website/vendor/getid3/getid3.php

<?php
/////////////////////////////////////////////////////////////////
/// getID3() by James Heinrich <info@getid3.org>               //
//  available at https://github.com/JamesHeinrich/getID3       //
//            or https://www.getid3.org                        //
//            or http://getid3.sourceforge.net                 //
//                                                             //
// Please see readme.txt for more information                  //
//                                                            ///
/////////////////////////////////////////////////////////////////

// define a constant rather than looking up every time it is needed
if (!defined('GETID3_OS_ISWINDOWS')) {
	define('GETID3_OS_ISWINDOWS', (stripos(PHP_OS, 'WIN') === 0));
}
// Get base path of getID3() - ONCE
if (!defined('GETID3_INCLUDEPATH')) {
	define('GETID3_INCLUDEPATH', dirname(__FILE__).DIRECTORY_SEPARATOR);
}
// Workaround Bug #39923 (https://bugs.php.net/bug.php?id=39923)
if (!defined('IMG_JPG') && defined('IMAGETYPE_JPEG')) {
	define('IMG_JPG', IMAGETYPE_JPEG);
}
if (!defined('ENT_SUBSTITUTE')) { // PHP5.3 adds ENT_IGNORE, PHP5.4 adds ENT_SUBSTITUTE
	define('ENT_SUBSTITUTE', (defined('ENT_IGNORE') ? ENT_IGNORE : 8));
}

/*
https://www.getid3.org/phpBB3/viewtopic.php?t=2114
If you are running into a the problem where filenames with special characters are being handled
incorrectly by external helper programs (e.g. metaflac), notably with the special characters removed,
and you are passing in the filename in UTF8 (typically via a HTML form), try uncommenting this line:
*/
//setlocale(LC_CTYPE, 'en_US.UTF-8');

// attempt to define temp dir as something flexible but reliable
$temp_dir = ini_get('upload_tmp_dir');
if ($temp_dir && (!is_dir($temp_dir) || !is_readable($temp_dir))) {
	$temp_dir = '';
}
if (!$temp_dir && function_exists('sys_get_temp_dir')) { // sys_get_temp_dir added in PHP v5.2.1
	// sys_get_temp_dir() may give inaccessible temp dir, e.g. with open_basedir on virtual hosts
	$temp_dir = sys_get_temp_dir();
}
$temp_dir = @realpath($temp_dir); // see https://github.com/JamesHeinrich/getID3/pull/10
$open_basedir = ini_get('open_basedir');
if ($open_basedir) {
	// e.g. "/var/www/vhosts/getid3.org/httpdocs/:/tmp/"
	$temp_dir     = str_replace(array('/', '\\'), DIRECTORY_SEPARATOR, $temp_dir);
	$open_basedir = str_replace(array('/', '\\'), DIRECTORY_SEPARATOR, $open_basedir);
	if (substr($temp_dir, -1, 1) != DIRECTORY_SEPARATOR) {
		$temp_dir .= DIRECTORY_SEPARATOR;
	}
	$found_valid_tempdir = false;
	$open_basedirs = explode(PATH_SEPARATOR, $open_basedir);
	foreach ($open_basedirs as $basedir) {
		if (substr($basedir, -1, 1) != DIRECTORY_SEPARATOR) {
			$basedir .= DIRECTORY_SEPARATOR;
		}
		if (preg_match('#^'.preg_quote($basedir).'#', $temp_dir)) {
			$found_valid_tempdir = true;
			break;
		}
	}
	if (!$found_valid_tempdir) {
		$temp_dir = '';
	}
	unset($open_basedirs, $found_valid_tempdir, $basedir);
}
if (!$temp_dir) {
	$temp_dir = '*'; // invalid directory name should force tempnam() to use system default temp dir
}
// $temp_dir = '/something/else/';  // feel free to override temp dir here if it works better for your system
if (!defined('GETID3_TEMP_DIR')) {
	define('GETID3_TEMP_DIR', $temp_dir);
}
unset($open_basedir, $temp_dir);

// End: Defines


class getID3
{
	/*
	 * Settings
	 */

	/**
	 * CASE SENSITIVE! - i.e. (must be supported by iconv()). Examples:  ISO-8859-1  UTF-8  UTF-16  UTF-16BE
	 *
	 * @var string
	 */
	public $encoding        = 'UTF-8';

	/**
	 * Should always be 'ISO-8859-1', but some tags may be written in other encodings such as 'EUC-CN' or 'CP1252'
	 *
	 * @var string
	 */
	public $encoding_id3v1  = 'ISO-8859-1';

	/**
	 * ID3v1 should always be 'ISO-8859-1', but some tags may be written in other encodings such as 'Windows-1251' or 'KOI8-R'. If true attempt to detect these encodings, but may return incorrect values for some tags actually in ISO-8859-1 encoding
	 *
	 * @var bool
	 */
	public $encoding_id3v1_autodetect  = false;

	/*
	 * Optional tag checks - disable for speed.
	 */

	/**
	 * Read and process ID3v1 tags
	 *
	 * @var bool
	 */
	public $option_tag_id3v1         = true;

	/**
	 * Read and process ID3v2 tags
	 *
	 * @var bool
	 */
	public $option_tag_id3v2         = true;

	/**
	 * Read and process Lyrics3 tags
	 *
	 * @var bool
	 */
	public $option_tag_lyrics3       = true;

	/**
	 * Read and process APE tags
	 *
	 * @var bool
	 */
	public $option_tag_apetag        = true;

	/**
	 * Copy tags to root key 'tags' and encode to $this->encoding
	 *
	 * @var bool
	 */
	public $option_tags_process      = true;

	/**
	 * Copy tags to root key 'tags_html' properly translated from various encodings to HTML entities
	 *
	 * @var bool
	 */
	public $option_tags_html         = true;

	/*
	 * Optional tag/comment calculations
	 */

	/**
	 * Calculate additional info such as bitrate, channelmode etc
	 *
	 * @var bool
	 */
	public $option_extra_info        = true;

	/*
	 * Optional handling of embedded attachments (e.g. images)
	 */

	/**
	 * Defaults to true (ATTACHMENTS_INLINE) for backward compatibility
	 *
	 * @var bool|string
	 */
	public $option_save_attachments  = true;

	/*
	 * Optional calculations
	 */

	/**
	 * Get MD5 sum of data part - slow
	 *
	 * @var bool
	 */
	public $option_md5_data          = false;

	/**
	 * Use MD5 of source file if availble - only FLAC and OptimFROG
	 *
	 * @var bool
	 */
	public $option_md5_data_source   = false;

	/**
	 * Get SHA1 sum of data part - slow
	 *
	 * @var bool
	 */
	public $option_sha1_data         = false;

	/**
	 * Check whether file is larger than 2GB and thus not supported by 32-bit PHP (null: auto-detect based on
	 * PHP_INT_MAX)
	 *
	 * @var bool|null
	 */
	public $option_max_2gb_check;

	/**
	 * Read buffer size in bytes
	 *
	 * @var int
	 */
	public $option_fread_buffer_size = 32768;

	// Public variables

	/**
	 * Filename of file being analysed.
	 *
	 * @var string
	 */
	public $filename;

	/**
	 * Filepointer to file being analysed.
	 *
	 * @var resource
	 */
	public $fp;

	/**
	 * Result array.
	 *
	 * @var array
	 */
	public $info;

	/**
	 * @var string
	 */
	public $tempdir = GETID3_TEMP_DIR;

	/**
	 * @var int
	 */
	public $memory_limit = 0;

	/**
	 * @var string
	 */
	protected $startup_error   = '';

	/**
	 * @var string
	 */
	protected $startup_warning = '';

	const VERSION           = '1.9.19-202003150936';
	const FREAD_BUFFER_SIZE = 32768;

	const ATTACHMENTS_NONE   = false;
	const ATTACHMENTS_INLINE = true;

	public function __construct() {

		// Check for PHP version
		$required_php_version = '5.3.0';
		if (version_compare(PHP_VERSION, $required_php_version, '<')) {
			$this->startup_error .= 'getID3() requires PHP v'.$required_php_version.' or higher - you are running v'.PHP_VERSION."\n";
			return;
		}

		// Check memory
		$memoryLimit = ini_get('memory_limit');
		if (preg_match('#([0-9]+) ?M#i', $memoryLimit, $matches)) {
			// could be stored as "16M" rather than 16777216 for example
			$memoryLimit = $matches[1] * 1048576;
		} elseif (preg_match('#([0-9]+) ?G#i', $memoryLimit, $matches)) { // The 'G' modifier is available since PHP 5.1.0
			// could be stored as "2G" rather than 2147483648 for example
			$memoryLimit = $matches[1] * 1073741824;
		}
		$this->memory_limit = $memoryLimit;

		if ($this->memory_limit <= 0) {
			// memory limits probably disabled
		} elseif ($this->memory_limit <= 4194304) {
			$this->startup_error .= 'PHP has less than 4MB available memory and will very likely run out. Increase memory_limit in php.ini'."\n";
		} elseif ($this->memory_limit <= 12582912) {
			$this->startup_warning .= 'PHP has less than 12MB available memory and might run out if all modules are loaded. Increase memory_limit in php.ini'."\n";
		}

		// Check safe_mode off
		if (preg_match('#(1|ON)#i', ini_get('safe_mode'))) {
			$this->warning('WARNING: Safe mode is on, shorten support disabled, md5data/sha1data for ogg vorbis disabled, ogg vorbos/flac tag writing disabled.');
		}

		if (($mbstring_func_overload = (int) ini_get('mbstring.func_overload')) && ($mbstring_func_overload & 0x02)) {
			// http://php.net/manual/en/mbstring.overload.php
			// "mbstring.func_overload in php.ini is a positive value that represents a combination of bitmasks specifying the categories of functions to be overloaded. It should be set to 1 to overload the mail() function. 2 for string functions, 4 for regular expression functions"
			// getID3 cannot run when string functions are overloaded. It doesn't matter if mail() or ereg* functions are overloaded since getID3 does not use those.
			$this->startup_error .= 'WARNING: php.ini contains "mbstring.func_overload = '.ini_get('mbstring.func_overload').'", getID3 cannot run with this setting (bitmask 2 (string functions) cannot be set). Recommended to disable entirely.'."\n";
		}

		// check for magic quotes in PHP < 7.4.0 (when these functions became deprecated)
		if (version_compare(PHP_VERSION, '7.4.0', '<')) {
			// Check for magic_quotes_runtime
			if (function_exists('get_magic_quotes_runtime')) {
				if (get_magic_quotes_runtime()) {
					$this->startup_error .= 'magic_quotes_runtime must be disabled before running getID3(). Surround getid3 block by set_magic_quotes_runtime(0) and set_magic_quotes_runtime(1).'."\n";
				}
			}
			// Check for magic_quotes_gpc
			if (function_exists('get_magic_quotes_gpc')) {
				if (get_magic_quotes_gpc()) {
					$this->startup_error .= 'magic_quotes_gpc must be disabled before running getID3(). Surround getid3 block by set_magic_quotes_gpc(0) and set_magic_quotes_gpc(1).'."\n";
				}
			}
		}

		// Load support library
		if (!include_once(GETID3_INCLUDEPATH.'getid3.lib.php')) {
			$this->startup_error .= 'getid3.lib.php is missing or corrupt'."\n";
		}

		if ($this->option_max_2gb_check === null) {
			$this->option_max_2gb_check = (PHP_INT_MAX <= 2147483647);
		}


		// Needed for Windows only:
		// Define locations of helper applications for Shorten, VorbisComment, MetaFLAC
		//   as well as other helper functions such as head, etc
		// This path cannot contain spaces, but the below code will attempt to get the
		//   8.3-equivalent path automatically
		// IMPORTANT: This path must include the trailing slash
		if (GETID3_OS_ISWINDOWS && !defined('GETID3_HELPERAPPSDIR')) {

			$helperappsdir = GETID3_INCLUDEPATH.'..'.DIRECTORY_SEPARATOR.'helperapps'; // must not have any space in this path

			if (!is_dir($helperappsdir)) {
				$this->startup_warning .= '"'.$helperappsdir.'" cannot be defined as GETID3_HELPERAPPSDIR because it does not exist'."\n";
			} elseif (strpos(realpath($helperappsdir), ' ') !== false) {
				$DirPieces = explode(DIRECTORY_SEPARATOR, realpath($helperappsdir));
				$path_so_far = array();
				foreach ($DirPieces as $key => $value) {
					if (strpos($value, ' ') !== false) {
						if (!empty($path_so_far)) {
							$commandline = 'dir /x '.escapeshellarg(implode(DIRECTORY_SEPARATOR, $path_so_far));
							$dir_listing = `$commandline`;
							$lines = explode("\n", $dir_listing);
							foreach ($lines as $line) {
								$line = trim($line);
								if (preg_match('#^([0-9/]{10}) +([0-9:]{4,5}( [AP]M)?) +(<DIR>|[0-9,]+) +([^ ]{0,11}) +(.+)$#', $line, $matches)) {
									list($dummy, $date, $time, $ampm, $filesize, $shortname, $filename) = $matches;
									if ((strtoupper($filesize) == '<DIR>') && (strtolower($filename) == strtolower($value))) {
										$value = $shortname;
									}
								}
							}
						} else {
							$this->startup_warning .= 'GETID3_HELPERAPPSDIR must not have any spaces in it - use 8dot3 naming convention if neccesary. You can run "dir /x" from the commandline to see the correct 8.3-style names.'."\n";
						}
					}
					$path_so_far[] = $value;
				}
				$helperappsdir = implode(DIRECTORY_SEPARATOR, $path_so_far);
			}
			define('GETID3_HELPERAPPSDIR', $helperappsdir.DIRECTORY_SEPARATOR);
		}

		if (!empty($this->startup_error)) {
			echo $this->startup_error;
			throw new getid3_exception($this->startup_error);
		}
	}

	/**
	 * @return string
	 */
	public function version() {
		return self::VERSION;
	}

	/**
	 * @return int
	 */
	public function fread_buffer_size() {
		return $this->option_fread_buffer_size;
	}

	/**
	 * @param array $optArray
	 *
	 * @return bool
	 */
	public function setOption($optArray) {
		if (!is_array($optArray) || empty($optArray)) {
			return false;
		}
		foreach ($optArray as $opt => $val) {
			if (isset($this->$opt) === false) {
				continue;
			}
			$this->$opt = $val;
		}
		return true;
	}

	/**
	 * @param string   $filename
	 * @param int      $filesize
	 * @param resource $fp
	 *
	 * @return bool
	 *
	 * @throws getid3_exception
	 */
	public function openfile($filename, $filesize=null, $fp=null) {
		try {
			if (!empty($this->startup_error)) {
				throw new getid3_exception($this->startup_error);
			}
			if (!empty($this->startup_warning)) {
				foreach (explode("\n", $this->startup_warning) as $startup_warning) {
					$this->warning($startup_warning);
				}
			}

			// init result array and set parameters
			$this->filename = $filename;
			$this->info = array();
			$this->info['GETID3_VERSION']   = $this->version();
			$this->info['php_memory_limit'] = (($this->memory_limit > 0) ? $this->memory_limit : false);

			// remote files not supported
			if (preg_match('#^(ht|f)tp://#', $filename)) {
				throw new getid3_exception('Remote files are not supported - please copy the file locally first');
			}

			$filename = str_replace('/', DIRECTORY_SEPARATOR, $filename);
			//$filename = preg_replace('#(?<!gs:)('.preg_quote(DIRECTORY_SEPARATOR).'{2,})#', DIRECTORY_SEPARATOR, $filename);

			// open local file
			//if (is_readable($filename) && is_file($filename) && ($this->fp = fopen($filename, 'rb'))) { // see https://www.getid3.org/phpBB3/viewtopic.php?t=1720
			if (($fp != null) && ((get_resource_type($fp) == 'file') || (get_resource_type($fp) == 'stream'))) {
				$this->fp = $fp;
			} elseif ((is_readable($filename) || file_exists($filename)) && is_file($filename) && ($this->fp = fopen($filename, 'rb'))) {
				// great
			} else {
				$errormessagelist = array();
				if (!is_readable($filename)) {
					$errormessagelist[] = '!is_readable';
				}
				if (!is_file($filename)) {
					$errormessagelist[] = '!is_file';
				}
				if (!file_exists($filename)) {
					$errormessagelist[] = '!file_exists';
				}
				if (empty($errormessagelist)) {
					$errormessagelist[] = 'fopen failed';
				}
				throw new getid3_exception('Could not open "'.$filename.'" ('.implode('; ', $errormessagelist).')');
			}

			$this->info['filesize'] = (!is_null($filesize) ? $filesize : filesize($filename));
			// set redundant parameters - might be needed in some include file
			// filenames / filepaths in getID3 are always expressed with forward slashes (unix-style) for both Windows and other to try and minimize confusion
			$filename = str_replace('\\', '/', $filename);
			$this->info['filepath']     = str_replace('\\', '/', realpath(dirname($filename)));
			$this->info['filename']     = getid3_lib::mb_basename($filename);
			$this->info['filenamepath'] = $this->info['filepath'].'/'.$this->info['filename'];

			// set more parameters
			$this->info['avdataoffset']        = 0;
			$this->info['avdataend']           = $this->info['filesize'];
			$this->info['fileformat']          = '';                // filled in later
			$this->info['audio']['dataformat'] = '';                // filled in later, unset if not used
			$this->info['video']['dataformat'] = '';                // filled in later, unset if not used
			$this->info['tags']                = array();           // filled in later, unset if not used
			$this->info['error']               = array();           // filled in later, unset if not used
			$this->info['warning']             = array();           // filled in later, unset if not used
			$this->info['comments']            = array();           // filled in later, unset if not used
			$this->info['encoding']            = $this->encoding;   // required by id3v2 and iso modules - can be unset at the end if desired

			// option_max_2gb_check
			if ($this->option_max_2gb_check) {
				// PHP (32-bit all, and 64-bit Windows) doesn't support integers larger than 2^31 (~2GB)
				// filesize() simply returns (filesize % (pow(2, 32)), no matter the actual filesize
				// ftell() returns 0 if seeking to the end is beyond the range of unsigned integer
				$fseek = fseek($this->fp, 0, SEEK_END);
				if (($fseek < 0) || (($this->info['filesize'] != 0) && (ftell($this->fp) == 0)) ||
					($this->info['filesize'] < 0) ||
					(ftell($this->fp) < 0)) {
						$real_filesize = getid3_lib::getFileSizeSyscall($this->info['filenamepath']);

						if ($real_filesize === false) {
							unset($this->info['filesize']);
							fclose($this->fp);
							throw new getid3_exception('Unable to determine actual filesize. File is most likely larger than '.round(PHP_INT_MAX / 1073741824).'GB and is not supported by PHP.');
						} elseif (getid3_lib::intValueSupported($real_filesize)) {
							unset($this->info['filesize']);
							fclose($this->fp);
							throw new getid3_exception('PHP seems to think the file is larger than '.round(PHP_INT_MAX / 1073741824).'GB, but filesystem reports it as '.number_format($real_filesize / 1073741824, 3).'GB, please report to info@getid3.org');
						}
						$this->info['filesize'] = $real_filesize;
						$this->warning('File is larger than '.round(PHP_INT_MAX / 1073741824).'GB (filesystem reports it as '.number_format($real_filesize / 1073741824, 3).'GB) and is not properly supported by PHP.');
				}
			}

			return true;

		} catch (Exception $e) {
			$this->error($e->getMessage());
		}
		return false;
	}

	/**
	 * analyze file
	 *
	 * @param string   $filename
	 * @param int      $filesize
	 * @param string   $original_filename
	 * @param resource $fp
	 *
	 * @return array
	 */
	public function analyze($filename, $filesize=null, $original_filename='', $fp=null) {
		try {
			if (!$this->openfile($filename, $filesize, $fp)) {
				return $this->info;
			}

			// Handle tags
			foreach (array('id3v2'=>'id3v2', 'id3v1'=>'id3v1', 'apetag'=>'ape', 'lyrics3'=>'lyrics3') as $tag_name => $tag_key) {
				$option_tag = 'option_tag_'.$tag_name;
				if ($this->$option_tag) {
					$this->include_module('tag.'.$tag_name);
					try {
						$tag_class = 'getid3_'.$tag_name;
						$tag = new $tag_class($this);
						$tag->Analyze();
					}
					catch (getid3_exception $e) {
						throw $e;
					}
				}
			}
			if (isset($this->info['id3v2']['tag_offset_start'])) {
				$this->info['avdataoffset'] = max($this->info['avdataoffset'], $this->info['id3v2']['tag_offset_end']);
			}
			foreach (array('id3v1'=>'id3v1', 'apetag'=>'ape', 'lyrics3'=>'lyrics3') as $tag_name => $tag_key) {
				if (isset($this->info[$tag_key]['tag_offset_start'])) {
					$this->info['avdataend'] = min($this->info['avdataend'], $this->info[$tag_key]['tag_offset_start']);
				}
			}

			// ID3v2 detection (NOT parsing), even if ($this->option_tag_id3v2 == false) done to make fileformat easier
			if (!$this->option_tag_id3v2) {
				fseek($this->fp, 0);
				$header = fread($this->fp, 10);
				if ((substr($header, 0, 3) == 'ID3') && (strlen($header) == 10)) {
					$this->info['id3v2']['header']        = true;
					$this->info['id3v2']['majorversion']  = ord($header[3]);
					$this->info['id3v2']['minorversion']  = ord($header[4]);
					$this->info['avdataoffset']          += getid3_lib::BigEndian2Int(substr($header, 6, 4), 1) + 10; // length of ID3v2 tag in 10-byte header doesn't include 10-byte header length
				}
			}

			// read 32 kb file data
			fseek($this->fp, $this->info['avdataoffset']);
			$formattest = fread($this->fp, 32774);

			// determine format
			$determined_format = $this->GetFileFormat($formattest, ($original_filename ? $original_filename : $filename));

			// unable to determine file format
			if (!$determined_format) {
				fclose($this->fp);
				return $this->error('unable to determine file format');
			}

			// check for illegal ID3 tags
			if (isset($determined_format['fail_id3']) && (in_array('id3v1', $this->info['tags']) || in_array('id3v2', $this->info['tags']))) {
				if ($determined_format['fail_id3'] === 'ERROR') {
					fclose($this->fp);
					return $this->error('ID3 tags not allowed on this file type.');
				} elseif ($determined_format['fail_id3'] === 'WARNING') {
					$this->warning('ID3 tags not allowed on this file type.');
				}
			}

			// check for illegal APE tags
			if (isset($determined_format['fail_ape']) && in_array('ape', $this->info['tags'])) {
				if ($determined_format['fail_ape'] === 'ERROR') {
					fclose($this->fp);
					return $this->error('APE tags not allowed on this file type.');
				} elseif ($determined_format['fail_ape'] === 'WARNING') {
					$this->warning('APE tags not allowed on this file type.');
				}
			}

			// set mime type
			$this->info['mime_type'] = $determined_format['mime_type'];

			// supported format signature pattern detected, but module deleted
			if (!file_exists(GETID3_INCLUDEPATH.$determined_format['include'])) {
				fclose($this->fp);
				return $this->error('Format not supported, module "'.$determined_format['include'].'" was removed.');
			}

			// module requires mb_convert_encoding/iconv support
			// Check encoding/iconv support
			if (!empty($determined_format['iconv_req']) && !function_exists('mb_convert_encoding') && !function_exists('iconv') && !in_array($this->encoding, array('ISO-8859-1', 'UTF-8', 'UTF-16LE', 'UTF-16BE', 'UTF-16'))) {
				$errormessage = 'mb_convert_encoding() or iconv() support is required for this module ('.$determined_format['include'].') for encodings other than ISO-8859-1, UTF-8, UTF-16LE, UTF16-BE, UTF-16. ';
				if (GETID3_OS_ISWINDOWS) {
					$errormessage .= 'PHP does not have mb_convert_encoding() or iconv() support. Please enable php_mbstring.dll / php_iconv.dll in php.ini, and copy php_mbstring.dll / iconv.dll from c:/php/dlls to c:/windows/system32';
				} else {
					$errormessage .= 'PHP is not compiled with mb_convert_encoding() or iconv() support. Please recompile with the --enable-mbstring / --with-iconv switch';
				}
				return $this->error($errormessage);
			}

			// include module
			include_once(GETID3_INCLUDEPATH.$determined_format['include']);

			// instantiate module class
			$class_name = 'getid3_'.$determined_format['module'];
			if (!class_exists($class_name)) {
				return $this->error('Format not supported, module "'.$determined_format['include'].'" is corrupt.');
			}
			$class = new $class_name($this);
			$class->Analyze();
			unset($class);

			// close file
			fclose($this->fp);

			// process all tags - copy to 'tags' and convert charsets
			if ($this->option_tags_process) {
				$this->HandleAllTags();
			}

			// perform more calculations
			if ($this->option_extra_info) {
				$this->ChannelsBitratePlaytimeCalculations();
				$this->CalculateCompressionRatioVideo();
				$this->CalculateCompressionRatioAudio();
				$this->CalculateReplayGain();
				$this->ProcessAudioStreams();
			}

			// get the MD5 sum of the audio/video portion of the file - without ID3/APE/Lyrics3/etc header/footer tags
			if ($this->option_md5_data) {
				// do not calc md5_data if md5_data_source is present - set by flac only - future MPC/SV8 too
				if (!$this->option_md5_data_source || empty($this->info['md5_data_source'])) {
					$this->getHashdata('md5');
				}
			}

			// get the SHA1 sum of the audio/video portion of the file - without ID3/APE/Lyrics3/etc header/footer tags
			if ($this->option_sha1_data) {
				$this->getHashdata('sha1');
			}

			// remove undesired keys
			$this->CleanUp();

		} catch (Exception $e) {
			$this->error('Caught exception: '.$e->getMessage());
		}

		// return info array
		return $this->info;
	}


	/**
	 * Error handling.
	 *
	 * @param string $message
	 *
	 * @return array
	 */
	public function error($message) {
		$this->CleanUp();
		if (!isset($this->info['error'])) {
			$this->info['error'] = array();
		}
		$this->info['error'][] = $message;
		return $this->info;
	}


	/**
	 * Warning handling.
	 *
	 * @param string $message
	 *
	 * @return bool
	 */
	public function warning($message) {
		$this->info['warning'][] = $message;
		return true;
	}


	/**
	 * @return bool
	 */
	private function CleanUp() {

		// remove possible empty keys
		$AVpossibleEmptyKeys = array('dataformat', 'bits_per_sample', 'encoder_options', 'streams', 'bitrate');
		foreach ($AVpossibleEmptyKeys as $dummy => $key) {
			if (empty($this->info['audio'][$key]) && isset($this->info['audio'][$key])) {
				unset($this->info['audio'][$key]);
			}
			if (empty($this->info['video'][$key]) && isset($this->info['video'][$key])) {
				unset($this->info['video'][$key]);
			}
		}

		// remove empty root keys
		if (!empty($this->info)) {
			foreach ($this->info as $key => $value) {
				if (empty($this->info[$key]) && ($this->info[$key] !== 0) && ($this->info[$key] !== '0')) {
					unset($this->info[$key]);
				}
			}
		}

		// remove meaningless entries from unknown-format files
		if (empty($this->info['fileformat'])) {
			if (isset($this->info['avdataoffset'])) {
				unset($this->info['avdataoffset']);
			}
			if (isset($this->info['avdataend'])) {
				unset($this->info['avdataend']);
			}
		}

		// remove possible duplicated identical entries
		if (!empty($this->info['error'])) {
			$this->info['error'] = array_values(array_unique($this->info['error']));
		}
		if (!empty($this->info['warning'])) {
			$this->info['warning'] = array_values(array_unique($this->info['warning']));
		}

		// remove "global variable" type keys
		unset($this->info['php_memory_limit']);

		return true;
	}

	/**
	 * Return array containing information about all supported formats.
	 *
	 * @return array
	 */
	public function GetFileFormatArray() {
		static $format_info = array();
		if (empty($format_info)) {
			$format_info = array(

				// Audio formats

				// AC-3   - audio      - Dolby AC-3 / Dolby Digital
				'ac3'  => array(
							'pattern'   => '^\\x0B\\x77',
							'group'     => 'audio',
							'module'    => 'ac3',
							'mime_type' => 'audio/ac3',
						),

				// AAC  - audio       - Advanced Audio Coding (AAC) - ADIF format
				'adif' => array(
							'pattern'   => '^ADIF',
							'group'     => 'audio',
							'module'    => 'aac',
							'mime_type' => 'audio/aac',
							'fail_ape'  => 'WARNING',
						),

/*
				// AA   - audio       - Audible Audiobook
				'aa'   => array(
							'pattern'   => '^.{4}\\x57\\x90\\x75\\x36',
							'group'     => 'audio',
							'module'    => 'aa',
							'mime_type' => 'audio/audible',
						),
*/
				// AAC  - audio       - Advanced Audio Coding (AAC) - ADTS format (very similar to MP3)
				'adts' => array(
							'pattern'   => '^\\xFF[\\xF0-\\xF1\\xF8-\\xF9]',
							'group'     => 'audio',
							'module'    => 'aac',
							'mime_type' => 'audio/aac',
							'fail_ape'  => 'WARNING',
						),


				// AU   - audio       - NeXT/Sun AUdio (AU)
				'au'   => array(
							'pattern'   => '^\\.snd',
							'group'     => 'audio',
							'module'    => 'au',
							'mime_type' => 'audio/basic',
						),

				// AMR  - audio       - Adaptive Multi Rate
				'amr'  => array(
							'pattern'   => '^\\x23\\x21AMR\\x0A', // #!AMR[0A]
							'group'     => 'audio',
							'module'    => 'amr',
							'mime_type' => 'audio/amr',
						),

				// AVR  - audio       - Audio Visual Research
				'avr'  => array(
							'pattern'   => '^2BIT',
							'group'     => 'audio',
							'module'    => 'avr',
							'mime_type' => 'application/octet-stream',
						),

				// BONK - audio       - Bonk v0.9+
				'bonk' => array(
							'pattern'   => '^\\x00(BONK|INFO|META| ID3)',
							'group'     => 'audio',
							'module'    => 'bonk',
							'mime_type' => 'audio/xmms-bonk',
						),

				// DSF  - audio       - Direct Stream Digital (DSD) Storage Facility files (DSF) - https://en.wikipedia.org/wiki/Direct_Stream_Digital
				'dsf'  => array(
							'pattern'   => '^DSD ',  // including trailing space: 44 53 44 20
							'group'     => 'audio',
							'module'    => 'dsf',
							'mime_type' => 'audio/dsd',
						),

				// DSS  - audio       - Digital Speech Standard
				'dss'  => array(
							'pattern'   => '^[\\x02-\\x08]ds[s2]',
							'group'     => 'audio',
							'module'    => 'dss',
							'mime_type' => 'application/octet-stream',
						),

				// DTS  - audio       - Dolby Theatre System
				'dts'  => array(
							'pattern'   => '^\\x7F\\xFE\\x80\\x01',
							'group'     => 'audio',
							'module'    => 'dts',
							'mime_type' => 'audio/dts',
						),

				// FLAC - audio       - Free Lossless Audio Codec
				'flac' => array(
							'pattern'   => '^fLaC',
							'group'     => 'audio',
							'module'    => 'flac',
							'mime_type' => 'audio/flac',
						),

				// LA   - audio       - Lossless Audio (LA)
				'la'   => array(
							'pattern'   => '^LA0[2-4]',
							'group'     => 'audio',
							'module'    => 'la',
							'mime_type' => 'application/octet-stream',
						),

				// LPAC - audio       - Lossless Predictive Audio Compression (LPAC)
				'lpac' => array(
							'pattern'   => '^LPAC',
							'group'     => 'audio',
							'module'    => 'lpac',
							'mime_type' => 'application/octet-stream',
						),

				// MIDI - audio       - MIDI (Musical Instrument Digital Interface)
				'midi' => array(
							'pattern'   => '^MThd',
							'group'     => 'audio',
							'module'    => 'midi',
							'mime_type' => 'audio/midi',
						),

				// MAC  - audio       - Monkey's Audio Compressor
				'mac'  => array(
							'pattern'   => '^MAC ',
							'group'     => 'audio',
							'module'    => 'monkey',
							'mime_type' => 'audio/x-monkeys-audio',
						),

// has been known to produce false matches in random files (e.g. JPEGs), leave out until more precise matching available
//				// MOD  - audio       - MODule (assorted sub-formats)
//				'mod'  => array(
//							'pattern'   => '^.{1080}(M\\.K\\.|M!K!|FLT4|FLT8|[5-9]CHN|[1-3][0-9]CH)',
//							'group'     => 'audio',
//							'module'    => 'mod',
//							'option'    => 'mod',
//							'mime_type' => 'audio/mod',
//						),

				// MOD  - audio       - MODule (Impulse Tracker)
				'it'   => array(
							'pattern'   => '^IMPM',
							'group'     => 'audio',
							'module'    => 'mod',
							//'option'    => 'it',
							'mime_type' => 'audio/it',
						),

				// MOD  - audio       - MODule (eXtended Module, various sub-formats)
				'xm'   => array(
							'pattern'   => '^Extended Module',
							'group'     => 'audio',
							'module'    => 'mod',
							//'option'    => 'xm',
							'mime_type' => 'audio/xm',
						),

				// MOD  - audio       - MODule (ScreamTracker)
				's3m'  => array(
							'pattern'   => '^.{44}SCRM',
							'group'     => 'audio',
							'module'    => 'mod',
							//'option'    => 's3m',
							'mime_type' => 'audio/s3m',
						),

				// MPC  - audio       - Musepack / MPEGplus
				'mpc'  => array(
							'pattern'   => '^(MPCK|MP\\+|[\\x00\\x01\\x10\\x11\\x40\\x41\\x50\\x51\\x80\\x81\\x90\\x91\\xC0\\xC1\\xD0\\xD1][\\x20-\\x37][\\x00\\x20\\x40\\x60\\x80\\xA0\\xC0\\xE0])',
							'group'     => 'audio',
							'module'    => 'mpc',
							'mime_type' => 'audio/x-musepack',
						),

				// MP3  - audio       - MPEG-audio Layer 3 (very similar to AAC-ADTS)
				'mp3'  => array(
							'pattern'   => '^\\xFF[\\xE2-\\xE7\\xF2-\\xF7\\xFA-\\xFF][\\x00-\\x0B\\x10-\\x1B\\x20-\\x2B\\x30-\\x3B\\x40-\\x4B\\x50-\\x5B\\x60-\\x6B\\x70-\\x7B\\x80-\\x8B\\x90-\\x9B\\xA0-\\xAB\\xB0-\\xBB\\xC0-\\xCB\\xD0-\\xDB\\xE0-\\xEB\\xF0-\\xFB]',
							'group'     => 'audio',
							'module'    => 'mp3',
							'mime_type' => 'audio/mpeg',
						),

				// OFR  - audio       - OptimFROG
				'ofr'  => array(
							'pattern'   => '^(\\*RIFF|OFR)',
							'group'     => 'audio',
							'module'    => 'optimfrog',
							'mime_type' => 'application/octet-stream',
						),

				// RKAU - audio       - RKive AUdio compressor
				'rkau' => array(
							'pattern'   => '^RKA',
							'group'     => 'audio',
							'module'    => 'rkau',
							'mime_type' => 'application/octet-stream',
						),

				// SHN  - audio       - Shorten
				'shn'  => array(
							'pattern'   => '^ajkg',
							'group'     => 'audio',
							'module'    => 'shorten',
							'mime_type' => 'audio/xmms-shn',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),

				// TAK  - audio       - Tom's lossless Audio Kompressor
				'tak'  => array(
							'pattern'   => '^tBaK',
							'group'     => 'audio',
							'module'    => 'tak',
							'mime_type' => 'application/octet-stream',
						),

				// TTA  - audio       - TTA Lossless Audio Compressor (http://tta.corecodec.org)
				'tta'  => array(
							'pattern'   => '^TTA',  // could also be '^TTA(\\x01|\\x02|\\x03|2|1)'
							'group'     => 'audio',
							'module'    => 'tta',
							'mime_type' => 'application/octet-stream',
						),

				// VOC  - audio       - Creative Voice (VOC)
				'voc'  => array(
							'pattern'   => '^Creative Voice File',
							'group'     => 'audio',
							'module'    => 'voc',
							'mime_type' => 'audio/voc',
						),

				// VQF  - audio       - transform-domain weighted interleave Vector Quantization Format (VQF)
				'vqf'  => array(
							'pattern'   => '^TWIN',
							'group'     => 'audio',
							'module'    => 'vqf',
							'mime_type' => 'application/octet-stream',
						),

				// WV  - audio        - WavPack (v4.0+)
				'wv'   => array(
							'pattern'   => '^wvpk',
							'group'     => 'audio',
							'module'    => 'wavpack',
							'mime_type' => 'application/octet-stream',
						),


				// Audio-Video formats

				// ASF  - audio/video - Advanced Streaming Format, Windows Media Video, Windows Media Audio
				'asf'  => array(
							'pattern'   => '^\\x30\\x26\\xB2\\x75\\x8E\\x66\\xCF\\x11\\xA6\\xD9\\x00\\xAA\\x00\\x62\\xCE\\x6C',
							'group'     => 'audio-video',
							'module'    => 'asf',
							'mime_type' => 'video/x-ms-asf',
							'iconv_req' => false,
						),

				// BINK - audio/video - Bink / Smacker
				'bink' => array(
							'pattern'   => '^(BIK|SMK)',
							'group'     => 'audio-video',
							'module'    => 'bink',
							'mime_type' => 'application/octet-stream',
						),

				// FLV  - audio/video - FLash Video
				'flv' => array(
							'pattern'   => '^FLV[\\x01]',
							'group'     => 'audio-video',
							'module'    => 'flv',
							'mime_type' => 'video/x-flv',
						),

				// IVF - audio/video - IVF
				'ivf' => array(
							'pattern'   => '^DKIF',
							'group'     => 'audio-video',
							'module'    => 'ivf',
							'mime_type' => 'video/x-ivf',
						),

				// MKAV - audio/video - Mastroka
				'matroska' => array(
							'pattern'   => '^\\x1A\\x45\\xDF\\xA3',
							'group'     => 'audio-video',
							'module'    => 'matroska',
							'mime_type' => 'video/x-matroska', // may also be audio/x-matroska
						),

				// MPEG - audio/video - MPEG (Moving Pictures Experts Group)
				'mpeg' => array(
							'pattern'   => '^\\x00\\x00\\x01[\\xB3\\xBA]',
							'group'     => 'audio-video',
							'module'    => 'mpeg',
							'mime_type' => 'video/mpeg',
						),

				// NSV  - audio/video - Nullsoft Streaming Video (NSV)
				'nsv'  => array(
							'pattern'   => '^NSV[sf]',
							'group'     => 'audio-video',
							'module'    => 'nsv',
							'mime_type' => 'application/octet-stream',
						),

				// Ogg  - audio/video - Ogg (Ogg-Vorbis, Ogg-FLAC, Speex, Ogg-Theora(*), Ogg-Tarkin(*))
				'ogg'  => array(
							'pattern'   => '^OggS',
							'group'     => 'audio',
							'module'    => 'ogg',
							'mime_type' => 'application/ogg',
							'fail_id3'  => 'WARNING',
							'fail_ape'  => 'WARNING',
						),

				// QT   - audio/video - Quicktime
				'quicktime' => array(
							'pattern'   => '^.{4}(cmov|free|ftyp|mdat|moov|pnot|skip|wide)',
							'group'     => 'audio-video',
							'module'    => 'quicktime',
							'mime_type' => 'video/quicktime',
						),

				// RIFF - audio/video - Resource Interchange File Format (RIFF) / WAV / AVI / CD-audio / SDSS = renamed variant used by SmartSound QuickTracks (www.smartsound.com) / FORM = Audio Interchange File Format (AIFF)
				'riff' => array(
							'pattern'   => '^(RIFF|SDSS|FORM)',
							'group'     => 'audio-video',
							'module'    => 'riff',
							'mime_type' => 'audio/wav',
							'fail_ape'  => 'WARNING',
						),

				// Real - audio/video - RealAudio, RealVideo
				'real' => array(
							'pattern'   => '^\\.(RMF|ra)',
							'group'     => 'audio-video',
							'module'    => 'real',
							'mime_type' => 'audio/x-realaudio',
						),

				// SWF - audio/video - ShockWave Flash
				'swf' => array(
							'pattern'   => '^(F|C)WS',
							'group'     => 'audio-video',
							'module'    => 'swf',
							'mime_type' => 'application/x-shockwave-flash',
						),

				// TS - audio/video - MPEG-2 Transport Stream
				'ts' => array(
							'pattern'   => '^(\\x47.{187}){10,}', // packets are 188 bytes long and start with 0x47 "G".  Check for at least 10 packets matching this pattern
							'group'     => 'audio-video',
							'module'    => 'ts',
							'mime_type' => 'video/MP2T',
						),

				// WTV - audio/video - Windows Recorded TV Show
				'wtv' => array(
							'pattern'   => '^\\xB7\\xD8\\x00\\x20\\x37\\x49\\xDA\\x11\\xA6\\x4E\\x00\\x07\\xE9\\x5E\\xAD\\x8D',
							'group'     => 'audio-video',
							'module'    => 'wtv',
							'mime_type' => 'video/x-ms-wtv',
						),


				// Still-Image formats

				// BMP  - still image - Bitmap (Windows, OS/2; uncompressed, RLE8, RLE4)
				'bmp'  => array(
							'pattern'   => '^BM',
							'group'     => 'graphic',
							'module'    => 'bmp',
							'mime_type' => 'image/bmp',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),

				// GIF  - still image - Graphics Interchange Format
				'gif'  => array(
							'pattern'   => '^GIF',
							'group'     => 'graphic',
							'module'    => 'gif',
							'mime_type' => 'image/gif',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),

				// JPEG - still image - Joint Photographic Experts Group (JPEG)
				'jpg'  => array(
							'pattern'   => '^\\xFF\\xD8\\xFF',
							'group'     => 'graphic',
							'module'    => 'jpg',
							'mime_type' => 'image/jpeg',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),

				// PCD  - still image - Kodak Photo CD
				'pcd'  => array(
							'pattern'   => '^.{2048}PCD_IPI\\x00',
							'group'     => 'graphic',
							'module'    => 'pcd',
							'mime_type' => 'image/x-photo-cd',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),


				// PNG  - still image - Portable Network Graphics (PNG)
				'png'  => array(
							'pattern'   => '^\\x89\\x50\\x4E\\x47\\x0D\\x0A\\x1A\\x0A',
							'group'     => 'graphic',
							'module'    => 'png',
							'mime_type' => 'image/png',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),


				// SVG  - still image - Scalable Vector Graphics (SVG)
				'svg'  => array(
							'pattern'   => '(<!DOCTYPE svg PUBLIC |xmlns="http://www\\.w3\\.org/2000/svg")',
							'group'     => 'graphic',
							'module'    => 'svg',
							'mime_type' => 'image/svg+xml',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),


				// TIFF - still image - Tagged Information File Format (TIFF)
				'tiff' => array(
							'pattern'   => '^(II\\x2A\\x00|MM\\x00\\x2A)',
							'group'     => 'graphic',
							'module'    => 'tiff',
							'mime_type' => 'image/tiff',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),


				// EFAX - still image - eFax (TIFF derivative)
				'efax'  => array(
							'pattern'   => '^\\xDC\\xFE',
							'group'     => 'graphic',
							'module'    => 'efax',
							'mime_type' => 'image/efax',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),


				// Data formats

				// ISO  - data        - International Standards Organization (ISO) CD-ROM Image
				'iso'  => array(
							'pattern'   => '^.{32769}CD001',
							'group'     => 'misc',
							'module'    => 'iso',
							'mime_type' => 'application/octet-stream',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
							'iconv_req' => false,
						),

				// HPK  - data        - HPK compressed data
				'hpk'  => array(
							'pattern'   => '^BPUL',
							'group'     => 'archive',
							'module'    => 'hpk',
							'mime_type' => 'application/octet-stream',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),

				// RAR  - data        - RAR compressed data
				'rar'  => array(
							'pattern'   => '^Rar\\!',
							'group'     => 'archive',
							'module'    => 'rar',
							'mime_type' => 'application/vnd.rar',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),

				// SZIP - audio/data  - SZIP compressed data
				'szip' => array(
							'pattern'   => '^SZ\\x0A\\x04',
							'group'     => 'archive',
							'module'    => 'szip',
							'mime_type' => 'application/octet-stream',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),

				// TAR  - data        - TAR compressed data
				'tar'  => array(
							'pattern'   => '^.{100}[0-9\\x20]{7}\\x00[0-9\\x20]{7}\\x00[0-9\\x20]{7}\\x00[0-9\\x20\\x00]{12}[0-9\\x20\\x00]{12}',
							'group'     => 'archive',
							'module'    => 'tar',
							'mime_type' => 'application/x-tar',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),

				// GZIP  - data        - GZIP compressed data
				'gz'  => array(
							'pattern'   => '^\\x1F\\x8B\\x08',
							'group'     => 'archive',
							'module'    => 'gzip',
							'mime_type' => 'application/gzip',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),

				// ZIP  - data         - ZIP compressed data
				'zip'  => array(
							'pattern'   => '^PK\\x03\\x04',
							'group'     => 'archive',
							'module'    => 'zip',
							'mime_type' => 'application/zip',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),

				// XZ   - data         - XZ compressed data
				'xz'  => array(
							'pattern'   => '^\\xFD7zXZ\\x00',
							'group'     => 'archive',
							'module'    => 'xz',
							'mime_type' => 'application/x-xz',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),


				// Misc other formats

				// PAR2 - data        - Parity Volume Set Specification 2.0
				'par2' => array (
							'pattern'   => '^PAR2\\x00PKT',
							'group'     => 'misc',
							'module'    => 'par2',
							'mime_type' => 'application/octet-stream',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),

				// PDF  - data        - Portable Document Format
				'pdf'  => array(
							'pattern'   => '^\\x25PDF',
							'group'     => 'misc',
							'module'    => 'pdf',
							'mime_type' => 'application/pdf',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),

				// MSOFFICE  - data   - ZIP compressed data
				'msoffice' => array(
							'pattern'   => '^\\xD0\\xCF\\x11\\xE0\\xA1\\xB1\\x1A\\xE1', // D0CF11E == DOCFILE == Microsoft Office Document
							'group'     => 'misc',
							'module'    => 'msoffice',
							'mime_type' => 'application/octet-stream',
							'fail_id3'  => 'ERROR',
							'fail_ape'  => 'ERROR',
						),

				 // CUE  - data       - CUEsheet (index to single-file disc images)
				 'cue' => array(
							'pattern'   => '', // empty pattern means cannot be automatically detected, will fall through all other formats and match based on filename and very basic file contents
							'group'     => 'misc',
							'module'    => 'cue',
							'mime_type' => 'application/octet-stream',
						   ),

			);
		}

		return $format_info;
	}

	/**
	 * @param string $filedata
	 * @param string $filename
	 *
	 * @return mixed|false
	 */
	public function GetFileFormat(&$filedata, $filename='') {
		// this function will determine the format of a file based on usually
		// the first 2-4 bytes of the file (8 bytes for PNG, 16 bytes for JPG,
		// and in the case of ISO CD image, 6 bytes offset 32kb from the start
		// of the file).

		// Identify file format - loop through $format_info and detect with reg expr
		foreach ($this->GetFileFormatArray() as $format_name => $info) {
			// The /s switch on preg_match() forces preg_match() NOT to treat
			// newline (0x0A) characters as special chars but do a binary match
			if (!empty($info['pattern']) && preg_match('#'.$info['pattern'].'#s', $filedata)) {
				$info['include'] = 'module.'.$info['group'].'.'.$info['module'].'.php';
				return $info;
			}
		}


		if (preg_match('#\\.mp[123a]$#i', $filename)) {
			// Too many mp3 encoders on the market put garbage in front of mpeg files
			// use assume format on these if format detection failed
			$GetFileFormatArray = $this->GetFileFormatArray();
			$info = $GetFileFormatArray['mp3'];
			$info['include'] = 'module.'.$info['group'].'.'.$info['module'].'.php';
			return $info;
		} elseif (preg_match('#\\.cue$#i', $filename) && preg_match('#FILE "[^"]+" (BINARY|MOTOROLA|AIFF|WAVE|MP3)#', $filedata)) {
			// there's not really a useful consistent "magic" at the beginning of .cue files to identify them
			// so until I think of something better, just go by filename if all other format checks fail
			// and verify there's at least one instance of "TRACK xx AUDIO" in the file
			$GetFileFormatArray = $this->GetFileFormatArray();
			$info = $GetFileFormatArray['cue'];
			$info['include']   = 'module.'.$info['group'].'.'.$info['module'].'.php';
			return $info;
		}

		return false;
	}

	/**
	 * Converts array to $encoding charset from $this->encoding.
	 *
	 * @param array  $array
	 * @param string $encoding
	 */
	public function CharConvert(&$array, $encoding) {

		// identical encoding - end here
		if ($encoding == $this->encoding) {
			return;
		}

		// loop thru array
		foreach ($array as $key => $value) {

			// go recursive
			if (is_array($value)) {
				$this->CharConvert($array[$key], $encoding);
			}

			// convert string
			elseif (is_string($value)) {
				$array[$key] = trim(getid3_lib::iconv_fallback($encoding, $this->encoding, $value));
			}
		}
	}

	/**
	 * @return bool
	 */
	public function HandleAllTags() {

		// key name => array (tag name, character encoding)
		static $tags;
		if (empty($tags)) {
			$tags = array(
				'asf'       => array('asf'           , 'UTF-16LE'),
				'midi'      => array('midi'          , 'ISO-8859-1'),
				'nsv'       => array('nsv'           , 'ISO-8859-1'),
				'ogg'       => array('vorbiscomment' , 'UTF-8'),
				'png'       => array('png'           , 'UTF-8'),
				'tiff'      => array('tiff'          , 'ISO-8859-1'),
				'quicktime' => array('quicktime'     , 'UTF-8'),
				'real'      => array('real'          , 'ISO-8859-1'),
				'vqf'       => array('vqf'           , 'ISO-8859-1'),
				'zip'       => array('zip'           , 'ISO-8859-1'),
				'riff'      => array('riff'          , 'ISO-8859-1'),
				'lyrics3'   => array('lyrics3'       , 'ISO-8859-1'),
				'id3v1'     => array('id3v1'         , $this->encoding_id3v1),
				'id3v2'     => array('id3v2'         , 'UTF-8'), // not according to the specs (every frame can have a different encoding), but getID3() force-converts all encodings to UTF-8
				'ape'       => array('ape'           , 'UTF-8'),
				'cue'       => array('cue'           , 'ISO-8859-1'),
				'matroska'  => array('matroska'      , 'UTF-8'),
				'flac'      => array('vorbiscomment' , 'UTF-8'),
				'divxtag'   => array('divx'          , 'ISO-8859-1'),
				'iptc'      => array('iptc'          , 'ISO-8859-1'),
			);
		}

		// loop through comments array
		foreach ($tags as $comment_name => $tagname_encoding_array) {
			list($tag_name, $encoding) = $tagname_encoding_array;

			// fill in default encoding type if not already present
			if (isset($this->info[$comment_name]) && !isset($this->info[$comment_name]['encoding'])) {
				$this->info[$comment_name]['encoding'] = $encoding;
			}

			// copy comments if key name set
			if (!empty($this->info[$comment_name]['comments'])) {
				foreach ($this->info[$comment_name]['comments'] as $tag_key => $valuearray) {
					foreach ($valuearray as $key => $value) {
						if (is_string($value)) {
							$value = trim($value, " \r\n\t"); // do not trim nulls from $value!! Unicode characters will get mangled if trailing nulls are removed!
						}
						if ($value) {
							if (!is_numeric($key)) {
								$this->info['tags'][trim($tag_name)][trim($tag_key)][$key] = $value;
							} else {
								$this->info['tags'][trim($tag_name)][trim($tag_key)][]     = $value;
							}
						}
					}
					if ($tag_key == '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
						unset($this->info[$comment_name]['comments'][$tag_key]);
					}
				}

				if (!isset($this->info['tags'][$tag_name])) {
					// comments are set but contain nothing but empty strings, so skip
					continue;
				}

				$this->CharConvert($this->info['tags'][$tag_name], $this->info[$comment_name]['encoding']);           // only copy gets converted!

				if ($this->option_tags_html) {
					foreach ($this->info['tags'][$tag_name] as $tag_key => $valuearray) {
						if ($tag_key == 'picture') {
							// Do not to try to convert binary picture data to HTML
							// https://github.com/JamesHeinrich/getID3/issues/178
							continue;
						}
						$this->info['tags_html'][$tag_name][$tag_key] = getid3_lib::recursiveMultiByteCharString2HTML($valuearray, $this->info[$comment_name]['encoding']);
					}
				}

			}

		}

		// 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
		if (!empty($this->info['tags'])) {
			$unset_keys = array('tags', 'tags_html');
			foreach ($this->info['tags'] as $tagtype => $tagarray) {
				foreach ($tagarray as $tagname => $tagdata) {
					if ($tagname == 'picture') {
						foreach ($tagdata as $key => $tagarray) {
							$this->info['comments']['picture'][] = $tagarray;
							if (isset($tagarray['data']) && isset($tagarray['image_mime'])) {
								if (isset($this->info['tags'][$tagtype][$tagname][$key])) {
									unset($this->info['tags'][$tagtype][$tagname][$key]);
								}
								if (isset($this->info['tags_html'][$tagtype][$tagname][$key])) {
									unset($this->info['tags_html'][$tagtype][$tagname][$key]);
								}
							}
						}
					}
				}
				foreach ($unset_keys as $unset_key) {
					// remove possible empty keys from (e.g. [tags][id3v2][picture])
					if (empty($this->info[$unset_key][$tagtype]['picture'])) {
						unset($this->info[$unset_key][$tagtype]['picture']);
					}
					if (empty($this->info[$unset_key][$tagtype])) {
						unset($this->info[$unset_key][$tagtype]);
					}
					if (empty($this->info[$unset_key])) {
						unset($this->info[$unset_key]);
					}
				}
				// remove duplicate copy of picture data from (e.g. [id3v2][comments][picture])
				if (isset($this->info[$tagtype]['comments']['picture'])) {
					unset($this->info[$tagtype]['comments']['picture']);
				}
				if (empty($this->info[$tagtype]['comments'])) {
					unset($this->info[$tagtype]['comments']);
				}
				if (empty($this->info[$tagtype])) {
					unset($this->info[$tagtype]);
				}
			}
		}
		return true;
	}

	/**
	 * Calls getid3_lib::CopyTagsToComments() but passes in the option_tags_html setting from this instance of getID3
	 *
	 * @param array $ThisFileInfo
	 *
	 * @return bool
	 */
	public function CopyTagsToComments(&$ThisFileInfo) {
	    return getid3_lib::CopyTagsToComments($ThisFileInfo, $this->option_tags_html);
	}

	/**
	 * @param string $algorithm
	 *
	 * @return array|bool
	 */
	public function getHashdata($algorithm) {
		switch ($algorithm) {
			case 'md5':
			case 'sha1':
				break;

			default:
				return $this->error('bad algorithm "'.$algorithm.'" in getHashdata()');
		}

		if (!empty($this->info['fileformat']) && !empty($this->info['dataformat']) && ($this->info['fileformat'] == 'ogg') && ($this->info['audio']['dataformat'] == 'vorbis')) {

			// We cannot get an identical md5_data value for Ogg files where the comments
			// span more than 1 Ogg page (compared to the same audio data with smaller
			// comments) using the normal getID3() method of MD5'ing the data between the
			// end of the comments and the end of the file (minus any trailing tags),
			// because the page sequence numbers of the pages that the audio data is on
			// do not match. Under normal circumstances, where comments are smaller than
			// the nominal 4-8kB page size, then this is not a problem, but if there are
			// very large comments, the only way around it is to strip off the comment
			// tags with vorbiscomment and MD5 that file.
			// This procedure must be applied to ALL Ogg files, not just the ones with
			// comments larger than 1 page, because the below method simply MD5's the
			// whole file with the comments stripped, not just the portion after the
			// comments block (which is the standard getID3() method.

			// The above-mentioned problem of comments spanning multiple pages and changing
			// page sequence numbers likely happens for OggSpeex and OggFLAC as well, but
			// currently vorbiscomment only works on OggVorbis files.

			if (preg_match('#(1|ON)#i', ini_get('safe_mode'))) {

				$this->warning('Failed making system call to vorbiscomment.exe - '.$algorithm.'_data is incorrect - error returned: PHP running in Safe Mode (backtick operator not available)');
				$this->info[$algorithm.'_data'] = false;

			} else {

				// Prevent user from aborting script
				$old_abort = ignore_user_abort(true);

				// Create empty file
				$empty = tempnam(GETID3_TEMP_DIR, 'getID3');
				touch($empty);

				// Use vorbiscomment to make temp file without comments
				$temp = tempnam(GETID3_TEMP_DIR, 'getID3');
				$file = $this->info['filenamepath'];

				if (GETID3_OS_ISWINDOWS) {

					if (file_exists(GETID3_HELPERAPPSDIR.'vorbiscomment.exe')) {

						$commandline = '"'.GETID3_HELPERAPPSDIR.'vorbiscomment.exe" -w -c "'.$empty.'" "'.$file.'" "'.$temp.'"';
						$VorbisCommentError = `$commandline`;

					} else {

						$VorbisCommentError = 'vorbiscomment.exe not found in '.GETID3_HELPERAPPSDIR;

					}

				} else {

					$commandline = 'vorbiscomment -w -c '.escapeshellarg($empty).' '.escapeshellarg($file).' '.escapeshellarg($temp).' 2>&1';
					$VorbisCommentError = `$commandline`;

				}

				if (!empty($VorbisCommentError)) {

					$this->warning('Failed making system call to vorbiscomment(.exe) - '.$algorithm.'_data will be incorrect. If vorbiscomment is unavailable, please download from http://www.vorbis.com/download.psp and put in the getID3() directory. Error returned: '.$VorbisCommentError);
					$this->info[$algorithm.'_data'] = false;

				} else {

					// Get hash of newly created file
					switch ($algorithm) {
						case 'md5':
							$this->info[$algorithm.'_data'] = md5_file($temp);
							break;

						case 'sha1':
							$this->info[$algorithm.'_data'] = sha1_file($temp);
							break;
					}
				}

				// Clean up
				unlink($empty);
				unlink($temp);

				// Reset abort setting
				ignore_user_abort($old_abort);

			}

		} else {

			if (!empty($this->info['avdataoffset']) || (isset($this->info['avdataend']) && ($this->info['avdataend'] < $this->info['filesize']))) {

				// get hash from part of file
				$this->info[$algorithm.'_data'] = getid3_lib::hash_data($this->info['filenamepath'], $this->info['avdataoffset'], $this->info['avdataend'], $algorithm);

			} else {

				// get hash from whole file
				switch ($algorithm) {
					case 'md5':
						$this->info[$algorithm.'_data'] = md5_file($this->info['filenamepath']);
						break;

					case 'sha1':
						$this->info[$algorithm.'_data'] = sha1_file($this->info['filenamepath']);
						break;
				}
			}

		}
		return true;
	}

	public function ChannelsBitratePlaytimeCalculations() {

		// set channelmode on audio
		if (!empty($this->info['audio']['channelmode']) || !isset($this->info['audio']['channels'])) {
			// ignore
		} elseif ($this->info['audio']['channels'] == 1) {
			$this->info['audio']['channelmode'] = 'mono';
		} elseif ($this->info['audio']['channels'] == 2) {
			$this->info['audio']['channelmode'] = 'stereo';
		}

		// Calculate combined bitrate - audio + video
		$CombinedBitrate  = 0;
		$CombinedBitrate += (isset($this->info['audio']['bitrate']) ? $this->info['audio']['bitrate'] : 0);
		$CombinedBitrate += (isset($this->info['video']['bitrate']) ? $this->info['video']['bitrate'] : 0);
		if (($CombinedBitrate > 0) && empty($this->info['bitrate'])) {
			$this->info['bitrate'] = $CombinedBitrate;
		}
		//if ((isset($this->info['video']) && !isset($this->info['video']['bitrate'])) || (isset($this->info['audio']) && !isset($this->info['audio']['bitrate']))) {
		//	// for example, VBR MPEG video files cannot determine video bitrate:
		//	// should not set overall bitrate and playtime from audio bitrate only
		//	unset($this->info['bitrate']);
		//}

		// video bitrate undetermined, but calculable
		if (isset($this->info['video']['dataformat']) && $this->info['video']['dataformat'] && (!isset($this->info['video']['bitrate']) || ($this->info['video']['bitrate'] == 0))) {
			// if video bitrate not set
			if (isset($this->info['audio']['bitrate']) && ($this->info['audio']['bitrate'] > 0) && ($this->info['audio']['bitrate'] == $this->info['bitrate'])) {
				// AND if audio bitrate is set to same as overall bitrate
				if (isset($this->info['playtime_seconds']) && ($this->info['playtime_seconds'] > 0)) {
					// AND if playtime is set
					if (isset($this->info['avdataend']) && isset($this->info['avdataoffset'])) {
						// AND if AV data offset start/end is known
						// THEN we can calculate the video bitrate
						$this->info['bitrate'] = round((($this->info['avdataend'] - $this->info['avdataoffset']) * 8) / $this->info['playtime_seconds']);
						$this->info['video']['bitrate'] = $this->info['bitrate'] - $this->info['audio']['bitrate'];
					}
				}
			}
		}

		if ((!isset($this->info['playtime_seconds']) || ($this->info['playtime_seconds'] <= 0)) && !empty($this->info['bitrate'])) {
			$this->info['playtime_seconds'] = (($this->info['avdataend'] - $this->info['avdataoffset']) * 8) / $this->info['bitrate'];
		}

		if (!isset($this->info['bitrate']) && !empty($this->info['playtime_seconds'])) {
			$this->info['bitrate'] = (($this->info['avdataend'] - $this->info['avdataoffset']) * 8) / $this->info['playtime_seconds'];
		}
		if (isset($this->info['bitrate']) && empty($this->info['audio']['bitrate']) && empty($this->info['video']['bitrate'])) {
			if (isset($this->info['audio']['dataformat']) && empty($this->info['video']['resolution_x'])) {
				// audio only
				$this->info['audio']['bitrate'] = $this->info['bitrate'];
			} elseif (isset($this->info['video']['resolution_x']) && empty($this->info['audio']['dataformat'])) {
				// video only
				$this->info['video']['bitrate'] = $this->info['bitrate'];
			}
		}

		// Set playtime string
		if (!empty($this->info['playtime_seconds']) && empty($this->info['playtime_string'])) {
			$this->info['playtime_string'] = getid3_lib::PlaytimeString($this->info['playtime_seconds']);
		}
	}

	/**
	 * @return bool
	 */
	public function CalculateCompressionRatioVideo() {
		if (empty($this->info['video'])) {
			return false;
		}
		if (empty($this->info['video']['resolution_x']) || empty($this->info['video']['resolution_y'])) {
			return false;
		}
		if (empty($this->info['video']['bits_per_sample'])) {
			return false;
		}

		switch ($this->info['video']['dataformat']) {
			case 'bmp':
			case 'gif':
			case 'jpeg':
			case 'jpg':
			case 'png':
			case 'tiff':
				$FrameRate = 1;
				$PlaytimeSeconds = 1;
				$BitrateCompressed = $this->info['filesize'] * 8;
				break;

			default:
				if (!empty($this->info['video']['frame_rate'])) {
					$FrameRate = $this->info['video']['frame_rate'];
				} else {
					return false;
				}
				if (!empty($this->info['playtime_seconds'])) {
					$PlaytimeSeconds = $this->info['playtime_seconds'];
				} else {
					return false;
				}
				if (!empty($this->info['video']['bitrate'])) {
					$BitrateCompressed = $this->info['video']['bitrate'];
				} else {
					return false;
				}
				break;
		}
		$BitrateUncompressed = $this->info['video']['resolution_x'] * $this->info['video']['resolution_y'] * $this->info['video']['bits_per_sample'] * $FrameRate;

		$this->info['video']['compression_ratio'] = $BitrateCompressed / $BitrateUncompressed;
		return true;
	}

	/**
	 * @return bool
	 */
	public function CalculateCompressionRatioAudio() {
		if (empty($this->info['audio']['bitrate']) || empty($this->info['audio']['channels']) || empty($this->info['audio']['sample_rate']) || !is_numeric($this->info['audio']['sample_rate'])) {
			return false;
		}
		$this->info['audio']['compression_ratio'] = $this->info['audio']['bitrate'] / ($this->info['audio']['channels'] * $this->info['audio']['sample_rate'] * (!empty($this->info['audio']['bits_per_sample']) ? $this->info['audio']['bits_per_sample'] : 16));

		if (!empty($this->info['audio']['streams'])) {
			foreach ($this->info['audio']['streams'] as $streamnumber => $streamdata) {
				if (!empty($streamdata['bitrate']) && !empty($streamdata['channels']) && !empty($streamdata['sample_rate'])) {
					$this->info['audio']['streams'][$streamnumber]['compression_ratio'] = $streamdata['bitrate'] / ($streamdata['channels'] * $streamdata['sample_rate'] * (!empty($streamdata['bits_per_sample']) ? $streamdata['bits_per_sample'] : 16));
				}
			}
		}
		return true;
	}

	/**
	 * @return bool
	 */
	public function CalculateReplayGain() {
		if (isset($this->info['replay_gain'])) {
			if (!isset($this->info['replay_gain']['reference_volume'])) {
				$this->info['replay_gain']['reference_volume'] = 89.0;
			}
			if (isset($this->info['replay_gain']['track']['adjustment'])) {
				$this->info['replay_gain']['track']['volume'] = $this->info['replay_gain']['reference_volume'] - $this->info['replay_gain']['track']['adjustment'];
			}
			if (isset($this->info['replay_gain']['album']['adjustment'])) {
				$this->info['replay_gain']['album']['volume'] = $this->info['replay_gain']['reference_volume'] - $this->info['replay_gain']['album']['adjustment'];
			}

			if (isset($this->info['replay_gain']['track']['peak'])) {
				$this->info['replay_gain']['track']['max_noclip_gain'] = 0 - getid3_lib::RGADamplitude2dB($this->info['replay_gain']['track']['peak']);
			}
			if (isset($this->info['replay_gain']['album']['peak'])) {
				$this->info['replay_gain']['album']['max_noclip_gain'] = 0 - getid3_lib::RGADamplitude2dB($this->info['replay_gain']['album']['peak']);
			}
		}
		return true;
	}

	/**
	 * @return bool
	 */
	public function ProcessAudioStreams() {
		if (!empty($this->info['audio']['bitrate']) || !empty($this->info['audio']['channels']) || !empty($this->info['audio']['sample_rate'])) {
			if (!isset($this->info['audio']['streams'])) {
				foreach ($this->info['audio'] as $key => $value) {
					if ($key != 'streams') {
						$this->info['audio']['streams'][0][$key] = $value;
					}
				}
			}
		}
		return true;
	}

	/**
	 * @return string|bool
	 */
	public function getid3_tempnam() {
		return tempnam($this->tempdir, 'gI3');
	}

	/**
	 * @param string $name
	 *
	 * @return bool
	 *
	 * @throws getid3_exception
	 */
	public function include_module($name) {
		//if (!file_exists($this->include_path.'module.'.$name.'.php')) {
		if (!file_exists(GETID3_INCLUDEPATH.'module.'.$name.'.php')) {
			throw new getid3_exception('Required module.'.$name.'.php is missing.');
		}
		include_once(GETID3_INCLUDEPATH.'module.'.$name.'.php');
		return true;
	}

	/**
	 * @param string $filename
	 *
	 * @return bool
	 */
	public static function is_writable ($filename) {
		$ret = is_writable($filename);
		if (!$ret) {
			$perms = fileperms($filename);
			$ret = ($perms & 0x0080) || ($perms & 0x0010) || ($perms & 0x0002);
		}
		return $ret;
	}

}


abstract class getid3_handler
{

	/**
	* @var getID3
	*/
	protected $getid3;                       // pointer

	/**
	 * Analyzing filepointer or string.
	 *
	 * @var bool
	 */
	protected $data_string_flag     = false;

	/**
	 * String to analyze.
	 *
	 * @var string
	 */
	protected $data_string          = '';

	/**
	 * Seek position in string.
	 *
	 * @var int
	 */
	protected $data_string_position = 0;

	/**
	 * String length.
	 *
	 * @var int
	 */
	protected $data_string_length   = 0;

	/**
	 * @var string
	 */
	private $dependency_to;

	/**
	 * getid3_handler constructor.
	 *
	 * @param getID3 $getid3
	 * @param string $call_module
	 */
	public function __construct(getID3 $getid3, $call_module=null) {
		$this->getid3 = $getid3;

		if ($call_module) {
			$this->dependency_to = str_replace('getid3_', '', $call_module);
		}
	}

	/**
	 * Analyze from file pointer.
	 *
	 * @return bool
	 */
	abstract public function Analyze();

	/**
	 * Analyze from string instead.
	 *
	 * @param string $string
	 */
	public function AnalyzeString($string) {
		// Enter string mode
		$this->setStringMode($string);

		// Save info
		$saved_avdataoffset = $this->getid3->info['avdataoffset'];
		$saved_avdataend    = $this->getid3->info['avdataend'];
		$saved_filesize     = (isset($this->getid3->info['filesize']) ? $this->getid3->info['filesize'] : null); // may be not set if called as dependency without openfile() call

		// Reset some info
		$this->getid3->info['avdataoffset'] = 0;
		$this->getid3->info['avdataend']    = $this->getid3->info['filesize'] = $this->data_string_length;

		// Analyze
		$this->Analyze();

		// Restore some info
		$this->getid3->info['avdataoffset'] = $saved_avdataoffset;
		$this->getid3->info['avdataend']    = $saved_avdataend;
		$this->getid3->info['filesize']     = $saved_filesize;

		// Exit string mode
		$this->data_string_flag = false;
	}

	/**
	 * @param string $string
	 */
	public function setStringMode($string) {
		$this->data_string_flag   = true;
		$this->data_string        = $string;
		$this->data_string_length = strlen($string);
	}

	/**
	 * @return int|bool
	 */
	protected function ftell() {
		if ($this->data_string_flag) {
			return $this->data_string_position;
		}
		return ftell($this->getid3->fp);
	}

	/**
	 * @param int $bytes
	 *
	 * @return string|false
	 *
	 * @throws getid3_exception
	 */
	protected function fread($bytes) {
		if ($this->data_string_flag) {
			$this->data_string_position += $bytes;
			return substr($this->data_string, $this->data_string_position - $bytes, $bytes);
		}
		$pos = $this->ftell() + $bytes;
		if (!getid3_lib::intValueSupported($pos)) {
			throw new getid3_exception('cannot fread('.$bytes.' from '.$this->ftell().') because beyond PHP filesystem limit', 10);
		}

		//return fread($this->getid3->fp, $bytes);
		/*
		* https://www.getid3.org/phpBB3/viewtopic.php?t=1930
		* "I found out that the root cause for the problem was how getID3 uses the PHP system function fread().
		* It seems to assume that fread() would always return as many bytes as were requested.
		* However, according the PHP manual (http://php.net/manual/en/function.fread.php), this is the case only with regular local files, but not e.g. with Linux pipes.
		* The call may return only part of the requested data and a new call is needed to get more."
		*/
		$contents = '';
		do {
			//if (($this->getid3->memory_limit > 0) && ($bytes > $this->getid3->memory_limit)) {
			if (($this->getid3->memory_limit > 0) && (($bytes / $this->getid3->memory_limit) > 0.99)) { // enable a more-fuzzy match to prevent close misses generating errors like "PHP Fatal error: Allowed memory size of 33554432 bytes exhausted (tried to allocate 33554464 bytes)"
				throw new getid3_exception('cannot fread('.$bytes.' from '.$this->ftell().') that is more than available PHP memory ('.$this->getid3->memory_limit.')', 10);
			}
			$part = fread($this->getid3->fp, $bytes);
			$partLength  = strlen($part);
			$bytes      -= $partLength;
			$contents   .= $part;
		} while (($bytes > 0) && ($partLength > 0));
		return $contents;
	}

	/**
	 * @param int $bytes
	 * @param int $whence
	 *
	 * @return int
	 *
	 * @throws getid3_exception
	 */
	protected function fseek($bytes, $whence=SEEK_SET) {
		if ($this->data_string_flag) {
			switch ($whence) {
				case SEEK_SET:
					$this->data_string_position = $bytes;
					break;

				case SEEK_CUR:
					$this->data_string_position += $bytes;
					break;

				case SEEK_END:
					$this->data_string_position = $this->data_string_length + $bytes;
					break;
			}
			return 0;
		} else {
			$pos = $bytes;
			if ($whence == SEEK_CUR) {
				$pos = $this->ftell() + $bytes;
			} elseif ($whence == SEEK_END) {
				$pos = $this->getid3->info['filesize'] + $bytes;
			}
			if (!getid3_lib::intValueSupported($pos)) {
				throw new getid3_exception('cannot fseek('.$pos.') because beyond PHP filesystem limit', 10);
			}
		}
		return fseek($this->getid3->fp, $bytes, $whence);
	}

	/**
	 * @return bool
	 */
	protected function feof() {
		if ($this->data_string_flag) {
			return $this->data_string_position >= $this->data_string_length;
		}
		return feof($this->getid3->fp);
	}

	/**
	 * @param string $module
	 *
	 * @return bool
	 */
	final protected function isDependencyFor($module) {
		return $this->dependency_to == $module;
	}

	/**
	 * @param string $text
	 *
	 * @return bool
	 */
	protected function error($text) {
		$this->getid3->info['error'][] = $text;

		return false;
	}

	/**
	 * @param string $text
	 *
	 * @return bool
	 */
	protected function warning($text) {
		return $this->getid3->warning($text);
	}

	/**
	 * @param string $text
	 */
	protected function notice($text) {
		// does nothing for now
	}

	/**
	 * @param string $name
	 * @param int    $offset
	 * @param int    $length
	 * @param string $image_mime
	 *
	 * @return string|null
	 *
	 * @throws Exception
	 * @throws getid3_exception
	 */
	public function saveAttachment($name, $offset, $length, $image_mime=null) {
		try {

			// do not extract at all
			if ($this->getid3->option_save_attachments === getID3::ATTACHMENTS_NONE) {

				$attachment = null; // do not set any

			// extract to return array
			} elseif ($this->getid3->option_save_attachments === getID3::ATTACHMENTS_INLINE) {

				$this->fseek($offset);
				$attachment = $this->fread($length); // get whole data in one pass, till it is anyway stored in memory
				if ($attachment === false || strlen($attachment) != $length) {
					throw new Exception('failed to read attachment data');
				}

			// assume directory path is given
			} else {

				// set up destination path
				$dir = rtrim(str_replace(array('/', '\\'), DIRECTORY_SEPARATOR, $this->getid3->option_save_attachments), DIRECTORY_SEPARATOR);
				if (!is_dir($dir) || !getID3::is_writable($dir)) { // check supplied directory
					throw new Exception('supplied path ('.$dir.') does not exist, or is not writable');
				}
				$dest = $dir.DIRECTORY_SEPARATOR.$name.($image_mime ? '.'.getid3_lib::ImageExtFromMime($image_mime) : '');

				// create dest file
				if (($fp_dest = fopen($dest, 'wb')) == false) {
					throw new Exception('failed to create file '.$dest);
				}

				// copy data
				$this->fseek($offset);
				$buffersize = ($this->data_string_flag ? $length : $this->getid3->fread_buffer_size());
				$bytesleft = $length;
				while ($bytesleft > 0) {
					if (($buffer = $this->fread(min($buffersize, $bytesleft))) === false || ($byteswritten = fwrite($fp_dest, $buffer)) === false || ($byteswritten === 0)) {
						throw new Exception($buffer === false ? 'not enough data to read' : 'failed to write to destination file, may be not enough disk space');
					}
					$bytesleft -= $byteswritten;
				}

				fclose($fp_dest);
				$attachment = $dest;

			}

		} catch (Exception $e) {

			// close and remove dest file if created
			if (isset($fp_dest) && is_resource($fp_dest)) {
				fclose($fp_dest);
			}

			if (isset($dest) && file_exists($dest)) {
				unlink($dest);
			}

			// do not set any is case of error
			$attachment = null;
			$this->warning('Failed to extract attachment '.$name.': '.$e->getMessage());

		}

		// seek to the end of attachment
		$this->fseek($offset + $length);

		return $attachment;
	}

}


class getid3_exception extends Exception
{
	public $message;
}