getid3.lib.php

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<?php
//  available at http://getid3.sourceforge.net                 //
//            or http://www.getid3.org                         //
//          also https://github.com/JamesHeinrich/getID3       //
//                                                             //
// getid3.lib.php - part of getID3()                           //
// See readme.txt for more details                             //
//                                                            ///
 
 
class getid3_lib
{
 
        public static function PrintHexBytes($string, $hex=true, $spaces=true, $htmlencoding='UTF-8') {
                $returnstring = '';
                for ($i = 0; $i < strlen($string); $i++) {
                        if ($hex) {
                                $returnstring .= str_pad(dechex(ord($string{$i})), 2, '0', STR_PAD_LEFT);
                        } else {
                                $returnstring .= ' '.(preg_match("#[\x20-\x7E]#", $string{$i}) ? $string{$i} : '¤');
                        }
                        if ($spaces) {
                                $returnstring .= ' ';
                        }
                }
                if (!empty($htmlencoding)) {
                        if ($htmlencoding === true) {
                                $htmlencoding = 'UTF-8'; // prior to getID3 v1.9.0 the function's 4th parameter was boolean
                        }
                        $returnstring = htmlentities($returnstring, ENT_QUOTES, $htmlencoding);
                }
                return $returnstring;
        }
 
        public static function trunc($floatnumber) {
                // truncates a floating-point number at the decimal point
                // returns int (if possible, otherwise float)
                if ($floatnumber >= 1) {
                        $truncatednumber = floor($floatnumber);
                } elseif ($floatnumber <= -1) {
                        $truncatednumber = ceil($floatnumber);
                } else {
                        $truncatednumber = 0;
                }
                if (self::intValueSupported($truncatednumber)) {
                        $truncatednumber = (int) $truncatednumber;
                }
                return $truncatednumber;
        }
 
 
        public static function safe_inc(&$variable, $increment=1) {
                if (isset($variable)) {
                        $variable += $increment;
                } else {
                        $variable = $increment;
                }
                return true;
        }
 
        public static function CastAsInt($floatnum) {
                // convert to float if not already
                $floatnum = (float) $floatnum;
 
                // convert a float to type int, only if possible
                if (self::trunc($floatnum) == $floatnum) {
                        // it's not floating point
                        if (self::intValueSupported($floatnum)) {
                                // it's within int range
                                $floatnum = (int) $floatnum;
                        }
                }
                return $floatnum;
        }
 
        public static function intValueSupported($num) {
                // check if integers are 64-bit
                static $hasINT64 = null;
                if ($hasINT64 === null) { // 10x faster than is_null()
                        $hasINT64 = is_int(pow(2, 31)); // 32-bit int are limited to (2^31)-1
                        if (!$hasINT64 && !defined('PHP_INT_MIN')) {
                                define('PHP_INT_MIN', ~PHP_INT_MAX);
                        }
                }
                // if integers are 64-bit - no other check required
                if ($hasINT64 || (($num <= PHP_INT_MAX) && ($num >= PHP_INT_MIN))) {
                        return true;
                }
                return false;
        }
 
        public static function DecimalizeFraction($fraction) {
                list($numerator, $denominator) = explode('/', $fraction);
                return $numerator / ($denominator ? $denominator : 1);
        }
 
 
        public static function DecimalBinary2Float($binarynumerator) {
                $numerator   = self::Bin2Dec($binarynumerator);
                $denominator = self::Bin2Dec('1'.str_repeat('0', strlen($binarynumerator)));
                return ($numerator / $denominator);
        }
 
 
        public static function NormalizeBinaryPoint($binarypointnumber, $maxbits=52) {
                // http://www.scri.fsu.edu/~jac/MAD3401/Backgrnd/binary.html
                if (strpos($binarypointnumber, '.') === false) {
                        $binarypointnumber = '0.'.$binarypointnumber;
                } elseif ($binarypointnumber{0} == '.') {
                        $binarypointnumber = '0'.$binarypointnumber;
                }
                $exponent = 0;
                while (($binarypointnumber{0} != '1') || (substr($binarypointnumber, 1, 1) != '.')) {
                        if (substr($binarypointnumber, 1, 1) == '.') {
                                $exponent--;
                                $binarypointnumber = substr($binarypointnumber, 2, 1).'.'.substr($binarypointnumber, 3);
                        } else {
                                $pointpos = strpos($binarypointnumber, '.');
                                $exponent += ($pointpos - 1);
                                $binarypointnumber = str_replace('.', '', $binarypointnumber);
                                $binarypointnumber = $binarypointnumber{0}.'.'.substr($binarypointnumber, 1);
                        }
                }
                $binarypointnumber = str_pad(substr($binarypointnumber, 0, $maxbits + 2), $maxbits + 2, '0', STR_PAD_RIGHT);
                return array('normalized'=>$binarypointnumber, 'exponent'=>(int) $exponent);
        }
 
 
        public static function Float2BinaryDecimal($floatvalue) {
                // http://www.scri.fsu.edu/~jac/MAD3401/Backgrnd/binary.html
                $maxbits = 128; // to how many bits of precision should the calculations be taken?
                $intpart   = self::trunc($floatvalue);
                $floatpart = abs($floatvalue - $intpart);
                $pointbitstring = '';
                while (($floatpart != 0) && (strlen($pointbitstring) < $maxbits)) {
                        $floatpart *= 2;
                        $pointbitstring .= (string) self::trunc($floatpart);
                        $floatpart -= self::trunc($floatpart);
                }
                $binarypointnumber = decbin($intpart).'.'.$pointbitstring;
                return $binarypointnumber;
        }
 
 
        public static function Float2String($floatvalue, $bits) {
                // http://www.scri.fsu.edu/~jac/MAD3401/Backgrnd/ieee-expl.html
                switch ($bits) {
                        case 32:
                                $exponentbits = 8;
                                $fractionbits = 23;
                                break;
 
                        case 64:
                                $exponentbits = 11;
                                $fractionbits = 52;
                                break;
 
                        default:
                                return false;
                                break;
                }
                if ($floatvalue >= 0) {
                        $signbit = '0';
                } else {
                        $signbit = '1';
                }
                $normalizedbinary  = self::NormalizeBinaryPoint(self::Float2BinaryDecimal($floatvalue), $fractionbits);
                $biasedexponent    = pow(2, $exponentbits - 1) - 1 + $normalizedbinary['exponent']; // (127 or 1023) +/- exponent
                $exponentbitstring = str_pad(decbin($biasedexponent), $exponentbits, '0', STR_PAD_LEFT);
                $fractionbitstring = str_pad(substr($normalizedbinary['normalized'], 2), $fractionbits, '0', STR_PAD_RIGHT);
 
                return self::BigEndian2String(self::Bin2Dec($signbit.$exponentbitstring.$fractionbitstring), $bits % 8, false);
        }
 
 
        public static function LittleEndian2Float($byteword) {
                return self::BigEndian2Float(strrev($byteword));
        }
 
 
        public static function BigEndian2Float($byteword) {
                // ANSI/IEEE Standard 754-1985, Standard for Binary Floating Point Arithmetic
                // http://www.psc.edu/general/software/packages/ieee/ieee.html
                // http://www.scri.fsu.edu/~jac/MAD3401/Backgrnd/ieee.html
 
                $bitword = self::BigEndian2Bin($byteword);
                if (!$bitword) {
                        return 0;
                }
                $signbit = $bitword{0};
 
                switch (strlen($byteword) * 8) {
                        case 32:
                                $exponentbits = 8;
                                $fractionbits = 23;
                                break;
 
                        case 64:
                                $exponentbits = 11;
                                $fractionbits = 52;
                                break;
 
                        case 80:
                                // 80-bit Apple SANE format
                                // http://www.mactech.com/articles/mactech/Vol.06/06.01/SANENormalized/
                                $exponentstring = substr($bitword, 1, 15);
                                $isnormalized = intval($bitword{16});
                                $fractionstring = substr($bitword, 17, 63);
                                $exponent = pow(2, self::Bin2Dec($exponentstring) - 16383);
                                $fraction = $isnormalized + self::DecimalBinary2Float($fractionstring);
                                $floatvalue = $exponent * $fraction;
                                if ($signbit == '1') {
                                        $floatvalue *= -1;
                                }
                                return $floatvalue;
                                break;
 
                        default:
                                return false;
                                break;
                }
                $exponentstring = substr($bitword, 1, $exponentbits);
                $fractionstring = substr($bitword, $exponentbits + 1, $fractionbits);
                $exponent = self::Bin2Dec($exponentstring);
                $fraction = self::Bin2Dec($fractionstring);
 
                if (($exponent == (pow(2, $exponentbits) - 1)) && ($fraction != 0)) {
                        // Not a Number
                        $floatvalue = false;
                } elseif (($exponent == (pow(2, $exponentbits) - 1)) && ($fraction == 0)) {
                        if ($signbit == '1') {
                                $floatvalue = '-infinity';
                        } else {
                                $floatvalue = '+infinity';
                        }
                } elseif (($exponent == 0) && ($fraction == 0)) {
                        if ($signbit == '1') {
                                $floatvalue = -0;
                        } else {
                                $floatvalue = 0;
                        }
                        $floatvalue = ($signbit ? 0 : -0);
                } elseif (($exponent == 0) && ($fraction != 0)) {
                        // These are 'unnormalized' values
                        $floatvalue = pow(2, (-1 * (pow(2, $exponentbits - 1) - 2))) * self::DecimalBinary2Float($fractionstring);
                        if ($signbit == '1') {
                                $floatvalue *= -1;
                        }
                } elseif ($exponent != 0) {
                        $floatvalue = pow(2, ($exponent - (pow(2, $exponentbits - 1) - 1))) * (1 + self::DecimalBinary2Float($fractionstring));
                        if ($signbit == '1') {
                                $floatvalue *= -1;
                        }
                }
                return (float) $floatvalue;
        }
 
 
        public static function BigEndian2Int($byteword, $synchsafe=false, $signed=false) {
                $intvalue = 0;
                $bytewordlen = strlen($byteword);
                if ($bytewordlen == 0) {
                        return false;
                }
                for ($i = 0; $i < $bytewordlen; $i++) {
                        if ($synchsafe) { // disregard MSB, effectively 7-bit bytes
                                //$intvalue = $intvalue | (ord($byteword{$i}) & 0x7F) << (($bytewordlen - 1 - $i) * 7); // faster, but runs into problems past 2^31 on 32-bit systems
                                $intvalue += (ord($byteword{$i}) & 0x7F) * pow(2, ($bytewordlen - 1 - $i) * 7);
                        } else {
                                $intvalue += ord($byteword{$i}) * pow(256, ($bytewordlen - 1 - $i));
                        }
                }
                if ($signed && !$synchsafe) {
                        // synchsafe ints are not allowed to be signed
                        if ($bytewordlen <= PHP_INT_SIZE) {
                                $signMaskBit = 0x80 << (8 * ($bytewordlen - 1));
                                if ($intvalue & $signMaskBit) {
                                        $intvalue = 0 - ($intvalue & ($signMaskBit - 1));
                                }
                        } else {
                                throw new Exception('ERROR: Cannot have signed integers larger than '.(8 * PHP_INT_SIZE).'-bits ('.strlen($byteword).') in self::BigEndian2Int()');
                        }
                }
                return self::CastAsInt($intvalue);
        }
 
 
        public static function LittleEndian2Int($byteword, $signed=false) {
                return self::BigEndian2Int(strrev($byteword), false, $signed);
        }
 
 
        public static function BigEndian2Bin($byteword) {
                $binvalue = '';
                $bytewordlen = strlen($byteword);
                for ($i = 0; $i < $bytewordlen; $i++) {
                        $binvalue .= str_pad(decbin(ord($byteword{$i})), 8, '0', STR_PAD_LEFT);
                }
                return $binvalue;
        }
 
 
        public static function BigEndian2String($number, $minbytes=1, $synchsafe=false, $signed=false) {
                if ($number < 0) {
                        throw new Exception('ERROR: self::BigEndian2String() does not support negative numbers');
                }
                $maskbyte = (($synchsafe || $signed) ? 0x7F : 0xFF);
                $intstring = '';
                if ($signed) {
                        if ($minbytes > PHP_INT_SIZE) {
                                throw new Exception('ERROR: Cannot have signed integers larger than '.(8 * PHP_INT_SIZE).'-bits in self::BigEndian2String()');
                        }
                        $number = $number & (0x80 << (8 * ($minbytes - 1)));
                }
                while ($number != 0) {
                        $quotient = ($number / ($maskbyte + 1));
                        $intstring = chr(ceil(($quotient - floor($quotient)) * $maskbyte)).$intstring;
                        $number = floor($quotient);
                }
                return str_pad($intstring, $minbytes, "\x00", STR_PAD_LEFT);
        }
 
 
        public static function Dec2Bin($number) {
                while ($number >= 256) {
                        $bytes[] = (($number / 256) - (floor($number / 256))) * 256;
                        $number = floor($number / 256);
                }
                $bytes[] = $number;
                $binstring = '';
                for ($i = 0; $i < count($bytes); $i++) {
                        $binstring = (($i == count($bytes) - 1) ? decbin($bytes[$i]) : str_pad(decbin($bytes[$i]), 8, '0', STR_PAD_LEFT)).$binstring;
                }
                return $binstring;
        }
 
 
        public static function Bin2Dec($binstring, $signed=false) {
                $signmult = 1;
                if ($signed) {
                        if ($binstring{0} == '1') {
                                $signmult = -1;
                        }
                        $binstring = substr($binstring, 1);
                }
                $decvalue = 0;
                for ($i = 0; $i < strlen($binstring); $i++) {
                        $decvalue += ((int) substr($binstring, strlen($binstring) - $i - 1, 1)) * pow(2, $i);
                }
                return self::CastAsInt($decvalue * $signmult);
        }
 
 
        public static function Bin2String($binstring) {
                // return 'hi' for input of '0110100001101001'
                $string = '';
                $binstringreversed = strrev($binstring);
                for ($i = 0; $i < strlen($binstringreversed); $i += 8) {
                        $string = chr(self::Bin2Dec(strrev(substr($binstringreversed, $i, 8)))).$string;
                }
                return $string;
        }
 
 
        public static function LittleEndian2String($number, $minbytes=1, $synchsafe=false) {
                $intstring = '';
                while ($number > 0) {
                        if ($synchsafe) {
                                $intstring = $intstring.chr($number & 127);
                                $number >>= 7;
                        } else {
                                $intstring = $intstring.chr($number & 255);
                                $number >>= 8;
                        }
                }
                return str_pad($intstring, $minbytes, "\x00", STR_PAD_RIGHT);
        }
 
 
        public static function array_merge_clobber($array1, $array2) {
                // written by kcØhireability*com
                // taken from http://www.php.net/manual/en/function.array-merge-recursive.php
                if (!is_array($array1) || !is_array($array2)) {
                        return false;
                }
                $newarray = $array1;
                foreach ($array2 as $key => $val) {
                        if (is_array($val) && isset($newarray[$key]) && is_array($newarray[$key])) {
                                $newarray[$key] = self::array_merge_clobber($newarray[$key], $val);
                        } else {
                                $newarray[$key] = $val;
                        }
                }
                return $newarray;
        }
 
 
        public static function array_merge_noclobber($array1, $array2) {
                if (!is_array($array1) || !is_array($array2)) {
                        return false;
                }
                $newarray = $array1;
                foreach ($array2 as $key => $val) {
                        if (is_array($val) && isset($newarray[$key]) && is_array($newarray[$key])) {
                                $newarray[$key] = self::array_merge_noclobber($newarray[$key], $val);
                        } elseif (!isset($newarray[$key])) {
                                $newarray[$key] = $val;
                        }
                }
                return $newarray;
        }
 
        public static function flipped_array_merge_noclobber($array1, $array2) {
                if (!is_array($array1) || !is_array($array2)) {
                        return false;
                }
                # naturally, this only works non-recursively
                $newarray = array_flip($array1);
                foreach (array_flip($array2) as $key => $val) {
                        if (!isset($newarray[$key])) {
                                $newarray[$key] = count($newarray);
                        }
                }
                return array_flip($newarray);
        }
 
 
        public static function ksort_recursive(&$theArray) {
                ksort($theArray);
                foreach ($theArray as $key => $value) {
                        if (is_array($value)) {
                                self::ksort_recursive($theArray[$key]);
                        }
                }
                return true;
        }
 
        public static function fileextension($filename, $numextensions=1) {
                if (strstr($filename, '.')) {
                        $reversedfilename = strrev($filename);
                        $offset = 0;
                        for ($i = 0; $i < $numextensions; $i++) {
                                $offset = strpos($reversedfilename, '.', $offset + 1);
                                if ($offset === false) {
                                        return '';
                                }
                        }
                        return strrev(substr($reversedfilename, 0, $offset));
                }
                return '';
        }
 
 
        public static function PlaytimeString($seconds) {
                $sign = (($seconds < 0) ? '-' : '');
                $seconds = round(abs($seconds));
                $H = (int) floor( $seconds                            / 3600);
                $M = (int) floor(($seconds - (3600 * $H)            ) /   60);
                $S = (int) round( $seconds - (3600 * $H) - (60 * $M)        );
                return $sign.($H ? $H.':' : '').($H ? str_pad($M, 2, '0', STR_PAD_LEFT) : intval($M)).':'.str_pad($S, 2, 0, STR_PAD_LEFT);
        }
 
 
        public static function DateMac2Unix($macdate) {
                // Macintosh timestamp: seconds since 00:00h January 1, 1904
                // UNIX timestamp:      seconds since 00:00h January 1, 1970
                return self::CastAsInt($macdate - 2082844800);
        }
 
 
        public static function FixedPoint8_8($rawdata) {
                return self::BigEndian2Int(substr($rawdata, 0, 1)) + (float) (self::BigEndian2Int(substr($rawdata, 1, 1)) / pow(2, 8));
        }
 
 
        public static function FixedPoint16_16($rawdata) {
                return self::BigEndian2Int(substr($rawdata, 0, 2)) + (float) (self::BigEndian2Int(substr($rawdata, 2, 2)) / pow(2, 16));
        }
 
 
        public static function FixedPoint2_30($rawdata) {
                $binarystring = self::BigEndian2Bin($rawdata);
                return self::Bin2Dec(substr($binarystring, 0, 2)) + (float) (self::Bin2Dec(substr($binarystring, 2, 30)) / pow(2, 30));
        }
 
 
        public static function CreateDeepArray($ArrayPath, $Separator, $Value) {
                // assigns $Value to a nested array path:
                //   $foo = self::CreateDeepArray('/path/to/my', '/', 'file.txt')
                // is the same as:
                //   $foo = array('path'=>array('to'=>'array('my'=>array('file.txt'))));
                // or
                //   $foo['path']['to']['my'] = 'file.txt';
                $ArrayPath = ltrim($ArrayPath, $Separator);
                if (($pos = strpos($ArrayPath, $Separator)) !== false) {
                        $ReturnedArray[substr($ArrayPath, 0, $pos)] = self::CreateDeepArray(substr($ArrayPath, $pos + 1), $Separator, $Value);
                } else {
                        $ReturnedArray[$ArrayPath] = $Value;
                }
                return $ReturnedArray;
        }
 
        public static function array_max($arraydata, $returnkey=false) {
                $maxvalue = false;
                $maxkey = false;
                foreach ($arraydata as $key => $value) {
                        if (!is_array($value)) {
                                if ($value > $maxvalue) {
                                        $maxvalue = $value;
                                        $maxkey = $key;
                                }
                        }
                }
                return ($returnkey ? $maxkey : $maxvalue);
        }
 
        public static function array_min($arraydata, $returnkey=false) {
                $minvalue = false;
                $minkey = false;
                foreach ($arraydata as $key => $value) {
                        if (!is_array($value)) {
                                if ($value > $minvalue) {
                                        $minvalue = $value;
                                        $minkey = $key;
                                }
                        }
                }
                return ($returnkey ? $minkey : $minvalue);
        }
 
        public static function XML2array($XMLstring) {
                if (function_exists('simplexml_load_string') && function_exists('libxml_disable_entity_loader')) {
                        // http://websec.io/2012/08/27/Preventing-XEE-in-PHP.html
                        // https://core.trac.wordpress.org/changeset/29378
                        $loader = libxml_disable_entity_loader(true);
                        $XMLobject = simplexml_load_string($XMLstring, 'SimpleXMLElement', LIBXML_NOENT);
                        $return = self::SimpleXMLelement2array($XMLobject);
                        libxml_disable_entity_loader($loader);
                        return $return;
                }
                return false;
        }
 
        public static function SimpleXMLelement2array($XMLobject) {
                if (!is_object($XMLobject) && !is_array($XMLobject)) {
                        return $XMLobject;
                }
                $XMLarray = (is_object($XMLobject) ? get_object_vars($XMLobject) : $XMLobject);
                foreach ($XMLarray as $key => $value) {
                        $XMLarray[$key] = self::SimpleXMLelement2array($value);
                }
                return $XMLarray;
        }
 
 
        // Allan Hansen <ahØartemis*dk>
        // self::md5_data() - returns md5sum for a file from startuing position to absolute end position
        public static function hash_data($file, $offset, $end, $algorithm) {
                static $tempdir = '';
                if (!self::intValueSupported($end)) {
                        return false;
                }
                switch ($algorithm) {
                        case 'md5':
                                $hash_function = 'md5_file';
                                $unix_call     = 'md5sum';
                                $windows_call  = 'md5sum.exe';
                                $hash_length   = 32;
                                break;
 
                        case 'sha1':
                                $hash_function = 'sha1_file';
                                $unix_call     = 'sha1sum';
                                $windows_call  = 'sha1sum.exe';
                                $hash_length   = 40;
                                break;
 
                        default:
                                throw new Exception('Invalid algorithm ('.$algorithm.') in self::hash_data()');
                                break;
                }
                $size = $end - $offset;
                while (true) {
                        if (GETID3_OS_ISWINDOWS) {
 
                                // It seems that sha1sum.exe for Windows only works on physical files, does not accept piped data
                                // Fall back to create-temp-file method:
                                if ($algorithm == 'sha1') {
                                        break;
                                }
 
                                $RequiredFiles = array('cygwin1.dll', 'head.exe', 'tail.exe', $windows_call);
                                foreach ($RequiredFiles as $required_file) {
                                        if (!is_readable(GETID3_HELPERAPPSDIR.$required_file)) {
                                                // helper apps not available - fall back to old method
                                                break 2;
                                        }
                                }
                                $commandline  = GETID3_HELPERAPPSDIR.'head.exe -c '.$end.' '.escapeshellarg(str_replace('/', DIRECTORY_SEPARATOR, $file)).' | ';
                                $commandline .= GETID3_HELPERAPPSDIR.'tail.exe -c '.$size.' | ';
                                $commandline .= GETID3_HELPERAPPSDIR.$windows_call;
 
                        } else {
 
                                $commandline  = 'head -c'.$end.' '.escapeshellarg($file).' | ';
                                $commandline .= 'tail -c'.$size.' | ';
                                $commandline .= $unix_call;
 
                        }
                        if (preg_match('#(1|ON)#i', ini_get('safe_mode'))) {
                                //throw new Exception('PHP running in Safe Mode - backtick operator not available, using slower non-system-call '.$algorithm.' algorithm');
                                break;
                        }
                        return substr(`$commandline`, 0, $hash_length);
                }
 
                if (empty($tempdir)) {
                        // yes this is ugly, feel free to suggest a better way
                        require_once(dirname(__FILE__).'/getid3.php');
                        $getid3_temp = new getID3();
                        $tempdir = $getid3_temp->tempdir;
                        unset($getid3_temp);
                }
                // try to create a temporary file in the system temp directory - invalid dirname should force to system temp dir
                if (($data_filename = tempnam($tempdir, 'gI3')) === false) {
                        // can't find anywhere to create a temp file, just fail
                        return false;
                }
 
                // Init
                $result = false;
 
                // copy parts of file
                try {
                        self::CopyFileParts($file, $data_filename, $offset, $end - $offset);
                        $result = $hash_function($data_filename);
                } catch (Exception $e) {
                        throw new Exception('self::CopyFileParts() failed in getid_lib::hash_data(): '.$e->getMessage());
                }
                unlink($data_filename);
                return $result;
        }
 
        public static function CopyFileParts($filename_source, $filename_dest, $offset, $length) {
                if (!self::intValueSupported($offset + $length)) {
                        throw new Exception('cannot copy file portion, it extends beyond the '.round(PHP_INT_MAX / 1073741824).'GB limit');
                }
                if (is_readable($filename_source) && is_file($filename_source) && ($fp_src = fopen($filename_source, 'rb'))) {
                        if (($fp_dest = fopen($filename_dest, 'wb'))) {
                                if (fseek($fp_src, $offset) == 0) {
                                        $byteslefttowrite = $length;
                                        while (($byteslefttowrite > 0) && ($buffer = fread($fp_src, min($byteslefttowrite, getID3::FREAD_BUFFER_SIZE)))) {
                                                $byteswritten = fwrite($fp_dest, $buffer, $byteslefttowrite);
                                                $byteslefttowrite -= $byteswritten;
                                        }
                                        return true;
                                } else {
                                        throw new Exception('failed to seek to offset '.$offset.' in '.$filename_source);
                                }
                                fclose($fp_dest);
                        } else {
                                throw new Exception('failed to create file for writing '.$filename_dest);
                        }
                        fclose($fp_src);
                } else {
                        throw new Exception('failed to open file for reading '.$filename_source);
                }
                return false;
        }
 
        public static function iconv_fallback_int_utf8($charval) {
                if ($charval < 128) {
                        // 0bbbbbbb
                        $newcharstring = chr($charval);
                } elseif ($charval < 2048) {
                        // 110bbbbb 10bbbbbb
                        $newcharstring  = chr(($charval >>   6) | 0xC0);
                        $newcharstring .= chr(($charval & 0x3F) | 0x80);
                } elseif ($charval < 65536) {
                        // 1110bbbb 10bbbbbb 10bbbbbb
                        $newcharstring  = chr(($charval >>  12) | 0xE0);
                        $newcharstring .= chr(($charval >>   6) | 0xC0);
                        $newcharstring .= chr(($charval & 0x3F) | 0x80);
                } else {
                        // 11110bbb 10bbbbbb 10bbbbbb 10bbbbbb
                        $newcharstring  = chr(($charval >>  18) | 0xF0);
                        $newcharstring .= chr(($charval >>  12) | 0xC0);
                        $newcharstring .= chr(($charval >>   6) | 0xC0);
                        $newcharstring .= chr(($charval & 0x3F) | 0x80);
                }
                return $newcharstring;
        }
 
        // ISO-8859-1 => UTF-8
        public static function iconv_fallback_iso88591_utf8($string, $bom=false) {
                if (function_exists('utf8_encode')) {
                        return utf8_encode($string);
                }
                // utf8_encode() unavailable, use getID3()'s iconv_fallback() conversions (possibly PHP is compiled without XML support)
                $newcharstring = '';
                if ($bom) {
                        $newcharstring .= "\xEF\xBB\xBF";
                }
                for ($i = 0; $i < strlen($string); $i++) {
                        $charval = ord($string{$i});
                        $newcharstring .= self::iconv_fallback_int_utf8($charval);
                }
                return $newcharstring;
        }
 
        // ISO-8859-1 => UTF-16BE
        public static function iconv_fallback_iso88591_utf16be($string, $bom=false) {
                $newcharstring = '';
                if ($bom) {
                        $newcharstring .= "\xFE\xFF";
                }
                for ($i = 0; $i < strlen($string); $i++) {
                        $newcharstring .= "\x00".$string{$i};
                }
                return $newcharstring;
        }
 
        // ISO-8859-1 => UTF-16LE
        public static function iconv_fallback_iso88591_utf16le($string, $bom=false) {
                $newcharstring = '';
                if ($bom) {
                        $newcharstring .= "\xFF\xFE";
                }
                for ($i = 0; $i < strlen($string); $i++) {
                        $newcharstring .= $string{$i}."\x00";
                }
                return $newcharstring;
        }
 
        // ISO-8859-1 => UTF-16LE (BOM)
        public static function iconv_fallback_iso88591_utf16($string) {
                return self::iconv_fallback_iso88591_utf16le($string, true);
        }
 
        // UTF-8 => ISO-8859-1
        public static function iconv_fallback_utf8_iso88591($string) {
                if (function_exists('utf8_decode')) {
                        return utf8_decode($string);
                }
                // utf8_decode() unavailable, use getID3()'s iconv_fallback() conversions (possibly PHP is compiled without XML support)
                $newcharstring = '';
                $offset = 0;
                $stringlength = strlen($string);
                while ($offset < $stringlength) {
                        if ((ord($string{$offset}) | 0x07) == 0xF7) {
                                // 11110bbb 10bbbbbb 10bbbbbb 10bbbbbb
                                $charval = ((ord($string{($offset + 0)}) & 0x07) << 18) &
                                                   ((ord($string{($offset + 1)}) & 0x3F) << 12) &
                                                   ((ord($string{($offset + 2)}) & 0x3F) <<  6) &
                                                        (ord($string{($offset + 3)}) & 0x3F);
                                $offset += 4;
                        } elseif ((ord($string{$offset}) | 0x0F) == 0xEF) {
                                // 1110bbbb 10bbbbbb 10bbbbbb
                                $charval = ((ord($string{($offset + 0)}) & 0x0F) << 12) &
                                                   ((ord($string{($offset + 1)}) & 0x3F) <<  6) &
                                                        (ord($string{($offset + 2)}) & 0x3F);
                                $offset += 3;
                        } elseif ((ord($string{$offset}) | 0x1F) == 0xDF) {
                                // 110bbbbb 10bbbbbb
                                $charval = ((ord($string{($offset + 0)}) & 0x1F) <<  6) &
                                                        (ord($string{($offset + 1)}) & 0x3F);
                                $offset += 2;
                        } elseif ((ord($string{$offset}) | 0x7F) == 0x7F) {
                                // 0bbbbbbb
                                $charval = ord($string{$offset});
                                $offset += 1;
                        } else {
                                // error? throw some kind of warning here?
                                $charval = false;
                                $offset += 1;
                        }
                        if ($charval !== false) {
                                $newcharstring .= (($charval < 256) ? chr($charval) : '?');
                        }
                }
                return $newcharstring;
        }
 
        // UTF-8 => UTF-16BE
        public static function iconv_fallback_utf8_utf16be($string, $bom=false) {
                $newcharstring = '';
                if ($bom) {
                        $newcharstring .= "\xFE\xFF";
                }
                $offset = 0;
                $stringlength = strlen($string);
                while ($offset < $stringlength) {
                        if ((ord($string{$offset}) | 0x07) == 0xF7) {
                                // 11110bbb 10bbbbbb 10bbbbbb 10bbbbbb
                                $charval = ((ord($string{($offset + 0)}) & 0x07) << 18) &
                                                   ((ord($string{($offset + 1)}) & 0x3F) << 12) &
                                                   ((ord($string{($offset + 2)}) & 0x3F) <<  6) &
                                                        (ord($string{($offset + 3)}) & 0x3F);
                                $offset += 4;
                        } elseif ((ord($string{$offset}) | 0x0F) == 0xEF) {
                                // 1110bbbb 10bbbbbb 10bbbbbb
                                $charval = ((ord($string{($offset + 0)}) & 0x0F) << 12) &
                                                   ((ord($string{($offset + 1)}) & 0x3F) <<  6) &
                                                        (ord($string{($offset + 2)}) & 0x3F);
                                $offset += 3;
                        } elseif ((ord($string{$offset}) | 0x1F) == 0xDF) {
                                // 110bbbbb 10bbbbbb
                                $charval = ((ord($string{($offset + 0)}) & 0x1F) <<  6) &
                                                        (ord($string{($offset + 1)}) & 0x3F);
                                $offset += 2;
                        } elseif ((ord($string{$offset}) | 0x7F) == 0x7F) {
                                // 0bbbbbbb
                                $charval = ord($string{$offset});
                                $offset += 1;
                        } else {
                                // error? throw some kind of warning here?
                                $charval = false;
                                $offset += 1;
                        }
                        if ($charval !== false) {
                                $newcharstring .= (($charval < 65536) ? self::BigEndian2String($charval, 2) : "\x00".'?');
                        }
                }
                return $newcharstring;
        }
 
        // UTF-8 => UTF-16LE
        public static function iconv_fallback_utf8_utf16le($string, $bom=false) {
                $newcharstring = '';
                if ($bom) {
                        $newcharstring .= "\xFF\xFE";
                }
                $offset = 0;
                $stringlength = strlen($string);
                while ($offset < $stringlength) {
                        if ((ord($string{$offset}) | 0x07) == 0xF7) {
                                // 11110bbb 10bbbbbb 10bbbbbb 10bbbbbb
                                $charval = ((ord($string{($offset + 0)}) & 0x07) << 18) &
                                                   ((ord($string{($offset + 1)}) & 0x3F) << 12) &
                                                   ((ord($string{($offset + 2)}) & 0x3F) <<  6) &
                                                        (ord($string{($offset + 3)}) & 0x3F);
                                $offset += 4;
                        } elseif ((ord($string{$offset}) | 0x0F) == 0xEF) {
                                // 1110bbbb 10bbbbbb 10bbbbbb
                                $charval = ((ord($string{($offset + 0)}) & 0x0F) << 12) &
                                                   ((ord($string{($offset + 1)}) & 0x3F) <<  6) &
                                                        (ord($string{($offset + 2)}) & 0x3F);
                                $offset += 3;
                        } elseif ((ord($string{$offset}) | 0x1F) == 0xDF) {
                                // 110bbbbb 10bbbbbb
                                $charval = ((ord($string{($offset + 0)}) & 0x1F) <<  6) &
                                                        (ord($string{($offset + 1)}) & 0x3F);
                                $offset += 2;
                        } elseif ((ord($string{$offset}) | 0x7F) == 0x7F) {
                                // 0bbbbbbb
                                $charval = ord($string{$offset});
                                $offset += 1;
                        } else {
                                // error? maybe throw some warning here?
                                $charval = false;
                                $offset += 1;
                        }
                        if ($charval !== false) {
                                $newcharstring .= (($charval < 65536) ? self::LittleEndian2String($charval, 2) : '?'."\x00");
                        }
                }
                return $newcharstring;
        }
 
        // UTF-8 => UTF-16LE (BOM)
        public static function iconv_fallback_utf8_utf16($string) {
                return self::iconv_fallback_utf8_utf16le($string, true);
        }
 
        // UTF-16BE => UTF-8
        public static function iconv_fallback_utf16be_utf8($string) {
                if (substr($string, 0, 2) == "\xFE\xFF") {
                        // strip BOM
                        $string = substr($string, 2);
                }
                $newcharstring = '';
                for ($i = 0; $i < strlen($string); $i += 2) {
                        $charval = self::BigEndian2Int(substr($string, $i, 2));
                        $newcharstring .= self::iconv_fallback_int_utf8($charval);
                }
                return $newcharstring;
        }
 
        // UTF-16LE => UTF-8
        public static function iconv_fallback_utf16le_utf8($string) {
                if (substr($string, 0, 2) == "\xFF\xFE") {
                        // strip BOM
                        $string = substr($string, 2);
                }
                $newcharstring = '';
                for ($i = 0; $i < strlen($string); $i += 2) {
                        $charval = self::LittleEndian2Int(substr($string, $i, 2));
                        $newcharstring .= self::iconv_fallback_int_utf8($charval);
                }
                return $newcharstring;
        }
 
        // UTF-16BE => ISO-8859-1
        public static function iconv_fallback_utf16be_iso88591($string) {
                if (substr($string, 0, 2) == "\xFE\xFF") {
                        // strip BOM
                        $string = substr($string, 2);
                }
                $newcharstring = '';
                for ($i = 0; $i < strlen($string); $i += 2) {
                        $charval = self::BigEndian2Int(substr($string, $i, 2));
                        $newcharstring .= (($charval < 256) ? chr($charval) : '?');
                }
                return $newcharstring;
        }
 
        // UTF-16LE => ISO-8859-1
        public static function iconv_fallback_utf16le_iso88591($string) {
                if (substr($string, 0, 2) == "\xFF\xFE") {
                        // strip BOM
                        $string = substr($string, 2);
                }
                $newcharstring = '';
                for ($i = 0; $i < strlen($string); $i += 2) {
                        $charval = self::LittleEndian2Int(substr($string, $i, 2));
                        $newcharstring .= (($charval < 256) ? chr($charval) : '?');
                }
                return $newcharstring;
        }
 
        // UTF-16 (BOM) => ISO-8859-1
        public static function iconv_fallback_utf16_iso88591($string) {
                $bom = substr($string, 0, 2);
                if ($bom == "\xFE\xFF") {
                        return self::iconv_fallback_utf16be_iso88591(substr($string, 2));
                } elseif ($bom == "\xFF\xFE") {
                        return self::iconv_fallback_utf16le_iso88591(substr($string, 2));
                }
                return $string;
        }
 
        // UTF-16 (BOM) => UTF-8
        public static function iconv_fallback_utf16_utf8($string) {
                $bom = substr($string, 0, 2);
                if ($bom == "\xFE\xFF") {
                        return self::iconv_fallback_utf16be_utf8(substr($string, 2));
                } elseif ($bom == "\xFF\xFE") {
                        return self::iconv_fallback_utf16le_utf8(substr($string, 2));
                }
                return $string;
        }
 
        public static function iconv_fallback($in_charset, $out_charset, $string) {
 
                if ($in_charset == $out_charset) {
                        return $string;
                }
 
                // mb_convert_encoding() availble
                if (function_exists('mb_convert_encoding')) {
                        if ($converted_string = @mb_convert_encoding($string, $out_charset, $in_charset)) {
                                switch ($out_charset) {
                                        case 'ISO-8859-1':
                                                $converted_string = rtrim($converted_string, "\x00");
                                                break;
                                }
                                return $converted_string;
                        }
                        return $string;
                }
                // iconv() availble
                else if (function_exists('iconv')) {
                        if ($converted_string = @iconv($in_charset, $out_charset.'//TRANSLIT', $string)) {
                                switch ($out_charset) {
                                        case 'ISO-8859-1':
                                                $converted_string = rtrim($converted_string, "\x00");
                                                break;
                                }
                                return $converted_string;
                        }
 
                        // iconv() may sometimes fail with "illegal character in input string" error message
                        // and return an empty string, but returning the unconverted string is more useful
                        return $string;
                }
 
 
                // neither mb_convert_encoding or iconv() is available
                static $ConversionFunctionList = array();
                if (empty($ConversionFunctionList)) {
                        $ConversionFunctionList['ISO-8859-1']['UTF-8']    = 'iconv_fallback_iso88591_utf8';
                        $ConversionFunctionList['ISO-8859-1']['UTF-16']   = 'iconv_fallback_iso88591_utf16';
                        $ConversionFunctionList['ISO-8859-1']['UTF-16BE'] = 'iconv_fallback_iso88591_utf16be';
                        $ConversionFunctionList['ISO-8859-1']['UTF-16LE'] = 'iconv_fallback_iso88591_utf16le';
                        $ConversionFunctionList['UTF-8']['ISO-8859-1']    = 'iconv_fallback_utf8_iso88591';
                        $ConversionFunctionList['UTF-8']['UTF-16']        = 'iconv_fallback_utf8_utf16';
                        $ConversionFunctionList['UTF-8']['UTF-16BE']      = 'iconv_fallback_utf8_utf16be';
                        $ConversionFunctionList['UTF-8']['UTF-16LE']      = 'iconv_fallback_utf8_utf16le';
                        $ConversionFunctionList['UTF-16']['ISO-8859-1']   = 'iconv_fallback_utf16_iso88591';
                        $ConversionFunctionList['UTF-16']['UTF-8']        = 'iconv_fallback_utf16_utf8';
                        $ConversionFunctionList['UTF-16LE']['ISO-8859-1'] = 'iconv_fallback_utf16le_iso88591';
                        $ConversionFunctionList['UTF-16LE']['UTF-8']      = 'iconv_fallback_utf16le_utf8';
                        $ConversionFunctionList['UTF-16BE']['ISO-8859-1'] = 'iconv_fallback_utf16be_iso88591';
                        $ConversionFunctionList['UTF-16BE']['UTF-8']      = 'iconv_fallback_utf16be_utf8';
                }
                if (isset($ConversionFunctionList[strtoupper($in_charset)][strtoupper($out_charset)])) {
                        $ConversionFunction = $ConversionFunctionList[strtoupper($in_charset)][strtoupper($out_charset)];
                        return self::$ConversionFunction($string);
                }
                throw new Exception('PHP does not has mb_convert_encoding() or iconv() support - cannot convert from '.$in_charset.' to '.$out_charset);
        }
 
        public static function recursiveMultiByteCharString2HTML($data, $charset='ISO-8859-1') {
                if (is_string($data)) {
                        return self::MultiByteCharString2HTML($data, $charset);
                } elseif (is_array($data)) {
                        $return_data = array();
                        foreach ($data as $key => $value) {
                                $return_data[$key] = self::recursiveMultiByteCharString2HTML($value, $charset);
                        }
                        return $return_data;
                }
                // integer, float, objects, resources, etc
                return $data;
        }
 
        public static function MultiByteCharString2HTML($string, $charset='ISO-8859-1') {
                $string = (string) $string; // in case trying to pass a numeric (float, int) string, would otherwise return an empty string
                $HTMLstring = '';
 
                switch (strtolower($charset)) {
                        case '1251':
                        case '1252':
                        case '866':
                        case '932':
                        case '936':
                        case '950':
                        case 'big5':
                        case 'big5-hkscs':
                        case 'cp1251':
                        case 'cp1252':
                        case 'cp866':
                        case 'euc-jp':
                        case 'eucjp':
                        case 'gb2312':
                        case 'ibm866':
                        case 'iso-8859-1':
                        case 'iso-8859-15':
                        case 'iso8859-1':
                        case 'iso8859-15':
                        case 'koi8-r':
                        case 'koi8-ru':
                        case 'koi8r':
                        case 'shift_jis':
                        case 'sjis':
                        case 'win-1251':
                        case 'windows-1251':
                        case 'windows-1252':
                                $HTMLstring = htmlentities($string, ENT_COMPAT, $charset);
                                break;
 
                        case 'utf-8':
                                $strlen = strlen($string);
                                for ($i = 0; $i < $strlen; $i++) {
                                        $char_ord_val = ord($string{$i});
                                        $charval = 0;
                                        if ($char_ord_val < 0x80) {
                                                $charval = $char_ord_val;
                                        } elseif ((($char_ord_val & 0xF0) >> 4) == 0x0F  &&  $i+3 < $strlen) {
                                                $charval  = (($char_ord_val & 0x07) << 18);
                                                $charval += ((ord($string{++$i}) & 0x3F) << 12);
                                                $charval += ((ord($string{++$i}) & 0x3F) << 6);
                                                $charval +=  (ord($string{++$i}) & 0x3F);
                                        } elseif ((($char_ord_val & 0xE0) >> 5) == 0x07  &&  $i+2 < $strlen) {
                                                $charval  = (($char_ord_val & 0x0F) << 12);
                                                $charval += ((ord($string{++$i}) & 0x3F) << 6);
                                                $charval +=  (ord($string{++$i}) & 0x3F);
                                        } elseif ((($char_ord_val & 0xC0) >> 6) == 0x03  &&  $i+1 < $strlen) {
                                                $charval  = (($char_ord_val & 0x1F) << 6);
                                                $charval += (ord($string{++$i}) & 0x3F);
                                        }
                                        if (($charval >= 32) && ($charval <= 127)) {
                                                $HTMLstring .= htmlentities(chr($charval));
                                        } else {
                                                $HTMLstring .= '&#'.$charval.';';
                                        }
                                }
                                break;
 
                        case 'utf-16le':
                                for ($i = 0; $i < strlen($string); $i += 2) {
                                        $charval = self::LittleEndian2Int(substr($string, $i, 2));
                                        if (($charval >= 32) && ($charval <= 127)) {
                                                $HTMLstring .= chr($charval);
                                        } else {
                                                $HTMLstring .= '&#'.$charval.';';
                                        }
                                }
                                break;
 
                        case 'utf-16be':
                                for ($i = 0; $i < strlen($string); $i += 2) {
                                        $charval = self::BigEndian2Int(substr($string, $i, 2));
                                        if (($charval >= 32) && ($charval <= 127)) {
                                                $HTMLstring .= chr($charval);
                                        } else {
                                                $HTMLstring .= '&#'.$charval.';';
                                        }
                                }
                                break;
 
                        default:
                                $HTMLstring = 'ERROR: Character set "'.$charset.'" not supported in MultiByteCharString2HTML()';
                                break;
                }
                return $HTMLstring;
        }
 
 
 
        public static function RGADnameLookup($namecode) {
                static $RGADname = array();
                if (empty($RGADname)) {
                        $RGADname[0] = 'not set';
                        $RGADname[1] = 'Track Gain Adjustment';
                        $RGADname[2] = 'Album Gain Adjustment';
                }
 
                return (isset($RGADname[$namecode]) ? $RGADname[$namecode] : '');
        }
 
 
        public static function RGADoriginatorLookup($originatorcode) {
                static $RGADoriginator = array();
                if (empty($RGADoriginator)) {
                        $RGADoriginator[0] = 'unspecified';
                        $RGADoriginator[1] = 'pre-set by artist/producer/mastering engineer';
                        $RGADoriginator[2] = 'set by user';
                        $RGADoriginator[3] = 'determined automatically';
                }
 
                return (isset($RGADoriginator[$originatorcode]) ? $RGADoriginator[$originatorcode] : '');
        }
 
 
        public static function RGADadjustmentLookup($rawadjustment, $signbit) {
                $adjustment = $rawadjustment / 10;
                if ($signbit == 1) {
                        $adjustment *= -1;
                }
                return (float) $adjustment;
        }
 
 
        public static function RGADgainString($namecode, $originatorcode, $replaygain) {
                if ($replaygain < 0) {
                        $signbit = '1';
                } else {
                        $signbit = '0';
                }
                $storedreplaygain = intval(round($replaygain * 10));
                $gainstring  = str_pad(decbin($namecode), 3, '0', STR_PAD_LEFT);
                $gainstring .= str_pad(decbin($originatorcode), 3, '0', STR_PAD_LEFT);
                $gainstring .= $signbit;
                $gainstring .= str_pad(decbin($storedreplaygain), 9, '0', STR_PAD_LEFT);
 
                return $gainstring;
        }
 
        public static function RGADamplitude2dB($amplitude) {
                return 20 * log10($amplitude);
        }
 
 
        public static function GetDataImageSize($imgData, &$imageinfo=array()) {
                static $tempdir = '';
                if (empty($tempdir)) {
                        if (function_exists('sys_get_temp_dir')) {
                                $tempdir = sys_get_temp_dir(); // https://github.com/JamesHeinrich/getID3/issues/52
                        }
 
                        // yes this is ugly, feel free to suggest a better way
                        if (include_once(dirname(__FILE__).'/getid3.php')) {
                                if ($getid3_temp = new getID3()) {
                                        if ($getid3_temp_tempdir = $getid3_temp->tempdir) {
                                                $tempdir = $getid3_temp_tempdir;
                                        }
                                        unset($getid3_temp, $getid3_temp_tempdir);
                                }
                        }
                }
                $GetDataImageSize = false;
                if ($tempfilename = tempnam($tempdir, 'gI3')) {
                        if (is_writable($tempfilename) && is_file($tempfilename) && ($tmp = fopen($tempfilename, 'wb'))) {
                                fwrite($tmp, $imgData);
                                fclose($tmp);
                                $GetDataImageSize = @getimagesize($tempfilename, $imageinfo);
                                if (($GetDataImageSize === false) || !isset($GetDataImageSize[0]) || !isset($GetDataImageSize[1])) {
                                        return false;
                                }
                                $GetDataImageSize['height'] = $GetDataImageSize[0];
                                $GetDataImageSize['width']  = $GetDataImageSize[1];
                        }
                        unlink($tempfilename);
                }
                return $GetDataImageSize;
        }
 
        public static function ImageExtFromMime($mime_type) {
                // temporary way, works OK for now, but should be reworked in the future
                return str_replace(array('image/', 'x-', 'jpeg'), array('', '', 'jpg'), $mime_type);
        }
 
        public static function ImageTypesLookup($imagetypeid) {
                static $ImageTypesLookup = array();
                if (empty($ImageTypesLookup)) {
                        $ImageTypesLookup[1]  = 'gif';
                        $ImageTypesLookup[2]  = 'jpeg';
                        $ImageTypesLookup[3]  = 'png';
                        $ImageTypesLookup[4]  = 'swf';
                        $ImageTypesLookup[5]  = 'psd';
                        $ImageTypesLookup[6]  = 'bmp';
                        $ImageTypesLookup[7]  = 'tiff (little-endian)';
                        $ImageTypesLookup[8]  = 'tiff (big-endian)';
                        $ImageTypesLookup[9]  = 'jpc';
                        $ImageTypesLookup[10] = 'jp2';
                        $ImageTypesLookup[11] = 'jpx';
                        $ImageTypesLookup[12] = 'jb2';
                        $ImageTypesLookup[13] = 'swc';
                        $ImageTypesLookup[14] = 'iff';
                }
                return (isset($ImageTypesLookup[$imagetypeid]) ? $ImageTypesLookup[$imagetypeid] : '');
        }
 
        public static function CopyTagsToComments(&$ThisFileInfo) {
 
                // Copy all entries from ['tags'] into common ['comments']
                if (!empty($ThisFileInfo['tags'])) {
                        foreach ($ThisFileInfo['tags'] as $tagtype => $tagarray) {
                                foreach ($tagarray as $tagname => $tagdata) {
                                        foreach ($tagdata as $key => $value) {
                                                if (!empty($value)) {
                                                        if (empty($ThisFileInfo['comments'][$tagname])) {
 
                                                                // fall through and append value
 
                                                        } elseif ($tagtype == 'id3v1') {
 
                                                                $newvaluelength = strlen(trim($value));
                                                                foreach ($ThisFileInfo['comments'][$tagname] as $existingkey => $existingvalue) {
                                                                        $oldvaluelength = strlen(trim($existingvalue));
                                                                        if (($newvaluelength <= $oldvaluelength) && (substr($existingvalue, 0, $newvaluelength) == trim($value))) {
                                                                                // new value is identical but shorter-than (or equal-length to) one already in comments - skip
                                                                                break 2;
                                                                        }
                                                                }
 
                                                        } elseif (!is_array($value)) {
 
                                                                $newvaluelength = strlen(trim($value));
                                                                foreach ($ThisFileInfo['comments'][$tagname] as $existingkey => $existingvalue) {
                                                                        $oldvaluelength = strlen(trim($existingvalue));
                                                                        if ((strlen($existingvalue) > 10) && ($newvaluelength > $oldvaluelength) && (substr(trim($value), 0, strlen($existingvalue)) == $existingvalue)) {
                                                                                $ThisFileInfo['comments'][$tagname][$existingkey] = trim($value);
                                                                                //break 2;
                                                                                break;
                                                                        }
                                                                }
 
                                                        }
                                                        if (is_array($value) || empty($ThisFileInfo['comments'][$tagname]) || !in_array(trim($value), $ThisFileInfo['comments'][$tagname])) {
                                                                $value = (is_string($value) ? trim($value) : $value);
                                                                if (!is_int($key) && !ctype_digit($key)) {
                                                                        $ThisFileInfo['comments'][$tagname][$key] = $value;
                                                                } else {
                                                                        if (isset($ThisFileInfo['comments'][$tagname])) {
                                                                                $ThisFileInfo['comments'][$tagname] = array($value);
                                                                        } else {
                                                                                $ThisFileInfo['comments'][$tagname][] = $value;
                                                                        }
                                                                }
                                                        }
                                                }
                                        }
                                }
                        }
 
                        // attempt to standardize spelling of returned keys
                        $StandardizeFieldNames = array(
                                'tracknumber' => 'track_number',
                                'track'       => 'track_number',
                        );
                        foreach ($StandardizeFieldNames as $badkey => $goodkey) {
                                if (array_key_exists($badkey, $ThisFileInfo['comments']) && !array_key_exists($goodkey, $ThisFileInfo['comments'])) {
                                        $ThisFileInfo['comments'][$goodkey] = $ThisFileInfo['comments'][$badkey];
                                        unset($ThisFileInfo['comments'][$badkey]);
                                }
                        }
 
                        // Copy to ['comments_html']
                        if (!empty($ThisFileInfo['comments'])) {
                                foreach ($ThisFileInfo['comments'] as $field => $values) {
                                        if ($field == 'picture') {
                                                // pictures can take up a lot of space, and we don't need multiple copies of them
                                                // let there be a single copy in [comments][picture], and not elsewhere
                                                continue;
                                        }
                                        foreach ($values as $index => $value) {
                                                if (is_array($value)) {
                                                        $ThisFileInfo['comments_html'][$field][$index] = $value;
                                                } else {
                                                        $ThisFileInfo['comments_html'][$field][$index] = str_replace('&#0;', '', self::MultiByteCharString2HTML($value, $ThisFileInfo['encoding']));
                                                }
                                        }
                                }
                        }
 
                }
                return true;
        }
 
 
        public static function EmbeddedLookup($key, $begin, $end, $file, $name) {
 
                // Cached
                static $cache;
                if (isset($cache[$file][$name])) {
                        return (isset($cache[$file][$name][$key]) ? $cache[$file][$name][$key] : '');
                }
 
                // Init
                $keylength  = strlen($key);
                $line_count = $end - $begin - 7;
 
                // Open php file
                $fp = fopen($file, 'r');
 
                // Discard $begin lines
                for ($i = 0; $i < ($begin + 3); $i++) {
                        fgets($fp, 1024);
                }
 
                // Loop thru line
                while (0 < $line_count--) {
 
                        // Read line
                        $line = ltrim(fgets($fp, 1024), "\t ");
 
                        // METHOD A: only cache the matching key - less memory but slower on next lookup of not-previously-looked-up key
                        //$keycheck = substr($line, 0, $keylength);
                        //if ($key == $keycheck)  {
                        //      $cache[$file][$name][$keycheck] = substr($line, $keylength + 1);
                        //      break;
                        //}
 
                        // METHOD B: cache all keys in this lookup - more memory but faster on next lookup of not-previously-looked-up key
                        //$cache[$file][$name][substr($line, 0, $keylength)] = trim(substr($line, $keylength + 1));
                        $explodedLine = explode("\t", $line, 2);
                        $ThisKey   = (isset($explodedLine[0]) ? $explodedLine[0] : '');
                        $ThisValue = (isset($explodedLine[1]) ? $explodedLine[1] : '');
                        $cache[$file][$name][$ThisKey] = trim($ThisValue);
                }
 
                // Close and return
                fclose($fp);
                return (isset($cache[$file][$name][$key]) ? $cache[$file][$name][$key] : '');
        }
 
        public static function IncludeDependency($filename, $sourcefile, $DieOnFailure=false) {
                global $GETID3_ERRORARRAY;
 
                if (file_exists($filename)) {
                        if (include_once($filename)) {
                                return true;
                        } else {
                                $diemessage = basename($sourcefile).' depends on '.$filename.', which has errors';
                        }
                } else {
                        $diemessage = basename($sourcefile).' depends on '.$filename.', which is missing';
                }
                if ($DieOnFailure) {
                        throw new Exception($diemessage);
                } else {
                        $GETID3_ERRORARRAY[] = $diemessage;
                }
                return false;
        }
 
        public static function trimNullByte($string) {
                return trim($string, "\x00");
        }
 
        public static function getFileSizeSyscall($path) {
                $filesize = false;
 
                if (GETID3_OS_ISWINDOWS) {
                        if (class_exists('COM')) { // From PHP 5.3.15 and 5.4.5, COM and DOTNET is no longer built into the php core.you have to add COM support in php.ini:
                                $filesystem = new COM('Scripting.FileSystemObject');
                                $file = $filesystem->GetFile($path);
                                $filesize = $file->Size();
                                unset($filesystem, $file);
                        } else {
                                $commandline = 'for %I in ('.escapeshellarg($path).') do @echo %~zI';
                        }
                } else {
                        $commandline = 'ls -l '.escapeshellarg($path).' | awk \'{print $5}\'';
                }
                if (isset($commandline)) {
                        $output = trim(`$commandline`);
                        if (ctype_digit($output)) {
                                $filesize = (float) $output;
                        }
                }
                return $filesize;
        }
 
 
        public static function mb_basename($path, $suffix = null) {
                $splited = preg_split('#/#', rtrim($path, '/ '));
                return substr(basename('X'.$splited[count($splited) - 1], $suffix), 1);
        }
 
}