name : module.audio.dss.php <?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.dss.php // // module for analyzing Digital Speech Standard (DSS) files // // dependencies: NONE // // /// ///////////////////////////////////////////////////////////////// if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers exit; } class getid3_dss extends getid3_handler { /** * @return bool */ public function Analyze() { $info = &$this->getid3->info; $this->fseek($info['avdataoffset']); $DSSheader = $this->fread(1540); if (!preg_match('#^[\\x02-\\x08]ds[s2]#', $DSSheader)) { $this->error('Expecting "[02-08] 64 73 [73|32]" at offset '.$info['avdataoffset'].', found "'.getid3_lib::PrintHexBytes(substr($DSSheader, 0, 4)).'"'); return false; } // some structure information taken from http://cpansearch.perl.org/src/RGIBSON/Audio-DSS-0.02/lib/Audio/DSS.pm $info['encoding'] = 'ISO-8859-1'; // not certain, but assumed $info['dss'] = array(); $info['fileformat'] = 'dss'; $info['mime_type'] = 'audio/x-'.substr($DSSheader, 1, 3); // "audio/x-dss" or "audio/x-ds2" $info['audio']['dataformat'] = substr($DSSheader, 1, 3); // "dss" or "ds2" $info['audio']['bitrate_mode'] = 'cbr'; $info['dss']['version'] = ord(substr($DSSheader, 0, 1)); $info['dss']['hardware'] = trim(substr($DSSheader, 12, 16)); // identification string for hardware used to create the file, e.g. "DPM 9600", "DS2400" $info['dss']['unknown1'] = getid3_lib::LittleEndian2Int(substr($DSSheader, 28, 4)); // 32-37 = "FE FF FE FF F7 FF" in all the sample files I've seen $info['dss']['date_create_unix'] = $this->DSSdateStringToUnixDate(substr($DSSheader, 38, 12)); $info['dss']['date_complete_unix'] = $this->DSSdateStringToUnixDate(substr($DSSheader, 50, 12)); $info['dss']['playtime_sec'] = ((int) substr($DSSheader, 62, 2) * 3600) + ((int) substr($DSSheader, 64, 2) * 60) + (int) substr($DSSheader, 66, 2); // approximate file playtime in HHMMSS if ($info['dss']['version'] <= 3) { $info['dss']['playtime_ms'] = getid3_lib::LittleEndian2Int(substr($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 $info['dss']['priority'] = ord(substr($DSSheader, 793, 1)); $info['dss']['comments'] = trim(substr($DSSheader, 798, 100)); $info['dss']['sample_rate_index'] = ord(substr($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 $info['audio']['sample_rate'] = $this->DSSsampleRateLookup($info['dss']['sample_rate_index']); } else { $this->getid3->warning('DSS above version 3 not fully supported in this version of getID3. Any additional documentation or format specifications would be welcome. This file is version '.$info['dss']['version']); } $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 $info['audio']['channels'] = 1; if (!empty($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 $info['playtime_seconds'] = $info['dss']['playtime_ms'] / 1000; } else { $info['playtime_seconds'] = $info['dss']['playtime_sec']; if (!empty($info['dss']['playtime_ms'])) { $this->getid3->warning('playtime_ms ('.number_format($info['dss']['playtime_ms'] / 1000, 3).') does not match playtime_sec ('.number_format($info['dss']['playtime_sec']).') - using playtime_sec value'); } } $info['audio']['bitrate'] = ($info['filesize'] * 8) / $info['playtime_seconds']; return true; } /** * @param string $datestring * * @return int|false */ public function DSSdateStringToUnixDate($datestring) { $y = (int) substr($datestring, 0, 2); $m = substr($datestring, 2, 2); $d = substr($datestring, 4, 2); $h = substr($datestring, 6, 2); $i = substr($datestring, 8, 2); $s = substr($datestring, 10, 2); $y += (($y < 95) ? 2000 : 1900); return mktime($h, $i, $s, $m, $d, $y); } /** * @param int $sample_rate_index * * @return int|false */ public function DSSsampleRateLookup($sample_rate_index) { static $dssSampleRateLookup = array( 0x0A => 16000, 0x0C => 11025, 0x0D => 12000, 0x15 => 8000, ); if (!array_key_exists($sample_rate_index, $dssSampleRateLookup)) { $this->getid3->warning('unknown sample_rate_index: 0x'.strtoupper(dechex($sample_rate_index))); return false; } return $dssSampleRateLookup[$sample_rate_index]; } }