffset, SEEK_SET);
 906                                 //      if ($PossibleNullByte === "\x00") {
 907                                                 $info['avdataend']--;
 908                                 //              $info['warning'][] = 'Extra null byte at end of MP3 data assumed to be RIFF padding and therefore ignored';
 909                                 //      } else {
 910                                 //              $info['warning'][] = 'Too much data in file: expecting '.$ExpectedNumberOfAudioBytes.' bytes of audio data, found '.($info['avdataend'] - $info['avdataoffset']).' ('.(($info['avdataend'] - $info['avdataoffset']) - $ExpectedNumberOfAudioBytes).' bytes too many)';
 911                                 //      }
 912                                 } else {
 913                                         $info['warning'][] = 'Too much data in file: expecting '.$ExpectedNumberOfAudioBytes.' bytes of audio data, found '.($info['avdataend'] - $info['avdataoffset']).' ('.(($info['avdataend'] - $info['avdataoffset']) - $ExpectedNumberOfAudioBytes).' bytes too many)';
 914                                 }
 915                         }
 916                 }
 917
 918                 if (($thisfile_mpeg_audio['bitrate'] == 'free') && empty($info['audio']['bitrate'])) {
 919                         if (($offset == $info['avdataoffset']) && empty($thisfile_mpeg_audio['VBR_frames'])) {
 920                                 $framebytelength = $this->FreeFormatFrameLength($offset, true);
 921                                 if ($framebytelength > 0) {
 922                                         $thisfile_mpeg_audio['framelength'] = $framebytelength;
 923                                         if ($thisfile_mpeg_audio['layer'] == '1') {
 924                                                 // BitRate = (((FrameLengthInBytes / 4) - Padding) * SampleRate) / 12
 925                                                 $info['audio']['bitrate'] = ((($framebytelength / 4) - intval($thisfile_mpeg_audio['padding'])) * $thisfile_mpeg_audio['sample_rate']) / 12;
 926                                         } else {
 927                                                 // Bitrate = ((FrameLengthInBytes - Padding) * SampleRate) / 144
 928                                                 $info['audio']['bitrate'] = (($framebytelength - intval($thisfile_mpeg_audio['padding'])) * $thisfile_mpeg_audio['sample_rate']) / 144;
 929                                         }
 930                                 } else {
 931                                         $info['error'][] = 'Error calculating frame length of free-format MP3 without Xing/LAME header';
 932                                 }
 933                         }
 934                 }
 935
 936                 if (isset($thisfile_mpeg_audio['VBR_frames']) ? $thisfile_mpeg_audio['VBR_frames'] : '') {
 937                         switch ($thisfile_mpeg_audio['bitrate_mode']) {
 938                                 case 'vbr':
 939                                 case 'abr':
 940                                         $bytes_per_frame = 1152;
 941                                         if (($thisfile_mpeg_audio['version'] == '1') && ($thisfile_mpeg_audio['layer'] == 1)) {
 942                                                 $bytes_per_frame = 384;
 943                                         } elseif ((($thisfile_mpeg_audio['version'] == '2') || ($thisfile_mpeg_audio['version'] == '2.5')) && ($thisfile_mpeg_audio['layer'] == 3)) {
 944                                                 $bytes_per_frame = 576;
 945                                         }
 946                                         $thisfile_mpeg_audio['VBR_bitrate'] = (isset($thisfile_mpeg_audio['VBR_bytes']) ? (($thisfile_mpeg_audio['VBR_bytes'] / $thisfile_mpeg_audio['VBR_frames']) * 8) * ($info['audio']['sample_rate'] / $bytes_per_frame) : 0);
 947                                         if ($thisfile_mpeg_audio['VBR_bitrate'] > 0) {
 948                                                 $info['audio']['bitrate']         = $thisfile_mpeg_audio['VBR_bitrate'];
 949                                                 $thisfile_mpeg_audio['bitrate'] = $thisfile_mpeg_audio['VBR_bitrate']; // to avoid confusion
 950                                         }
 951                                         break;
 952                         }
 953                 }
 954
 955                 // End variable-bitrate headers
 956                 ////////////////////////////////////////////////////////////////////////////////////
 957
 958                 if ($recursivesearch) {
 959
 960                         if (!$this->RecursiveFrameScanning($offset, $nextframetestoffset, $ScanAsCBR)) {
 961                                 return false;
 962                         }
 963
 964                 }
 965
 966
 967                 //if (false) {
 968                 //    // experimental side info parsing section - not returning anything useful yet
 969                 //
 970                 //    $SideInfoBitstream = getid3_lib::BigEndian2Bin($SideInfoData);
 971                 //    $SideInfoOffset = 0;
 972                 //
 973                 //    if ($thisfile_mpeg_audio['version'] == '1') {
 974                 //        if ($thisfile_mpeg_audio['channelmode'] == 'mono') {
 975                 //            // MPEG-1 (mono)
 976                 //            $thisfile_mpeg_audio['side_info']['main_data_begin'] = substr($SideInfoBitstream, $SideInfoOffset, 9);
 977                 //            $SideInfoOffset += 9;
 978                 //            $SideInfoOffset += 5;
 979                 //        } else {
 980                 //            // MPEG-1 (stereo, joint-stereo, dual-channel)
 981                 //            $thisfile_mpeg_audio['side_info']['main_data_begin'] = substr($SideInfoBitstream, $SideInfoOffset, 9);
 982                 //            $SideInfoOffset += 9;
 983                 //            $SideInfoOffset += 3;
 984                 //        }
 985                 //    } else { // 2 or 2.5
 986                 //        if ($thisfile_mpeg_audio['channelmode'] == 'mono') {
 987                 //            // MPEG-2, MPEG-2.5 (mono)
 988                 //            $thisfile_mpeg_audio['side_info']['main_data_begin'] = substr($SideInfoBitstream, $SideInfoOffset, 8);
 989                 //            $SideInfoOffset += 8;
 990                 //            $SideInfoOffset += 1;
 991                 //        } else {
 992                 //            // MPEG-2, MPEG-2.5 (stereo, joint-stereo, dual-channel)
 993                 //            $thisfile_mpeg_audio['side_info']['main_data_begin'] = substr($SideInfoBitstream, $SideInfoOffset, 8);
 994                 //            $SideInfoOffset += 8;
 995                 //            $SideInfoOffset += 2;
 996                 //        }
 997                 //    }
 998                 //
 999                 //    if ($thisfile_mpeg_audio['version'] == '1') {
1000                 //        for ($channel = 0; $channel < $info['audio']['channels']; $channel++) {
1001                 //            for ($scfsi_band = 0; $scfsi_band < 4; $scfsi_band++) {
1002                 //                $thisfile_mpeg_audio['scfsi'][$channel][$scfsi_band] = substr($SideInfoBitstream, $SideInfoOffset, 1);
1003                 //                $SideInfoOffset += 2;
1004                 //            }
1005                 //        }
1006                 //    }
1007                 //    for ($granule = 0; $granule < (($thisfile_mpeg_audio['version'] == '1') ? 2 : 1); $granule++) {
1008                 //        for ($channel = 0; $channel < $info['audio']['channels']; $channel++) {
1009                 //            $thisfile_mpeg_audio['part2_3_length'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 12);
1010                 //            $SideInfoOffset += 12;
1011                 //            $thisfile_mpeg_audio['big_values'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 9);
1012                 //            $SideInfoOffset += 9;
1013                 //            $thisfile_mpeg_audio['global_gain'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 8);
1014                 //            $SideInfoOffset += 8;
1015                 //            if ($thisfile_mpeg_audio['version'] == '1') {
1016                 //                $thisfile_mpeg_audio['scalefac_compress'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 4);
1017                 //                $SideInfoOffset += 4;
1018                 //            } else {
1019                 //                $thisfile_mpeg_audio['scalefac_compress'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 9);
1020                 //                $SideInfoOffset += 9;
1021                 //            }
1022                 //            $thisfile_mpeg_audio['window_switching_flag'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 1);
1023                 //            $SideInfoOffset += 1;
1024                 //
1025                 //            if ($thisfile_mpeg_audio['window_switching_flag'][$granule][$channel] == '1') {
1026                 //
1027                 //                $thisfile_mpeg_audio['block_type'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 2);
1028                 //                $SideInfoOffset += 2;
1029                 //                $thisfile_mpeg_audio['mixed_block_flag'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 1);
1030                 //                $SideInfoOffset += 1;
1031                 //
1032                 //                for ($region = 0; $region < 2; $region++) {
1033                 //                    $thisfile_mpeg_audio['table_select'][$granule][$channel][$region] = substr($SideInfoBitstream, $SideInfoOffset, 5);
1034                 //                    $SideInfoOffset += 5;
1035                 //                }
1036                 //                $thisfile_mpeg_audio['table_select'][$granule][$channel][2] = 0;
1037                 //
1038                 //                for ($window = 0; $window < 3; $window++) {
1039                 //                    $thisfile_mpeg_audio['subblock_gain'][$granule][$channel][$window] = substr($SideInfoBitstream, $SideInfoOffset, 3);
1040                 //                    $SideInfoOffset += 3;
1041                 //                }
1042                 //
1043                 //            } else {
1044                 //
1045                 //                for ($region = 0; $region < 3; $region++) {
1046                 //                    $thisfile_mpeg_audio['table_select'][$granule][$channel][$region] = substr($SideInfoBitstream, $SideInfoOffset, 5);
1047                 //                    $SideInfoOffset += 5;
1048                 //                }
1049                 //
1050                 //                $thisfile_mpeg_audio['region0_count'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 4);
1051                 //                $SideInfoOffset += 4;
1052                 //                $thisfile_mpeg_audio['region1_count'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 3);
1053                 //                $SideInfoOffset += 3;
1054                 //                $thisfile_mpeg_audio['block_type'][$granule][$channel] = 0;
1055                 //            }
1056                 //
1057                 //            if ($thisfile_mpeg_audio['version'] == '1') {
1058                 //                $thisfile_mpeg_audio['preflag'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 1);
1059                 //                $SideInfoOffset += 1;
1060                 //            }
1061                 //            $thisfile_mpeg_audio['scalefac_scale'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 1);
1062                 //            $SideInfoOffset += 1;
1063                 //            $thisfile_mpeg_audio['count1table_select'][$granule][$channel] = substr($SideInfoBitstream, $SideInfoOffset, 1);
1064                 //            $SideInfoOffset += 1;
1065                 //        }
1066                 //    }
1067                 //}
1068
1069                 return true;
1070         }
1071
1072         public function RecursiveFrameScanning(&$offset, &$nextframetestoffset, $ScanAsCBR) {
1073                 $info = &$this->getid3->info;
1074                 $firstframetestarray = array('error'=>'', 'warning'=>'', 'avdataend'=>$info['avdataend'], 'avdataoffset'=>$info['avdataoffset']);
1075                 $this->decodeMPEGaudioHeader($offset, $firstframetestarray, false);
1076
1077                 for ($i = 0; $i < GETID3_MP3_VALID_CHECK_FRAMES; $i++) {
1078                         // check next GETID3_MP3_VALID_CHECK_FRAMES frames for validity, to make sure we haven't run across a false synch
1079                         if (($nextframetestoffset + 4) >= $info['avdataend']) {
1080                                 // end of file
1081                                 return true;
1082                         }
1083
1084                         $nextframetestarray = array('error'=>'', 'warning'=>'', 'avdataend'=>$info['avdataend'], 'avdataoffset'=>$info['avdataoffset']);
1085                         if ($this->decodeMPEGaudioHeader($nextframetestoffset, $nextframetestarray, false)) {
1086                                 if ($ScanAsCBR) {
1087                                         // force CBR mode, used for trying to pick out invalid audio streams with valid(?) VBR headers, or VBR streams with no VBR header
1088                                         if (!isset($nextframetestarray['mpeg']['audio']['bitrate']) || !isset($firstframetestarray['mpeg']['audio']['bitrate']) || ($nextframetestarray['mpeg']['audio']['bitrate'] != $firstframetestarray['mpeg']['audio']['bitrate'])) {
1089                                                 return false;
1090                                         }
1091                                 }
1092
1093
1094                                 // next frame is OK, get ready to check the one after that
1095                                 if (isset($nextframetestarray['mpeg']['audio']['framelength']) && ($nextframetestarray['mpeg']['audio']['framelength'] > 0)) {
1096                                         $nextframetestoffset += $nextframetestarray['mpeg']['audio']['framelength'];
1097                                 } else {
1098                                         $info['error'][] = 'Frame at offset ('.$offset.') is has an invalid frame length.';
1099                                         return false;
1100                                 }
1101
1102                         } elseif (!empty($firstframetestarray['mpeg']['audio']['framelength']) && (($nextframetestoffset + $firstframetestarray['mpeg']['audio']['framelength']) > $info['avdataend'])) {
1103
1104                                 // it's not the end of the file, but there's not enough data left for another frame, so assume it's garbage/padding and return OK
1105                                 return true;
1106
1107                         } else {
1108
1109                                 // next frame is not valid, note the error and fail, so scanning can contiue for a valid frame sequence
1110                                 $info['warning'][] = 'Frame at offset ('.$offset.') is valid, but the next one at ('.$nextframetestoffset.') is not.';
1111
1112                                 return false;
1113                         }
1114                 }
1115                 return true;
1116         }
1117
1118         public function FreeFormatFrameLength($offset, $deepscan=false) {
1119                 $info = &$this->getid3->info;
1120
1121                 fseek($this->getid3->fp, $offset, SEEK_SET);
1122                 $MPEGaudioData = fread($this->getid3->fp, 32768);
1123
1124                 $SyncPattern1 = substr($MPEGaudioData, 0, 4);
1125                 // may be different pattern due to padding
1126                 $SyncPattern2 = $SyncPattern1{0}.$SyncPattern1{1}.chr(ord($SyncPattern1{2}) | 0x02).$SyncPattern1{3};
1127                 if ($SyncPattern2 === $SyncPattern1) {
1128                         $SyncPattern2 = $SyncPattern1{0}.$SyncPattern1{1}.chr(ord($SyncPattern1{2}) & 0xFD).$SyncPattern1{3};
1129                 }
1130
1131                 $framelength = false;
1132                 $framelength1 = strpos($MPEGaudioData, $SyncPattern1, 4);
1133                 $framelength2 = strpos($MPEGaudioData, $SyncPattern2, 4);
1134                 if ($framelength1 > 4) {
1135                         $framelength = $framelength1;
1136                 }
1137                 if (($framelength2 > 4) && ($framelength2 < $framelength1)) {
1138                         $framelength = $framelength2;
1139                 }
1140                 if (!$framelength) {
1141
1142                         // LAME 3.88 has a different value for modeextension on the first frame vs the rest
1143                         $framelength1 = strpos($MPEGaudioData, substr($SyncPattern1, 0, 3), 4);
1144                         $framelength2 = strpos($MPEGaudioData, substr($SyncPattern2, 0, 3), 4);
1145
1146                         if ($framelength1 > 4) {
1147                                 $framelength = $framelength1;
1148                         }
1149                         if (($framelength2 > 4) && ($framelength2 < $framelength1)) {
1150                                 $framelength = $framelength2;
1151                         }
1152                         if (!$framelength) {
1153                                 $info['error'][] = 'Cannot find next free-format synch pattern ('.getid3_lib::PrintHexBytes($SyncPattern1).' or '.getid3_lib::PrintHexBytes($SyncPattern2).') after offset '.$offset;
1154                                 return false;
1155                         } else {
1156                                 $info['warning'][] = 'ModeExtension varies between first frame and other frames (known free-format issue in LAME 3.88)';
1157                                 $info['audio']['codec']   = 'LAME';
1158                                 $info['audio']['encoder'] = 'LAME3.88';
1159                                 $SyncPattern1 = substr($SyncPattern1, 0, 3);
1160                                 $SyncPattern2 = substr($SyncPattern2, 0, 3);
1161                         }
1162                 }
1163
1164                 if ($deepscan) {
1165
1166                         $ActualFrameLengthValues = array();
1167                         $nextoffset = $offset + $framelength;
1168                         while ($nextoffset < ($info['avdataend'] - 6)) {
1169                                 fseek($this->getid3->fp, $nextoffset - 1, SEEK_SET);
1170                                 $NextSyncPattern = fread($this->getid3->fp, 6);
1171                                 if ((substr($NextSyncPattern, 1, strlen($SyncPattern1)) == $SyncPattern1) || (substr($NextSyncPattern, 1, strlen($SyncPattern2)) == $SyncPattern2)) {
1172                                         // good - found where expected
1173                                         $ActualFrameLengthValues[] = $framelength;
1174                                 } elseif ((substr($NextSyncPattern, 0, strlen($SyncPattern1)) == $SyncPattern1) || (substr($NextSyncPattern, 0, strlen($SyncPattern2)) == $SyncPattern2)) {
1175                                         // ok - found one byte earlier than expected (last frame wasn't padded, first frame was)
1176                                         $ActualFrameLengthValues[] = ($framelength - 1);
1177                                         $nextoffset--;
1178                                 } elseif ((substr($NextSyncPattern, 2, strlen($SyncPattern1)) == $SyncPattern1) || (substr($NextSyncPattern, 2, strlen($SyncPattern2)) == $SyncPattern2)) {
1179                                         // ok - found one byte later than expected (last frame was padded, first frame wasn't)
1180                                         $ActualFrameLengthValues[] = ($framelength + 1);
1181                                         $nextoffset++;
1182                                 } else {
1183                                         $info['error'][] = 'Did not find expected free-format sync pattern at offset '.$nextoffset;
1184                                         return false;
1185                                 }
1186                                 $nextoffset += $framelength;
1187                         }
1188                         if (count($ActualFrameLengthValues) > 0) {
1189                                 $framelength = intval(round(array_sum($ActualFrameLengthValues) / count($ActualFrameLengthValues)));
1190                         }
1191                 }
1192                 return $framelength;
1193         }
1194
1195         public function getOnlyMPEGaudioInfoBruteForce() {
1196                 $MPEGaudioHeaderDecodeCache   = array();
1197                 $MPEGaudioHeaderValidCache    = array();
1198                 $MPEGaudioHeaderLengthCache   = array();
1199                 $MPEGaudioVersionLookup       = self::MPEGaudioVersionArray();
1200                 $MPEGaudioLayerLookup         = self::MPEGaudioLayerArray();
1201                 $MPEGaudioBitrateLookup       = self::MPEGaudioBitrateArray();
1202                 $MPEGaudioFrequencyLookup     = self::MPEGaudioFrequencyArray();
1203                 $MPEGaudioChannelModeLookup   = self::MPEGaudioChannelModeArray();
1204                 $MPEGaudioModeExtensionLookup = self::MPEGaudioModeExtensionArray();
1205                 $MPEGaudioEmphasisLookup      = self::MPEGaudioEmphasisArray();
1206                 $LongMPEGversionLookup        = array();
1207                 $LongMPEGlayerLookup          = array();
1208                 $LongMPEGbitrateLookup        = array();
1209                 $LongMPEGpaddingLookup        = array();
1210                 $LongMPEGfrequencyLookup      = array();
1211                 $Distribution['bitrate']      = array();
1212                 $Distribution['frequency']    = array();
1213                 $Distribution['layer']        = array();
1214                 $Distribution['version']      = array();
1215                 $Distribution['padding']      = array();
1216
1217                 $info = &$this->getid3->info;
1218                 fseek($this->getid3->fp, $info['avdataoffset'], SEEK_SET);
1219
1220                 $max_frames_scan = 5000;
1221                 $frames_scanned  = 0;
1222
1223                 $previousvalidframe = $info['avdataoffset'];
1224                 while (ftell($this->getid3->fp) < $info['avdataend']) {
1225                         set_time_limit(30);
1226                         $head4 = fread($this->getid3->fp, 4);
1227                         if (strlen($head4) < 4) {
1228                                 break;
1229                         }
1230                         if ($head4{0} != "\xFF") {
1231                                 for ($i = 1; $i < 4; $i++) {
1232                                         if ($head4{$i} == "\xFF") {
1233                                                 fseek($this->getid3->fp, $i - 4, SEEK_CUR);
1234                                                 continue 2;
1235                                         }
1236                                 }
1237                                 continue;
1238                         }
1239                         if (!isset($MPEGaudioHeaderDecodeCache[$head4])) {
1240                                 $MPEGaudioHeaderDecodeCache[$head4] = self::MPEGaudioHeaderDecode($head4);
1241                         }
1242                         if (!isset($MPEGaudioHeaderValidCache[$head4])) {
1243                                 $MPEGaudioHeaderValidCache[$head4] = self::MPEGaudioHeaderValid($MPEGaudioHeaderDecodeCache[$head4], false, false);
1244                         }
1245                         if ($MPEGaudioHeaderValidCache[$head4]) {
1246
1247                                 if (!isset($MPEGaudioHeaderLengthCache[$head4])) {
1248                                         $LongMPEGversionLookup[$head4]   = $MPEGaudioVersionLookup[$MPEGaudioHeaderDecodeCache[$head4]['version']];
1249                                         $LongMPEGlayerLookup[$head4]     = $MPEGaudioLayerLookup[$MPEGaudioHeaderDecodeCache[$head4]['layer']];
1250                                         $LongMPEGbitrateLookup[$head4]   = $MPEGaudioBitrateLookup[$LongMPEGversionLookup[$head4]][$LongMPEGlayerLookup[$head4]][$MPEGaudioHeaderDecodeCache[$head4]['bitrate']];
1251                                         $LongMPEGpaddingLookup[$head4]   = (bool) $MPEGaudioHeaderDecodeCache[$head4]['padding'];
1252                                         $LongMPEGfrequencyLookup[$head4] = $MPEGaudioFrequencyLookup[$LongMPEGversionLookup[$head4]][$MPEGaudioHeaderDecodeCache[$head4]['sample_rate']];
1253                                         $MPEGaudioHeaderLengthCache[$head4] = self::MPEGaudioFrameLength(
1254                                                 $LongMPEGbitrateLookup[$head4],
1255                                                 $LongMPEGversionLookup[$head4],
1256                                                 $LongMPEGlayerLookup[$head4],
1257                                                 $LongMPEGpaddingLookup[$head4],
1258                                                 $LongMPEGfrequencyLookup[$head4]);
1259                                 }
1260                                 if ($MPEGaudioHeaderLengthCache[$head4] > 4) {
1261                                         $WhereWeWere = ftell($this->getid3->fp);
1262                                         fseek($this->getid3->fp, $MPEGaudioHeaderLengthCache[$head4] - 4, SEEK_CUR);
1263                                         $next4 = fread($this->getid3->fp, 4);
1264                                         if ($next4{0} == "\xFF") {
1265                                                 if (!isset($MPEGaudioHeaderDecodeCache[$next4])) {
1266                                                         $MPEGaudioHeaderDecodeCache[$next4] = self::MPEGaudioHeaderDecode($next4);
1267                                                 }
1268                                                 if (!isset($MPEGaudioHeaderValidCache[$next4])) {
1269                                                         $MPEGaudioHeaderValidCache[$next4] = self::MPEGaudioHeaderValid($MPEGaudioHeaderDecodeCache[$next4], false, false);
1270                                                 }
1271                                                 if ($MPEGaudioHeaderValidCache[$next4]) {
1272                                                         fseek($this->getid3->fp, -4, SEEK_CUR);
1273
1274                                                         getid3_lib::safe_inc($Distribution['bitrate'][$LongMPEGbitrateLookup[$head4]]);
1275                                                         getid3_lib::safe_inc($Distribution['layer'][$LongMPEGlayerLookup[$head4]]);
1276                                                         getid3_lib::safe_inc($Distribution['version'][$LongMPEGversionLookup[$head4]]);
1277                                                         getid3_lib::safe_inc($Distribution['padding'][intval($LongMPEGpaddingLookup[$head4])]);
1278                                                         getid3_lib::safe_inc($Distribution['frequency'][$LongMPEGfrequencyLookup[$head4]]);
1279                                                         if ($max_frames_scan && (++$frames_scanned >= $max_frames_scan)) {
1280                                                                 $pct_data_scanned = (ftell($this->getid3->fp) - $info['avdataoffset']) / ($info['avdataend'] - $info['avdataoffset']);
1281                                                                 $info['warning'][] = 'too many MPEG audio frames to scan, only scanned first '.$max_frames_scan.' frames ('.number_format($pct_data_scanned * 100, 1).'% of file) and extrapolated distribution, playtime and bitrate may be incorrect.';
1282                                                                 foreach ($Distribution as $key1 => $value1) {
1283                                                                         foreach ($value1 as $key2 => $value2) {
1284                                                                                 $Distribution[$key1][$key2] = round($value2 / $pct_data_scanned);
1285                                                                         }
1286                                                                 }
1287                                                                 break;
1288                                                         }
1289                                                         continue;
1290                                                 }
1291                                         }
1292                                         unset($next4);
1293                                         fseek($this->getid3->fp, $WhereWeWere - 3, SEEK_SET);
1294                                 }
1295
1296                         }
1297                 }
1298                 foreach ($Distribution as $key => $value) {
1299                         ksort($Distribution[$key], SORT_NUMERIC);
1300                 }
1301                 ksort($Distribution['version'], SORT_STRING);
1302                 $info['mpeg']['audio']['bitrate_distribution']   = $Distribution['bitrate'];
1303                 $info['mpeg']['audio']['frequency_distribution'] = $Distribution['frequency'];
1304                 $info['mpeg']['audio']['layer_distribution']     = $Distribution['layer'];
1305                 $info['mpeg']['audio']['version_distribution']   = $Distribution['version'];
1306                 $info['mpeg']['audio']['padding_distribution']   = $Distribution['padding'];
1307                 if (count($Distribution['version']) > 1) {
1308                         $info['error'][] = 'Corrupt file - more than one MPEG version detected';
1309                 }
1310                 if (count($Distribution['layer']) > 1) {
1311                         $info['error'][] = 'Corrupt file - more than one MPEG layer detected';
1312                 }
1313                 if (count($Distribution['frequency']) > 1) {
1314                         $info['error'][] = 'Corrupt file - more than one MPEG sample rate detected';
1315                 }
1316
1317
1318                 $bittotal = 0;
1319                 foreach ($Distribution['bitrate'] as $bitratevalue => $bitratecount) {
1320                         if ($bitratevalue != 'free') {
1321                                 $bittotal += ($bitratevalue * $bitratecount);
1322                         }
1323                 }
1324                 $info['mpeg']['audio']['frame_count']  = array_sum($Distribution['bitrate']);
1325                 if ($info['mpeg']['audio']['frame_count'] == 0) {
1326                         $info['error'][] = 'no MPEG audio frames found';
1327                         return false;
1328                 }
1329                 $info['mpeg']['audio']['bitrate']      = ($bittotal / $info['mpeg']['audio']['frame_count']);
1330                 $info['mpeg']['audio']['bitrate_mode'] = ((count($Distribution['bitrate']) > 0) ? 'vbr' : 'cbr');
1331                 $info['mpeg']['audio']['sample_rate']  = getid3_lib::array_max($Distribution['frequency'], true);
1332
1333                 $info['audio']['bitrate']      = $info['mpeg']['audio']['bitrate'];
1334                 $info['audio']['bitrate_mode'] = $info['mpeg']['audio']['bitrate_mode'];
1335                 $info['audio']['sample_rate']  = $info['mpeg']['audio']['sample_rate'];
1336                 $info['audio']['dataformat']   = 'mp'.getid3_lib::array_max($Distribution['layer'], true);
1337                 $info['fileformat']            = $info['audio']['dataformat'];
1338
1339                 return true;
1340         }
1341
1342
1343         public function getOnlyMPEGaudioInfo($avdataoffset, $BitrateHistogram=false) {
1344                 // looks for synch, decodes MPEG audio header
1345
1346                 $info = &$this->getid3->info;
1347
1348                 static $MPEGaudioVersionLookup;
1349                 static $MPEGaudioLayerLookup;
1350                 static $MPEGaudioBitrateLookup;
1351                 if (empty($MPEGaudioVersionLookup)) {
1352                    $MPEGaudioVersionLookup = self::MPEGaudioVersionArray();
1353                    $MPEGaudioLayerLookup   = self::MPEGaudioLayerArray();
1354                    $MPEGaudioBitrateLookup = self::MPEGaudioBitrateArray();
1355
1356                 }
1357
1358                 fseek($this->getid3->fp, $avdataoffset, SEEK_SET);
1359                 $sync_seek_buffer_size = min(128 * 1024, $info['avdataend'] - $avdataoffset);
1360                 if ($sync_seek_buffer_size <= 0) {
1361                         $info['error'][] = 'Invalid $sync_seek_buffer_size at offset '.$avdataoffset;
1362                         return false;
1363                 }
1364                 $header = fread($this->getid3->fp, $sync_seek_buffer_size);
1365                 $sync_seek_buffer_size = strlen($header);
1366                 $SynchSeekOffset = 0;
1367                 while ($SynchSeekOffset < $sync_seek_buffer_size) {
1368                         if ((($avdataoffset + $SynchSeekOffset)  < $info['avdataend']) && !feof($this->getid3->fp)) {
1369
1370                                 if ($SynchSeekOffset > $sync_seek_buffer_size) {
1371                                         // if a synch's not found within the first 128k bytes, then give up
1372                                         $info['error'][] = 'Could not find valid MPEG audio synch within the first '.round($sync_seek_buffer_size / 1024).'kB';
1373                                         if (isset($info['audio']['bitrate'])) {
1374                                                 unset($info['audio']['bitrate']);
1375                                         }
1376                                         if (isset($info['mpeg']['audio'])) {
1377                                                 unset($info['mpeg']['audio']);
1378                                         }
1379                                         if (empty($info['mpeg'])) {
1380                                                 unset($info['mpeg']);
1381                                         }
1382                                         return false;
1383
1384                                 } elseif (feof($this->getid3->fp)) {
1385
1386                                         $info['error'][] = 'Could not find valid MPEG audio synch before end of file';
1387                                         if (isset($info['audio']['bitrate'])) {
1388                                                 unset($info['audio']['bitrate']);
1389                                         }
1390                                         if (isset($info['mpeg']['audio'])) {
1391                                                 unset($info['mpeg']['audio']);
1392                                         }
1393                                         if (isset($info['mpeg']) && (!is_array($info['mpeg']) || (count($info['mpeg']) == 0))) {
1394                                                 unset($info['mpeg']);
1395                                         }
1396                                         return false;
1397                                 }
1398                         }
1399
1400                         if (($SynchSeekOffset + 1) >= strlen($header)) {
1401                                 $info['error'][] = 'Could not find valid MPEG synch before end of file';
1402                                 return false;
1403                         }
1404
1405                         if (($header{$SynchSeekOffset} == "\xFF") && ($header{($SynchSeekOffset + 1)} > "\xE0")) { // synch detected
1406                                 if (!isset($FirstFrameThisfileInfo) && !isset($info['mpeg']['audio'])) {
1407                                         $FirstFrameThisfileInfo = $info;
1408                                         $FirstFrameAVDataOffset = $avdataoffset + $SynchSeekOffset;
1409                                         if (!$this->decodeMPEGaudioHeader($FirstFrameAVDataOffset, $FirstFrameThisfileInfo, false)) {
1410                                                 // if this is the first valid MPEG-audio frame, save it in case it's a VBR header frame and there's
1411                                                 // garbage between this frame and a valid sequence of MPEG-audio frames, to be restored below
1412                                                 unset($FirstFrameThisfileInfo);
1413                                         }
1414                                 }
1415
1416                                 $dummy = $info; // only overwrite real data if valid header found
1417                                 if ($this->decodeMPEGaudioHeader($avdataoffset + $SynchSeekOffset, $dummy, true)) {
1418                                         $info = $dummy;
1419                                         $info['avdataoffset'] = $avdataoffset + $SynchSeekOffset;
1420                                         switch (isset($info['fileformat']) ? $info['fileformat'] : '') {
1421                                                 case '':
1422                                                 case 'id3':
1423                                                 case 'ape':
1424                                                 case 'mp3':
1425                                                         $info['fileformat']          = 'mp3';
1426                                                         $info['audio']['dataformat'] = 'mp3';
1427                                                         break;
1428                                         }
1429                                         if (isset($FirstFrameThisfileInfo['mpeg']['audio']['bitrate_mode']) && ($FirstFrameThisfileInfo['mpeg']['audio']['bitrate_mode'] == 'vbr')) {
1430                                                 if (!(abs($info['audio']['bitrate'] - $FirstFrameThisfileInfo['audio']['bitrate']) <= 1)) {
1431                                                         // If there is garbage data between a valid VBR header frame and a sequence
1432                                                         // of valid MPEG-audio frames the VBR data is no longer discarded.
1433                                                         $info = $FirstFrameThisfileInfo;
1434                                                         $info['avdataoffset']        = $FirstFrameAVDataOffset;
1435                                                         $info['fileformat']          = 'mp3';
1436                                                         $info['audio']['dataformat'] = 'mp3';
1437                                                         $dummy                       = $info;
1438                                                         unset($dummy['mpeg']['audio']);
1439                                                         $GarbageOffsetStart = $FirstFrameAVDataOffset + $FirstFrameThisfileInfo['mpeg']['audio']['framelength'];
1440                                                         $GarbageOffsetEnd   = $avdataoffset + $SynchSeekOffset;
1441                                                         if ($this->decodeMPEGaudioHeader($GarbageOffsetEnd, $dummy, true, true)) {
1442                                                                 $info = $dummy;
1443                                                                 $info['avdataoffset'] = $GarbageOffsetEnd;
1444                                                                 $info['warning'][] = 'apparently-valid VBR header not used because could not find '.GETID3_MP3_VALID_CHECK_FRAMES.' consecutive MPEG-audio frames immediately after VBR header (garbage data for '.($GarbageOffsetEnd - $GarbageOffsetStart).' bytes between '.$GarbageOffsetStart.' and '.$GarbageOffsetEnd.'), but did find valid CBR stream starting at '.$GarbageOffsetEnd;
1445                                                         } else {
1446                                                                 $info['warning'][] = 'using data from VBR header even though could not find '.GETID3_MP3_VALID_CHECK_FRAMES.' consecutive MPEG-audio frames immediately after VBR header (garbage data for '.($GarbageOffsetEnd - $GarbageOffsetStart).' bytes between '.$GarbageOffsetStart.' and '.$GarbageOffsetEnd.')';
1447                                                         }
1448                                                 }
1449                                         }
1450                                         if (isset($info['mpeg']['audio']['bitrate_mode']) && ($info['mpeg']['audio']['bitrate_mode'] == 'vbr') && !isset($info['mpeg']['audio']['VBR_method'])) {
1451                                                 // VBR file with no VBR header
1452                                                 $BitrateHistogram = true;
1453                                         }
1454
1455                                         if ($BitrateHistogram) {
1456
1457                                                 $info['mpeg']['audio']['stereo_distribution']  = array('stereo'=>0, 'joint stereo'=>0, 'dual channel'=>0, 'mono'=>0);
1458                                                 $info['mpeg']['audio']['version_distribution'] = array('1'=>0, '2'=>0, '2.5'=>0);
1459
1460                                                 if ($info['mpeg']['audio']['version'] == '1') {
1461                                                         if ($info['mpeg']['audio']['layer'] == 3) {
1462                                                                 $info['mpeg']['audio']['bitrate_distribution'] = array('free'=>0, 32000=>0, 40000=>0, 48000=>0, 56000=>0, 64000=>0, 80000=>0, 96000=>0, 112000=>0, 128000=>0, 160000=>0, 192000=>0, 224000=>0, 256000=>0, 320000=>0);
1463                                                         } elseif ($info['mpeg']['audio']['layer'] == 2) {
1464                                                                 $info['mpeg']['audio']['bitrate_distribution'] = array('free'=>0, 32000=>0, 48000=>0, 56000=>0, 64000=>0, 80000=>0, 96000=>0, 112000=>0, 128000=>0, 160000=>0, 192000=>0, 224000=>0, 256000=>0, 320000=>0, 384000=>0);
1465                                                         } elseif ($info['mpeg']['audio']['layer'] == 1) {
1466                                                                 $info['mpeg']['audio']['bitrate_distribution'] = array('free'=>0, 32000=>0, 64000=>0, 96000=>0, 128000=>0, 160000=>0, 192000=>0, 224000=>0, 256000=>0, 288000=>0, 320000=>0, 352000=>0, 384000=>0, 416000=>0, 448000=>0);
1467                                                         }
1468                                                 } elseif ($info['mpeg']['audio']['layer'] == 1) {
1469                                                         $info['mpeg']['audio']['bitrate_distribution'] = array('free'=>0, 32000=>0, 48000=>0, 56000=>0, 64000=>0, 80000=>0, 96000=>0, 112000=>0, 128000=>0, 144000=>0, 160000=>0, 176000=>0, 192000=>0, 224000=>0, 256000=>0);
1470                                                 } else {
1471                                                         $info['mpeg']['audio']['bitrate_distribution'] = array('free'=>0, 8000=>0, 16000=>0, 24000=>0, 32000=>0, 40000=>0, 48000=>0, 56000=>0, 64000=>0, 80000=>0, 96000=>0, 112000=>0, 128000=>0, 144000=>0, 160000=>0);
1472                                                 }
1473
1474                                                 $dummy = array('error'=>$info['error'], 'warning'=>$info['warning'], 'avdataend'=>$info['avdataend'], 'avdataoffset'=>$info['avdataoffset']);
1475                                                 $synchstartoffset = $info['avdataoffset'];
1476                                                 fseek($this->getid3->fp, $info['avdataoffset'], SEEK_SET);
1477
1478                                                 // you can play with these numbers:
1479                                                 $max_frames_scan  = 50000;
1480                                                 $max_scan_segments = 10;
1481
1482                                                 // don't play with these numbers:
1483                                                 $FastMode = false;
1484                                                 $SynchErrorsFound = 0;
1485                                                 $frames_scanned   = 0;
1486                                                 $this_scan_segment = 0;
1487                                                 $frames_scan_per_segment = ceil($max_frames_scan / $max_scan_segments);
1488                                                 $pct_data_scanned = 0;
1489                                                 for ($current_segment = 0; $current_segment < $max_scan_segments; $current_segment++) {
1490                                                         $frames_scanned_this_segment = 0;
1491                                                         if (ftell($this->getid3->fp) >= $info['avdataend']) {
1492                                                                 break;
1493                                                         }
1494                                                         $scan_start_offset[$current_segment] = max(ftell($this->getid3->fp), $info['avdataoffset'] + round($current_segment * (($info['avdataend'] - $info['avdataoffset']) / $max_scan_segments)));
1495                                                         if ($current_segment > 0) {
1496                                                                 fseek($this->getid3->fp, $scan_start_offset[$current_segment], SEEK_SET);
1497                                                                 $buffer_4k = fread($this->getid3->fp, 4096);
1498                                                                 for ($j = 0; $j < (strlen($buffer_4k) - 4); $j++) {
1499                                                                         if (($buffer_4k{$j} == "\xFF") && ($buffer_4k{($j + 1)} > "\xE0")) { // synch detected
1500                                                                                 if ($this->decodeMPEGaudioHeader($scan_start_offset[$current_segment] + $j, $dummy, false, false, $FastMode)) {
1501                                                                                         $calculated_next_offset = $scan_start_offset[$current_segment] + $j + $dummy['mpeg']['audio']['framelength'];
1502                                                                                         if ($this->decodeMPEGaudioHeader($calculated_next_offset, $dummy, false, false, $FastMode)) {
1503                                                                                                 $scan_start_offset[$current_segment] += $j;
1504                                                                                                 break;
1505                                                                                         }
1506                                                                                 }
1507                                                                         }
1508                                                                 }
1509                                                         }
1510                                                         $synchstartoffset = $scan_start_offset[$current_segment];
1511                                                         while ($this->decodeMPEGaudioHeader($synchstartoffset, $dummy, false, false, $FastMode)) {
1512                                                                 $FastMode = true;
1513                                                                 $thisframebitrate = $MPEGaudioBitrateLookup[$MPEGaudioVersionLookup[$dummy['mpeg']['audio']['raw']['version']]][$MPEGaudioLayerLookup[$dummy['mpeg']['audio']['raw']['layer']]][$dummy['mpeg']['audio']['raw']['bitrate']];
1514
1515                                                                 if (empty($dummy['mpeg']['audio']['framelength'])) {
1516                                                                         $SynchErrorsFound++;
1517                                                                         $synchstartoffset++;
1518                                                                 } else {
1519                                                                         getid3_lib::safe_inc($info['mpeg']['audio']['bitrate_distribution'][$thisframebitrate]);
1520                                                                         getid3_lib::safe_inc($info['mpeg']['audio']['stereo_distribution'][$dummy['mpeg']['audio']['channelmode']]);
1521                                                                         getid3_lib::safe_inc($info['mpeg']['audio']['version_distribution'][$dummy['mpeg']['audio']['version']]);
1522                                                                         $synchstartoffset += $dummy['mpeg']['audio']['framelength'];
1523                                                                 }
1524                                                                 $frames_scanned++;
1525                                                                 if ($frames_scan_per_segment && (++$frames_scanned_this_segment >= $frames_scan_per_segment)) {
1526                                                                         $this_pct_scanned = (ftell($this->getid3->fp) - $scan_start_offset[$current_segment]) / ($info['avdataend'] - $info['avdataoffset']);
1527                                                                         if (($current_segment == 0) && (($this_pct_scanned * $max_scan_segments) >= 1)) {
1528                                                                                 // file likely contains < $max_frames_scan, just scan as one segment
1529                                                                                 $max_scan_segments = 1;
1530                                                                                 $frames_scan_per_segment = $max_frames_scan;
1531                                                                         } else {
1532                                                                                 $pct_data_scanned += $this_pct_scanned;
1533                                                                                 break;
1534                                                                         }
1535                                                                 }
1536                                                         }
1537                                                 }
1538                                                 if ($pct_data_scanned > 0) {
1539                                                         $info['warning'][] = 'too many MPEG audio frames to scan, only scanned '.$frames_scanned.' frames in '.$max_scan_segments.' segments ('.number_format($pct_data_scanned * 100, 1).'% of file) and extrapolated distribution, playtime and bitrate may be incorrect.';
1540                                                         foreach ($info['mpeg']['audio'] as $key1 => $value1) {
1541                                                                 if (!preg_match('#_distribution$#i', $key1)) {
1542                                                                         continue;
1543                                                                 }
1544                                                                 foreach ($value1 as $key2 => $value2) {
1545                                                                         $info['mpeg']['audio'][$key1][$key2] = round($value2 / $pct_data_scanned);
1546                                                                 }
1547                                                         }
1548                                                 }
1549
1550                                                 if ($SynchErrorsFound > 0) {
1551                                                         $info['warning'][] = 'Found '.$SynchErrorsFound.' synch errors in histogram analysis';
1552                                                         //return false;
1553                                                 }
1554
1555                                                 $bittotal     = 0;
1556                                                 $framecounter = 0;
1557                                                 foreach ($info['mpeg']['audio']['bitrate_distribution'] as $bitratevalue => $bitratecount) {
1558                                                         $framecounter += $bitratecount;
1559                                                         if ($bitratevalue != 'free') {
1560                                                                 $bittotal += ($bitratevalue * $bitratecount);
1561                                                         }
1562                                                 }
1563                                                 if ($framecounter == 0) {
1564                                                         $info['error'][] = 'Corrupt MP3 file: framecounter == zero';
1565                                                         return false;
1566                                                 }
1567                                                 $info['mpeg']['audio']['frame_count'] = getid3_lib::CastAsInt($framecounter);
1568                                                 $info['mpeg']['audio']['bitrate']     = ($bittotal / $framecounter);
1569
1570                                                 $info['audio']['bitrate'] = $info['mpeg']['audio']['bitrate'];
1571
1572
1573                                                 // Definitively set VBR vs CBR, even if the Xing/LAME/VBRI header says differently
1574                                                 $distinct_bitrates = 0;
1575                                                 foreach ($info['mpeg']['audio']['bitrate_distribution'] as $bitrate_value => $bitrate_count) {
1576                                                         if ($bitrate_count > 0) {
1577                                                                 $distinct_bitrates++;
1578                                                         }
1579                                                 }
1580                                                 if ($distinct_bitrates > 1) {
1581                                                         $info['mpeg']['audio']['bitrate_mode'] = 'vbr';
1582                                                 } else {
1583                                                         $info['mpeg']['audio']['bitrate_mode'] = 'cbr';
1584                                                 }
1585                                                 $info['audio']['bitrate_mode'] = $info['mpeg']['audio']['bitrate_mode'];
1586
1587                                         }
1588
1589                                         break; // exit while()
1590                                 }
1591                         }
1592
1593                         $SynchSeekOffset++;
1594                         if (($avdataoffset + $SynchSeekOffset) >= $info['avdataend']) {
1595                                 // end of file/data
1596
1597                                 if (empty($info['mpeg']['audio'])) {
1598
1599                                         $info['error'][] = 'could not find valid MPEG synch before end of file';
1600                                         if (isset($info['audio']['bitrate'])) {
1601                                                 unset($info['audio']['bitrate']);
1602                                         }
1603                                         if (isset($info['mpeg']['audio'])) {
1604                                                 unset($info['mpeg']['audio']);
1605                                         }
1606                                         if (isset($info['mpeg']) && (!is_array($info['mpeg']) || empty($info['mpeg']))) {
1607                                                 unset($info['mpeg']);
1608                                         }
1609                                         return false;
1610
1611                                 }
1612                                 break;
1613                         }
1614
1615                 }
1616                 $info['audio']['channels']        = $info['mpeg']['audio']['channels'];
1617                 $info['audio']['channelmode']     = $info['mpeg']['audio']['channelmode'];
1618                 $info['audio']['sample_rate']     = $info['mpeg']['audio']['sample_rate'];
1619                 return true;
1620         }
1621
1622
1623         public static function MPEGaudioVersionArray() {
1624                 static $MPEGaudioVersion = array('2.5', false, '2', '1');
1625                 return $MPEGaudioVersion;
1626         }
1627
1628         public static function MPEGaudioLayerArray() {
1629                 static $MPEGaudioLayer = array(false, 3, 2, 1);
1630                 return $MPEGaudioLayer;
1631         }
1632
1633         public static function MPEGaudioBitrateArray() {
1634                 static $MPEGaudioBitrate;
1635                 if (empty($MPEGaudioBitrate)) {
1636                         $MPEGaudioBitrate = array (
1637                                 '1'  =>  array (1 => array('free', 32000, 64000, 96000, 128000, 160000, 192000, 224000, 256000, 288000, 320000, 352000, 384000, 416000, 448000),
1638                                                                 2 => array('free', 32000, 48000, 56000,  64000,  80000,  96000, 112000, 128000, 160000, 192000, 224000, 256000, 320000, 384000),
1639                                                                 3 => array('free', 32000, 40000, 48000,  56000,  64000,  80000,  96000, 112000, 128000, 160000, 192000, 224000, 256000, 320000)
1640                                                            ),
1641
1642                                 '2'  =>  array (1 => array('free', 32000, 48000, 56000,  64000,  80000,  96000, 112000, 128000, 144000, 160000, 176000, 192000, 224000, 256000),
1643                                                                 2 => array('free',  8000, 16000, 24000,  32000,  40000,  48000,  56000,  64000,  80000,  96000, 112000, 128000, 144000, 160000),
1644                                                            )
1645                         );
1646                         $MPEGaudioBitrate['2'][3] = $MPEGaudioBitrate['2'][2];
1647                         $MPEGaudioBitrate['2.5']  = $MPEGaudioBitrate['2'];
1648                 }
1649                 return $MPEGaudioBitrate;
1650         }
1651
1652         public static function MPEGaudioFrequencyArray() {
1653                 static $MPEGaudioFrequency;
1654                 if (empty($MPEGaudioFrequency)) {
1655                         $MPEGaudioFrequency = array (
1656                                 '1'   => array(44100, 48000, 32000),
1657                                 '2'   => array(22050, 24000, 16000),
1658                                 '2.5' => array(11025, 12000,  8000)
1659                         );
1660                 }
1661                 return $MPEGaudioFrequency;
1662         }
1663
1664         public static function MPEGaudioChannelModeArray() {
1665                 static $MPEGaudioChannelMode = array('stereo', 'joint stereo', 'dual channel', 'mono');
1666                 return $MPEGaudioChannelMode;
1667         }
1668
1669         public static function MPEGaudioModeExtensionArray() {
1670                 static $MPEGaudioModeExtension;
1671                 if (empty($MPEGaudioModeExtension)) {
1672                         $MPEGaudioModeExtension = array (
1673                                 1 => array('4-31', '8-31', '12-31', '16-31'),
1674                                 2 => array('4-31', '8-31', '12-31', '16-31'),
1675                                 3 => array('', 'IS', 'MS', 'IS+MS')
1676                         );
1677                 }
1678                 return $MPEGaudioModeExtension;
1679         }
1680
1681         public static function MPEGaudioEmphasisArray() {
1682                 static $MPEGaudioEmphasis = array('none', '50/15ms', false, 'CCIT J.17');
1683                 return $MPEGaudioEmphasis;
1684         }
1685
1686         public static function MPEGaudioHeaderBytesValid($head4, $allowBitrate15=false) {
1687                 return self::MPEGaudioHeaderValid(self::MPEGaudioHeaderDecode($head4), false, $allowBitrate15);
1688         }
1689
1690         public static function MPEGaudioHeaderValid($rawarray, $echoerrors=false, $allowBitrate15=false) {
1691                 if (($rawarray['synch'] & 0x0FFE) != 0x0FFE) {
1692                         return false;
1693                 }
1694
1695                 static $MPEGaudioVersionLookup;
1696                 static $MPEGaudioLayerLookup;
1697                 static $MPEGaudioBitrateLookup;
1698                 static $MPEGaudioFrequencyLookup;
1699                 static $MPEGaudioChannelModeLookup;
1700                 static $MPEGaudioModeExtensionLookup;
1701                 static $MPEGaudioEmphasisLookup;
1702                 if (empty($MPEGaudioVersionLookup)) {
1703                         $MPEGaudioVersionLookup       = self::MPEGaudioVersionArray();
1704                         $MPEGaudioLayerLookup         = self::MPEGaudioLayerArray();
1705                         $MPEGaudioBitrateLookup       = self::MPEGaudioBitrateArray();
1706                         $MPEGaudioFrequencyLookup     = self::MPEGaudioFrequencyArray();
1707                         $MPEGaudioChannelModeLookup   = self::MPEGaudioChannelModeArray();
1708                         $MPEGaudioModeExtensionLookup = self::MPEGaudioModeExtensionArray();
1709                         $MPEGaudioEmphasisLookup      = self::MPEGaudioEmphasisArray();
1710                 }
1711
1712                 if (isset($MPEGaudioVersionLookup[$rawarray['version']])) {
1713                         $decodedVersion = $MPEGaudioVersionLookup[$rawarray['version']];
1714                 } else {
1715                         echo ($echoerrors ? "\n".'invalid Version ('.$rawarray['version'].')' : '');
1716                         return false;
1717                 }
1718                 if (isset($MPEGaudioLayerLookup[$rawarray['layer']])) {
1719                         $decodedLayer = $MPEGaudioLayerLookup[$rawarray['layer']];
1720                 } else {
1721                         echo ($echoerrors ? "\n".'invalid Layer ('.$rawarray['layer'].')' : '');
1722                         return false;
1723                 }
1724                 if (!isset($MPEGaudioBitrateLookup[$decodedVersion][$decodedLayer][$rawarray['bitrate']])) {
1725                         echo ($echoerrors ? "\n".'invalid Bitrate ('.$rawarray['bitrate'].')' : '');
1726                         if ($rawarray['bitrate'] == 15) {
1727                                 // known issue in LAME 3.90 - 3.93.1 where free-format has bitrate ID of 15 instead of 0
1728                                 // let it go through here otherwise file will not be identified
1729                                 if (!$allowBitrate15) {
1730                                         return false;
1731                                 }
1732                         } else {
1733                                 return false;
1734                         }
1735                 }
1736                 if (!isset($MPEGaudioFrequencyLookup[$decodedVersion][$rawarray['sample_rate']])) {
1737                         echo ($echoerrors ? "\n".'invalid Frequency ('.$rawarray['sample_rate'].')' : '');
1738                         return false;
1739                 }
1740                 if (!isset($MPEGaudioChannelModeLookup[$rawarray['channelmode']])) {
1741                         echo ($echoerrors ? "\n".'invalid ChannelMode ('.$rawarray['channelmode'].')' : '');
1742                         return false;
1743                 }
1744                 if (!isset($MPEGaudioModeExtensionLookup[$decodedLayer][$rawarray['modeextension']])) {
1745                         echo ($echoerrors ? "\n".'invalid Mode Extension ('.$rawarray['modeextension'].')' : '');
1746                         return false;
1747                 }
1748                 if (!isset($MPEGaudioEmphasisLookup[$rawarray['emphasis']])) {
1749                         echo ($echoerrors ? "\n".'invalid Emphasis ('.$rawarray['emphasis'].')' : '');
1750                         return false;
1751                 }
1752                 // These are just either set or not set, you can't mess that up :)
1753                 // $rawarray['protection'];
1754                 // $rawarray['padding'];
1755                 // $rawarray['private'];
1756                 // $rawarray['copyright'];
1757                 // $rawarray['original'];
1758
1759                 return true;
1760         }
1761
1762         public static function MPEGaudioHeaderDecode($Header4Bytes) {
1763                 // AAAA AAAA  AAAB BCCD  EEEE FFGH  IIJJ KLMM
1764                 // A - Frame sync (all bits set)
1765                 // B - MPEG Audio version ID
1766                 // C - Layer description
1767                 // D - Protection bit
1768                 // E - Bitrate index
1769                 // F - Sampling rate frequency index
1770                 // G - Padding bit
1771                 // H - Private bit
1772                 // I - Channel Mode
1773                 // J - Mode extension (Only if Joint stereo)
1774                 // K - Copyright
1775                 // L - Original
1776                 // M - Emphasis
1777
1778                 if (strlen($Header4Bytes) != 4) {
1779                         return false;
1780                 }
1781
1782                 $MPEGrawHeader['synch']         = (getid3_lib::BigEndian2Int(substr($Header4Bytes, 0, 2)) & 0xFFE0) >> 4;
1783                 $MPEGrawHeader['version']       = (ord($Header4Bytes{1}) & 0x18) >> 3; //    BB
1784                 $MPEGrawHeader['layer']         = (ord($Header4Bytes{1}) & 0x06) >> 1; //      CC
1785                 $MPEGrawHeader['protection']    = (ord($Header4Bytes{1}) & 0x01);      //        D
1786                 $MPEGrawHeader['bitrate']       = (ord($Header4Bytes{2}) & 0xF0) >> 4; // EEEE
1787                 $MPEGrawHeader['sample_rate']   = (ord($Header4Bytes{2}) & 0x0C) >> 2; //     FF
1788                 $MPEGrawHeader['padding']       = (ord($Header4Bytes{2}) & 0x02) >> 1; //       G
1789                 $MPEGrawHeader['private']       = (ord($Header4Bytes{2}) & 0x01);      //        H
1790                 $MPEGrawHeader['channelmode']   = (ord($Header4Bytes{3}) & 0xC0) >> 6; // II
1791                 $MPEGrawHeader['modeextension'] = (ord($Header4Bytes{3}) & 0x30) >> 4; //   JJ
1792                 $MPEGrawHeader['copyright']     = (ord($Header4Bytes{3}) & 0x08) >> 3; //     K
1793                 $MPEGrawHeader['original']      = (ord($Header4Bytes{3}) & 0x04) >> 2; //      L
1794                 $MPEGrawHeader['emphasis']      = (ord($Header4Bytes{3}) & 0x03);      //       MM
1795
1796                 return $MPEGrawHeader;
1797         }
1798
1799         public static function MPEGaudioFrameLength(&$bitrate, &$version, &$layer, $padding, &$samplerate) {
1800                 static $AudioFrameLengthCache = array();
1801
1802                 if (!isset($AudioFrameLengthCache[$bitrate][$version][$layer][$padding][$samplerate])) {
1803                         $AudioFrameLengthCache[$bitrate][$version][$layer][$padding][$samplerate] = false;
1804                         if ($bitrate != 'free') {
1805
1806                                 if ($version == '1') {
1807
1808                                         if ($layer == '1') {
1809
1810                                                 // For Layer I slot is 32 bits long
1811                                                 $FrameLengthCoefficient = 48;
1812                                                 $SlotLength = 4;
1813
1814                                         } else { // Layer 2 / 3
1815
1816                                                 // for Layer 2 and Layer 3 slot is 8 bits long.
1817                                                 $FrameLengthCoefficient = 144;
1818                                                 $SlotLength = 1;
1819
1820                                         }
1821
1822                                 } else { // MPEG-2 / MPEG-2.5
1823
1824                                         if ($layer == '1') {
1825
1826                                                 // For Layer I slot is 32 bits long
1827                                                 $FrameLengthCoefficient = 24;
1828                                                 $SlotLength = 4;
1829
1830                                         } elseif ($layer == '2') {
1831
1832                                                 // for Layer 2 and Layer 3 slot is 8 bits long.
1833                                                 $FrameLengthCoefficient = 144;
1834                                                 $SlotLength = 1;
1835
1836                                         } else { // layer 3
1837
1838                                                 // for Layer 2 and Layer 3 slot is 8 bits long.
1839                                                 $FrameLengthCoefficient = 72;
1840                                                 $SlotLength = 1;
1841
1842                                         }
1843
1844                                 }
1845
1846                                 // FrameLengthInBytes = ((Coefficient * BitRate) / SampleRate) + Padding
1847                                 if ($samplerate > 0) {
1848                                         $NewFramelength  = ($FrameLengthCoefficient * $bitrate) / $samplerate;
1849                                         $NewFramelength  = floor($NewFramelength / $SlotLength) * $SlotLength; // round to next-lower multiple of SlotLength (1 byte for Layer 2/3, 4 bytes for Layer I)
1850                                         if ($padding) {
1851                                                 $NewFramelength += $SlotLength;
1852                                         }
1853                                         $AudioFrameLengthCache[$bitrate][$version][$layer][$padding][$samplerate] = (int) $NewFramelength;
1854                                 }
1855                         }
1856                 }
1857                 return $AudioFrameLengthCache[$bitrate][$version][$layer][$padding][$samplerate];
1858         }
1859
1860         public static function ClosestStandardMP3Bitrate($bit_rate) {
1861                 static $standard_bit_rates = array (320000, 256000, 224000, 192000, 160000, 128000, 112000, 96000, 80000, 64000, 56000, 48000, 40000, 32000, 24000, 16000, 8000);
1862                 static $bit_rate_table = array (0=>'-');
1863                 $round_bit_rate = intval(round($bit_rate, -3));
1864                 if (!isset($bit_rate_table[$round_bit_rate])) {
1865                         if ($round_bit_rate > max($standard_bit_rates)) {
1866                                 $bit_rate_table[$round_bit_rate] = round($bit_rate, 2 - strlen($bit_rate));
1867                         } else {
1868                                 $bit_rate_table[$round_bit_rate] = max($standard_bit_rates);
1869                                 foreach ($standard_bit_rates as $standard_bit_rate) {
1870                                         if ($round_bit_rate >= $standard_bit_rate + (($bit_rate_table[$round_bit_rate] - $standard_bit_rate) / 2)) {
1871                                                 break;
1872                                         }
1873                                         $bit_rate_table[$round_bit_rate] = $standard_bit_rate;
1874                                 }
1875                         }
1876                 }
1877                 return $bit_rate_table[$round_bit_rate];
1878         }
1879
1880         public static function XingVBRidOffset($version, $channelmode) {
1881                 static $XingVBRidOffsetCache = array();
1882                 if (empty($XingVBRidOffset)) {
1883                         $XingVBRidOffset = array (
1884                                 '1'   => array ('mono'          => 0x15, // 4 + 17 = 21
1885                                                                 'stereo'        => 0x24, // 4 + 32 = 36
1886                                                                 'joint stereo'  => 0x24,
1887                                                                 'dual channel'  => 0x24
1888                                                            ),
1889
1890                                 '2'   => array ('mono'          => 0x0D, // 4 +  9 = 13
1891                                                                 'stereo'        => 0x15, // 4 + 17 = 21
1892                                                                 'joint stereo'  => 0x15,
1893                                                                 'dual channel'  => 0x15
1894                                                            ),
1895
1896                                 '2.5' => array ('mono'          => 0x15,
1897                                                                 'stereo'        => 0x15,
1898                                                                 'joint stereo'  => 0x15,
1899                                                                 'dual channel'  => 0x15
1900                                                            )
1901                         );
1902                 }
1903                 return $XingVBRidOffset[$version][$channelmode];
1904         }
1905
1906         public static function LAMEvbrMethodLookup($VBRmethodID) {
1907                 static $LAMEvbrMethodLookup = array(
1908                         0x00 => 'unknown',
1909                         0x01 => 'cbr',
1910                         0x02 => 'abr',
1911                         0x03 => 'vbr-old / vbr-rh',
1912                         0x04 => 'vbr-new / vbr-mtrh',
1913                         0x05 => 'vbr-mt',
1914                         0x06 => 'vbr (full vbr method 4)',
1915                         0x08 => 'cbr (constant bitrate 2 pass)',
1916                         0x09 => 'abr (2 pass)',
1917                         0x0F => 'reserved'
1918                 );
1919                 return (isset($LAMEvbrMethodLookup[$VBRmethodID]) ? $LAMEvbrMethodLookup[$VBRmethodID] : '');
1920         }
1921
1922         public static function LAMEmiscStereoModeLookup($StereoModeID) {
1923                 static $LAMEmiscStereoModeLookup = array(
1924                         0 => 'mono',
1925                         1 => 'stereo',
1926                         2 => 'dual mono',
1927                         3 => 'joint stereo',
1928                         4 => 'forced stereo',
1929                         5 => 'auto',
1930                         6 => 'intensity stereo',
1931                         7 => 'other'
1932                 );
1933                 return (isset($LAMEmiscStereoModeLookup[$StereoModeID]) ? $LAMEmiscStereoModeLookup[$StereoModeID] : '');
1934         }
1935
1936         public static function LAMEmiscSourceSampleFrequencyLookup($SourceSampleFrequencyID) {
1937                 static $LAMEmiscSourceSampleFrequencyLookup = array(
1938                         0 => '<= 32 kHz',
1939                         1 => '44.1 kHz',
1940                         2 => '48 kHz',
1941                         3 => '> 48kHz'
1942                 );
1943                 return (isset($LAMEmiscSourceSampleFrequencyLookup[$SourceSampleFrequencyID]) ? $LAMEmiscSourceSampleFrequencyLookup[$SourceSampleFrequencyID] : '');
1944         }
1945
1946         public static function LAMEsurroundInfoLookup($SurroundInfoID) {
1947                 static $LAMEsurroundInfoLookup = array(
1948                         0 => 'no surround info',
1949                         1 => 'DPL encoding',
1950                         2 => 'DPL2 encoding',
1951                         3 => 'Ambisonic encoding'
1952                 );
1953                 return (isset($LAMEsurroundInfoLookup[$SurroundInfoID]) ? $LAMEsurroundInfoLookup[$SurroundInfoID] : 'reserved');
1954         }
1955
1956         public static function LAMEpresetUsedLookup($LAMEtag) {
1957
1958                 if ($LAMEtag['preset_used_id'] == 0) {
1959                         // no preset used (LAME >=3.93)
1960                         // no preset recorded (LAME <3.93)
1961                         return '';
1962                 }
1963                 $LAMEpresetUsedLookup = array();
1964
1965                 /////  THIS PART CANNOT BE STATIC .
1966                 for ($i = 8; $i <= 320; $i++) {
1967                         switch ($LAMEtag['vbr_method']) {
1968                                 case 'cbr':
1969                                         $LAMEpresetUsedLookup[$i] = '--alt-preset '.$LAMEtag['vbr_method'].' '.$i;
1970                                         break;
1971                                 case 'abr':
1972                                 default: // other VBR modes shouldn't be here(?)
1973                                         $LAMEpresetUsedLookup[$i] = '--alt-preset '.$i;
1974                                         break;
1975                         }
1976                 }
1977
1978                 // named old-style presets (studio, phone, voice, etc) are handled in GuessEncoderOptions()
1979
1980                 // named alt-presets
1981                 $LAMEpresetUsedLookup[1000] = '--r3mix';
1982                 $LAMEpresetUsedLookup[1001] = '--alt-preset standard';
1983                 $LAMEpresetUsedLookup[1002] = '--alt-preset extreme';
1984                 $LAMEpresetUsedLookup[1003] = '--alt-preset insane';
1985                 $LAMEpresetUsedLookup[1004] = '--alt-preset fast standard';
1986                 $LAMEpresetUsedLookup[1005] = '--alt-preset fast extreme';
1987                 $LAMEpresetUsedLookup[1006] = '--alt-preset medium';
1988                 $LAMEpresetUsedLookup[1007] = '--alt-preset fast medium';
1989
1990                 // LAME 3.94 additions/changes
1991                 $LAMEpresetUsedLookup[1010] = '--preset portable';                                                           // 3.94a15 Oct 21 2003
1992                 $LAMEpresetUsedLookup[1015] = '--preset radio';                                                              // 3.94a15 Oct 21 2003
1993
1994                 $LAMEpresetUsedLookup[320]  = '--preset insane';                                                             // 3.94a15 Nov 12 2003
1995                 $LAMEpresetUsedLookup[410]  = '-V9';
1996                 $LAMEpresetUsedLookup[420]  = '-V8';
1997                 $LAMEpresetUsedLookup[440]  = '-V6';
1998                 $LAMEpresetUsedLookup[430]  = '--preset radio';                                                              // 3.94a15 Nov 12 2003
1999                 $LAMEpresetUsedLookup[450]  = '--preset '.(($LAMEtag['raw']['vbr_method'] == 4) ? 'fast ' : '').'portable';  // 3.94a15 Nov 12 2003
2000                 $LAMEpresetUsedLookup[460]  = '--preset '.(($LAMEtag['raw']['vbr_method'] == 4) ? 'fast ' : '').'medium';    // 3.94a15 Nov 12 2003
2001                 $LAMEpresetUsedLookup[470]  = '--r3mix';                                                                     // 3.94b1  Dec 18 2003
2002                 $LAMEpresetUsedLookup[480]  = '--preset '.(($LAMEtag['raw']['vbr_method'] == 4) ? 'fast ' : '').'standard';  // 3.94a15 Nov 12 2003
2003                 $LAMEpresetUsedLookup[490]  = '-V1';
2004                 $LAMEpresetUsedLookup[500]  = '--preset '.(($LAMEtag['raw']['vbr_method'] == 4) ? 'fast ' : '').'extreme';   // 3.94a15 Nov 12 2003
2005
2006                 return (isset($LAMEpresetUsedLookup[$LAMEtag['preset_used_id']]) ? $LAMEpresetUsedLookup[$LAMEtag['preset_used_id']] : 'new/unknown preset: '.$LAMEtag['preset_used_id'].' - report to info@getid3.org');
2007         }
2008
2009 }