1<?php 2 3///////////////////////////////////////////////////////////////// 4/// getID3() by James Heinrich <info@getid3.org> // 5// available at https://github.com/JamesHeinrich/getID3 // 6// or https://www.getid3.org // 7// or http://getid3.sourceforge.net // 8// see readme.txt for more details // 9///////////////////////////////////////////////////////////////// 10// // 11// module.audio.dss.php // 12// module for analyzing Digital Speech Standard (DSS) files // 13// dependencies: NONE // 14// /// 15///////////////////////////////////////////////////////////////// 16 17if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers 18 exit; 19} 20 21class getid3_dss extends getid3_handler 22{ 23 /** 24 * @return bool 25 */ 26 public function Analyze() { 27 $info = &$this->getid3->info; 28 29 $this->fseek($info['avdataoffset']); 30 $DSSheader = $this->fread(1540); 31 32 if (!preg_match('#^[\\x02-\\x08]ds[s2]#', $DSSheader)) { 33 $this->error('Expecting "[02-08] 64 73 [73|32]" at offset '.$info['avdataoffset'].', found "'.getid3_lib::PrintHexBytes(substr($DSSheader, 0, 4)).'"'); 34 return false; 35 } 36 37 // some structure information taken from http://cpansearch.perl.org/src/RGIBSON/Audio-DSS-0.02/lib/Audio/DSS.pm 38 $info['encoding'] = 'ISO-8859-1'; // not certain, but assumed 39 $info['dss'] = array(); 40 41 $info['fileformat'] = 'dss'; 42 $info['mime_type'] = 'audio/x-'.substr($DSSheader, 1, 3); // "audio/x-dss" or "audio/x-ds2" 43 $info['audio']['dataformat'] = substr($DSSheader, 1, 3); // "dss" or "ds2" 44 $info['audio']['bitrate_mode'] = 'cbr'; 45 46 $info['dss']['version'] = ord(substr($DSSheader, 0, 1)); 47 $info['dss']['hardware'] = trim(substr($DSSheader, 12, 16)); // identification string for hardware used to create the file, e.g. "DPM 9600", "DS2400" 48 $info['dss']['unknown1'] = getid3_lib::LittleEndian2Int(substr($DSSheader, 28, 4)); 49 // 32-37 = "FE FF FE FF F7 FF" in all the sample files I've seen 50 $info['dss']['date_create_unix'] = $this->DSSdateStringToUnixDate(substr($DSSheader, 38, 12)); 51 $info['dss']['date_complete_unix'] = $this->DSSdateStringToUnixDate(substr($DSSheader, 50, 12)); 52 $info['dss']['playtime_sec'] = ((int) substr($DSSheader, 62, 2) * 3600) + ((int) substr($DSSheader, 64, 2) * 60) + (int) substr($DSSheader, 66, 2); // approximate file playtime in HHMMSS 53 if ($info['dss']['version'] <= 3) { 54 $info['dss']['playtime_ms'] = getid3_lib::LittleEndian2Int(substr($DSSheader, 512, 4)); // exact file playtime in milliseconds. Has also been observed at offset 530 in one sample file, with something else (unknown) at offset 512 55 $info['dss']['priority'] = ord(substr($DSSheader, 793, 1)); 56 $info['dss']['comments'] = trim(substr($DSSheader, 798, 100)); 57 $info['dss']['sample_rate_index'] = ord(substr($DSSheader, 1538, 1)); // this isn't certain, this may or may not be where the sample rate info is stored, but it seems consistent on my small selection of sample files 58 $info['audio']['sample_rate'] = $this->DSSsampleRateLookup($info['dss']['sample_rate_index']); 59 } else { 60 $this->getid3->warning('DSS above version 3 not fully supported in this version of getID3. Any additional documentation or format specifications would be welcome. This file is version '.$info['dss']['version']); 61 } 62 63 $info['audio']['bits_per_sample'] = 16; // maybe, maybe not -- most compressed audio formats don't have a fixed bits-per-sample value, but this is a reasonable approximation 64 $info['audio']['channels'] = 1; 65 66 if (!empty($info['dss']['playtime_ms']) && (floor($info['dss']['playtime_ms'] / 1000) == $info['dss']['playtime_sec'])) { // *should* just be playtime_ms / 1000 but at least one sample file has playtime_ms at offset 530 instead of offset 512, so safety check 67 $info['playtime_seconds'] = $info['dss']['playtime_ms'] / 1000; 68 } else { 69 $info['playtime_seconds'] = $info['dss']['playtime_sec']; 70 if (!empty($info['dss']['playtime_ms'])) { 71 $this->getid3->warning('playtime_ms ('.number_format($info['dss']['playtime_ms'] / 1000, 3).') does not match playtime_sec ('.number_format($info['dss']['playtime_sec']).') - using playtime_sec value'); 72 } 73 } 74 $info['audio']['bitrate'] = ($info['filesize'] * 8) / $info['playtime_seconds']; 75 76 return true; 77 } 78 79 /** 80 * @param string $datestring 81 * 82 * @return int|false 83 */ 84 public function DSSdateStringToUnixDate($datestring) { 85 $y = (int) substr($datestring, 0, 2); 86 $m = substr($datestring, 2, 2); 87 $d = substr($datestring, 4, 2); 88 $h = substr($datestring, 6, 2); 89 $i = substr($datestring, 8, 2); 90 $s = substr($datestring, 10, 2); 91 $y += (($y < 95) ? 2000 : 1900); 92 return mktime($h, $i, $s, $m, $d, $y); 93 } 94 95 /** 96 * @param int $sample_rate_index 97 * 98 * @return int|false 99 */ 100 public function DSSsampleRateLookup($sample_rate_index) { 101 static $dssSampleRateLookup = array( 102 0x0A => 16000, 103 0x0C => 11025, 104 0x0D => 12000, 105 0x15 => 8000, 106 ); 107 if (!array_key_exists($sample_rate_index, $dssSampleRateLookup)) { 108 $this->getid3->warning('unknown sample_rate_index: 0x'.strtoupper(dechex($sample_rate_index))); 109 return false; 110 } 111 return $dssSampleRateLookup[$sample_rate_index]; 112 } 113 114} 115