--- /dev/null
+<?php
+/////////////////////////////////////////////////////////////////
+/// getID3() by James Heinrich <info@getid3.org> //
+// available at http://getid3.sourceforge.net //
+// or http://www.getid3.org //
+// also https://github.com/JamesHeinrich/getID3 //
+/////////////////////////////////////////////////////////////////
+// See readme.txt for more details //
+/////////////////////////////////////////////////////////////////
+// //
+// module.audio.mpc.php //
+// module for analyzing Musepack/MPEG+ Audio files //
+// dependencies: NONE //
+// ///
+/////////////////////////////////////////////////////////////////
+
+
+class getid3_mpc extends getid3_handler
+{
+
+ public function Analyze() {
+ $info = &$this->getid3->info;
+
+ $info['mpc']['header'] = array();
+ $thisfile_mpc_header = &$info['mpc']['header'];
+
+ $info['fileformat'] = 'mpc';
+ $info['audio']['dataformat'] = 'mpc';
+ $info['audio']['bitrate_mode'] = 'vbr';
+ $info['audio']['channels'] = 2; // up to SV7 the format appears to have been hardcoded for stereo only
+ $info['audio']['lossless'] = false;
+
+ $this->fseek($info['avdataoffset']);
+ $MPCheaderData = $this->fread(4);
+ $info['mpc']['header']['preamble'] = substr($MPCheaderData, 0, 4); // should be 'MPCK' (SV8) or 'MP+' (SV7), otherwise possible stream data (SV4-SV6)
+ if (preg_match('#^MPCK#', $info['mpc']['header']['preamble'])) {
+
+ // this is SV8
+ return $this->ParseMPCsv8();
+
+ } elseif (preg_match('#^MP\+#', $info['mpc']['header']['preamble'])) {
+
+ // this is SV7
+ return $this->ParseMPCsv7();
+
+ } elseif (preg_match('/^[\x00\x01\x10\x11\x40\x41\x50\x51\x80\x81\x90\x91\xC0\xC1\xD0\xD1][\x20-37][\x00\x20\x40\x60\x80\xA0\xC0\xE0]/s', $MPCheaderData)) {
+
+ // this is SV4 - SV6, handle seperately
+ return $this->ParseMPCsv6();
+
+ } else {
+
+ $this->error('Expecting "MP+" or "MPCK" at offset '.$info['avdataoffset'].', found "'.getid3_lib::PrintHexBytes(substr($MPCheaderData, 0, 4)).'"');
+ unset($info['fileformat']);
+ unset($info['mpc']);
+ return false;
+
+ }
+ return false;
+ }
+
+
+ public function ParseMPCsv8() {
+ // this is SV8
+ // http://trac.musepack.net/trac/wiki/SV8Specification
+
+ $info = &$this->getid3->info;
+ $thisfile_mpc_header = &$info['mpc']['header'];
+
+ $keyNameSize = 2;
+ $maxHandledPacketLength = 9; // specs say: "n*8; 0 < n < 10"
+
+ $offset = $this->ftell();
+ while ($offset < $info['avdataend']) {
+ $thisPacket = array();
+ $thisPacket['offset'] = $offset;
+ $packet_offset = 0;
+
+ // Size is a variable-size field, could be 1-4 bytes (possibly more?)
+ // read enough data in and figure out the exact size later
+ $MPCheaderData = $this->fread($keyNameSize + $maxHandledPacketLength);
+ $packet_offset += $keyNameSize;
+ $thisPacket['key'] = substr($MPCheaderData, 0, $keyNameSize);
+ $thisPacket['key_name'] = $this->MPCsv8PacketName($thisPacket['key']);
+ if ($thisPacket['key'] == $thisPacket['key_name']) {
+ $this->error('Found unexpected key value "'.$thisPacket['key'].'" at offset '.$thisPacket['offset']);
+ return false;
+ }
+ $packetLength = 0;
+ $thisPacket['packet_size'] = $this->SV8variableLengthInteger(substr($MPCheaderData, $keyNameSize), $packetLength); // includes keyname and packet_size field
+ if ($thisPacket['packet_size'] === false) {
+ $this->error('Did not find expected packet length within '.$maxHandledPacketLength.' bytes at offset '.($thisPacket['offset'] + $keyNameSize));
+ return false;
+ }
+ $packet_offset += $packetLength;
+ $offset += $thisPacket['packet_size'];
+
+ switch ($thisPacket['key']) {
+ case 'SH': // Stream Header
+ $moreBytesToRead = $thisPacket['packet_size'] - $keyNameSize - $maxHandledPacketLength;
+ if ($moreBytesToRead > 0) {
+ $MPCheaderData .= $this->fread($moreBytesToRead);
+ }
+ $thisPacket['crc'] = getid3_lib::BigEndian2Int(substr($MPCheaderData, $packet_offset, 4));
+ $packet_offset += 4;
+ $thisPacket['stream_version'] = getid3_lib::BigEndian2Int(substr($MPCheaderData, $packet_offset, 1));
+ $packet_offset += 1;
+
+ $packetLength = 0;
+ $thisPacket['sample_count'] = $this->SV8variableLengthInteger(substr($MPCheaderData, $packet_offset, $maxHandledPacketLength), $packetLength);
+ $packet_offset += $packetLength;
+
+ $packetLength = 0;
+ $thisPacket['beginning_silence'] = $this->SV8variableLengthInteger(substr($MPCheaderData, $packet_offset, $maxHandledPacketLength), $packetLength);
+ $packet_offset += $packetLength;
+
+ $otherUsefulData = getid3_lib::BigEndian2Int(substr($MPCheaderData, $packet_offset, 2));
+ $packet_offset += 2;
+ $thisPacket['sample_frequency_raw'] = (($otherUsefulData & 0xE000) >> 13);
+ $thisPacket['max_bands_used'] = (($otherUsefulData & 0x1F00) >> 8);
+ $thisPacket['channels'] = (($otherUsefulData & 0x00F0) >> 4) + 1;
+ $thisPacket['ms_used'] = (bool) (($otherUsefulData & 0x0008) >> 3);
+ $thisPacket['audio_block_frames'] = (($otherUsefulData & 0x0007) >> 0);
+ $thisPacket['sample_frequency'] = $this->MPCfrequencyLookup($thisPacket['sample_frequency_raw']);
+
+ $thisfile_mpc_header['mid_side_stereo'] = $thisPacket['ms_used'];
+ $thisfile_mpc_header['sample_rate'] = $thisPacket['sample_frequency'];
+ $thisfile_mpc_header['samples'] = $thisPacket['sample_count'];
+ $thisfile_mpc_header['stream_version_major'] = $thisPacket['stream_version'];
+
+ $info['audio']['channels'] = $thisPacket['channels'];
+ $info['audio']['sample_rate'] = $thisPacket['sample_frequency'];
+ $info['playtime_seconds'] = $thisPacket['sample_count'] / $thisPacket['sample_frequency'];
+ $info['audio']['bitrate'] = (($info['avdataend'] - $info['avdataoffset']) * 8) / $info['playtime_seconds'];
+ break;
+
+ case 'RG': // Replay Gain
+ $moreBytesToRead = $thisPacket['packet_size'] - $keyNameSize - $maxHandledPacketLength;
+ if ($moreBytesToRead > 0) {
+ $MPCheaderData .= $this->fread($moreBytesToRead);
+ }
+ $thisPacket['replaygain_version'] = getid3_lib::BigEndian2Int(substr($MPCheaderData, $packet_offset, 1));
+ $packet_offset += 1;
+ $thisPacket['replaygain_title_gain'] = getid3_lib::BigEndian2Int(substr($MPCheaderData, $packet_offset, 2));
+ $packet_offset += 2;
+ $thisPacket['replaygain_title_peak'] = getid3_lib::BigEndian2Int(substr($MPCheaderData, $packet_offset, 2));
+ $packet_offset += 2;
+ $thisPacket['replaygain_album_gain'] = getid3_lib::BigEndian2Int(substr($MPCheaderData, $packet_offset, 2));
+ $packet_offset += 2;
+ $thisPacket['replaygain_album_peak'] = getid3_lib::BigEndian2Int(substr($MPCheaderData, $packet_offset, 2));
+ $packet_offset += 2;
+
+ if ($thisPacket['replaygain_title_gain']) { $info['replay_gain']['title']['gain'] = $thisPacket['replaygain_title_gain']; }
+ if ($thisPacket['replaygain_title_peak']) { $info['replay_gain']['title']['peak'] = $thisPacket['replaygain_title_peak']; }
+ if ($thisPacket['replaygain_album_gain']) { $info['replay_gain']['album']['gain'] = $thisPacket['replaygain_album_gain']; }
+ if ($thisPacket['replaygain_album_peak']) { $info['replay_gain']['album']['peak'] = $thisPacket['replaygain_album_peak']; }
+ break;
+
+ case 'EI': // Encoder Info
+ $moreBytesToRead = $thisPacket['packet_size'] - $keyNameSize - $maxHandledPacketLength;
+ if ($moreBytesToRead > 0) {
+ $MPCheaderData .= $this->fread($moreBytesToRead);
+ }
+ $profile_pns = getid3_lib::BigEndian2Int(substr($MPCheaderData, $packet_offset, 1));
+ $packet_offset += 1;
+ $quality_int = (($profile_pns & 0xF0) >> 4);
+ $quality_dec = (($profile_pns & 0x0E) >> 3);
+ $thisPacket['quality'] = (float) $quality_int + ($quality_dec / 8);
+ $thisPacket['pns_tool'] = (bool) (($profile_pns & 0x01) >> 0);
+ $thisPacket['version_major'] = getid3_lib::BigEndian2Int(substr($MPCheaderData, $packet_offset, 1));
+ $packet_offset += 1;
+ $thisPacket['version_minor'] = getid3_lib::BigEndian2Int(substr($MPCheaderData, $packet_offset, 1));
+ $packet_offset += 1;
+ $thisPacket['version_build'] = getid3_lib::BigEndian2Int(substr($MPCheaderData, $packet_offset, 1));
+ $packet_offset += 1;
+ $thisPacket['version'] = $thisPacket['version_major'].'.'.$thisPacket['version_minor'].'.'.$thisPacket['version_build'];
+
+ $info['audio']['encoder'] = 'MPC v'.$thisPacket['version'].' ('.(($thisPacket['version_minor'] % 2) ? 'unstable' : 'stable').')';
+ $thisfile_mpc_header['encoder_version'] = $info['audio']['encoder'];
+ //$thisfile_mpc_header['quality'] = (float) ($thisPacket['quality'] / 1.5875); // values can range from 0.000 to 15.875, mapped to qualities of 0.0 to 10.0
+ $thisfile_mpc_header['quality'] = (float) ($thisPacket['quality'] - 5); // values can range from 0.000 to 15.875, of which 0..4 are "reserved/experimental", and 5..15 are mapped to qualities of 0.0 to 10.0
+ break;
+
+ case 'SO': // Seek Table Offset
+ $packetLength = 0;
+ $thisPacket['seek_table_offset'] = $thisPacket['offset'] + $this->SV8variableLengthInteger(substr($MPCheaderData, $packet_offset, $maxHandledPacketLength), $packetLength);
+ $packet_offset += $packetLength;
+ break;
+
+ case 'ST': // Seek Table
+ case 'SE': // Stream End
+ case 'AP': // Audio Data
+ // nothing useful here, just skip this packet
+ $thisPacket = array();
+ break;
+
+ default:
+ $this->error('Found unhandled key type "'.$thisPacket['key'].'" at offset '.$thisPacket['offset']);
+ return false;
+ break;
+ }
+ if (!empty($thisPacket)) {
+ $info['mpc']['packets'][] = $thisPacket;
+ }
+ $this->fseek($offset);
+ }
+ $thisfile_mpc_header['size'] = $offset;
+ return true;
+ }
+
+ public function ParseMPCsv7() {
+ // this is SV7
+ // http://www.uni-jena.de/~pfk/mpp/sv8/header.html
+
+ $info = &$this->getid3->info;
+ $thisfile_mpc_header = &$info['mpc']['header'];
+ $offset = 0;
+
+ $thisfile_mpc_header['size'] = 28;
+ $MPCheaderData = $info['mpc']['header']['preamble'];
+ $MPCheaderData .= $this->fread($thisfile_mpc_header['size'] - strlen($info['mpc']['header']['preamble']));
+ $offset = strlen('MP+');
+
+ $StreamVersionByte = getid3_lib::LittleEndian2Int(substr($MPCheaderData, $offset, 1));
+ $offset += 1;
+ $thisfile_mpc_header['stream_version_major'] = ($StreamVersionByte & 0x0F) >> 0;
+ $thisfile_mpc_header['stream_version_minor'] = ($StreamVersionByte & 0xF0) >> 4; // should always be 0, subversions no longer exist in SV8
+ $thisfile_mpc_header['frame_count'] = getid3_lib::LittleEndian2Int(substr($MPCheaderData, $offset, 4));
+ $offset += 4;
+
+ if ($thisfile_mpc_header['stream_version_major'] != 7) {
+ $this->error('Only Musepack SV7 supported (this file claims to be v'.$thisfile_mpc_header['stream_version_major'].')');
+ return false;
+ }
+
+ $FlagsDWORD1 = getid3_lib::LittleEndian2Int(substr($MPCheaderData, $offset, 4));
+ $offset += 4;
+ $thisfile_mpc_header['intensity_stereo'] = (bool) (($FlagsDWORD1 & 0x80000000) >> 31);
+ $thisfile_mpc_header['mid_side_stereo'] = (bool) (($FlagsDWORD1 & 0x40000000) >> 30);
+ $thisfile_mpc_header['max_subband'] = ($FlagsDWORD1 & 0x3F000000) >> 24;
+ $thisfile_mpc_header['raw']['profile'] = ($FlagsDWORD1 & 0x00F00000) >> 20;
+ $thisfile_mpc_header['begin_loud'] = (bool) (($FlagsDWORD1 & 0x00080000) >> 19);
+ $thisfile_mpc_header['end_loud'] = (bool) (($FlagsDWORD1 & 0x00040000) >> 18);
+ $thisfile_mpc_header['raw']['sample_rate'] = ($FlagsDWORD1 & 0x00030000) >> 16;
+ $thisfile_mpc_header['max_level'] = ($FlagsDWORD1 & 0x0000FFFF);
+
+ $thisfile_mpc_header['raw']['title_peak'] = getid3_lib::LittleEndian2Int(substr($MPCheaderData, $offset, 2));
+ $offset += 2;
+ $thisfile_mpc_header['raw']['title_gain'] = getid3_lib::LittleEndian2Int(substr($MPCheaderData, $offset, 2), true);
+ $offset += 2;
+
+ $thisfile_mpc_header['raw']['album_peak'] = getid3_lib::LittleEndian2Int(substr($MPCheaderData, $offset, 2));
+ $offset += 2;
+ $thisfile_mpc_header['raw']['album_gain'] = getid3_lib::LittleEndian2Int(substr($MPCheaderData, $offset, 2), true);
+ $offset += 2;
+
+ $FlagsDWORD2 = getid3_lib::LittleEndian2Int(substr($MPCheaderData, $offset, 4));
+ $offset += 4;
+ $thisfile_mpc_header['true_gapless'] = (bool) (($FlagsDWORD2 & 0x80000000) >> 31);
+ $thisfile_mpc_header['last_frame_length'] = ($FlagsDWORD2 & 0x7FF00000) >> 20;
+
+
+ $thisfile_mpc_header['raw']['not_sure_what'] = getid3_lib::LittleEndian2Int(substr($MPCheaderData, $offset, 3));
+ $offset += 3;
+ $thisfile_mpc_header['raw']['encoder_version'] = getid3_lib::LittleEndian2Int(substr($MPCheaderData, $offset, 1));
+ $offset += 1;
+
+ $thisfile_mpc_header['profile'] = $this->MPCprofileNameLookup($thisfile_mpc_header['raw']['profile']);
+ $thisfile_mpc_header['sample_rate'] = $this->MPCfrequencyLookup($thisfile_mpc_header['raw']['sample_rate']);
+ if ($thisfile_mpc_header['sample_rate'] == 0) {
+ $this->error('Corrupt MPC file: frequency == zero');
+ return false;
+ }
+ $info['audio']['sample_rate'] = $thisfile_mpc_header['sample_rate'];
+ $thisfile_mpc_header['samples'] = ((($thisfile_mpc_header['frame_count'] - 1) * 1152) + $thisfile_mpc_header['last_frame_length']) * $info['audio']['channels'];
+
+ $info['playtime_seconds'] = ($thisfile_mpc_header['samples'] / $info['audio']['channels']) / $info['audio']['sample_rate'];
+ if ($info['playtime_seconds'] == 0) {
+ $this->error('Corrupt MPC file: playtime_seconds == zero');
+ return false;
+ }
+
+ // add size of file header to avdataoffset - calc bitrate correctly + MD5 data
+ $info['avdataoffset'] += $thisfile_mpc_header['size'];
+
+ $info['audio']['bitrate'] = (($info['avdataend'] - $info['avdataoffset']) * 8) / $info['playtime_seconds'];
+
+ $thisfile_mpc_header['title_peak'] = $thisfile_mpc_header['raw']['title_peak'];
+ $thisfile_mpc_header['title_peak_db'] = $this->MPCpeakDBLookup($thisfile_mpc_header['title_peak']);
+ if ($thisfile_mpc_header['raw']['title_gain'] < 0) {
+ $thisfile_mpc_header['title_gain_db'] = (float) (32768 + $thisfile_mpc_header['raw']['title_gain']) / -100;
+ } else {
+ $thisfile_mpc_header['title_gain_db'] = (float) $thisfile_mpc_header['raw']['title_gain'] / 100;
+ }
+
+ $thisfile_mpc_header['album_peak'] = $thisfile_mpc_header['raw']['album_peak'];
+ $thisfile_mpc_header['album_peak_db'] = $this->MPCpeakDBLookup($thisfile_mpc_header['album_peak']);
+ if ($thisfile_mpc_header['raw']['album_gain'] < 0) {
+ $thisfile_mpc_header['album_gain_db'] = (float) (32768 + $thisfile_mpc_header['raw']['album_gain']) / -100;
+ } else {
+ $thisfile_mpc_header['album_gain_db'] = (float) $thisfile_mpc_header['raw']['album_gain'] / 100;;
+ }
+ $thisfile_mpc_header['encoder_version'] = $this->MPCencoderVersionLookup($thisfile_mpc_header['raw']['encoder_version']);
+
+ $info['replay_gain']['track']['adjustment'] = $thisfile_mpc_header['title_gain_db'];
+ $info['replay_gain']['album']['adjustment'] = $thisfile_mpc_header['album_gain_db'];
+
+ if ($thisfile_mpc_header['title_peak'] > 0) {
+ $info['replay_gain']['track']['peak'] = $thisfile_mpc_header['title_peak'];
+ } elseif (round($thisfile_mpc_header['max_level'] * 1.18) > 0) {
+ $info['replay_gain']['track']['peak'] = getid3_lib::CastAsInt(round($thisfile_mpc_header['max_level'] * 1.18)); // why? I don't know - see mppdec.c
+ }
+ if ($thisfile_mpc_header['album_peak'] > 0) {
+ $info['replay_gain']['album']['peak'] = $thisfile_mpc_header['album_peak'];
+ }
+
+ //$info['audio']['encoder'] = 'SV'.$thisfile_mpc_header['stream_version_major'].'.'.$thisfile_mpc_header['stream_version_minor'].', '.$thisfile_mpc_header['encoder_version'];
+ $info['audio']['encoder'] = $thisfile_mpc_header['encoder_version'];
+ $info['audio']['encoder_options'] = $thisfile_mpc_header['profile'];
+ $thisfile_mpc_header['quality'] = (float) ($thisfile_mpc_header['raw']['profile'] - 5); // values can range from 0 to 15, of which 0..4 are "reserved/experimental", and 5..15 are mapped to qualities of 0.0 to 10.0
+
+ return true;
+ }
+
+ public function ParseMPCsv6() {
+ // this is SV4 - SV6
+
+ $info = &$this->getid3->info;
+ $thisfile_mpc_header = &$info['mpc']['header'];
+ $offset = 0;
+
+ $thisfile_mpc_header['size'] = 8;
+ $this->fseek($info['avdataoffset']);
+ $MPCheaderData = $this->fread($thisfile_mpc_header['size']);
+
+ // add size of file header to avdataoffset - calc bitrate correctly + MD5 data
+ $info['avdataoffset'] += $thisfile_mpc_header['size'];
+
+ // Most of this code adapted from Jurgen Faul's MPEGplus source code - thanks Jurgen! :)
+ $HeaderDWORD[0] = getid3_lib::LittleEndian2Int(substr($MPCheaderData, 0, 4));
+ $HeaderDWORD[1] = getid3_lib::LittleEndian2Int(substr($MPCheaderData, 4, 4));
+
+
+ // DDDD DDDD CCCC CCCC BBBB BBBB AAAA AAAA
+ // aaaa aaaa abcd dddd dddd deee eeff ffff
+ //
+ // a = bitrate = anything
+ // b = IS = anything
+ // c = MS = anything
+ // d = streamversion = 0000000004 or 0000000005 or 0000000006
+ // e = maxband = anything
+ // f = blocksize = 000001 for SV5+, anything(?) for SV4
+
+ $thisfile_mpc_header['target_bitrate'] = (($HeaderDWORD[0] & 0xFF800000) >> 23);
+ $thisfile_mpc_header['intensity_stereo'] = (bool) (($HeaderDWORD[0] & 0x00400000) >> 22);
+ $thisfile_mpc_header['mid_side_stereo'] = (bool) (($HeaderDWORD[0] & 0x00200000) >> 21);
+ $thisfile_mpc_header['stream_version_major'] = ($HeaderDWORD[0] & 0x001FF800) >> 11;
+ $thisfile_mpc_header['stream_version_minor'] = 0; // no sub-version numbers before SV7
+ $thisfile_mpc_header['max_band'] = ($HeaderDWORD[0] & 0x000007C0) >> 6; // related to lowpass frequency, not sure how it translates exactly
+ $thisfile_mpc_header['block_size'] = ($HeaderDWORD[0] & 0x0000003F);
+
+ switch ($thisfile_mpc_header['stream_version_major']) {
+ case 4:
+ $thisfile_mpc_header['frame_count'] = ($HeaderDWORD[1] >> 16);
+ break;
+
+ case 5:
+ case 6:
+ $thisfile_mpc_header['frame_count'] = $HeaderDWORD[1];
+ break;
+
+ default:
+ $info['error'] = 'Expecting 4, 5 or 6 in version field, found '.$thisfile_mpc_header['stream_version_major'].' instead';
+ unset($info['mpc']);
+ return false;
+ break;
+ }
+
+ if (($thisfile_mpc_header['stream_version_major'] > 4) && ($thisfile_mpc_header['block_size'] != 1)) {
+ $this->warning('Block size expected to be 1, actual value found: '.$thisfile_mpc_header['block_size']);
+ }
+
+ $thisfile_mpc_header['sample_rate'] = 44100; // AB: used by all files up to SV7
+ $info['audio']['sample_rate'] = $thisfile_mpc_header['sample_rate'];
+ $thisfile_mpc_header['samples'] = $thisfile_mpc_header['frame_count'] * 1152 * $info['audio']['channels'];
+
+ if ($thisfile_mpc_header['target_bitrate'] == 0) {
+ $info['audio']['bitrate_mode'] = 'vbr';
+ } else {
+ $info['audio']['bitrate_mode'] = 'cbr';
+ }
+
+ $info['mpc']['bitrate'] = ($info['avdataend'] - $info['avdataoffset']) * 8 * 44100 / $thisfile_mpc_header['frame_count'] / 1152;
+ $info['audio']['bitrate'] = $info['mpc']['bitrate'];
+ $info['audio']['encoder'] = 'SV'.$thisfile_mpc_header['stream_version_major'];
+
+ return true;
+ }
+
+
+ public function MPCprofileNameLookup($profileid) {
+ static $MPCprofileNameLookup = array(
+ 0 => 'no profile',
+ 1 => 'Experimental',
+ 2 => 'unused',
+ 3 => 'unused',
+ 4 => 'unused',
+ 5 => 'below Telephone (q = 0.0)',
+ 6 => 'below Telephone (q = 1.0)',
+ 7 => 'Telephone (q = 2.0)',
+ 8 => 'Thumb (q = 3.0)',
+ 9 => 'Radio (q = 4.0)',
+ 10 => 'Standard (q = 5.0)',
+ 11 => 'Extreme (q = 6.0)',
+ 12 => 'Insane (q = 7.0)',
+ 13 => 'BrainDead (q = 8.0)',
+ 14 => 'above BrainDead (q = 9.0)',
+ 15 => 'above BrainDead (q = 10.0)'
+ );
+ return (isset($MPCprofileNameLookup[$profileid]) ? $MPCprofileNameLookup[$profileid] : 'invalid');
+ }
+
+ public function MPCfrequencyLookup($frequencyid) {
+ static $MPCfrequencyLookup = array(
+ 0 => 44100,
+ 1 => 48000,
+ 2 => 37800,
+ 3 => 32000
+ );
+ return (isset($MPCfrequencyLookup[$frequencyid]) ? $MPCfrequencyLookup[$frequencyid] : 'invalid');
+ }
+
+ public function MPCpeakDBLookup($intvalue) {
+ if ($intvalue > 0) {
+ return ((log10($intvalue) / log10(2)) - 15) * 6;
+ }
+ return false;
+ }
+
+ public function MPCencoderVersionLookup($encoderversion) {
+ //Encoder version * 100 (106 = 1.06)
+ //EncoderVersion % 10 == 0 Release (1.0)
+ //EncoderVersion % 2 == 0 Beta (1.06)
+ //EncoderVersion % 2 == 1 Alpha (1.05a...z)
+
+ if ($encoderversion == 0) {
+ // very old version, not known exactly which
+ return 'Buschmann v1.7.0-v1.7.9 or Klemm v0.90-v1.05';
+ }
+
+ if (($encoderversion % 10) == 0) {
+
+ // release version
+ return number_format($encoderversion / 100, 2);
+
+ } elseif (($encoderversion % 2) == 0) {
+
+ // beta version
+ return number_format($encoderversion / 100, 2).' beta';
+
+ }
+
+ // alpha version
+ return number_format($encoderversion / 100, 2).' alpha';
+ }
+
+ public function SV8variableLengthInteger($data, &$packetLength, $maxHandledPacketLength=9) {
+ $packet_size = 0;
+ for ($packetLength = 1; $packetLength <= $maxHandledPacketLength; $packetLength++) {
+ // variable-length size field:
+ // bits, big-endian
+ // 0xxx xxxx - value 0 to 2^7-1
+ // 1xxx xxxx 0xxx xxxx - value 0 to 2^14-1
+ // 1xxx xxxx 1xxx xxxx 0xxx xxxx - value 0 to 2^21-1
+ // 1xxx xxxx 1xxx xxxx 1xxx xxxx 0xxx xxxx - value 0 to 2^28-1
+ // ...
+ $thisbyte = ord(substr($data, ($packetLength - 1), 1));
+ // look through bytes until find a byte with MSB==0
+ $packet_size = ($packet_size << 7);
+ $packet_size = ($packet_size | ($thisbyte & 0x7F));
+ if (($thisbyte & 0x80) === 0) {
+ break;
+ }
+ if ($packetLength >= $maxHandledPacketLength) {
+ return false;
+ }
+ }
+ return $packet_size;
+ }
+
+ public function MPCsv8PacketName($packetKey) {
+ static $MPCsv8PacketName = array();
+ if (empty($MPCsv8PacketName)) {
+ $MPCsv8PacketName = array(
+ 'AP' => 'Audio Packet',
+ 'CT' => 'Chapter Tag',
+ 'EI' => 'Encoder Info',
+ 'RG' => 'Replay Gain',
+ 'SE' => 'Stream End',
+ 'SH' => 'Stream Header',
+ 'SO' => 'Seek Table Offset',
+ 'ST' => 'Seek Table',
+ );
+ }
+ return (isset($MPCsv8PacketName[$packetKey]) ? $MPCsv8PacketName[$packetKey] : $packetKey);
+ }
+}
scripts.mit.edu / autoinstallsdev / mediawiki.git / blobdiff