這篇文章主要介紹了PHP獲取音頻文件的相關信息的相關資料，非常的實用，有需要的小伙伴可以參考下。
項目需求：現在有一個音頻文件上傳的功能，在上傳後PHP需要獲取這個音頻文件的相關信息，例如：時長等，由於這個文件是放在買的空間上的，沒有像ffmpeg這樣的擴展來處理，那麼PHP能不能獲取到這些信息?
下面是之前在項目中用到的一個用PHP進行音頻文件頭部信息的讀取與寫入操作的實現，主要針對 WMA 和 MP3 兩種格式，供參考。
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'` can not been overwritten', E_USER_WARNING); return false; } $handler = &$this->_get_handler($file); if (!$handler) return false; return $handler->set_info($file, $pa); } // private methods function &_get_handler($file) { $ext = strtolower(strrchr($file, '.')); $ret = false; if ($ext == '.mp3') { // MP3 $ret = &$this->_mp3; if (!$ret) $ret = new _Mp3Exif(); } else if ($ext == '.wma') { // wma $ret = &$this->_wma; if (!$ret) $ret = new _WmaExif(); } else { // unknown trigger_error('AudioExif not supported `' . $ext . '` file.', E_USER_WARNING); } return $ret; } } // DBCS => gb2312 function dbcs_gbk($str) { // strip the last " " $str = substr($str, 0, -2); return mb_convert_encoding($str, 'GBK', 'UCS-2LE'); } // gb2312 => DBCS function gbk_dbcs($str) { $str = mb_convert_encoding($str, 'UCS-2LE', 'GBK'); $str .= " "; return $str; } // file exif class _AudioExif { var $fd; var $head; var $head_off; var $head_buf; // init the file handler function _file_init($fpath, $write = false) { $mode = ($write ? 'rb+' : 'rb'); $this->fd = @fopen($fpath, $mode); if (!$this->fd) { trigger_error('AudioExif: `' . $fpath . '` can not be opened with mode `' . $mode . '`', E_USER_WARNING); return false; } $this->head = false; $this->head_off = 0; $this->head_buf = ''; return true; } // read buffer from the head_buf & move the off pointer function _read_head_buf($len) { if ($len <= 0) return NULL; $buf = substr($this->head_buf, $this->head_off, $len); $this->head_off += strlen($buf); return $buf; } // read one short value function _read_head_short() { $ord1 = ord(substr($this->head_buf, $this->head_off, 1)); $ord2 = ord(substr($this->head_buf, $this->head_off+1, 1)); $this->head_off += 2; return ($ord1 + ($ord2<<8)); } // save the file head function _file_save($head, $olen, $nlen = 0) { if ($nlen == 0) $nlen = strlen($head); if ($nlen == $olen) { // shorter flock($this->fd, LOCK_EX); fseek($this->fd, 0, SEEK_SET); fwrite($this->fd, $head, $nlen); flock($this->fd, LOCK_UN); } else { // longer, buffer required $stat = fstat($this->fd); $fsize = $stat['size']; // buf required (4096?) 應該不會 nlen - olen > 4096 吧 $woff = 0; $roff = $olen; // read first buffer flock($this->fd, LOCK_EX); fseek($this->fd, $roff, SEEK_SET); $buf = fread($this->fd, 4096); // seek to start fseek($this->fd, $woff, SEEK_SET); fwrite($this->fd, $head, $nlen); $woff += $nlen; // seek to woff & write the data do { $buf2 = $buf; $roff += 4096; if ($roff < $fsize) { fseek($this->fd, $roff, SEEK_SET); $buf = fread($this->fd, 4096); } // save last buffer $len2 = strlen($buf2); fseek($this->fd, $woff, SEEK_SET); fwrite($this->fd, $buf2, $len2); $woff += $len2; } while ($roff < $fsize); ftruncate($this->fd, $woff); flock($this->fd, LOCK_UN); } } // close the file function _file_deinit() { if ($this->fd) { fclose($this->fd); $this->fd = false; } } } // wma class class _WmaExif extends _AudioExif { var $items1 = array('Title', 'Artist', 'Copyright', 'Description', 'Reserved'); var $items2 = array('Year', 'Genre', 'AlbumTitle'); // check file size (length) maybe invalid file function check_size($file) { $ret = false; if (!$this->_file_init($file)) return true; if ($this->_init_header()) { $buf = fread($this->fd, 24); $tmp = unpack('H32id/Vlen/H8unused', $buf); if ($tmp['id'] == '3626b2758e66cf11a6d900aa0062ce6c') { $stat = fstat($this->fd); $ret = ($stat['size'] == ($this->head['len'] + $tmp['len'])); } } $this->_file_deinit(); return $ret; } // set info (save the infos) function set_info($file, $pa) { // check the pa settype($pa, 'array'); if (!$this->_file_init($file, true)) return false; if (!$this->_init_header()) { $this->_file_deinit(); return false; } // parse the old header & generate the new header $head_body = ''; $st_found = $ex_found = false; $head_num = $this->head['num']; while (($tmp = $this->_get_head_frame()) && ($head_num > 0)) { $head_num--; if ($tmp['id'] == '3326b2758e66cf11a6d900aa0062ce6c') { // Standard Info // 1-4 $st_found = true; $st_body1 = $st_body2 = ''; $lenx = unpack('v5', $this->_read_head_buf(10)); $tmp['len'] -= 34; // 10 + 24 for ($i = 0; $i < count($this->items1); $i++) { $l = $lenx[$i+1]; $k = $this->items1[$i]; $tmp['len'] -= $l; $data = $this->_read_head_buf($l); if (isset($pa[$k])) $data = gbk_dbcs($pa[$k]); $st_body2 .= $data; $st_body1 .= pack('v', strlen($data)); } // left length if ($tmp['len'] > 0) $st_body2 .= $this->_read_head_buf($tmp['len']); // save to head_body $head_body .= pack('H32VH8', $tmp['id'], strlen($st_body1 . $st_body2)+24, $tmp['unused']); $head_body .= $st_body1 . $st_body2; $st_body2 .= $data; } // save to head_body $head_body .= pack('H32Va4', '3326b2758e66cf11a6d900aa0062ce6c', strlen($st_body1 . $st_body2)+24, ''); $head_body .= $st_body1 . $st_body2; $this->head['num']++; } // ex not found? if (!$ex_found) { $inum = 0; $et_body = ''; foreach ($this->items2 as $k) { $nbuf = gbk_dbcs('WM/' . $k); $vbuf = (isset($pa[$k]) ? gbk_dbcs($pa[$k]) : ""); $et_body .= pack('v', strlen($nbuf)) . $nbuf . pack('vv', 0, strlen($vbuf)) . $vbuf; $inum++; } $head_body .= pack('H32Va4v', '40a4d0d207e3d21197f000a0c95ea850', strlen($et_body)+26, '', $inum); $head_body .= $et_body; $this->head['num']++; } // after save $new_len = strlen($head_body) + 30; $old_len = $this->head['len']; if ($new_len < $old_len) { $head_body .= str_repeat(" ", $old_len - $new_len); $new_len = $old_len; } $tmp = $this->head; $head_buf = pack('H32VVVH4', $tmp['id'], $new_len, $tmp['len2'], $tmp['num'], $tmp['unused']); $head_buf .= $head_body; $this->_file_save($head_buf, $old_len, $new_len); // close the file & return $this->_file_deinit(); return true; } // get info function get_info($file) { $ret = array(); if (!$this->_file_init($file)) return false; if (!$this->_init_header()) { $this->_file_deinit(); return false; } // get the data from head_buf $head_num = $this->head['num']; // num of head_frame while (($tmp = $this->_get_head_frame()) && $head_num > 0) { $head_num--; if ($tmp['id'] == '3326b2758e66cf11a6d900aa0062ce6c') { // Standard Info $lenx = unpack('v*', $this->_read_head_buf(10)); for ($i = 1; $i <= count($this->items1); $i++) { $k = $this->items1[$i-1]; $ret[$k] = dbcs_gbk($this->_read_head_buf($lenx[$i])); } } else if ($tmp['id'] == '40a4d0d207e3d21197f000a0c95ea850') { // Extended Info $inum = $this->_read_head_short(); $tmp['len'] -= 26; while ($inum > 0 && $tmp['len'] > 0) { // attribute name $nlen = $this->_read_head_short(); $nbuf = $this->_read_head_buf($nlen); // the flag & value length $flag = $this->_read_head_short(); $vlen = $this->_read_head_short(); $vbuf = $this->_read_head_buf($vlen); // update the XX $tmp['len'] -= (6 + $nlen + $vlen); $inum--; $name = dbcs_gbk($nbuf); $k = substr($name, 3); if (in_array($k, $this->items2)) { // all is string value (refer to falg for other tags) $ret[$k] = dbcs_gbk($vbuf); } } } else { // skip only if ($tmp['len'] > 24) $this->head_off += ($tmp['len'] - 24); } } $this->_file_deinit(); return $ret; } // get the header? function _init_header() { fseek($this->fd, 0, SEEK_SET); $buf = fread($this->fd, 30); if (strlen($buf) != 30) return false; $tmp = unpack('H32id/Vlen/Vlen2/Vnum/H4unused', $buf); if ($tmp['id'] != '3026b2758e66cf11a6d900aa0062ce6c') return false; $this->head_buf = fread($this->fd, $tmp['len'] - 30); $this->head = $tmp; return true; } // _get_head_frame() function _get_head_frame() { $buf = $this->_read_head_buf(24); if (strlen($buf) != 24) return false; $tmp = unpack('H32id/Vlen/H8unused', $buf); return $tmp; } } // mp3 class (if not IDv2 then select IDv1) class _Mp3Exif extends _AudioExif { var $head1; var $genres = array('Blues','Classic Rock','Country','Dance','Disco','Funk','Grunge','Hip-Hop','Jazz','Metal','New Age','Oldies','Other','Pop','R&B','Rap','Reggae','Rock','Techno','Industrial','Alternative','Ska','Death Metal','Pranks','Soundtrack','Euro-Techno','Ambient','Trip-Hop','Vocal','Jazz+Funk','Fusion','Trance','Classical','Instrumental','Acid','House','Game','Sound Clip','Gospel','Noise','AlternRock','Bass','Soul','Punk','Space','Meditative','Instrumental Pop','Instrumental Rock','Ethnic','Gothic','Darkwave','Techno-Industrial','Electronic','Pop-Folk','Eurodance','Dream','Southern Rock','Comedy','Cult','Gangsta','Top 40','Christian Rap','Pop/Funk','Jungle','Native American','Cabaret','New Wave','Psychadelic','Rave','Showtunes','Trailer','Lo-Fi','Tribal','Acid Punk','Acid Jazz','Polka','Retro','Musical','Rock & Roll','Hard Rock','Unknown'); // MP3 always return true function check_size($file) { return true; } // get info function get_info($file) { if (!$this->_file_init($file)) return false; $ret = false; if ($this->_init_header()) { $ret = ($this->head ? $this->_get_v2_info() : $this->_get_v1_info()); $ret['meta'] = $this->_get_meta_info(); } $this->_file_deinit(); return $ret; } // set info function set_info($file, $pa) { if (!$this->_file_init($file, true)) return false; if ($this->_init_header()) { // always save v1 info $this->_set_v1_info($pa); // set v2 first if need $this->_set_v2_info($pa); } $this->_file_deinit(); return true; } // get the header information[v1+v2], call after file_init function _init_header() { $this->head1 = false; $this->head = false; // try to get ID3v1 first fseek($this->fd, -128, SEEK_END); $buf = fread($this->fd, 128); if (strlen($buf) == 128 && substr($buf, 0, 3) == 'TAG') { $tmp = unpack('a3id/a30Title/a30Artist/a30AlbumTitle/a4Year/a28Description/CReserved/CTrack/CGenre', $buf); $this->head1 = $tmp; } // try to get ID3v2 fseek($this->fd, 0, SEEK_SET); $buf = fread($this->fd, 10); if (strlen($buf) == 10 && substr($buf, 0, 3) == 'ID3') { $tmp = unpack('a3id/Cver/Crev/Cflag/C4size', $buf); $tmp['size'] = ($tmp['size1']<<21)|($tmp['size2']<<14)|($tmp['size3']<<7)|$tmp['size4']; unset($tmp['size1'], $tmp['size2'], $tmp['size3'], $tmp['size4']); $this->head = $tmp; $this->head_buf = fread($this->fd, $tmp['size']); } return ($this->head1 || $this->head); } // get v1 info function _get_v1_info() { $ret = array(); $tmpa = array('Title', 'Artist', 'Copyright', 'Description', 'Year', 'AlbumTitle'); foreach ($tmpa as $tmp) { $ret[$tmp] = $this->head1[$tmp]; if ($pos = strpos($ret[$tmp], " ")) $ret[$tmp] = substr($ret[$tmp], 0, $pos); } // count the Genre, [Track] if ($this->head1['Reserved'] == 0) $ret['Track'] = $this->head1['Track']; else $ret['Description'] .= chr($ret['Reserved']) . chr($ret['Track']); // Genre_idx $g = $this->head1['Genre']; if (!isset($this->genres[$g])) $ret['Genre'] = 'Unknown'; else $ret['Genre'] = $this->genres[$g]; // return the value $ret['ID3v1'] = 'yes'; return $ret; } // get v2 info function _get_v2_info() { $ret = array(); $items = array( 'TCOP'=>'Copyright', 'TPE1'=>'Artist', 'TIT2'=>'Title', 'TRCK'=> 'Track', 'TCON'=>'Genre', 'COMM'=>'Description', 'TYER'=>'Year', 'TALB'=>'AlbumTitle'); while (true) { $buf = $this->_read_head_buf(10); if (strlen($buf) != 10) break; $tmp = unpack('a4fid/Nsize/nflag', $buf); if ($tmp['size'] == 0) break; $tmp['dat'] = $this->_read_head_buf($tmp['size']); // 0x6000 (11000000 00000000) if ($tmp['flag'] & 0x6000) continue; // mapping the data if ($k = $items[$tmp['fid']]) { // If first char is " ", just skip if (substr($tmp['dat'], 0, 1) == " ") $tmp['dat'] = substr($tmp['dat'], 1); $ret[$k] = $tmp['dat']; } } // reset the genre if ($g = $ret['Genre']) { if (substr($g,0,1) == '(' && substr($g,-1,1) == ')') $g = substr($g, 1, -1); if (is_numeric($g)) { $g = intval($g); $ret['Genre'] = (isset($this->genres[$g]) ? $this->genres[$g] : 'Unknown'); } } $ret['ID3v1'] = 'no'; return $ret; } // get meta info of MP3 function _get_meta_info() { // seek to the lead buf: 0xff $off = 0; if ($this->head) $off = $this->head['size'] + 10; fseek($this->fd, $off, SEEK_SET); while (!feof($this->fd)) { $skip = ord(fread($this->fd, 1)); if ($skip == 0xff) break; } if ($skip != 0xff) return false; $buf = fread($this->fd, 3); if (strlen($buf) != 3) return false; $tmp = unpack('C3', $buf); if (($tmp[1] & 0xf0) != 0xf0) return false; // get the meta info $meta = array(); // get mpeg version $meta['mpeg'] = ($tmp[1] & 0x08 ? 1 : 2); $meta['layer'] = ($tmp[1] & 0x04) ? (($tmp[1] & 0x02) ? 1 : 2) : (($tmp[1] & 0x02) ? 3 : 0); $meta['epro'] = ($tmp[1] & 0x01) ? 'no' : 'yes'; // bit rates $bit_rates = array( 1 => array( 1 => array(0,32,64,96,128,160,192,224,256,288,320,352,384,416,448,0), 2 => array(0,32,48,56,64,80,96,112,128,160,192,224,256,320,384,0), 3 => array(0,32,40,48,56,64,80,96,112,128,160,192,224,256,320,0) ), 2 => array( 1 => array(0,32,48,56,64,80,96,112,128,144,160,176,192,224,256,0), 2 => array(0,8,16,24,32,40,48,56,64,80,96,112,128,144,160,0), 3 => array(0,8,16,24,32,40,48,56,64,80,96,112,128,144,160,0) ) ); $i = $meta['mpeg']; $j = $meta['layer']; $k = ($tmp[2]>>4); $meta['bitrate'] = $bit_rates[$i][$j][$k]; // sample rates <采樣率> $sam_rates = array(1=>array(44100,48000,32000,0), 2=>array(22050,24000,16000,0)); $meta['samrate'] = $sam_rates[$i][$k]; $meta["padding"] = ($tmp[2] & 0x02) ? 'on' : 'off'; $meta["private"] = ($tmp[2] & 0x01) ? 'on' : 'off'; // mode & mode_ext $k = ($tmp[3]>>6); $channel_modes = array('stereo', 'joint stereo', 'dual channel', 'single channel'); $meta['mode'] = $channel_modes[$k]; $k = (($tmp[3]>>4) & 0x03); $extend_modes = array('MPG_MD_LR_LR', 'MPG_MD_LR_I', 'MPG_MD_MS_LR', 'MPG_MD_MS_I'); $meta['ext_mode'] = $extend_modes[$k]; $meta['copyright'] = ($tmp[3] & 0x08) ? 'yes' : 'no'; $meta['original'] = ($tmp[3] & 0x04) ? 'yes' : 'no'; $emphasis = array('none', '50/15 microsecs', 'rreserved', 'CCITT J 17'); $k = ($tmp[3] & 0x03); $meta['emphasis'] = $emphasis[$k]; return $meta; } // set v1 info function _set_v1_info($pa) { // ID3v1 (simpled) $off = -128; if (!($tmp = $this->head1)) { $off = 0; $tmp['id'] = 'TAG'; $tmp['Title'] = $tmp['Artist'] = $tmp['AlbumTitle'] = $tmp['Year'] = $tmp['Description'] = ''; $tmp['Reserved'] = $tmp['Track'] = $tmp['Genre'] = 0; } // basic items $items = array('Title', 'Artist', 'Copyright', 'Description', 'Year', 'AlbumTitle'); foreach ($items as $k) { if (isset($pa[$k])) $tmp[$k] = $pa[$k]; } // genre index if (isset($pa['Genre'])) { $g = 0; foreach ($this->genres as $gtmp) { if (!strcasecmp($gtmp, $pa['Genre'])) break; $g++; } $tmp['Genre'] = $g; } if (isset($pa['Track'])) $tmp['Track'] = intval($pa['Track']); // pack the data $buf = pack('a3a30a30a30a4a28CCC', $tmp['id'], $tmp['Title'], $tmp['Artist'], $tmp['AlbumTitle'], $tmp['Year'], $tmp['Description'], 0, $tmp['Track'], $tmp['Genre']); flock($this->fd, LOCK_EX); fseek($this->fd, $off, SEEK_END); fwrite($this->fd, $buf, 128); flock($this->fd, LOCK_UN); } // set v2 info function _set_v2_info($pa) { if (!$this->head) { // insert ID3 return; // 沒有就算了 /** $tmp = array('id'=>'ID3','ver'=>3,'rev'=>0,'flag'=>0); $tmp['size'] = -10; // +10 => 0 $this->head = $tmp; $this->head_buf = ''; $this->head_off = 0; **/ } $items = array( 'TCOP'=>'Copyright', 'TPE1'=>'Artist', 'TIT2'=>'Title', 'TRAC'=>'Track', 'TCON'=>'Genre', 'COMM'=>'Description', 'TYER'=>'Year', 'TALB'=>'AlbumTitle'); $head_body = ''; while (true) { $buf = $this->_read_head_buf(10); if (strlen($buf) != 10) break; $tmp = unpack('a4fid/Nsize/nflag', $buf); if ($tmp['size'] == 0) break; $data = $this->_read_head_buf($tmp['size']); if (($k = $items[$tmp['fid']]) && isset($pa[$k])) { // the data should prefix by " " [replace] $data = " " . $pa[$k]; unset($pa[$k]); } $head_body .= pack('a4Nn', $tmp['fid'], strlen($data), $tmp['flag']) . $data; } // reverse the items & set the new tags $items = array_flip($items); foreach ($pa as $k => $v) { if ($fid = $items[$k]) { $head_body .= pack('a4Nn', $fid, strlen($v) + 1, 0) . " " . $v; } } // new length $new_len = strlen($head_body) + 10; $old_len = $this->head['size'] + 10; if ($new_len < $old_len) { $head_body .= str_repeat(" ", $old_len - $new_len); $new_len = $old_len; } // count the size1,2,3,4, no include the header // 較為變態的算法... :p (28bytes integer) $size = array(); $nlen = $new_len - 10; for ($i = 4; $i > 0; $i--) { $size[$i] = ($nlen & 0x7f); $nlen >>= 7; } $tmp = $this->head; //echo "old_len : $old_len new_len: $new_lenn"; $head_buf = pack('a3CCCCCCC', $tmp['id'], $tmp['ver'], $tmp['rev'], $tmp['flag'], $size[1], $size[2], $size[3], $size[4]); $head_buf .= $head_body; $this->_file_save($head_buf, $old_len, $new_len); }以上所述就是本文的全部內容了，希望大家能夠喜歡。
