<?php ///////////////////////////////////////////////////////////////// /// getID3() by James Heinrich <info@getid3.org> // // available at https://github.com/JamesHeinrich/getID3 // // or https://www.getid3.org // // or http://getid3.sourceforge.net // // see readme.txt for more details // ///////////////////////////////////////////////////////////////// // // // module.audio.ac3.php // // module for analyzing AC-3 (aka Dolby Digital) audio files // // dependencies: NONE // // /// ///////////////////////////////////////////////////////////////// if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers exit; } class getid3_ac3 extends getid3_handler { /** * @var array */ private $AC3header = array(); /** * @var int */ private $BSIoffset = 0; const syncword = 0x0B77; /** * @return bool */ public function Analyze() { $info = &$this->getid3->info; ///AH $info['ac3']['raw']['bsi'] = array(); $thisfile_ac3 = &$info['ac3']; $thisfile_ac3_raw = &$thisfile_ac3['raw']; $thisfile_ac3_raw_bsi = &$thisfile_ac3_raw['bsi']; // http://www.atsc.org/standards/a_52a.pdf $info['fileformat'] = 'ac3'; // An AC-3 serial coded audio bit stream is made up of a sequence of synchronization frames // Each synchronization frame contains 6 coded audio blocks (AB), each of which represent 256 // new audio samples per channel. A synchronization information (SI) header at the beginning // of each frame contains information needed to acquire and maintain synchronization. A // bit stream information (BSI) header follows SI, and contains parameters describing the coded // audio service. The coded audio blocks may be followed by an auxiliary data (Aux) field. At the // end of each frame is an error check field that includes a CRC word for error detection. An // additional CRC word is located in the SI header, the use of which, by a decoder, is optional. // // syncinfo() | bsi() | AB0 | AB1 | AB2 | AB3 | AB4 | AB5 | Aux | CRC // syncinfo() { // syncword 16 // crc1 16 // fscod 2 // frmsizecod 6 // } /* end of syncinfo */ $this->fseek($info['avdataoffset']); $tempAC3header = $this->fread(100); // should be enough to cover all data, there are some variable-length fields...? $this->AC3header['syncinfo'] = getid3_lib::BigEndian2Int(substr($tempAC3header, 0, 2)); $this->AC3header['bsi'] = getid3_lib::BigEndian2Bin(substr($tempAC3header, 2)); $thisfile_ac3_raw_bsi['bsid'] = (getid3_lib::LittleEndian2Int(substr($tempAC3header, 5, 1)) & 0xF8) >> 3; // AC3 and E-AC3 put the "bsid" version identifier in the same place, but unfortnately the 4 bytes between the syncword and the version identifier are interpreted differently, so grab it here so the following code structure can make sense unset($tempAC3header); if ($this->AC3header['syncinfo'] !== self::syncword) { if (!$this->isDependencyFor('matroska')) { unset($info['fileformat'], $info['ac3']); return $this->error('Expecting "'.dechex(self::syncword).'" at offset '.$info['avdataoffset'].', found "'.dechex($this->AC3header['syncinfo']).'"'); } } $info['audio']['dataformat'] = 'ac3'; $info['audio']['bitrate_mode'] = 'cbr'; $info['audio']['lossless'] = false; if ($thisfile_ac3_raw_bsi['bsid'] <= 8) { $thisfile_ac3_raw_bsi['crc1'] = getid3_lib::Bin2Dec($this->readHeaderBSI(16)); $thisfile_ac3_raw_bsi['fscod'] = $this->readHeaderBSI(2); // 5.4.1.3 $thisfile_ac3_raw_bsi['frmsizecod'] = $this->readHeaderBSI(6); // 5.4.1.4 if ($thisfile_ac3_raw_bsi['frmsizecod'] > 37) { // binary: 100101 - see Table 5.18 Frame Size Code Table (1 word = 16 bits) $this->warning('Unexpected ac3.bsi.frmsizecod value: '.$thisfile_ac3_raw_bsi['frmsizecod'].', bitrate not set correctly'); } $thisfile_ac3_raw_bsi['bsid'] = $this->readHeaderBSI(5); // we already know this from pre-parsing the version identifier, but re-read it to let the bitstream flow as intended $thisfile_ac3_raw_bsi['bsmod'] = $this->readHeaderBSI(3); $thisfile_ac3_raw_bsi['acmod'] = $this->readHeaderBSI(3); if ($thisfile_ac3_raw_bsi['acmod'] & 0x01) { // If the lsb of acmod is a 1, center channel is in use and cmixlev follows in the bit stream. $thisfile_ac3_raw_bsi['cmixlev'] = $this->readHeaderBSI(2); $thisfile_ac3['center_mix_level'] = self::centerMixLevelLookup($thisfile_ac3_raw_bsi['cmixlev']); } if ($thisfile_ac3_raw_bsi['acmod'] & 0x04) { // If the msb of acmod is a 1, surround channels are in use and surmixlev follows in the bit stream. $thisfile_ac3_raw_bsi['surmixlev'] = $this->readHeaderBSI(2); $thisfile_ac3['surround_mix_level'] = self::surroundMixLevelLookup($thisfile_ac3_raw_bsi['surmixlev']); } if ($thisfile_ac3_raw_bsi['acmod'] == 0x02) { // When operating in the two channel mode, this 2-bit code indicates whether or not the program has been encoded in Dolby Surround. $thisfile_ac3_raw_bsi['dsurmod'] = $this->readHeaderBSI(2); $thisfile_ac3['dolby_surround_mode'] = self::dolbySurroundModeLookup($thisfile_ac3_raw_bsi['dsurmod']); } $thisfile_ac3_raw_bsi['flags']['lfeon'] = (bool) $this->readHeaderBSI(1); // This indicates how far the average dialogue level is below digital 100 percent. Valid values are 1-31. // The value of 0 is reserved. The values of 1 to 31 are interpreted as -1 dB to -31 dB with respect to digital 100 percent. $thisfile_ac3_raw_bsi['dialnorm'] = $this->readHeaderBSI(5); // 5.4.2.8 dialnorm: Dialogue Normalization, 5 Bits $thisfile_ac3_raw_bsi['flags']['compr'] = (bool) $this->readHeaderBSI(1); // 5.4.2.9 compre: Compression Gain Word Exists, 1 Bit if ($thisfile_ac3_raw_bsi['flags']['compr']) { $thisfile_ac3_raw_bsi['compr'] = $this->readHeaderBSI(8); // 5.4.2.10 compr: Compression Gain Word, 8 Bits $thisfile_ac3['heavy_compression'] = self::heavyCompression($thisfile_ac3_raw_bsi['compr']); } $thisfile_ac3_raw_bsi['flags']['langcod'] = (bool) $this->readHeaderBSI(1); // 5.4.2.11 langcode: Language Code Exists, 1 Bit if ($thisfile_ac3_raw_bsi['flags']['langcod']) { $thisfile_ac3_raw_bsi['langcod'] = $this->readHeaderBSI(8); // 5.4.2.12 langcod: Language Code, 8 Bits } $thisfile_ac3_raw_bsi['flags']['audprodinfo'] = (bool) $this->readHeaderBSI(1); // 5.4.2.13 audprodie: Audio Production Information Exists, 1 Bit if ($thisfile_ac3_raw_bsi['flags']['audprodinfo']) { $thisfile_ac3_raw_bsi['mixlevel'] = $this->readHeaderBSI(5); // 5.4.2.14 mixlevel: Mixing Level, 5 Bits $thisfile_ac3_raw_bsi['roomtyp'] = $this->readHeaderBSI(2); // 5.4.2.15 roomtyp: Room Type, 2 Bits $thisfile_ac3['mixing_level'] = (80 + $thisfile_ac3_raw_bsi['mixlevel']).'dB'; $thisfile_ac3['room_type'] = self::roomTypeLookup($thisfile_ac3_raw_bsi['roomtyp']); } $thisfile_ac3_raw_bsi['dialnorm2'] = $this->readHeaderBSI(5); // 5.4.2.16 dialnorm2: Dialogue Normalization, ch2, 5 Bits $thisfile_ac3['dialogue_normalization2'] = '-'.$thisfile_ac3_raw_bsi['dialnorm2'].'dB'; // This indicates how far the average dialogue level is below digital 100 percent. Valid values are 1-31. The value of 0 is reserved. The values of 1 to 31 are interpreted as -1 dB to -31 dB with respect to digital 100 percent. $thisfile_ac3_raw_bsi['flags']['compr2'] = (bool) $this->readHeaderBSI(1); // 5.4.2.17 compr2e: Compression Gain Word Exists, ch2, 1 Bit if ($thisfile_ac3_raw_bsi['flags']['compr2']) { $thisfile_ac3_raw_bsi['compr2'] = $this->readHeaderBSI(8); // 5.4.2.18 compr2: Compression Gain Word, ch2, 8 Bits $thisfile_ac3['heavy_compression2'] = self::heavyCompression($thisfile_ac3_raw_bsi['compr2']); } $thisfile_ac3_raw_bsi['flags']['langcod2'] = (bool) $this->readHeaderBSI(1); // 5.4.2.19 langcod2e: Language Code Exists, ch2, 1 Bit if ($thisfile_ac3_raw_bsi['flags']['langcod2']) { $thisfile_ac3_raw_bsi['langcod2'] = $this->readHeaderBSI(8); // 5.4.2.20 langcod2: Language Code, ch2, 8 Bits } $thisfile_ac3_raw_bsi['flags']['audprodinfo2'] = (bool) $this->readHeaderBSI(1); // 5.4.2.21 audprodi2e: Audio Production Information Exists, ch2, 1 Bit if ($thisfile_ac3_raw_bsi['flags']['audprodinfo2']) { $thisfile_ac3_raw_bsi['mixlevel2'] = $this->readHeaderBSI(5); // 5.4.2.22 mixlevel2: Mixing Level, ch2, 5 Bits $thisfile_ac3_raw_bsi['roomtyp2'] = $this->readHeaderBSI(2); // 5.4.2.23 roomtyp2: Room Type, ch2, 2 Bits $thisfile_ac3['mixing_level2'] = (80 + $thisfile_ac3_raw_bsi['mixlevel2']).'dB'; $thisfile_ac3['room_type2'] = self::roomTypeLookup($thisfile_ac3_raw_bsi['roomtyp2']); } $thisfile_ac3_raw_bsi['copyright'] = (bool) $this->readHeaderBSI(1); // 5.4.2.24 copyrightb: Copyright Bit, 1 Bit $thisfile_ac3_raw_bsi['original'] = (bool) $this->readHeaderBSI(1); // 5.4.2.25 origbs: Original Bit Stream, 1 Bit $thisfile_ac3_raw_bsi['flags']['timecod1'] = $this->readHeaderBSI(2); // 5.4.2.26 timecod1e, timcode2e: Time Code (first and second) Halves Exist, 2 Bits if ($thisfile_ac3_raw_bsi['flags']['timecod1'] & 0x01) { $thisfile_ac3_raw_bsi['timecod1'] = $this->readHeaderBSI(14); // 5.4.2.27 timecod1: Time code first half, 14 bits $thisfile_ac3['timecode1'] = 0; $thisfile_ac3['timecode1'] += (($thisfile_ac3_raw_bsi['timecod1'] & 0x3E00) >> 9) * 3600; // The first 5 bits of this 14-bit field represent the time in hours, with valid values of 0�23 $thisfile_ac3['timecode1'] += (($thisfile_ac3_raw_bsi['timecod1'] & 0x01F8) >> 3) * 60; // The next 6 bits represent the time in minutes, with valid values of 0�59 $thisfile_ac3['timecode1'] += (($thisfile_ac3_raw_bsi['timecod1'] & 0x0003) >> 0) * 8; // The final 3 bits represents the time in 8 second increments, with valid values of 0�7 (representing 0, 8, 16, ... 56 seconds) } if ($thisfile_ac3_raw_bsi['flags']['timecod1'] & 0x02) { $thisfile_ac3_raw_bsi['timecod2'] = $this->readHeaderBSI(14); // 5.4.2.28 timecod2: Time code second half, 14 bits $thisfile_ac3['timecode2'] = 0; $thisfile_ac3['timecode2'] += (($thisfile_ac3_raw_bsi['timecod2'] & 0x3800) >> 11) * 1; // The first 3 bits of this 14-bit field represent the time in seconds, with valid values from 0�7 (representing 0-7 seconds) $thisfile_ac3['timecode2'] += (($thisfile_ac3_raw_bsi['timecod2'] & 0x07C0) >> 6) * (1 / 30); // The next 5 bits represents the time in frames, with valid values from 0�29 (one frame = 1/30th of a second) $thisfile_ac3['timecode2'] += (($thisfile_ac3_raw_bsi['timecod2'] & 0x003F) >> 0) * ((1 / 30) / 60); // The final 6 bits represents fractions of 1/64 of a frame, with valid values from 0�63 } $thisfile_ac3_raw_bsi['flags']['addbsi'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['addbsi']) { $thisfile_ac3_raw_bsi['addbsi_length'] = $this->readHeaderBSI(6) + 1; // This 6-bit code, which exists only if addbside is a 1, indicates the length in bytes of additional bit stream information. The valid range of addbsil is 0�63, indicating 1�64 additional bytes, respectively. $this->AC3header['bsi'] .= getid3_lib::BigEndian2Bin($this->fread($thisfile_ac3_raw_bsi['addbsi_length'])); $thisfile_ac3_raw_bsi['addbsi_data'] = substr($this->AC3header['bsi'], $this->BSIoffset, $thisfile_ac3_raw_bsi['addbsi_length'] * 8); $this->BSIoffset += $thisfile_ac3_raw_bsi['addbsi_length'] * 8; } } elseif ($thisfile_ac3_raw_bsi['bsid'] <= 16) { // E-AC3 $this->error('E-AC3 parsing is incomplete and experimental in this version of getID3 ('.$this->getid3->version().'). Notably the bitrate calculations are wrong -- value might (or not) be correct, but it is not calculated correctly. Email info@getid3.org if you know how to calculate EAC3 bitrate correctly.'); $info['audio']['dataformat'] = 'eac3'; $thisfile_ac3_raw_bsi['strmtyp'] = $this->readHeaderBSI(2); $thisfile_ac3_raw_bsi['substreamid'] = $this->readHeaderBSI(3); $thisfile_ac3_raw_bsi['frmsiz'] = $this->readHeaderBSI(11); $thisfile_ac3_raw_bsi['fscod'] = $this->readHeaderBSI(2); if ($thisfile_ac3_raw_bsi['fscod'] == 3) { $thisfile_ac3_raw_bsi['fscod2'] = $this->readHeaderBSI(2); $thisfile_ac3_raw_bsi['numblkscod'] = 3; // six blocks per syncframe } else { $thisfile_ac3_raw_bsi['numblkscod'] = $this->readHeaderBSI(2); } $thisfile_ac3['bsi']['blocks_per_sync_frame'] = self::blocksPerSyncFrame($thisfile_ac3_raw_bsi['numblkscod']); $thisfile_ac3_raw_bsi['acmod'] = $this->readHeaderBSI(3); $thisfile_ac3_raw_bsi['flags']['lfeon'] = (bool) $this->readHeaderBSI(1); $thisfile_ac3_raw_bsi['bsid'] = $this->readHeaderBSI(5); // we already know this from pre-parsing the version identifier, but re-read it to let the bitstream flow as intended $thisfile_ac3_raw_bsi['dialnorm'] = $this->readHeaderBSI(5); $thisfile_ac3_raw_bsi['flags']['compr'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['compr']) { $thisfile_ac3_raw_bsi['compr'] = $this->readHeaderBSI(8); } if ($thisfile_ac3_raw_bsi['acmod'] == 0) { // if 1+1 mode (dual mono, so some items need a second value) $thisfile_ac3_raw_bsi['dialnorm2'] = $this->readHeaderBSI(5); $thisfile_ac3_raw_bsi['flags']['compr2'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['compr2']) { $thisfile_ac3_raw_bsi['compr2'] = $this->readHeaderBSI(8); } } if ($thisfile_ac3_raw_bsi['strmtyp'] == 1) { // if dependent stream $thisfile_ac3_raw_bsi['flags']['chanmap'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['chanmap']) { $thisfile_ac3_raw_bsi['chanmap'] = $this->readHeaderBSI(8); } } $thisfile_ac3_raw_bsi['flags']['mixmdat'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['mixmdat']) { // Mixing metadata if ($thisfile_ac3_raw_bsi['acmod'] > 2) { // if more than 2 channels $thisfile_ac3_raw_bsi['dmixmod'] = $this->readHeaderBSI(2); } if (($thisfile_ac3_raw_bsi['acmod'] & 0x01) && ($thisfile_ac3_raw_bsi['acmod'] > 2)) { // if three front channels exist $thisfile_ac3_raw_bsi['ltrtcmixlev'] = $this->readHeaderBSI(3); $thisfile_ac3_raw_bsi['lorocmixlev'] = $this->readHeaderBSI(3); } if ($thisfile_ac3_raw_bsi['acmod'] & 0x04) { // if a surround channel exists $thisfile_ac3_raw_bsi['ltrtsurmixlev'] = $this->readHeaderBSI(3); $thisfile_ac3_raw_bsi['lorosurmixlev'] = $this->readHeaderBSI(3); } if ($thisfile_ac3_raw_bsi['flags']['lfeon']) { // if the LFE channel exists $thisfile_ac3_raw_bsi['flags']['lfemixlevcod'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['lfemixlevcod']) { $thisfile_ac3_raw_bsi['lfemixlevcod'] = $this->readHeaderBSI(5); } } if ($thisfile_ac3_raw_bsi['strmtyp'] == 0) { // if independent stream $thisfile_ac3_raw_bsi['flags']['pgmscl'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['pgmscl']) { $thisfile_ac3_raw_bsi['pgmscl'] = $this->readHeaderBSI(6); } if ($thisfile_ac3_raw_bsi['acmod'] == 0) { // if 1+1 mode (dual mono, so some items need a second value) $thisfile_ac3_raw_bsi['flags']['pgmscl2'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['pgmscl2']) { $thisfile_ac3_raw_bsi['pgmscl2'] = $this->readHeaderBSI(6); } } $thisfile_ac3_raw_bsi['flags']['extpgmscl'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['extpgmscl']) { $thisfile_ac3_raw_bsi['extpgmscl'] = $this->readHeaderBSI(6); } $thisfile_ac3_raw_bsi['mixdef'] = $this->readHeaderBSI(2); if ($thisfile_ac3_raw_bsi['mixdef'] == 1) { // mixing option 2 $thisfile_ac3_raw_bsi['premixcmpsel'] = (bool) $this->readHeaderBSI(1); $thisfile_ac3_raw_bsi['drcsrc'] = (bool) $this->readHeaderBSI(1); $thisfile_ac3_raw_bsi['premixcmpscl'] = $this->readHeaderBSI(3); } elseif ($thisfile_ac3_raw_bsi['mixdef'] == 2) { // mixing option 3 $thisfile_ac3_raw_bsi['mixdata'] = $this->readHeaderBSI(12); } elseif ($thisfile_ac3_raw_bsi['mixdef'] == 3) { // mixing option 4 $mixdefbitsread = 0; $thisfile_ac3_raw_bsi['mixdeflen'] = $this->readHeaderBSI(5); $mixdefbitsread += 5; $thisfile_ac3_raw_bsi['flags']['mixdata2'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['mixdata2']) { $thisfile_ac3_raw_bsi['premixcmpsel'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; $thisfile_ac3_raw_bsi['drcsrc'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; $thisfile_ac3_raw_bsi['premixcmpscl'] = $this->readHeaderBSI(3); $mixdefbitsread += 3; $thisfile_ac3_raw_bsi['flags']['extpgmlscl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['extpgmlscl']) { $thisfile_ac3_raw_bsi['extpgmlscl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4; } $thisfile_ac3_raw_bsi['flags']['extpgmcscl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['extpgmcscl']) { $thisfile_ac3_raw_bsi['extpgmcscl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4; } $thisfile_ac3_raw_bsi['flags']['extpgmrscl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['extpgmrscl']) { $thisfile_ac3_raw_bsi['extpgmrscl'] = $this->readHeaderBSI(4); } $thisfile_ac3_raw_bsi['flags']['extpgmlsscl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['extpgmlsscl']) { $thisfile_ac3_raw_bsi['extpgmlsscl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4; } $thisfile_ac3_raw_bsi['flags']['extpgmrsscl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['extpgmrsscl']) { $thisfile_ac3_raw_bsi['extpgmrsscl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4; } $thisfile_ac3_raw_bsi['flags']['extpgmlfescl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['extpgmlfescl']) { $thisfile_ac3_raw_bsi['extpgmlfescl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4; } $thisfile_ac3_raw_bsi['flags']['dmixscl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['dmixscl']) { $thisfile_ac3_raw_bsi['dmixscl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4; } $thisfile_ac3_raw_bsi['flags']['addch'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['addch']) { $thisfile_ac3_raw_bsi['flags']['extpgmaux1scl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['extpgmaux1scl']) { $thisfile_ac3_raw_bsi['extpgmaux1scl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4; } $thisfile_ac3_raw_bsi['flags']['extpgmaux2scl'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['extpgmaux2scl']) { $thisfile_ac3_raw_bsi['extpgmaux2scl'] = $this->readHeaderBSI(4); $mixdefbitsread += 4; } } } $thisfile_ac3_raw_bsi['flags']['mixdata3'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['mixdata3']) { $thisfile_ac3_raw_bsi['spchdat'] = $this->readHeaderBSI(5); $mixdefbitsread += 5; $thisfile_ac3_raw_bsi['flags']['addspchdat'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['addspchdat']) { $thisfile_ac3_raw_bsi['spchdat1'] = $this->readHeaderBSI(5); $mixdefbitsread += 5; $thisfile_ac3_raw_bsi['spchan1att'] = $this->readHeaderBSI(2); $mixdefbitsread += 2; $thisfile_ac3_raw_bsi['flags']['addspchdat1'] = (bool) $this->readHeaderBSI(1); $mixdefbitsread += 1; if ($thisfile_ac3_raw_bsi['flags']['addspchdat1']) { $thisfile_ac3_raw_bsi['spchdat2'] = $this->readHeaderBSI(5); $mixdefbitsread += 5; $thisfile_ac3_raw_bsi['spchan2att'] = $this->readHeaderBSI(3); $mixdefbitsread += 3; } } } $mixdata_bits = (8 * ($thisfile_ac3_raw_bsi['mixdeflen'] + 2)) - $mixdefbitsread; $mixdata_fill = (($mixdata_bits % 8) ? 8 - ($mixdata_bits % 8) : 0); $thisfile_ac3_raw_bsi['mixdata'] = $this->readHeaderBSI($mixdata_bits); $thisfile_ac3_raw_bsi['mixdatafill'] = $this->readHeaderBSI($mixdata_fill); unset($mixdefbitsread, $mixdata_bits, $mixdata_fill); } if ($thisfile_ac3_raw_bsi['acmod'] < 2) { // if mono or dual mono source $thisfile_ac3_raw_bsi['flags']['paninfo'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['paninfo']) { $thisfile_ac3_raw_bsi['panmean'] = $this->readHeaderBSI(8); $thisfile_ac3_raw_bsi['paninfo'] = $this->readHeaderBSI(6); } if ($thisfile_ac3_raw_bsi['acmod'] == 0) { // if 1+1 mode (dual mono, so some items need a second value) $thisfile_ac3_raw_bsi['flags']['paninfo2'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['paninfo2']) { $thisfile_ac3_raw_bsi['panmean2'] = $this->readHeaderBSI(8); $thisfile_ac3_raw_bsi['paninfo2'] = $this->readHeaderBSI(6); } } } $thisfile_ac3_raw_bsi['flags']['frmmixcfginfo'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['frmmixcfginfo']) { // mixing configuration information if ($thisfile_ac3_raw_bsi['numblkscod'] == 0) { $thisfile_ac3_raw_bsi['blkmixcfginfo'][0] = $this->readHeaderBSI(5); } else { for ($blk = 0; $blk < $thisfile_ac3_raw_bsi['numblkscod']; $blk++) { $thisfile_ac3_raw_bsi['flags']['blkmixcfginfo'.$blk] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['blkmixcfginfo'.$blk]) { // mixing configuration information $thisfile_ac3_raw_bsi['blkmixcfginfo'][$blk] = $this->readHeaderBSI(5); } } } } } } $thisfile_ac3_raw_bsi['flags']['infomdat'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['infomdat']) { // Informational metadata $thisfile_ac3_raw_bsi['bsmod'] = $this->readHeaderBSI(3); $thisfile_ac3_raw_bsi['flags']['copyrightb'] = (bool) $this->readHeaderBSI(1); $thisfile_ac3_raw_bsi['flags']['origbs'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['acmod'] == 2) { // if in 2/0 mode $thisfile_ac3_raw_bsi['dsurmod'] = $this->readHeaderBSI(2); $thisfile_ac3_raw_bsi['dheadphonmod'] = $this->readHeaderBSI(2); } if ($thisfile_ac3_raw_bsi['acmod'] >= 6) { // if both surround channels exist $thisfile_ac3_raw_bsi['dsurexmod'] = $this->readHeaderBSI(2); } $thisfile_ac3_raw_bsi['flags']['audprodi'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['audprodi']) { $thisfile_ac3_raw_bsi['mixlevel'] = $this->readHeaderBSI(5); $thisfile_ac3_raw_bsi['roomtyp'] = $this->readHeaderBSI(2); $thisfile_ac3_raw_bsi['flags']['adconvtyp'] = (bool) $this->readHeaderBSI(1); } if ($thisfile_ac3_raw_bsi['acmod'] == 0) { // if 1+1 mode (dual mono, so some items need a second value) $thisfile_ac3_raw_bsi['flags']['audprodi2'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['audprodi2']) { $thisfile_ac3_raw_bsi['mixlevel2'] = $this->readHeaderBSI(5); $thisfile_ac3_raw_bsi['roomtyp2'] = $this->readHeaderBSI(2); $thisfile_ac3_raw_bsi['flags']['adconvtyp2'] = (bool) $this->readHeaderBSI(1); } } if ($thisfile_ac3_raw_bsi['fscod'] < 3) { // if not half sample rate $thisfile_ac3_raw_bsi['flags']['sourcefscod'] = (bool) $this->readHeaderBSI(1); } } if (($thisfile_ac3_raw_bsi['strmtyp'] == 0) && ($thisfile_ac3_raw_bsi['numblkscod'] != 3)) { // if both surround channels exist $thisfile_ac3_raw_bsi['flags']['convsync'] = (bool) $this->readHeaderBSI(1); } if ($thisfile_ac3_raw_bsi['strmtyp'] == 2) { // if bit stream converted from AC-3 if ($thisfile_ac3_raw_bsi['numblkscod'] != 3) { // 6 blocks per syncframe $thisfile_ac3_raw_bsi['flags']['blkid'] = 1; } else { $thisfile_ac3_raw_bsi['flags']['blkid'] = (bool) $this->readHeaderBSI(1); } if ($thisfile_ac3_raw_bsi['flags']['blkid']) { $thisfile_ac3_raw_bsi['frmsizecod'] = $this->readHeaderBSI(6); } } $thisfile_ac3_raw_bsi['flags']['addbsi'] = (bool) $this->readHeaderBSI(1); if ($thisfile_ac3_raw_bsi['flags']['addbsi']) { $thisfile_ac3_raw_bsi['addbsil'] = $this->readHeaderBSI(6); $thisfile_ac3_raw_bsi['addbsi'] = $this->readHeaderBSI(($thisfile_ac3_raw_bsi['addbsil'] + 1) * 8); } } else { $this->error('Bit stream identification is version '.$thisfile_ac3_raw_bsi['bsid'].', but getID3() only understands up to version 16. Please submit a support ticket with a sample file.'); unset($info['ac3']); return false; } if (isset($thisfile_ac3_raw_bsi['fscod2'])) { $thisfile_ac3['sample_rate'] = self::sampleRateCodeLookup2($thisfile_ac3_raw_bsi['fscod2']); } else { $thisfile_ac3['sample_rate'] = self::sampleRateCodeLookup($thisfile_ac3_raw_bsi['fscod']); } if ($thisfile_ac3_raw_bsi['fscod'] <= 3) { $info['audio']['sample_rate'] = $thisfile_ac3['sample_rate']; } else { $this->warning('Unexpected ac3.bsi.fscod value: '.$thisfile_ac3_raw_bsi['fscod']); } if (isset($thisfile_ac3_raw_bsi['frmsizecod'])) { $thisfile_ac3['frame_length'] = self::frameSizeLookup($thisfile_ac3_raw_bsi['frmsizecod'], $thisfile_ac3_raw_bsi['fscod']); $thisfile_ac3['bitrate'] = self::bitrateLookup($thisfile_ac3_raw_bsi['frmsizecod']); } elseif (!empty($thisfile_ac3_raw_bsi['frmsiz'])) { // this isn't right, but it's (usually) close, roughly 5% less than it should be. // but WHERE is the actual bitrate value stored in EAC3?? email info@getid3.org if you know! $thisfile_ac3['bitrate'] = ($thisfile_ac3_raw_bsi['frmsiz'] + 1) * 16 * 30; // The frmsiz field shall contain a value one less than the overall size of the coded syncframe in 16-bit words. That is, this field may assume a value ranging from 0 to 2047, and these values correspond to syncframe sizes ranging from 1 to 2048. // kludge-fix to make it approximately the expected value, still not "right": $thisfile_ac3['bitrate'] = round(($thisfile_ac3['bitrate'] * 1.05) / 16000) * 16000; } $info['audio']['bitrate'] = $thisfile_ac3['bitrate']; if (isset($thisfile_ac3_raw_bsi['bsmod']) && isset($thisfile_ac3_raw_bsi['acmod'])) { $thisfile_ac3['service_type'] = self::serviceTypeLookup($thisfile_ac3_raw_bsi['bsmod'], $thisfile_ac3_raw_bsi['acmod']); } $ac3_coding_mode = self::audioCodingModeLookup($thisfile_ac3_raw_bsi['acmod']); foreach($ac3_coding_mode as $key => $value) { $thisfile_ac3[$key] = $value; } switch ($thisfile_ac3_raw_bsi['acmod']) { case 0: case 1: $info['audio']['channelmode'] = 'mono'; break; case 3: case 4: $info['audio']['channelmode'] = 'stereo'; break; default: $info['audio']['channelmode'] = 'surround'; break; } $info['audio']['channels'] = $thisfile_ac3['num_channels']; $thisfile_ac3['lfe_enabled'] = $thisfile_ac3_raw_bsi['flags']['lfeon']; if ($thisfile_ac3_raw_bsi['flags']['lfeon']) { $info['audio']['channels'] .= '.1'; } $thisfile_ac3['channels_enabled'] = self::channelsEnabledLookup($thisfile_ac3_raw_bsi['acmod'], $thisfile_ac3_raw_bsi['flags']['lfeon']); $thisfile_ac3['dialogue_normalization'] = '-'.$thisfile_ac3_raw_bsi['dialnorm'].'dB'; return true; } /** * @param int $length * * @return int */ private function readHeaderBSI($length) { $data = substr($this->AC3header['bsi'], $this->BSIoffset, $length); $this->BSIoffset += $length; return bindec($data); } /** * @param int $fscod * * @return int|string|false */ public static function sampleRateCodeLookup($fscod) { static $sampleRateCodeLookup = array( 0 => 48000, 1 => 44100, 2 => 32000, 3 => 'reserved' // If the reserved code is indicated, the decoder should not attempt to decode audio and should mute. ); return (isset($sampleRateCodeLookup[$fscod]) ? $sampleRateCodeLookup[$fscod] : false); } /** * @param int $fscod2 * * @return int|string|false */ public static function sampleRateCodeLookup2($fscod2) { static $sampleRateCodeLookup2 = array( 0 => 24000, 1 => 22050, 2 => 16000, 3 => 'reserved' // If the reserved code is indicated, the decoder should not attempt to decode audio and should mute. ); return (isset($sampleRateCodeLookup2[$fscod2]) ? $sampleRateCodeLookup2[$fscod2] : false); } /** * @param int $bsmod * @param int $acmod * * @return string|false */ public static function serviceTypeLookup($bsmod, $acmod) { static $serviceTypeLookup = array(); if (empty($serviceTypeLookup)) { for ($i = 0; $i <= 7; $i++) { $serviceTypeLookup[0][$i] = 'main audio service: complete main (CM)'; $serviceTypeLookup[1][$i] = 'main audio service: music and effects (ME)'; $serviceTypeLookup[2][$i] = 'associated service: visually impaired (VI)'; $serviceTypeLookup[3][$i] = 'associated service: hearing impaired (HI)'; $serviceTypeLookup[4][$i] = 'associated service: dialogue (D)'; $serviceTypeLookup[5][$i] = 'associated service: commentary (C)'; $serviceTypeLookup[6][$i] = 'associated service: emergency (E)'; } $serviceTypeLookup[7][1] = 'associated service: voice over (VO)'; for ($i = 2; $i <= 7; $i++) { $serviceTypeLookup[7][$i] = 'main audio service: karaoke'; } } return (isset($serviceTypeLookup[$bsmod][$acmod]) ? $serviceTypeLookup[$bsmod][$acmod] : false); } /** * @param int $acmod * * @return array|false */ public static function audioCodingModeLookup($acmod) { // array(channel configuration, # channels (not incl LFE), channel order) static $audioCodingModeLookup = array ( 0 => array('channel_config'=>'1+1', 'num_channels'=>2, 'channel_order'=>'Ch1,Ch2'), 1 => array('channel_config'=>'1/0', 'num_channels'=>1, 'channel_order'=>'C'), 2 => array('channel_config'=>'2/0', 'num_channels'=>2, 'channel_order'=>'L,R'), 3 => array('channel_config'=>'3/0', 'num_channels'=>3, 'channel_order'=>'L,C,R'), 4 => array('channel_config'=>'2/1', 'num_channels'=>3, 'channel_order'=>'L,R,S'), 5 => array('channel_config'=>'3/1', 'num_channels'=>4, 'channel_order'=>'L,C,R,S'), 6 => array('channel_config'=>'2/2', 'num_channels'=>4, 'channel_order'=>'L,R,SL,SR'), 7 => array('channel_config'=>'3/2', 'num_channels'=>5, 'channel_order'=>'L,C,R,SL,SR'), ); return (isset($audioCodingModeLookup[$acmod]) ? $audioCodingModeLookup[$acmod] : false); } /** * @param int $cmixlev * * @return int|float|string|false */ public static function centerMixLevelLookup($cmixlev) { static $centerMixLevelLookup; if (empty($centerMixLevelLookup)) { $centerMixLevelLookup = array( 0 => pow(2, -3.0 / 6), // 0.707 (-3.0 dB) 1 => pow(2, -4.5 / 6), // 0.595 (-4.5 dB) 2 => pow(2, -6.0 / 6), // 0.500 (-6.0 dB) 3 => 'reserved' ); } return (isset($centerMixLevelLookup[$cmixlev]) ? $centerMixLevelLookup[$cmixlev] : false); } /** * @param int $surmixlev * * @return int|float|string|false */ public static function surroundMixLevelLookup($surmixlev) { static $surroundMixLevelLookup; if (empty($surroundMixLevelLookup)) { $surroundMixLevelLookup = array( 0 => pow(2, -3.0 / 6), 1 => pow(2, -6.0 / 6), 2 => 0, 3 => 'reserved' ); } return (isset($surroundMixLevelLookup[$surmixlev]) ? $surroundMixLevelLookup[$surmixlev] : false); } /** * @param int $dsurmod * * @return string|false */ public static function dolbySurroundModeLookup($dsurmod) { static $dolbySurroundModeLookup = array( 0 => 'not indicated', 1 => 'Not Dolby Surround encoded', 2 => 'Dolby Surround encoded', 3 => 'reserved' ); return (isset($dolbySurroundModeLookup[$dsurmod]) ? $dolbySurroundModeLookup[$dsurmod] : false); } /** * @param int $acmod * @param bool $lfeon * * @return array */ public static function channelsEnabledLookup($acmod, $lfeon) { $lookup = array( 'ch1'=>($acmod == 0), 'ch2'=>($acmod == 0), 'left'=>($acmod > 1), 'right'=>($acmod > 1), 'center'=>(bool) ($acmod & 0x01), 'surround_mono'=>false, 'surround_left'=>false, 'surround_right'=>false, 'lfe'=>$lfeon); switch ($acmod) { case 4: case 5: $lookup['surround_mono'] = true; break; case 6: case 7: $lookup['surround_left'] = true; $lookup['surround_right'] = true; break; } return $lookup; } /** * @param int $compre * * @return float|int */ public static function heavyCompression($compre) { // The first four bits indicate gain changes in 6.02dB increments which can be // implemented with an arithmetic shift operation. The following four bits // indicate linear gain changes, and require a 5-bit multiply. // We will represent the two 4-bit fields of compr as follows: // X0 X1 X2 X3 . Y4 Y5 Y6 Y7 // The meaning of the X values is most simply described by considering X to represent a 4-bit // signed integer with values from -8 to +7. The gain indicated by X is then (X + 1) * 6.02 dB. The // following table shows this in detail. // Meaning of 4 msb of compr // 7 +48.16 dB // 6 +42.14 dB // 5 +36.12 dB // 4 +30.10 dB // 3 +24.08 dB // 2 +18.06 dB // 1 +12.04 dB // 0 +6.02 dB // -1 0 dB // -2 -6.02 dB // -3 -12.04 dB // -4 -18.06 dB // -5 -24.08 dB // -6 -30.10 dB // -7 -36.12 dB // -8 -42.14 dB $fourbit = str_pad(decbin(($compre & 0xF0) >> 4), 4, '0', STR_PAD_LEFT); if ($fourbit[0] == '1') { $log_gain = -8 + bindec(substr($fourbit, 1)); } else { $log_gain = bindec(substr($fourbit, 1)); } $log_gain = ($log_gain + 1) * getid3_lib::RGADamplitude2dB(2); // The value of Y is a linear representation of a gain change of up to -6 dB. Y is considered to // be an unsigned fractional integer, with a leading value of 1, or: 0.1 Y4 Y5 Y6 Y7 (base 2). Y can // represent values between 0.111112 (or 31/32) and 0.100002 (or 1/2). Thus, Y can represent gain // changes from -0.28 dB to -6.02 dB. $lin_gain = (16 + ($compre & 0x0F)) / 32; // The combination of X and Y values allows compr to indicate gain changes from // 48.16 - 0.28 = +47.89 dB, to // -42.14 - 6.02 = -48.16 dB. return $log_gain - $lin_gain; } /** * @param int $roomtyp * * @return string|false */ public static function roomTypeLookup($roomtyp) { static $roomTypeLookup = array( 0 => 'not indicated', 1 => 'large room, X curve monitor', 2 => 'small room, flat monitor', 3 => 'reserved' ); return (isset($roomTypeLookup[$roomtyp]) ? $roomTypeLookup[$roomtyp] : false); } /** * @param int $frmsizecod * @param int $fscod * * @return int|false */ public static function frameSizeLookup($frmsizecod, $fscod) { // LSB is whether padding is used or not $padding = (bool) ($frmsizecod & 0x01); $framesizeid = ($frmsizecod & 0x3E) >> 1; static $frameSizeLookup = array(); if (empty($frameSizeLookup)) { $frameSizeLookup = array ( 0 => array( 128, 138, 192), // 32 kbps 1 => array( 160, 174, 240), // 40 kbps 2 => array( 192, 208, 288), // 48 kbps 3 => array( 224, 242, 336), // 56 kbps 4 => array( 256, 278, 384), // 64 kbps 5 => array( 320, 348, 480), // 80 kbps 6 => array( 384, 416, 576), // 96 kbps 7 => array( 448, 486, 672), // 112 kbps 8 => array( 512, 556, 768), // 128 kbps 9 => array( 640, 696, 960), // 160 kbps 10 => array( 768, 834, 1152), // 192 kbps 11 => array( 896, 974, 1344), // 224 kbps 12 => array(1024, 1114, 1536), // 256 kbps 13 => array(1280, 1392, 1920), // 320 kbps 14 => array(1536, 1670, 2304), // 384 kbps 15 => array(1792, 1950, 2688), // 448 kbps 16 => array(2048, 2228, 3072), // 512 kbps 17 => array(2304, 2506, 3456), // 576 kbps 18 => array(2560, 2786, 3840) // 640 kbps ); } $paddingBytes = 0; if (($fscod == 1) && $padding) { // frame lengths are padded by 1 word (16 bits) at 44100 // (fscode==1) means 44100Hz (see sampleRateCodeLookup) $paddingBytes = 2; } return (isset($frameSizeLookup[$framesizeid][$fscod]) ? $frameSizeLookup[$framesizeid][$fscod] + $paddingBytes : false); } /** * @param int $frmsizecod * * @return int|false */ public static function bitrateLookup($frmsizecod) { // LSB is whether padding is used or not $padding = (bool) ($frmsizecod & 0x01); $framesizeid = ($frmsizecod & 0x3E) >> 1; static $bitrateLookup = array( 0 => 32000, 1 => 40000, 2 => 48000, 3 => 56000, 4 => 64000, 5 => 80000, 6 => 96000, 7 => 112000, 8 => 128000, 9 => 160000, 10 => 192000, 11 => 224000, 12 => 256000, 13 => 320000, 14 => 384000, 15 => 448000, 16 => 512000, 17 => 576000, 18 => 640000, ); return (isset($bitrateLookup[$framesizeid]) ? $bitrateLookup[$framesizeid] : false); } /** * @param int $numblkscod * * @return int|false */ public static function blocksPerSyncFrame($numblkscod) { static $blocksPerSyncFrameLookup = array( 0 => 1, 1 => 2, 2 => 3, 3 => 6, ); return (isset($blocksPerSyncFrameLookup[$numblkscod]) ? $blocksPerSyncFrameLookup[$numblkscod] : false); } }

تفاعل

ثورة تكنولوجيا تغزو المدن…وتحول نمط الحياة

مايو 23, 2025

8٬652 2 دقائق

كتبت ميرنا أشرف

في سباق متسارع نحو المستقبل، لم تعد التكنولوجيا الذكية مجرد أدوات نستخدمها، بل أصبحت شريكًا أساسيًا في تفاصيل حياتنا اليومية. ومع هذا التطور، اقتحمت التكنولوجيا قلب المدن، لتقود تحولًا كبيراً من المدن التقليدية إلى مدن ذكية تُدار بأنظمة رقمية متقدمة. وكان من أبرز ملامح هذا التحول: أتمتة الشبكات الكهربائية، لتتحول بدورها إلى شبكات ذكية قادرة على إدارة وتوزيع الطاقة بكفاءة داخل المدن الذكية، بما يواكب تسارع متطلبات العصر ويعزز الاستدامة.

أكد المهندس أشرف جمعة، صاحب شركات ألفا مصر للطاقة الشمسية، أن المدن الذكية تعد مجتمعات حضارية تتميز بتكامل الخدمات وإدارتها وتقديمها عن طريق التكامل واستخدامات تطبيقات التكنولوجيا الحديثة.

وتابع، يتم تحويل المدن الحضارية إلى مدن ذكية منذ البدء عن طريق تقديم حلول تكنولوجية عالية الدقة وفائقة السرعة، ويتم إدارتها أوتوماتيكياً عن طريق غرف تحكم مركزية، لسرعة تنفيذ المهام واكتشاف الأعطال والمشاكل، وتقديم حلول مستدامة، وقابلة للتطبيق، وموافقة مع البيئة الخضراء.

أضاف جمعة، أنه يتم إدارة الشبكات الكهربائية في المدن الذكية عن طريق شبكة اتصالات عالية الدقة، لربط أنظمة المستشعرات بمكونات باقي الأنظمة، لاستقبال وإرسال الأوامر أوتوماتيكياً، لتنفيذ وتحديد الاعطال والمهام.

كيف تعمل أنظمة الإضاءة الذكية على تقليل استهلاك الطاقة؟

بين جمعة، أنه عندما يتم تحديد المشكلة بشكل صحيح، يتم وضع عدة حلول تعتمد على الكفاءة لاقتصادية، ولذلك يتم دائما تقديم حلول جذرية ومستدامة وتعمل على تقليل تكاليف الاستهلاك، وبالتالي تعظيم الاستفادة بأقل تكاليف ممكنة، مثل: استخدام كشافات الإضاءة بمستشعرات التحرك للعنصر البشري لتحديد أوقات الذروة وأوقات تقليل الأحمال الكهربائية، وهذا ما تم فعله في طريق شرم الشيخ ومدخل مدينة شرم الشيخ، وبعض الكمبوندات في العاصمة الإدارية الجديدة، عن طريق تكنولوجيا الطاقة الشمسية التي تم العمل عليها وإنتاجها خلال الفترات الأخيرة.

مضيفا، إلى أن شبكات الكهرباء من الأنظمة التي تمتد لآلاف الكيلومترات داخل المدن الذكية، وهي التي تربط المدن داخل بعضها البعض، وهي الأعين التي يرى بها الناس الطرق، وما داخل المدن والمنازل.

ولذلك فإن إدارة شبكات الكهرباء شيء بالغ التعقيد، ويحتاج إلى تكنولوجيا عالية لمراقبة وتحديد أماكن الأحمال العالية، وتحديد أوقات الذروة، وكذلك تحقيق وفر من الاستخدام الجيد لشبكة الكهرباء.

متطلبات تشغيل الشبكات

ومن جانبها قالت المهندسة رحمة الديب، تابعة لشركة الفا للطاقة الشمسية، إن المكونات اللازمة لإدارة تلك الشبكات بأنظمة الذكاء الاصطناعي تعتمد على التكنولوجيا المتقدمة من كمبيوترات فائقة السرعة، وشبكة اتصالات عالية، وكذلك عنصراً بشريا ذو تدريب عال لاستخدام هذه الوسائل لتحقيق التكامل بين لعناصر.

أوضحت الديب، أن من أبرز التحديات التي قد تواجه تنفيذ تلك الشبكات الذكية في المدن، هي التكاليف العالية لهذه الشبكات، بالإضافة إلى عائق البنية التحتية القديمة، التي تحتاج إلى استبدال مكونات الشبكة القديمة بالشبكة الحديثة.

اتفق الطرفان علي أن مصر لا زالت قائمة لإدخال نظام تكنولوجيا الشبكات الذكية، والقضاء على فكرة عوائق البنية التحتية القديمة، مشيرة إلى أن مصر تبني حاليا خمس مدن ذكية، منها: المنصورة الجديدة، العاصمة الإدارية، العلمين، وغيرها.

ونلاحظ أن مصر دخلت بقوة في مجال تحسين الشبكات القديمة وإدخال تعديلات عليها لتحسين كفاءة استخدام الطاقة.

وأشارت الديب، إلى أن العائد الاقتصادي الأعلى يتحقق من الوفر الناتج عن تغيير نمط الاستهلاك، ولعل من أبرز الأمثلة، أن هناك مدينة كانت تستهلك أكثر من 5 جيجا وات في الإضاءة فقط، وتم تقليل هذا الاستهلاك إلى 1 جيجا فقط بعد استخدام تلك الأنظمة، مما وفر على الدولة 75% من كافة عناصر التكاليف (استيراد بترول أو غاز، كابلات نقل الطاقة، لوحات كهربائية، محولات… إلخ)

في ظل هذا التوجه المتسارع نحو تطوير البنية التحتية الذكية، تبدو المدن الذكية ليست مجرد خيار مستقبلي، بل ضرورة أصبحت اجبارية لمواكبة التحديات البيئية والاقتصادية. ومع الجهود المستمرة التي تبذلها الدول والقطاع الخاص في مصر، تتعزز فرص التحول إلى نموذج حضاري متكامل، يعتمد على التكنولوجيا المتقدمة .

مايو 23, 2025

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