PHP获取音频文件的相关信息

项目需求：现在有一个音频文件上传的功能，在上传后PHP需要获取这个音频文件的相关信息，例如：时长等，由于这个文件是放在买的空间上的，没有像ffmpeg这样的扩展来处理，那么PHP能不能获取到这些信息？

下面是之前在项目中用到的一个用PHP进行音频文件头部信息的读取与写入操作的实现，主要针对 WMA 和 MP3 两种格式，供参考。

<?php// AudioExif.class.php// 用PHP进行音频文件头部信息的读取与写入// 目前只支持 WMA 和 MP3 两种格式, 只支持常用的几个头部信息//// 写入信息支持: Title(名称), Artist(艺术家), Copyright(版权), Description (描述)// Year(年代), Genre (流派), AlbumTitle (专辑标题)// 其中 mp3 和 wma 略有不同, 具体返回的信息还可能更多, 但只有以上信息可以被写入// mp3 还支持 Track (曲目编号写入)// 对于 MP3 文件支持 ID3v1也支持ID3v2, 读取时优先 v2, 写入时总是会写入v1, 必要时写入v2//// 用法说明: (由于 wma 使用 Unicode 存取, 故还需要 mb_convert_encoding() 扩展// 返回数据及写入数据均为 ANSI 编码, 即存什么就显示什么 (中文_GB2312)//// require ('AudioExif.class.php');// $AE = new AudioExif;// $file = '/path/to/test.mp3';//// 1. 检查文件是否完整 (only for wma, mp3始终返回 true)//// $AE->CheckSize($file);//// 2. 读取信息, 返回值由信息组成的数组, 键名解释参见上方//// print_r($AE->GetInfo($file));//// 3. 写入信息, 第二参数是一个哈希数组, 键->值, 支持的参见上方的, mp3也支持 Track// 要求第一参数的文件路径可由本程序写入// $pa = array('Title' => '新标题', 'AlbumTitle' => '新的专辑名称');// $AE->SetInfo($file, $pa);//// 其它: 该插件花了不少时间搜集查找 wma及mp3 的文件格式说明文档与网页, 希望对大家有用.// 其实网上已经有不少类似的程序, 但对 wma 实在太少了, 只能在 win 平台下通过 M$ 的// API 来操作, 而 MP3 也很少有可以在 unix/linux 命令行操作的, 所以特意写了这个模块//// 如果发现 bug 或提交 patch, 或加以改进使它更加健壮, 请告诉我.// (关于 ID3和Wma的文件格式及结构 在网上应该都可以找到参考资料)//if (!extension_loaded('mbstring')){trigger_error('PHP Extension module `mbstring` is required for AudioExif', E_USER_WARNING);return true;}// the Main Classclass AudioExif{// public varsvar $_wma = false;var $_mp3 = false;// Constructfunction AudioExif() {// nothing to do}// check the filesizefunction CheckSize($file) {$handler = &$this->_get_handler($file);if (!$handler) return false;return $handler->check_size($file);}// get the infomationsfunction GetInfo($file) {$handler = &$this->_get_handler($file);if (!$handler) return false;return $handler->get_info($file);}// write the infomationsfunction SetInfo($file, $pa) {if (!is_writable($file)) {trigger_error('AudioExif: file `' . $file . '` can not been overwritten', E_USER_WARNING);return false;}$handler = &$this->_get_handler($file);if (!$handler) return false;return $handler->set_info($file, $pa);}// private methodsfunction &_get_handler($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{ // unknowntrigger_error('AudioExif not supported `' . $ext . '` file.', E_USER_WARNING);}return $ret;}}// DBCS => gb2312function dbcs_gbk($str){// strip the last "/0/0"$str = substr($str, 0, -2);return mb_convert_encoding($str, 'GBK', 'UCS-2LE');}// gb2312 => DBCSfunction gbk_dbcs($str){$str = mb_convert_encoding($str, 'UCS-2LE', 'GBK');$str .= "/0/0";return $str;}// file exifclass _AudioExif{var $fd;var $head;var $head_off;var $head_buf;// init the file handlerfunction _file_init($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 pointerfunction _read_head_buf($len){if ($len <= 0) return NULL;$buf = substr($this->head_buf, $this->head_off, $len);$this->head_off += strlen($buf);return $buf;}// read one short valuefunction _read_head_short(){$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 headfunction _file_save($head, $olen, $nlen = 0){if ($nlen == 0) $nlen = strlen($head);if ($nlen == $olen){// shorterflock($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 = $stat['size'];// buf required (4096?) 应该不会 nlen - olen > 4096 吧$woff = 0;$roff = $olen;// read first bufferflock($this->fd, LOCK_EX);fseek($this->fd, $roff, SEEK_SET);$buf = fread($this->fd, 4096);// seek to startfseek($this->fd, $woff, SEEK_SET);fwrite($this->fd, $head, $nlen);$woff += $nlen;// seek to woff & write the datado{$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 filefunction _file_deinit(){if ($this->fd){fclose($this->fd);$this->fd = false;}}}// wma classclass _WmaExif extends _AudioExif{var $items1 = array('Title', 'Artist', 'Copyright', 'Description', 'Reserved');var $items2 = array('Year', 'Genre', 'AlbumTitle');// check file size (length) maybe invalid filefunction check_size($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, $pa){// check the pasettype($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 + 24for ($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($data));}// left lengthif ($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("/0", $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 infofunction 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 = $this->head['num']; // num of head_framewhile (($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 onlyif ($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 $genres = array('Blues','Classic Rock','Country','Dance','Disco','Funk','Grunge','Hip-Hop','Jazz','Metal','New Age','Oldies','Other','Pop','R&B','Rap','Reggae','Rock','Techno','Industrial','Alternative','Ska','Death Metal','Pranks','Soundtrack','Euro-Techno','Ambient','Trip-Hop','Vocal','Jazz+Funk','Fusion','Trance','Classical','Instrumental','Acid','House','Game','Sound Clip','Gospel','Noise','AlternRock','Bass','Soul','Punk','Space','Meditative','Instrumental Pop','Instrumental Rock','Ethnic','Gothic','Darkwave','Techno-Industrial','Electronic','Pop-Folk','Eurodance','Dream','Southern Rock','Comedy','Cult','Gangsta','Top 40','Christian Rap','Pop/Funk','Jungle','Native American','Cabaret','New Wave','Psychadelic','Rave','Showtunes','Trailer','Lo-Fi','Tribal','Acid Punk','Acid Jazz','Polka','Retro','Musical','Rock & Roll','Hard Rock','Unknown');// MP3 always return truefunction check_size($file){return true;}// get infofunction 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 $ret;}// set infofunction set_info($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);}$this->_file_deinit();return true;}// get the header information[v1+v2], call after file_initfunction _init_header(){$this->head1 = false;$this->head = false;// try to get ID3v1 firstfseek($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 = $tmp;}// try to get ID3v2fseek($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 || $this->head);}// get v1 infofunction _get_v1_info(){$ret = array();$tmpa = array('Title', 'Artist', 'Copyright', 'Description', 'Year', 'AlbumTitle');foreach ($tmpa as $tmp){$ret[$tmp] = $this->head1[$tmp];if ($pos = strpos($ret[$tmp], "/0"))$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 $ret;}// get v2 infofunction _get_v2_info(){$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 ($tmp['flag'] & 0x6000) continue;// mapping the dataif ($k = $items[$tmp['fid']]){ // If first char is "/0", just skipif (substr($tmp['dat'], 0, 1) == "/0") $tmp['dat'] = substr($tmp['dat'], 1);$ret[$k] = $tmp['dat'];}}// reset the genreif ($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 $ret;}// get meta info of MP3function _get_meta_info(){// seek to the lead buf: 0xff$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 <采样率>$sam_rates = array(1=>array(44100,48000,32000,0), 2=>array(22050,24000,16000,0));$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 $meta;}// set v1 infofunction _set_v1_info($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 indexif (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 infofunction _set_v2_info($pa){if (!$this->head){ // insert ID3return; // 没有就算了/**$tmp = array('id'=>'ID3','ver'=>3,'rev'=>0,'flag'=>0);$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 "/0" [replace]$data = "/0" . $pa[$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) . "/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("/0", $old_len - $new_len);$new_len = $old_len;}// count the size1,2,3,4, no include the header// 较为变态的算法... :p (28bytes integer)$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: $new_len/n";$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);}