<?php

/////////////////////////////////////////////////////////////////
/// getID3() by James Heinrich <info@getid3.org>               //
//  available at https://github.com/JamesHeinrich/getID3       //
//            or https://www.getid3.org                        //
//            or http://getid3.sourceforge.net                 //
//  see readme.txt for more details                            //
/////////////////////////////////////////////////////////////////
//                                                             //
// module.audio.ogg.php                                        //
// module for analyzing Ogg Vorbis, OggFLAC and Speex files    //
// dependencies: module.audio.flac.php                         //
//                                                            ///
/////////////////////////////////////////////////////////////////

if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers
	exit;
}
getid3_lib::IncludeDependency(GETID3_INCLUDEPATH.'module.audio.flac.php', __FILE__, true);

class getid3_ogg extends getid3_handler
{
	/**
	 * @link http://xiph.org/vorbis/doc/Vorbis_I_spec.html
	 *
	 * @return bool
	 */
	public function Analyze() {
		$info = &$this->getid3->info;

		$info['fileformat'] = 'ogg';

		// Warn about illegal tags - only vorbiscomments are allowed
		if (isset($info['id3v2'])) {
			$this->warning('Illegal ID3v2 tag present.');
		}
		if (isset($info['id3v1'])) {
			$this->warning('Illegal ID3v1 tag present.');
		}
		if (isset($info['ape'])) {
			$this->warning('Illegal APE tag present.');
		}

		// Page 1 - Stream Header

		$this->fseek($info['avdataoffset']);

		$oggpageinfo = $this->ParseOggPageHeader();
		$info['ogg']['pageheader'][$oggpageinfo['page_seqno']] = $oggpageinfo;

		if ($this->ftell() >= $this->getid3->fread_buffer_size()) {
			$this->error('Could not find start of Ogg page in the first '.$this->getid3->fread_buffer_size().' bytes (this might not be an Ogg-Vorbis file?)');
			unset($info['fileformat']);
			unset($info['ogg']);
			return false;
		}

		$filedata = $this->fread($oggpageinfo['page_length']);
		$filedataoffset = 0;

		if (substr($filedata, 0, 4) == 'fLaC') {

			$info['audio']['dataformat']   = 'flac';
			$info['audio']['bitrate_mode'] = 'vbr';
			$info['audio']['lossless']     = true;

		} elseif (substr($filedata, 1, 6) == 'vorbis') {

			$this->ParseVorbisPageHeader($filedata, $filedataoffset, $oggpageinfo);

		} elseif (substr($filedata, 0, 8) == 'OpusHead') {

			if ($this->ParseOpusPageHeader($filedata, $filedataoffset, $oggpageinfo) === false) {
				return false;
			}

		} elseif (substr($filedata, 0, 8) == 'Speex   ') {

			// http://www.speex.org/manual/node10.html

			$info['audio']['dataformat']   = 'speex';
			$info['mime_type']             = 'audio/speex';
			$info['audio']['bitrate_mode'] = 'abr';
			$info['audio']['lossless']     = false;

			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['speex_string']           =                              substr($filedata, $filedataoffset, 8); // hard-coded to 'Speex   '
			$filedataoffset += 8;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['speex_version']          =                              substr($filedata, $filedataoffset, 20);
			$filedataoffset += 20;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['speex_version_id']       = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
			$filedataoffset += 4;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['header_size']            = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
			$filedataoffset += 4;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['rate']                   = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
			$filedataoffset += 4;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['mode']                   = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
			$filedataoffset += 4;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['mode_bitstream_version'] = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
			$filedataoffset += 4;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['nb_channels']            = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
			$filedataoffset += 4;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['bitrate']                = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
			$filedataoffset += 4;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['framesize']              = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
			$filedataoffset += 4;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['vbr']                    = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
			$filedataoffset += 4;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['frames_per_packet']      = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
			$filedataoffset += 4;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['extra_headers']          = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
			$filedataoffset += 4;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['reserved1']              = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
			$filedataoffset += 4;
			$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['reserved2']              = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
			$filedataoffset += 4;

			$info['speex']['speex_version'] = trim($info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['speex_version']);
			$info['speex']['sample_rate']   = $info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['rate'];
			$info['speex']['channels']      = $info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['nb_channels'];
			$info['speex']['vbr']           = (bool) $info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['vbr'];
			$info['speex']['band_type']     = $this->SpeexBandModeLookup($info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['mode']);

			$info['audio']['sample_rate']   = $info['speex']['sample_rate'];
			$info['audio']['channels']      = $info['speex']['channels'];
			if ($info['speex']['vbr']) {
				$info['audio']['bitrate_mode'] = 'vbr';
			}

		} elseif (substr($filedata, 0, 7) == "\x80".'theora') {

			// http://www.theora.org/doc/Theora.pdf (section 6.2)

			$info['ogg']['pageheader']['theora']['theora_magic']             =                           substr($filedata, $filedataoffset,  7); // hard-coded to "\x80.'theora'
			$filedataoffset += 7;
			$info['ogg']['pageheader']['theora']['version_major']            = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  1));
			$filedataoffset += 1;
			$info['ogg']['pageheader']['theora']['version_minor']            = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  1));
			$filedataoffset += 1;
			$info['ogg']['pageheader']['theora']['version_revision']         = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  1));
			$filedataoffset += 1;
			$info['ogg']['pageheader']['theora']['frame_width_macroblocks']  = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  2));
			$filedataoffset += 2;
			$info['ogg']['pageheader']['theora']['frame_height_macroblocks'] = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  2));
			$filedataoffset += 2;
			$info['ogg']['pageheader']['theora']['resolution_x']             = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  3));
			$filedataoffset += 3;
			$info['ogg']['pageheader']['theora']['resolution_y']             = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  3));
			$filedataoffset += 3;
			$info['ogg']['pageheader']['theora']['picture_offset_x']         = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  1));
			$filedataoffset += 1;
			$info['ogg']['pageheader']['theora']['picture_offset_y']         = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  1));
			$filedataoffset += 1;
			$info['ogg']['pageheader']['theora']['frame_rate_numerator']     = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  4));
			$filedataoffset += 4;
			$info['ogg']['pageheader']['theora']['frame_rate_denominator']   = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  4));
			$filedataoffset += 4;
			$info['ogg']['pageheader']['theora']['pixel_aspect_numerator']   = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  3));
			$filedataoffset += 3;
			$info['ogg']['pageheader']['theora']['pixel_aspect_denominator'] = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  3));
			$filedataoffset += 3;
			$info['ogg']['pageheader']['theora']['color_space_id']           = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  1));
			$filedataoffset += 1;
			$info['ogg']['pageheader']['theora']['nominal_bitrate']          = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  3));
			$filedataoffset += 3;
			$info['ogg']['pageheader']['theora']['flags']                    = getid3_lib::BigEndian2Int(substr($filedata, $filedataoffset,  2));
			$filedataoffset += 2;

			$info['ogg']['pageheader']['theora']['quality']         = ($info['ogg']['pageheader']['theora']['flags'] & 0xFC00) >> 10;
			$info['ogg']['pageheader']['theora']['kfg_shift']       = ($info['ogg']['pageheader']['theora']['flags'] & 0x03E0) >>  5;
			$info['ogg']['pageheader']['theora']['pixel_format_id'] = ($info['ogg']['pageheader']['theora']['flags'] & 0x0018) >>  3;
			$info['ogg']['pageheader']['theora']['reserved']        = ($info['ogg']['pageheader']['theora']['flags'] & 0x0007) >>  0; // should be 0
			$info['ogg']['pageheader']['theora']['color_space']     = self::TheoraColorSpace($info['ogg']['pageheader']['theora']['color_space_id']);
			$info['ogg']['pageheader']['theora']['pixel_format']    = self::TheoraPixelFormat($info['ogg']['pageheader']['theora']['pixel_format_id']);

			$info['video']['dataformat']   = 'theora';
			$info['mime_type']             = 'video/ogg';
			//$info['audio']['bitrate_mode'] = 'abr';
			//$info['audio']['lossless']     = false;
			$info['video']['resolution_x'] = $info['ogg']['pageheader']['theora']['resolution_x'];
			$info['video']['resolution_y'] = $info['ogg']['pageheader']['theora']['resolution_y'];
			if ($info['ogg']['pageheader']['theora']['frame_rate_denominator'] > 0) {
				$info['video']['frame_rate'] = (float) $info['ogg']['pageheader']['theora']['frame_rate_numerator'] / $info['ogg']['pageheader']['theora']['frame_rate_denominator'];
			}
			if ($info['ogg']['pageheader']['theora']['pixel_aspect_denominator'] > 0) {
				$info['video']['pixel_aspect_ratio'] = (float) $info['ogg']['pageheader']['theora']['pixel_aspect_numerator'] / $info['ogg']['pageheader']['theora']['pixel_aspect_denominator'];
			}
			$this->warning('Ogg Theora (v3) not fully supported in this version of getID3 ['.$this->getid3->version().'] -- bitrate, playtime and all audio data are currently unavailable');

		} elseif (substr($filedata, 0, 8) == "fishead\x00") {

			// Ogg Skeleton version 3.0 Format Specification
			// http://xiph.org/ogg/doc/skeleton.html
			$filedataoffset += 8;
			$info['ogg']['skeleton']['fishead']['raw']['version_major']                = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  2));
			$filedataoffset += 2;
			$info['ogg']['skeleton']['fishead']['raw']['version_minor']                = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  2));
			$filedataoffset += 2;
			$info['ogg']['skeleton']['fishead']['raw']['presentationtime_numerator']   = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  8));
			$filedataoffset += 8;
			$info['ogg']['skeleton']['fishead']['raw']['presentationtime_denominator'] = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  8));
			$filedataoffset += 8;
			$info['ogg']['skeleton']['fishead']['raw']['basetime_numerator']           = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  8));
			$filedataoffset += 8;
			$info['ogg']['skeleton']['fishead']['raw']['basetime_denominator']         = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  8));
			$filedataoffset += 8;
			$info['ogg']['skeleton']['fishead']['raw']['utc']                          = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 20));
			$filedataoffset += 20;

			$info['ogg']['skeleton']['fishead']['version']          = $info['ogg']['skeleton']['fishead']['raw']['version_major'].'.'.$info['ogg']['skeleton']['fishead']['raw']['version_minor'];
			$info['ogg']['skeleton']['fishead']['presentationtime'] = $info['ogg']['skeleton']['fishead']['raw']['presentationtime_numerator'] / $info['ogg']['skeleton']['fishead']['raw']['presentationtime_denominator'];
			$info['ogg']['skeleton']['fishead']['basetime']         = $info['ogg']['skeleton']['fishead']['raw']['basetime_numerator']         / $info['ogg']['skeleton']['fishead']['raw']['basetime_denominator'];
			$info['ogg']['skeleton']['fishead']['utc']              = $info['ogg']['skeleton']['fishead']['raw']['utc'];

			$counter = 0;
			do {
				$oggpageinfo = $this->ParseOggPageHeader();
				$info['ogg']['pageheader'][$oggpageinfo['page_seqno'].'.'.$counter++] = $oggpageinfo;
				$filedata = $this->fread($oggpageinfo['page_length']);
				$this->fseek($oggpageinfo['page_end_offset']);

				if (substr($filedata, 0, 8) == "fisbone\x00") {

					$filedataoffset = 8;
					$info['ogg']['skeleton']['fisbone']['raw']['message_header_offset']   = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  4));
					$filedataoffset += 4;
					$info['ogg']['skeleton']['fisbone']['raw']['serial_number']           = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  4));
					$filedataoffset += 4;
					$info['ogg']['skeleton']['fisbone']['raw']['number_header_packets']   = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  4));
					$filedataoffset += 4;
					$info['ogg']['skeleton']['fisbone']['raw']['granulerate_numerator']   = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  8));
					$filedataoffset += 8;
					$info['ogg']['skeleton']['fisbone']['raw']['granulerate_denominator'] = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  8));
					$filedataoffset += 8;
					$info['ogg']['skeleton']['fisbone']['raw']['basegranule']             = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  8));
					$filedataoffset += 8;
					$info['ogg']['skeleton']['fisbone']['raw']['preroll']                 = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  4));
					$filedataoffset += 4;
					$info['ogg']['skeleton']['fisbone']['raw']['granuleshift']            = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  1));
					$filedataoffset += 1;
					$info['ogg']['skeleton']['fisbone']['raw']['padding']                 =                              substr($filedata, $filedataoffset,  3);
					$filedataoffset += 3;

				} elseif (substr($filedata, 1, 6) == 'theora') {

					$info['video']['dataformat'] = 'theora1';
					$this->error('Ogg Theora (v1) not correctly handled in this version of getID3 ['.$this->getid3->version().']');
					//break;

				} elseif (substr($filedata, 1, 6) == 'vorbis') {

					$this->ParseVorbisPageHeader($filedata, $filedataoffset, $oggpageinfo);

				} else {
					$this->error('unexpected');
					//break;
				}
			//} while ($oggpageinfo['page_seqno'] == 0);
			} while (($oggpageinfo['page_seqno'] == 0) && (substr($filedata, 0, 8) != "fisbone\x00"));

			$this->fseek($oggpageinfo['page_start_offset']);

			$this->error('Ogg Skeleton not correctly handled in this version of getID3 ['.$this->getid3->version().']');
			//return false;

		} elseif (substr($filedata, 0, 5) == "\x7F".'FLAC') {
			// https://xiph.org/flac/ogg_mapping.html

			$info['audio']['dataformat']   = 'flac';
			$info['audio']['bitrate_mode'] = 'vbr';
			$info['audio']['lossless']     = true;

			$info['ogg']['flac']['header']['version_major']  =                         ord(substr($filedata,  5, 1));
			$info['ogg']['flac']['header']['version_minor']  =                         ord(substr($filedata,  6, 1));
			$info['ogg']['flac']['header']['header_packets'] =   getid3_lib::BigEndian2Int(substr($filedata,  7, 2)) + 1; // "A two-byte, big-endian binary number signifying the number of header (non-audio) packets, not including this one. This number may be zero (0x0000) to signify 'unknown' but be aware that some decoders may not be able to handle such streams."
			$info['ogg']['flac']['header']['magic']          =                             substr($filedata,  9, 4);
			if ($info['ogg']['flac']['header']['magic'] != 'fLaC') {
				$this->error('Ogg-FLAC expecting "fLaC", found "'.$info['ogg']['flac']['header']['magic'].'" ('.trim(getid3_lib::PrintHexBytes($info['ogg']['flac']['header']['magic'])).')');
				return false;
			}
			$info['ogg']['flac']['header']['STREAMINFO_bytes'] = getid3_lib::BigEndian2Int(substr($filedata, 13, 4));
			$info['flac']['STREAMINFO'] = getid3_flac::parseSTREAMINFOdata(substr($filedata, 17, 34));
			if (!empty($info['flac']['STREAMINFO']['sample_rate'])) {
				$info['audio']['bitrate_mode']    = 'vbr';
				$info['audio']['sample_rate']     = $info['flac']['STREAMINFO']['sample_rate'];
				$info['audio']['channels']        = $info['flac']['STREAMINFO']['channels'];
				$info['audio']['bits_per_sample'] = $info['flac']['STREAMINFO']['bits_per_sample'];
				$info['playtime_seconds']         = $info['flac']['STREAMINFO']['samples_stream'] / $info['flac']['STREAMINFO']['sample_rate'];
			}

		} else {

			$this->error('Expecting one of "vorbis", "Speex", "OpusHead", "vorbis", "fishhead", "theora", "fLaC" identifier strings, found "'.substr($filedata, 0, 8).'"');
			unset($info['ogg']);
			unset($info['mime_type']);
			return false;

		}

		// Page 2 - Comment Header
		$oggpageinfo = $this->ParseOggPageHeader();
		$info['ogg']['pageheader'][$oggpageinfo['page_seqno']] = $oggpageinfo;

		switch ($info['audio']['dataformat']) {
			case 'vorbis':
				$filedata = $this->fread($info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['page_length']);
				$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['packet_type'] = getid3_lib::LittleEndian2Int(substr($filedata, 0, 1));
				$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['stream_type'] =                              substr($filedata, 1, 6); // hard-coded to 'vorbis'

				$this->ParseVorbisComments();
				break;

			case 'flac':
				$flac = new getid3_flac($this->getid3);
				if (!$flac->parseMETAdata()) {
					$this->error('Failed to parse FLAC headers');
					return false;
				}
				unset($flac);
				break;

			case 'speex':
				$this->fseek($info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['page_length'], SEEK_CUR);
				$this->ParseVorbisComments();
				break;

			case 'opus':
				$filedata = $this->fread($info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['page_length']);
				$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['stream_type'] = substr($filedata, 0, 8); // hard-coded to 'OpusTags'
				if(substr($filedata, 0, 8)  != 'OpusTags') {
					$this->error('Expected "OpusTags" as header but got "'.substr($filedata, 0, 8).'"');
					return false;
				}

				$this->ParseVorbisComments();
				break;

		}

		// Last Page - Number of Samples
		if (!getid3_lib::intValueSupported($info['avdataend'])) {

			$this->warning('Unable to parse Ogg end chunk file (PHP does not support file operations beyond '.round(PHP_INT_MAX / 1073741824).'GB)');

		} else {

			$this->fseek(max($info['avdataend'] - $this->getid3->fread_buffer_size(), 0));
			$LastChunkOfOgg = strrev($this->fread($this->getid3->fread_buffer_size()));
			if ($LastOggSpostion = strpos($LastChunkOfOgg, 'SggO')) {
				$this->fseek($info['avdataend'] - ($LastOggSpostion + strlen('SggO')));
				$info['avdataend'] = $this->ftell();
				$info['ogg']['pageheader']['eos'] = $this->ParseOggPageHeader();
				$info['ogg']['samples']   = $info['ogg']['pageheader']['eos']['pcm_abs_position'];
				if ($info['ogg']['samples'] == 0) {
					$this->error('Corrupt Ogg file: eos.number of samples == zero');
					return false;
				}
				if (!empty($info['audio']['sample_rate'])) {
					$info['ogg']['bitrate_average'] = (($info['avdataend'] - $info['avdataoffset']) * 8) / ($info['ogg']['samples'] / $info['audio']['sample_rate']);
				}
			}

		}

		if (!empty($info['ogg']['bitrate_average'])) {
			$info['audio']['bitrate'] = $info['ogg']['bitrate_average'];
		} elseif (!empty($info['ogg']['bitrate_nominal'])) {
			$info['audio']['bitrate'] = $info['ogg']['bitrate_nominal'];
		} elseif (!empty($info['ogg']['bitrate_min']) && !empty($info['ogg']['bitrate_max'])) {
			$info['audio']['bitrate'] = ($info['ogg']['bitrate_min'] + $info['ogg']['bitrate_max']) / 2;
		}
		if (isset($info['audio']['bitrate']) && !isset($info['playtime_seconds'])) {
			if ($info['audio']['bitrate'] == 0) {
				$this->error('Corrupt Ogg file: bitrate_audio == zero');
				return false;
			}
			$info['playtime_seconds'] = (float) ((($info['avdataend'] - $info['avdataoffset']) * 8) / $info['audio']['bitrate']);
		}

		if (isset($info['ogg']['vendor'])) {
			$info['audio']['encoder'] = preg_replace('/^Encoded with /', '', $info['ogg']['vendor']);

			// Vorbis only
			if ($info['audio']['dataformat'] == 'vorbis') {

				// Vorbis 1.0 starts with Xiph.Org
				if  (preg_match('/^Xiph.Org/', $info['audio']['encoder'])) {

					if ($info['audio']['bitrate_mode'] == 'abr') {

						// Set -b 128 on abr files
						$info['audio']['encoder_options'] = '-b '.round($info['ogg']['bitrate_nominal'] / 1000);

					} elseif (($info['audio']['bitrate_mode'] == 'vbr') && ($info['audio']['channels'] == 2) && ($info['audio']['sample_rate'] >= 44100) && ($info['audio']['sample_rate'] <= 48000)) {
						// Set -q N on vbr files
						$info['audio']['encoder_options'] = '-q '.$this->get_quality_from_nominal_bitrate($info['ogg']['bitrate_nominal']);

					}
				}

				if (empty($info['audio']['encoder_options']) && !empty($info['ogg']['bitrate_nominal'])) {
					$info['audio']['encoder_options'] = 'Nominal bitrate: '.intval(round($info['ogg']['bitrate_nominal'] / 1000)).'kbps';
				}
			}
		}

		return true;
	}

	/**
	 * @param string $filedata
	 * @param int    $filedataoffset
	 * @param array  $oggpageinfo
	 *
	 * @return bool
	 */
	public function ParseVorbisPageHeader(&$filedata, &$filedataoffset, &$oggpageinfo) {
		$info = &$this->getid3->info;
		$info['audio']['dataformat'] = 'vorbis';
		$info['audio']['lossless']   = false;

		$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['packet_type'] = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 1));
		$filedataoffset += 1;
		$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['stream_type'] = substr($filedata, $filedataoffset, 6); // hard-coded to 'vorbis'
		$filedataoffset += 6;
		$info['ogg']['bitstreamversion'] = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
		$filedataoffset += 4;
		$info['ogg']['numberofchannels'] = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 1));
		$filedataoffset += 1;
		$info['audio']['channels']       = $info['ogg']['numberofchannels'];
		$info['ogg']['samplerate']       = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
		$filedataoffset += 4;
		if ($info['ogg']['samplerate'] == 0) {
			$this->error('Corrupt Ogg file: sample rate == zero');
			return false;
		}
		$info['audio']['sample_rate']    = $info['ogg']['samplerate'];
		$info['ogg']['samples']          = 0; // filled in later
		$info['ogg']['bitrate_average']  = 0; // filled in later
		$info['ogg']['bitrate_max']      = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
		$filedataoffset += 4;
		$info['ogg']['bitrate_nominal']  = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
		$filedataoffset += 4;
		$info['ogg']['bitrate_min']      = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
		$filedataoffset += 4;
		$info['ogg']['blocksize_small']  = pow(2,  getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 1)) & 0x0F);
		$info['ogg']['blocksize_large']  = pow(2, (getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 1)) & 0xF0) >> 4);
		$info['ogg']['stop_bit']         = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 1)); // must be 1, marks end of packet

		$info['audio']['bitrate_mode'] = 'vbr'; // overridden if actually abr
		if ($info['ogg']['bitrate_max'] == 0xFFFFFFFF) {
			unset($info['ogg']['bitrate_max']);
			$info['audio']['bitrate_mode'] = 'abr';
		}
		if ($info['ogg']['bitrate_nominal'] == 0xFFFFFFFF) {
			unset($info['ogg']['bitrate_nominal']);
		}
		if ($info['ogg']['bitrate_min'] == 0xFFFFFFFF) {
			unset($info['ogg']['bitrate_min']);
			$info['audio']['bitrate_mode'] = 'abr';
		}
		return true;
	}

	/**
	 * @link http://tools.ietf.org/html/draft-ietf-codec-oggopus-03
	 *
	 * @param string $filedata
	 * @param int    $filedataoffset
	 * @param array  $oggpageinfo
	 *
	 * @return bool
	 */
	public function ParseOpusPageHeader(&$filedata, &$filedataoffset, &$oggpageinfo) {
		$info = &$this->getid3->info;
		$info['audio']['dataformat']   = 'opus';
		$info['mime_type']             = 'audio/ogg; codecs=opus';

		/** @todo find a usable way to detect abr (vbr that is padded to be abr) */
		$info['audio']['bitrate_mode'] = 'vbr';

		$info['audio']['lossless']     = false;

		$info['ogg']['pageheader']['opus']['opus_magic'] = substr($filedata, $filedataoffset, 8); // hard-coded to 'OpusHead'
		$filedataoffset += 8;
		$info['ogg']['pageheader']['opus']['version']    = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  1));
		$filedataoffset += 1;

		if ($info['ogg']['pageheader']['opus']['version'] < 1 || $info['ogg']['pageheader']['opus']['version'] > 15) {
			$this->error('Unknown opus version number (only accepting 1-15)');
			return false;
		}

		$info['ogg']['pageheader']['opus']['out_channel_count'] = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  1));
		$filedataoffset += 1;

		if ($info['ogg']['pageheader']['opus']['out_channel_count'] == 0) {
			$this->error('Invalid channel count in opus header (must not be zero)');
			return false;
		}

		$info['ogg']['pageheader']['opus']['pre_skip'] = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  2));
		$filedataoffset += 2;

		$info['ogg']['pageheader']['opus']['input_sample_rate'] = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  4));
		$filedataoffset += 4;

		//$info['ogg']['pageheader']['opus']['output_gain'] = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  2));
		//$filedataoffset += 2;

		//$info['ogg']['pageheader']['opus']['channel_mapping_family'] = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset,  1));
		//$filedataoffset += 1;

		$info['opus']['opus_version']       = $info['ogg']['pageheader']['opus']['version'];
		$info['opus']['sample_rate_input']  = $info['ogg']['pageheader']['opus']['input_sample_rate'];
		$info['opus']['out_channel_count']  = $info['ogg']['pageheader']['opus']['out_channel_count'];

		$info['audio']['channels']          = $info['opus']['out_channel_count'];
		$info['audio']['sample_rate_input'] = $info['opus']['sample_rate_input'];
		$info['audio']['sample_rate']       = 48000; // "All Opus audio is coded at 48 kHz, and should also be decoded at 48 kHz for playback (unless the target hardware does not support this sampling rate). However, this field may be used to resample the audio back to the original sampling rate, for example, when saving the output to a file." -- https://mf4.xiph.org/jenkins/view/opus/job/opusfile-unix/ws/doc/html/structOpusHead.html
		return true;
	}

	/**
	 * @return array|false
	 */
	public function ParseOggPageHeader() {
		// http://xiph.org/ogg/vorbis/doc/framing.html
		$oggheader['page_start_offset'] = $this->ftell(); // where we started from in the file

		$filedata = $this->fread($this->getid3->fread_buffer_size());
		$filedataoffset = 0;
		while ((substr($filedata, $filedataoffset++, 4) != 'OggS')) {
			if (($this->ftell() - $oggheader['page_start_offset']) >= $this->getid3->fread_buffer_size()) {
				// should be found before here
				return false;
			}
			if ((($filedataoffset + 28) > strlen($filedata)) || (strlen($filedata) < 28)) {
				if ($this->feof() || (($filedata .= $this->fread($this->getid3->fread_buffer_size())) === '')) {
					// get some more data, unless eof, in which case fail
					return false;
				}
			}
		}
		$filedataoffset += strlen('OggS') - 1; // page, delimited by 'OggS'

		$oggheader['stream_structver']  = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 1));
		$filedataoffset += 1;
		$oggheader['flags_raw']         = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 1));
		$filedataoffset += 1;
		$oggheader['flags']['fresh']    = (bool) ($oggheader['flags_raw'] & 0x01); // fresh packet
		$oggheader['flags']['bos']      = (bool) ($oggheader['flags_raw'] & 0x02); // first page of logical bitstream (bos)
		$oggheader['flags']['eos']      = (bool) ($oggheader['flags_raw'] & 0x04); // last page of logical bitstream (eos)

		$oggheader['pcm_abs_position']  = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 8));
		$filedataoffset += 8;
		$oggheader['stream_serialno']   = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
		$filedataoffset += 4;
		$oggheader['page_seqno']        = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
		$filedataoffset += 4;
		$oggheader['page_checksum']     = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 4));
		$filedataoffset += 4;
		$oggheader['page_segments']     = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 1));
		$filedataoffset += 1;
		$oggheader['page_length'] = 0;
		for ($i = 0; $i < $oggheader['page_segments']; $i++) {
			$oggheader['segment_table'][$i] = getid3_lib::LittleEndian2Int(substr($filedata, $filedataoffset, 1));
			$filedataoffset += 1;
			$oggheader['page_length'] += $oggheader['segment_table'][$i];
		}
		$oggheader['header_end_offset'] = $oggheader['page_start_offset'] + $filedataoffset;
		$oggheader['page_end_offset']   = $oggheader['header_end_offset'] + $oggheader['page_length'];
		$this->fseek($oggheader['header_end_offset']);

		return $oggheader;
	}

	/**
	 * @link http://xiph.org/vorbis/doc/Vorbis_I_spec.html#x1-810005
	 *
	 * @return bool
	 */
	public function ParseVorbisComments() {
		$info = &$this->getid3->info;

		$OriginalOffset = $this->ftell();
		$commentdata = null;
		$commentdataoffset = 0;
		$VorbisCommentPage = 1;
		$CommentStartOffset = 0;

		switch ($info['audio']['dataformat']) {
			case 'vorbis':
			case 'speex':
			case 'opus':
				$CommentStartOffset = $info['ogg']['pageheader'][$VorbisCommentPage]['page_start_offset'];  // Second Ogg page, after header block
				$this->fseek($CommentStartOffset);
				$commentdataoffset = 27 + $info['ogg']['pageheader'][$VorbisCommentPage]['page_segments'];
				$commentdata = $this->fread(self::OggPageSegmentLength($info['ogg']['pageheader'][$VorbisCommentPage], 1) + $commentdataoffset);

				if ($info['audio']['dataformat'] == 'vorbis') {
					$commentdataoffset += (strlen('vorbis') + 1);
				}
				else if ($info['audio']['dataformat'] == 'opus') {
					$commentdataoffset += strlen('OpusTags');
				}

				break;

			case 'flac':
				$CommentStartOffset = $info['flac']['VORBIS_COMMENT']['raw']['offset'] + 4;
				$this->fseek($CommentStartOffset);
				$commentdata = $this->fread($info['flac']['VORBIS_COMMENT']['raw']['block_length']);
				break;

			default:
				return false;
		}

		$VendorSize = getid3_lib::LittleEndian2Int(substr($commentdata, $commentdataoffset, 4));
		$commentdataoffset += 4;

		$info['ogg']['vendor'] = substr($commentdata, $commentdataoffset, $VendorSize);
		$commentdataoffset += $VendorSize;

		$CommentsCount = getid3_lib::LittleEndian2Int(substr($commentdata, $commentdataoffset, 4));
		$commentdataoffset += 4;
		$info['avdataoffset'] = $CommentStartOffset + $commentdataoffset;

		$basicfields = array('TITLE', 'ARTIST', 'ALBUM', 'TRACKNUMBER', 'GENRE', 'DATE', 'DESCRIPTION', 'COMMENT');
		$ThisFileInfo_ogg_comments_raw = &$info['ogg']['comments_raw'];
		for ($i = 0; $i < $CommentsCount; $i++) {

			if ($i >= 10000) {
				// https://github.com/owncloud/music/issues/212#issuecomment-43082336
				$this->warning('Unexpectedly large number ('.$CommentsCount.') of Ogg comments - breaking after reading '.$i.' comments');
				break;
			}

			$ThisFileInfo_ogg_comments_raw[$i]['dataoffset'] = $CommentStartOffset + $commentdataoffset;

			if ($this->ftell() < ($ThisFileInfo_ogg_comments_raw[$i]['dataoffset'] + 4)) {
				if ($oggpageinfo = $this->ParseOggPageHeader()) {
					$info['ogg']['pageheader'][$oggpageinfo['page_seqno']] = $oggpageinfo;

					$VorbisCommentPage++;

					// First, save what we haven't read yet
					$AsYetUnusedData = substr($commentdata, $commentdataoffset);

					// Then take that data off the end
					$commentdata     = substr($commentdata, 0, $commentdataoffset);

					// Add [headerlength] bytes of dummy data for the Ogg Page Header, just to keep absolute offsets correct
					$commentdata .= str_repeat("\x00", 27 + $info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['page_segments']);
					$commentdataoffset += (27 + $info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['page_segments']);

					// Finally, stick the unused data back on the end
					$commentdata .= $AsYetUnusedData;

					//$commentdata .= $this->fread($info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['page_length']);
					$commentdata .= $this->fread($this->OggPageSegmentLength($info['ogg']['pageheader'][$VorbisCommentPage], 1));
				}

			}
			$ThisFileInfo_ogg_comments_raw[$i]['size'] = getid3_lib::LittleEndian2Int(substr($commentdata, $commentdataoffset, 4));

			// replace avdataoffset with position just after the last vorbiscomment
			$info['avdataoffset'] = $ThisFileInfo_ogg_comments_raw[$i]['dataoffset'] + $ThisFileInfo_ogg_comments_raw[$i]['size'] + 4;

			$commentdataoffset += 4;
			while ((strlen($commentdata) - $commentdataoffset) < $ThisFileInfo_ogg_comments_raw[$i]['size']) {
				if (($ThisFileInfo_ogg_comments_raw[$i]['size'] > $info['avdataend']) || ($ThisFileInfo_ogg_comments_raw[$i]['size'] < 0)) {
					$this->warning('Invalid Ogg comment size (comment #'.$i.', claims to be '.number_format($ThisFileInfo_ogg_comments_raw[$i]['size']).' bytes) - aborting reading comments');
					break 2;
				}

				$VorbisCommentPage++;

				$oggpageinfo = $this->ParseOggPageHeader();
				$info['ogg']['pageheader'][$oggpageinfo['page_seqno']] = $oggpageinfo;

				// First, save what we haven't read yet
				$AsYetUnusedData = substr($commentdata, $commentdataoffset);

				// Then take that data off the end
				$commentdata     = substr($commentdata, 0, $commentdataoffset);

				// Add [headerlength] bytes of dummy data for the Ogg Page Header, just to keep absolute offsets correct
				$commentdata .= str_repeat("\x00", 27 + $info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['page_segments']);
				$commentdataoffset += (27 + $info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['page_segments']);

				// Finally, stick the unused data back on the end
				$commentdata .= $AsYetUnusedData;

				//$commentdata .= $this->fread($info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['page_length']);
				if (!isset($info['ogg']['pageheader'][$VorbisCommentPage])) {
					$this->warning('undefined Vorbis Comment page "'.$VorbisCommentPage.'" at offset '.$this->ftell());
					break;
				}
				$readlength = self::OggPageSegmentLength($info['ogg']['pageheader'][$VorbisCommentPage], 1);
				if ($readlength <= 0) {
					$this->warning('invalid length Vorbis Comment page "'.$VorbisCommentPage.'" at offset '.$this->ftell());
					break;
				}
				$commentdata .= $this->fread($readlength);

				//$filebaseoffset += $oggpageinfo['header_end_offset'] - $oggpageinfo['page_start_offset'];
			}
			$ThisFileInfo_ogg_comments_raw[$i]['offset'] = $commentdataoffset;
			$commentstring = substr($commentdata, $commentdataoffset, $ThisFileInfo_ogg_comments_raw[$i]['size']);
			$commentdataoffset += $ThisFileInfo_ogg_comments_raw[$i]['size'];

			if (!$commentstring) {

				// no comment?
				$this->warning('Blank Ogg comment ['.$i.']');

			} elseif (strstr($commentstring, '=')) {

				$commentexploded = explode('=', $commentstring, 2);
				$ThisFileInfo_ogg_comments_raw[$i]['key']   = strtoupper($commentexploded[0]);
				$ThisFileInfo_ogg_comments_raw[$i]['value'] = (isset($commentexploded[1]) ? $commentexploded[1] : '');

				if ($ThisFileInfo_ogg_comments_raw[$i]['key'] == 'METADATA_BLOCK_PICTURE') {

					// http://wiki.xiph.org/VorbisComment#METADATA_BLOCK_PICTURE
					// The unencoded format is that of the FLAC picture block. The fields are stored in big endian order as in FLAC, picture data is stored according to the relevant standard.
					// http://flac.sourceforge.net/format.html#metadata_block_picture
					$flac = new getid3_flac($this->getid3);
					$flac->setStringMode(base64_decode($ThisFileInfo_ogg_comments_raw[$i]['value']));
					$flac->parsePICTURE();
					$info['ogg']['comments']['picture'][] = $flac->getid3->info['flac']['PICTURE'][0];
					unset($flac);

				} elseif ($ThisFileInfo_ogg_comments_raw[$i]['key'] == 'COVERART') {

					$data = base64_decode($ThisFileInfo_ogg_comments_raw[$i]['value']);
					$this->notice('Found deprecated COVERART tag, it should be replaced in honor of METADATA_BLOCK_PICTURE structure');
					/** @todo use 'coverartmime' where available */
					$imageinfo = getid3_lib::GetDataImageSize($data);
					if ($imageinfo === false || !isset($imageinfo['mime'])) {
						$this->warning('COVERART vorbiscomment tag contains invalid image');
						continue;
					}

					$ogg = new self($this->getid3);
					$ogg->setStringMode($data);
					$info['ogg']['comments']['picture'][] = array(
						'image_mime'   => $imageinfo['mime'],
						'datalength'   => strlen($data),
						'picturetype'  => 'cover art',
						'image_height' => $imageinfo['height'],
						'image_width'  => $imageinfo['width'],
						'data'         => $ogg->saveAttachment('coverart', 0, strlen($data), $imageinfo['mime']),
					);
					unset($ogg);

				} else {

					$info['ogg']['comments'][strtolower($ThisFileInfo_ogg_comments_raw[$i]['key'])][] = $ThisFileInfo_ogg_comments_raw[$i]['value'];

				}

			} else {

				$this->warning('[known problem with CDex >= v1.40, < v1.50b7] Invalid Ogg comment name/value pair ['.$i.']: '.$commentstring);

			}
			unset($ThisFileInfo_ogg_comments_raw[$i]);
		}
		unset($ThisFileInfo_ogg_comments_raw);

		// Replay Gain Adjustment
		// http://privatewww.essex.ac.uk/~djmrob/replaygain/
		if (isset($info['ogg']['comments']) && is_array($info['ogg']['comments'])) {
			foreach ($info['ogg']['comments'] as $index => $commentvalue) {
				switch ($index) {
					case 'rg_audiophile':
					case 'replaygain_album_gain':
						$info['replay_gain']['album']['adjustment'] = (double) $commentvalue[0];
						unset($info['ogg']['comments'][$index]);
						break;

					case 'rg_radio':
					case 'replaygain_track_gain':
						$info['replay_gain']['track']['adjustment'] = (double) $commentvalue[0];
						unset($info['ogg']['comments'][$index]);
						break;

					case 'replaygain_album_peak':
						$info['replay_gain']['album']['peak'] = (double) $commentvalue[0];
						unset($info['ogg']['comments'][$index]);
						break;

					case 'rg_peak':
					case 'replaygain_track_peak':
						$info['replay_gain']['track']['peak'] = (double) $commentvalue[0];
						unset($info['ogg']['comments'][$index]);
						break;

					case 'replaygain_reference_loudness':
						$info['replay_gain']['reference_volume'] = (double) $commentvalue[0];
						unset($info['ogg']['comments'][$index]);
						break;

					default:
						// do nothing
						break;
				}
			}
		}

		$this->fseek($OriginalOffset);

		return true;
	}

	/**
	 * @param int $mode
	 *
	 * @return string|null
	 */
	public static function SpeexBandModeLookup($mode) {
		static $SpeexBandModeLookup = array();
		if (empty($SpeexBandModeLookup)) {
			$SpeexBandModeLookup[0] = 'narrow';
			$SpeexBandModeLookup[1] = 'wide';
			$SpeexBandModeLookup[2] = 'ultra-wide';
		}
		return (isset($SpeexBandModeLookup[$mode]) ? $SpeexBandModeLookup[$mode] : null);
	}

	/**
	 * @param array $OggInfoArray
	 * @param int   $SegmentNumber
	 *
	 * @return int
	 */
	public static function OggPageSegmentLength($OggInfoArray, $SegmentNumber=1) {
		$segmentlength = 0;
		for ($i = 0; $i < $SegmentNumber; $i++) {
			$segmentlength = 0;
			foreach ($OggInfoArray['segment_table'] as $key => $value) {
				$segmentlength += $value;
				if ($value < 255) {
					break;
				}
			}
		}
		return $segmentlength;
	}

	/**
	 * @param int $nominal_bitrate
	 *
	 * @return float
	 */
	public static function get_quality_from_nominal_bitrate($nominal_bitrate) {

		// decrease precision
		$nominal_bitrate = $nominal_bitrate / 1000;

		if ($nominal_bitrate < 128) {
			// q-1 to q4
			$qval = ($nominal_bitrate - 64) / 16;
		} elseif ($nominal_bitrate < 256) {
			// q4 to q8
			$qval = $nominal_bitrate / 32;
		} elseif ($nominal_bitrate < 320) {
			// q8 to q9
			$qval = ($nominal_bitrate + 256) / 64;
		} else {
			// q9 to q10
			$qval = ($nominal_bitrate + 1300) / 180;
		}
		//return $qval; // 5.031324
		//return intval($qval); // 5
		return round($qval, 1); // 5 or 4.9
	}

	/**
	 * @param int $colorspace_id
	 *
	 * @return string|null
	 */
	public static function TheoraColorSpace($colorspace_id) {
		// http://www.theora.org/doc/Theora.pdf (table 6.3)
		static $TheoraColorSpaceLookup = array();
		if (empty($TheoraColorSpaceLookup)) {
			$TheoraColorSpaceLookup[0] = 'Undefined';
			$TheoraColorSpaceLookup[1] = 'Rec. 470M';
			$TheoraColorSpaceLookup[2] = 'Rec. 470BG';
			$TheoraColorSpaceLookup[3] = 'Reserved';
		}
		return (isset($TheoraColorSpaceLookup[$colorspace_id]) ? $TheoraColorSpaceLookup[$colorspace_id] : null);
	}

	/**
	 * @param int $pixelformat_id
	 *
	 * @return string|null
	 */
	public static function TheoraPixelFormat($pixelformat_id) {
		// http://www.theora.org/doc/Theora.pdf (table 6.4)
		static $TheoraPixelFormatLookup = array();
		if (empty($TheoraPixelFormatLookup)) {
			$TheoraPixelFormatLookup[0] = '4:2:0';
			$TheoraPixelFormatLookup[1] = 'Reserved';
			$TheoraPixelFormatLookup[2] = '4:2:2';
			$TheoraPixelFormatLookup[3] = '4:4:4';
		}
		return (isset($TheoraPixelFormatLookup[$pixelformat_id]) ? $TheoraPixelFormatLookup[$pixelformat_id] : null);
	}

}


<?php

/////////////////////////////////////////////////////////////////
/// getID3() by James Heinrich <info@getid3.org>               //
//  available at https://github.com/JamesHeinrich/getID3       //
//            or https://www.getid3.org                        //
//            or http://getid3.sourceforge.net                 //
//  see readme.txt for more details                            //
/////////////////////////////////////////////////////////////////
//                                                             //
// module.tag.apetag.php                                       //
// module for analyzing APE tags                               //
// dependencies: NONE                                          //
//                                                            ///
/////////////////////////////////////////////////////////////////

if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers
	exit;
}

class getid3_apetag extends getid3_handler
{
	/**
	 * true: return full data for all attachments;
	 * false: return no data for all attachments;
	 * integer: return data for attachments <= than this;
	 * string: save as file to this directory.
	 *
	 * @var int|bool|string
	 */
	public $inline_attachments = true;

	public $overrideendoffset  = 0;

	/**
	 * @return bool
	 */
	public function Analyze() {
		$info = &$this->getid3->info;

		if (!getid3_lib::intValueSupported($info['filesize'])) {
			$this->warning('Unable to check for APEtags because file is larger than '.round(PHP_INT_MAX / 1073741824).'GB');
			return false;
		}

		$id3v1tagsize     = 128;
		$apetagheadersize = 32;
		$lyrics3tagsize   = 10;

		if ($this->overrideendoffset == 0) {

			$this->fseek(0 - $id3v1tagsize - $apetagheadersize - $lyrics3tagsize, SEEK_END);
			$APEfooterID3v1 = $this->fread($id3v1tagsize + $apetagheadersize + $lyrics3tagsize);

			//if (preg_match('/APETAGEX.{24}TAG.{125}$/i', $APEfooterID3v1)) {
			if (substr($APEfooterID3v1, strlen($APEfooterID3v1) - $id3v1tagsize - $apetagheadersize, 8) == 'APETAGEX') {

				// APE tag found before ID3v1
				$info['ape']['tag_offset_end'] = $info['filesize'] - $id3v1tagsize;

			//} elseif (preg_match('/APETAGEX.{24}$/i', $APEfooterID3v1)) {
			} elseif (substr($APEfooterID3v1, strlen($APEfooterID3v1) - $apetagheadersize, 8) == 'APETAGEX') {

				// APE tag found, no ID3v1
				$info['ape']['tag_offset_end'] = $info['filesize'];

			}

		} else {

			$this->fseek($this->overrideendoffset - $apetagheadersize);
			if ($this->fread(8) == 'APETAGEX') {
				$info['ape']['tag_offset_end'] = $this->overrideendoffset;
			}

		}
		if (!isset($info['ape']['tag_offset_end'])) {

			// APE tag not found
			unset($info['ape']);
			return false;

		}

		// shortcut
		$thisfile_ape = &$info['ape'];

		$this->fseek($thisfile_ape['tag_offset_end'] - $apetagheadersize);
		$APEfooterData = $this->fread(32);
		if (!($thisfile_ape['footer'] = $this->parseAPEheaderFooter($APEfooterData))) {
			$this->error('Error parsing APE footer at offset '.$thisfile_ape['tag_offset_end']);
			return false;
		}

		if (isset($thisfile_ape['footer']['flags']['header']) && $thisfile_ape['footer']['flags']['header']) {
			$this->fseek($thisfile_ape['tag_offset_end'] - $thisfile_ape['footer']['raw']['tagsize'] - $apetagheadersize);
			$thisfile_ape['tag_offset_start'] = $this->ftell();
			$APEtagData = $this->fread($thisfile_ape['footer']['raw']['tagsize'] + $apetagheadersize);
		} else {
			$thisfile_ape['tag_offset_start'] = $thisfile_ape['tag_offset_end'] - $thisfile_ape['footer']['raw']['tagsize'];
			$this->fseek($thisfile_ape['tag_offset_start']);
			$APEtagData = $this->fread($thisfile_ape['footer']['raw']['tagsize']);
		}
		$info['avdataend'] = $thisfile_ape['tag_offset_start'];

		if (isset($info['id3v1']['tag_offset_start']) && ($info['id3v1']['tag_offset_start'] < $thisfile_ape['tag_offset_end'])) {
			$this->warning('ID3v1 tag information ignored since it appears to be a false synch in APEtag data');
			unset($info['id3v1']);
			foreach ($info['warning'] as $key => $value) {
				if ($value == 'Some ID3v1 fields do not use NULL characters for padding') {
					unset($info['warning'][$key]);
					sort($info['warning']);
					break;
				}
			}
		}

		$offset = 0;
		if (isset($thisfile_ape['footer']['flags']['header']) && $thisfile_ape['footer']['flags']['header']) {
			if ($thisfile_ape['header'] = $this->parseAPEheaderFooter(substr($APEtagData, 0, $apetagheadersize))) {
				$offset += $apetagheadersize;
			} else {
				$this->error('Error parsing APE header at offset '.$thisfile_ape['tag_offset_start']);
				return false;
			}
		}

		// shortcut
		$info['replay_gain'] = array();
		$thisfile_replaygain = &$info['replay_gain'];

		for ($i = 0; $i < $thisfile_ape['footer']['raw']['tag_items']; $i++) {
			$value_size = getid3_lib::LittleEndian2Int(substr($APEtagData, $offset, 4));
			$offset += 4;
			$item_flags = getid3_lib::LittleEndian2Int(substr($APEtagData, $offset, 4));
			$offset += 4;
			if (strstr(substr($APEtagData, $offset), "\x00") === false) {
				$this->error('Cannot find null-byte (0x00) separator between ItemKey #'.$i.' and value. ItemKey starts '.$offset.' bytes into the APE tag, at file offset '.($thisfile_ape['tag_offset_start'] + $offset));
				return false;
			}
			$ItemKeyLength = strpos($APEtagData, "\x00", $offset) - $offset;
			$item_key      = strtolower(substr($APEtagData, $offset, $ItemKeyLength));

			// shortcut
			$thisfile_ape['items'][$item_key] = array();
			$thisfile_ape_items_current = &$thisfile_ape['items'][$item_key];

			$thisfile_ape_items_current['offset'] = $thisfile_ape['tag_offset_start'] + $offset;

			$offset += ($ItemKeyLength + 1); // skip 0x00 terminator
			$thisfile_ape_items_current['data'] = substr($APEtagData, $offset, $value_size);
			$offset += $value_size;

			$thisfile_ape_items_current['flags'] = $this->parseAPEtagFlags($item_flags);
			switch ($thisfile_ape_items_current['flags']['item_contents_raw']) {
				case 0: // UTF-8
				case 2: // Locator (URL, filename, etc), UTF-8 encoded
					$thisfile_ape_items_current['data'] = explode("\x00", $thisfile_ape_items_current['data']);
					break;

				case 1:  // binary data
				default:
					break;
			}

			switch (strtolower($item_key)) {
				// http://wiki.hydrogenaud.io/index.php?title=ReplayGain#MP3Gain
				case 'replaygain_track_gain':
					if (preg_match('#^([\\-\\+][0-9\\.,]{8})( dB)?$#', $thisfile_ape_items_current['data'][0], $matches)) {
						$thisfile_replaygain['track']['adjustment'] = (float) str_replace(',', '.', $matches[1]); // float casting will see "0,95" as zero!
						$thisfile_replaygain['track']['originator'] = 'unspecified';
					} else {
						$this->warning('MP3gainTrackGain value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');
					}
					break;

				case 'replaygain_track_peak':
					if (preg_match('#^([0-9\\.,]{8})$#', $thisfile_ape_items_current['data'][0], $matches)) {
						$thisfile_replaygain['track']['peak']       = (float) str_replace(',', '.', $matches[1]); // float casting will see "0,95" as zero!
						$thisfile_replaygain['track']['originator'] = 'unspecified';
						if ($thisfile_replaygain['track']['peak'] <= 0) {
							$this->warning('ReplayGain Track peak from APEtag appears invalid: '.$thisfile_replaygain['track']['peak'].' (original value = "'.$thisfile_ape_items_current['data'][0].'")');
						}
					} else {
						$this->warning('MP3gainTrackPeak value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');
					}
					break;

				case 'replaygain_album_gain':
					if (preg_match('#^([\\-\\+][0-9\\.,]{8})( dB)?$#', $thisfile_ape_items_current['data'][0], $matches)) {
						$thisfile_replaygain['album']['adjustment'] = (float) str_replace(',', '.', $matches[1]); // float casting will see "0,95" as zero!
						$thisfile_replaygain['album']['originator'] = 'unspecified';
					} else {
						$this->warning('MP3gainAlbumGain value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');
					}
					break;

				case 'replaygain_album_peak':
					if (preg_match('#^([0-9\\.,]{8})$#', $thisfile_ape_items_current['data'][0], $matches)) {
						$thisfile_replaygain['album']['peak']       = (float) str_replace(',', '.', $matches[1]); // float casting will see "0,95" as zero!
						$thisfile_replaygain['album']['originator'] = 'unspecified';
						if ($thisfile_replaygain['album']['peak'] <= 0) {
							$this->warning('ReplayGain Album peak from APEtag appears invalid: '.$thisfile_replaygain['album']['peak'].' (original value = "'.$thisfile_ape_items_current['data'][0].'")');
						}
					} else {
						$this->warning('MP3gainAlbumPeak value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');
					}
					break;

				case 'mp3gain_undo':
					if (preg_match('#^[\\-\\+][0-9]{3},[\\-\\+][0-9]{3},[NW]$#', $thisfile_ape_items_current['data'][0])) {
						list($mp3gain_undo_left, $mp3gain_undo_right, $mp3gain_undo_wrap) = explode(',', $thisfile_ape_items_current['data'][0]);
						$thisfile_replaygain['mp3gain']['undo_left']  = intval($mp3gain_undo_left);
						$thisfile_replaygain['mp3gain']['undo_right'] = intval($mp3gain_undo_right);
						$thisfile_replaygain['mp3gain']['undo_wrap']  = (($mp3gain_undo_wrap == 'Y') ? true : false);
					} else {
						$this->warning('MP3gainUndo value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');
					}
					break;

				case 'mp3gain_minmax':
					if (preg_match('#^[0-9]{3},[0-9]{3}$#', $thisfile_ape_items_current['data'][0])) {
						list($mp3gain_globalgain_min, $mp3gain_globalgain_max) = explode(',', $thisfile_ape_items_current['data'][0]);
						$thisfile_replaygain['mp3gain']['globalgain_track_min'] = intval($mp3gain_globalgain_min);
						$thisfile_replaygain['mp3gain']['globalgain_track_max'] = intval($mp3gain_globalgain_max);
					} else {
						$this->warning('MP3gainMinMax value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');
					}
					break;

				case 'mp3gain_album_minmax':
					if (preg_match('#^[0-9]{3},[0-9]{3}$#', $thisfile_ape_items_current['data'][0])) {
						list($mp3gain_globalgain_album_min, $mp3gain_globalgain_album_max) = explode(',', $thisfile_ape_items_current['data'][0]);
						$thisfile_replaygain['mp3gain']['globalgain_album_min'] = intval($mp3gain_globalgain_album_min);
						$thisfile_replaygain['mp3gain']['globalgain_album_max'] = intval($mp3gain_globalgain_album_max);
					} else {
						$this->warning('MP3gainAlbumMinMax value in APEtag appears invalid: "'.$thisfile_ape_items_current['data'][0].'"');
					}
					break;

				case 'tracknumber':
					if (is_array($thisfile_ape_items_current['data'])) {
						foreach ($thisfile_ape_items_current['data'] as $comment) {
							$thisfile_ape['comments']['track_number'][] = $comment;
						}
					}
					break;

				case 'cover art (artist)':
				case 'cover art (back)':
				case 'cover art (band logo)':
				case 'cover art (band)':
				case 'cover art (colored fish)':
				case 'cover art (composer)':
				case 'cover art (conductor)':
				case 'cover art (front)':
				case 'cover art (icon)':
				case 'cover art (illustration)':
				case 'cover art (lead)':
				case 'cover art (leaflet)':
				case 'cover art (lyricist)':
				case 'cover art (media)':
				case 'cover art (movie scene)':
				case 'cover art (other icon)':
				case 'cover art (other)':
				case 'cover art (performance)':
				case 'cover art (publisher logo)':
				case 'cover art (recording)':
				case 'cover art (studio)':
					// list of possible cover arts from http://taglib-sharp.sourcearchive.com/documentation/2.0.3.0-2/Ape_2Tag_8cs-source.html
					if (is_array($thisfile_ape_items_current['data'])) {
						$this->warning('APEtag "'.$item_key.'" should be flagged as Binary data, but was incorrectly flagged as UTF-8');
						$thisfile_ape_items_current['data'] = implode("\x00", $thisfile_ape_items_current['data']);
					}
					list($thisfile_ape_items_current['filename'], $thisfile_ape_items_current['data']) = explode("\x00", $thisfile_ape_items_current['data'], 2);
					$thisfile_ape_items_current['data_offset'] = $thisfile_ape_items_current['offset'] + strlen($thisfile_ape_items_current['filename']."\x00");
					$thisfile_ape_items_current['data_length'] = strlen($thisfile_ape_items_current['data']);

					do {
						$thisfile_ape_items_current['image_mime'] = '';
						$imageinfo = array();
						$imagechunkcheck = getid3_lib::GetDataImageSize($thisfile_ape_items_current['data'], $imageinfo);
						if (($imagechunkcheck === false) || !isset($imagechunkcheck[2])) {
							$this->warning('APEtag "'.$item_key.'" contains invalid image data');
							break;
						}
						$thisfile_ape_items_current['image_mime'] = image_type_to_mime_type($imagechunkcheck[2]);

						if ($this->inline_attachments === false) {
							// skip entirely
							unset($thisfile_ape_items_current['data']);
							break;
						}
						if ($this->inline_attachments === true) {
							// great
						} elseif (is_int($this->inline_attachments)) {
							if ($this->inline_attachments < $thisfile_ape_items_current['data_length']) {
								// too big, skip
								$this->warning('attachment at '.$thisfile_ape_items_current['offset'].' is too large to process inline ('.number_format($thisfile_ape_items_current['data_length']).' bytes)');
								unset($thisfile_ape_items_current['data']);
								break;
							}
						} elseif (is_string($this->inline_attachments)) {
							$this->inline_attachments = rtrim(str_replace(array('/', '\\'), DIRECTORY_SEPARATOR, $this->inline_attachments), DIRECTORY_SEPARATOR);
							if (!is_dir($this->inline_attachments) || !getID3::is_writable($this->inline_attachments)) {
								// cannot write, skip
								$this->warning('attachment at '.$thisfile_ape_items_current['offset'].' cannot be saved to "'.$this->inline_attachments.'" (not writable)');
								unset($thisfile_ape_items_current['data']);
								break;
							}
						}
						// if we get this far, must be OK
						if (is_string($this->inline_attachments)) {
							$destination_filename = $this->inline_attachments.DIRECTORY_SEPARATOR.md5($info['filenamepath']).'_'.$thisfile_ape_items_current['data_offset'];
							if (!file_exists($destination_filename) || getID3::is_writable($destination_filename)) {
								file_put_contents($destination_filename, $thisfile_ape_items_current['data']);
							} else {
								$this->warning('attachment at '.$thisfile_ape_items_current['offset'].' cannot be saved to "'.$destination_filename.'" (not writable)');
							}
							$thisfile_ape_items_current['data_filename'] = $destination_filename;
							unset($thisfile_ape_items_current['data']);
						} else {
							if (!isset($info['ape']['comments']['picture'])) {
								$info['ape']['comments']['picture'] = array();
							}
							$comments_picture_data = array();
							foreach (array('data', 'image_mime', 'image_width', 'image_height', 'imagetype', 'picturetype', 'description', 'datalength') as $picture_key) {
								if (isset($thisfile_ape_items_current[$picture_key])) {
									$comments_picture_data[$picture_key] = $thisfile_ape_items_current[$picture_key];
								}
							}
							$info['ape']['comments']['picture'][] = $comments_picture_data;
							unset($comments_picture_data);
						}
					} while (false);
					break;

				default:
					if (is_array($thisfile_ape_items_current['data'])) {
						foreach ($thisfile_ape_items_current['data'] as $comment) {
							$thisfile_ape['comments'][strtolower($item_key)][] = $comment;
						}
					}
					break;
			}

		}
		if (empty($thisfile_replaygain)) {
			unset($info['replay_gain']);
		}
		return true;
	}

	/**
	 * @param string $APEheaderFooterData
	 *
	 * @return array|false
	 */
	public function parseAPEheaderFooter($APEheaderFooterData) {
		// http://www.uni-jena.de/~pfk/mpp/sv8/apeheader.html

		// shortcut
		$headerfooterinfo['raw'] = array();
		$headerfooterinfo_raw = &$headerfooterinfo['raw'];

		$headerfooterinfo_raw['footer_tag']   =                  substr($APEheaderFooterData,  0, 8);
		if ($headerfooterinfo_raw['footer_tag'] != 'APETAGEX') {
			return false;
		}
		$headerfooterinfo_raw['version']      = getid3_lib::LittleEndian2Int(substr($APEheaderFooterData,  8, 4));
		$headerfooterinfo_raw['tagsize']      = getid3_lib::LittleEndian2Int(substr($APEheaderFooterData, 12, 4));
		$headerfooterinfo_raw['tag_items']    = getid3_lib::LittleEndian2Int(substr($APEheaderFooterData, 16, 4));
		$headerfooterinfo_raw['global_flags'] = getid3_lib::LittleEndian2Int(substr($APEheaderFooterData, 20, 4));
		$headerfooterinfo_raw['reserved']     =                              substr($APEheaderFooterData, 24, 8);

		$headerfooterinfo['tag_version']         = $headerfooterinfo_raw['version'] / 1000;
		if ($headerfooterinfo['tag_version'] >= 2) {
			$headerfooterinfo['flags'] = $this->parseAPEtagFlags($headerfooterinfo_raw['global_flags']);
		}
		return $headerfooterinfo;
	}

	/**
	 * @param int $rawflagint
	 *
	 * @return array
	 */
	public function parseAPEtagFlags($rawflagint) {
		// "Note: APE Tags 1.0 do not use any of the APE Tag flags.
		// All are set to zero on creation and ignored on reading."
		// http://wiki.hydrogenaud.io/index.php?title=Ape_Tags_Flags
		$flags['header']            = (bool) ($rawflagint & 0x80000000);
		$flags['footer']            = (bool) ($rawflagint & 0x40000000);
		$flags['this_is_header']    = (bool) ($rawflagint & 0x20000000);
		$flags['item_contents_raw'] =        ($rawflagint & 0x00000006) >> 1;
		$flags['read_only']         = (bool) ($rawflagint & 0x00000001);

		$flags['item_contents']     = $this->APEcontentTypeFlagLookup($flags['item_contents_raw']);

		return $flags;
	}

	/**
	 * @param int $contenttypeid
	 *
	 * @return string
	 */
	public function APEcontentTypeFlagLookup($contenttypeid) {
		static $APEcontentTypeFlagLookup = array(
			0 => 'utf-8',
			1 => 'binary',
			2 => 'external',
			3 => 'reserved'
		);
		return (isset($APEcontentTypeFlagLookup[$contenttypeid]) ? $APEcontentTypeFlagLookup[$contenttypeid] : 'invalid');
	}

	/**
	 * @param string $itemkey
	 *
	 * @return bool
	 */
	public function APEtagItemIsUTF8Lookup($itemkey) {
		static $APEtagItemIsUTF8Lookup = array(
			'title',
			'subtitle',
			'artist',
			'album',
			'debut album',
			'publisher',
			'conductor',
			'track',
			'composer',
			'comment',
			'copyright',
			'publicationright',
			'file',
			'year',
			'record date',
			'record location',
			'genre',
			'media',
			'related',
			'isrc',
			'abstract',
			'language',
			'bibliography'
		);
		return in_array(strtolower($itemkey), $APEtagItemIsUTF8Lookup);
	}

}


<?php

/////////////////////////////////////////////////////////////////
/// getID3() by James Heinrich <info@getid3.org>               //
//  available at https://github.com/JamesHeinrich/getID3       //
//            or https://www.getid3.org                        //
//            or http://getid3.sourceforge.net                 //
//  see readme.txt for more details                            //
/////////////////////////////////////////////////////////////////
//                                                             //
// module.tag.id3v1.php                                        //
// module for analyzing ID3v1 tags                             //
// dependencies: NONE                                          //
//                                                            ///
/////////////////////////////////////////////////////////////////

if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers
	exit;
}

class getid3_id3v1 extends getid3_handler
{
	/**
	 * @return bool
	 */
	public function Analyze() {
		$info = &$this->getid3->info;

		if (!getid3_lib::intValueSupported($info['filesize'])) {
			$this->warning('Unable to check for ID3v1 because file is larger than '.round(PHP_INT_MAX / 1073741824).'GB');
			return false;
		}

		$this->fseek(-256, SEEK_END);
		$preid3v1 = $this->fread(128);
		$id3v1tag = $this->fread(128);

		if (substr($id3v1tag, 0, 3) == 'TAG') {

			$info['avdataend'] = $info['filesize'] - 128;

			$ParsedID3v1['title']   = $this->cutfield(substr($id3v1tag,   3, 30));
			$ParsedID3v1['artist']  = $this->cutfield(substr($id3v1tag,  33, 30));
			$ParsedID3v1['album']   = $this->cutfield(substr($id3v1tag,  63, 30));
			$ParsedID3v1['year']    = $this->cutfield(substr($id3v1tag,  93,  4));
			$ParsedID3v1['comment'] =                 substr($id3v1tag,  97, 30);  // can't remove nulls yet, track detection depends on them
			$ParsedID3v1['genreid'] =             ord(substr($id3v1tag, 127,  1));

			// If second-last byte of comment field is null and last byte of comment field is non-null
			// then this is ID3v1.1 and the comment field is 28 bytes long and the 30th byte is the track number
			if (($id3v1tag[125] === "\x00") && ($id3v1tag[126] !== "\x00")) {
				$ParsedID3v1['track_number'] = ord(substr($ParsedID3v1['comment'], 29,  1));
				$ParsedID3v1['comment']      =     substr($ParsedID3v1['comment'],  0, 28);
			}
			$ParsedID3v1['comment'] = $this->cutfield($ParsedID3v1['comment']);

			$ParsedID3v1['genre'] = $this->LookupGenreName($ParsedID3v1['genreid']);
			if (!empty($ParsedID3v1['genre'])) {
				unset($ParsedID3v1['genreid']);
			}
			if (isset($ParsedID3v1['genre']) && (empty($ParsedID3v1['genre']) || ($ParsedID3v1['genre'] == 'Unknown'))) {
				unset($ParsedID3v1['genre']);
			}

			foreach ($ParsedID3v1 as $key => $value) {
				$ParsedID3v1['comments'][$key][0] = $value;
			}
			$ID3v1encoding = $this->getid3->encoding_id3v1;
			if ($this->getid3->encoding_id3v1_autodetect) {
				// ID3v1 encoding detection hack START
				// ID3v1 is defined as always using ISO-8859-1 encoding, but it is not uncommon to find files tagged with ID3v1 using Windows-1251 or other character sets
				// Since ID3v1 has no concept of character sets there is no certain way to know we have the correct non-ISO-8859-1 character set, but we can guess
				foreach ($ParsedID3v1['comments'] as $tag_key => $valuearray) {
					foreach ($valuearray as $key => $value) {
						if (preg_match('#^[\\x00-\\x40\\x80-\\xFF]+$#', $value) && !ctype_digit((string) $value)) { // check for strings with only characters above chr(128) and punctuation/numbers, but not just numeric strings (e.g. track numbers or years)
							foreach (array('Windows-1251', 'KOI8-R') as $id3v1_bad_encoding) {
								if (function_exists('mb_convert_encoding') && @mb_convert_encoding($value, $id3v1_bad_encoding, $id3v1_bad_encoding) === $value) {
									$ID3v1encoding = $id3v1_bad_encoding;
									$this->warning('ID3v1 detected as '.$id3v1_bad_encoding.' text encoding in '.$tag_key);
									break 3;
								} elseif (function_exists('iconv') && @iconv($id3v1_bad_encoding, $id3v1_bad_encoding, $value) === $value) {
									$ID3v1encoding = $id3v1_bad_encoding;
									$this->warning('ID3v1 detected as '.$id3v1_bad_encoding.' text encoding in '.$tag_key);
									break 3;
								}
							}
						}
					}
				}
				// ID3v1 encoding detection hack END
			}

			// ID3v1 data is supposed to be padded with NULL characters, but some taggers pad with spaces
			$GoodFormatID3v1tag = $this->GenerateID3v1Tag(
											$ParsedID3v1['title'],
											$ParsedID3v1['artist'],
											$ParsedID3v1['album'],
											$ParsedID3v1['year'],
											(isset($ParsedID3v1['genre']) ? $this->LookupGenreID($ParsedID3v1['genre']) : false),
											$ParsedID3v1['comment'],
											(!empty($ParsedID3v1['track_number']) ? $ParsedID3v1['track_number'] : ''));
			$ParsedID3v1['padding_valid'] = true;
			if ($id3v1tag !== $GoodFormatID3v1tag) {
				$ParsedID3v1['padding_valid'] = false;
				$this->warning('Some ID3v1 fields do not use NULL characters for padding');
			}

			$ParsedID3v1['tag_offset_end']   = $info['filesize'];
			$ParsedID3v1['tag_offset_start'] = $ParsedID3v1['tag_offset_end'] - 128;

			$info['id3v1'] = $ParsedID3v1;
			$info['id3v1']['encoding'] = $ID3v1encoding;
		}

		if (substr($preid3v1, 0, 3) == 'TAG') {
			// The way iTunes handles tags is, well, brain-damaged.
			// It completely ignores v1 if ID3v2 is present.
			// This goes as far as adding a new v1 tag *even if there already is one*

			// A suspected double-ID3v1 tag has been detected, but it could be that
			// the "TAG" identifier is a legitimate part of an APE or Lyrics3 tag
			if (substr($preid3v1, 96, 8) == 'APETAGEX') {
				// an APE tag footer was found before the last ID3v1, assume false "TAG" synch
			} elseif (substr($preid3v1, 119, 6) == 'LYRICS') {
				// a Lyrics3 tag footer was found before the last ID3v1, assume false "TAG" synch
			} else {
				// APE and Lyrics3 footers not found - assume double ID3v1
				$this->warning('Duplicate ID3v1 tag detected - this has been known to happen with iTunes');
				$info['avdataend'] -= 128;
			}
		}

		return true;
	}

	/**
	 * @param string $str
	 *
	 * @return string
	 */
	public static function cutfield($str) {
		return trim(substr($str, 0, strcspn($str, "\x00")));
	}

	/**
	 * @param bool $allowSCMPXextended
	 *
	 * @return string[]
	 */
	public static function ArrayOfGenres($allowSCMPXextended=false) {
		static $GenreLookup = array(
			0    => 'Blues',
			1    => 'Classic Rock',
			2    => 'Country',
			3    => 'Dance',
			4    => 'Disco',
			5    => 'Funk',
			6    => 'Grunge',
			7    => 'Hip-Hop',
			8    => 'Jazz',
			9    => 'Metal',
			10   => 'New Age',
			11   => 'Oldies',
			12   => 'Other',
			13   => 'Pop',
			14   => 'R&B',
			15   => 'Rap',
			16   => 'Reggae',
			17   => 'Rock',
			18   => 'Techno',
			19   => 'Industrial',
			20   => 'Alternative',
			21   => 'Ska',
			22   => 'Death Metal',
			23   => 'Pranks',
			24   => 'Soundtrack',
			25   => 'Euro-Techno',
			26   => 'Ambient',
			27   => 'Trip-Hop',
			28   => 'Vocal',
			29   => 'Jazz+Funk',
			30   => 'Fusion',
			31   => 'Trance',
			32   => 'Classical',
			33   => 'Instrumental',
			34   => 'Acid',
			35   => 'House',
			36   => 'Game',
			37   => 'Sound Clip',
			38   => 'Gospel',
			39   => 'Noise',
			40   => 'Alt. Rock',
			41   => 'Bass',
			42   => 'Soul',
			43   => 'Punk',
			44   => 'Space',
			45   => 'Meditative',
			46   => 'Instrumental Pop',
			47   => 'Instrumental Rock',
			48   => 'Ethnic',
			49   => 'Gothic',
			50   => 'Darkwave',
			51   => 'Techno-Industrial',
			52   => 'Electronic',
			53   => 'Pop-Folk',
			54   => 'Eurodance',
			55   => 'Dream',
			56   => 'Southern Rock',
			57   => 'Comedy',
			58   => 'Cult',
			59   => 'Gangsta Rap',
			60   => 'Top 40',
			61   => 'Christian Rap',
			62   => 'Pop/Funk',
			63   => 'Jungle',
			64   => 'Native American',
			65   => 'Cabaret',
			66   => 'New Wave',
			67   => 'Psychedelic',
			68   => 'Rave',
			69   => 'Showtunes',
			70   => 'Trailer',
			71   => 'Lo-Fi',
			72   => 'Tribal',
			73   => 'Acid Punk',
			74   => 'Acid Jazz',
			75   => 'Polka',
			76   => 'Retro',
			77   => 'Musical',
			78   => 'Rock & Roll',
			79   => 'Hard Rock',
			80   => 'Folk',
			81   => 'Folk/Rock',
			82   => 'National Folk',
			83   => 'Swing',
			84   => 'Fast-Fusion',
			85   => 'Bebob',
			86   => 'Latin',
			87   => 'Revival',
			88   => 'Celtic',
			89   => 'Bluegrass',
			90   => 'Avantgarde',
			91   => 'Gothic Rock',
			92   => 'Progressive Rock',
			93   => 'Psychedelic Rock',
			94   => 'Symphonic Rock',
			95   => 'Slow Rock',
			96   => 'Big Band',
			97   => 'Chorus',
			98   => 'Easy Listening',
			99   => 'Acoustic',
			100  => 'Humour',
			101  => 'Speech',
			102  => 'Chanson',
			103  => 'Opera',
			104  => 'Chamber Music',
			105  => 'Sonata',
			106  => 'Symphony',
			107  => 'Booty Bass',
			108  => 'Primus',
			109  => 'Porn Groove',
			110  => 'Satire',
			111  => 'Slow Jam',
			112  => 'Club',
			113  => 'Tango',
			114  => 'Samba',
			115  => 'Folklore',
			116  => 'Ballad',
			117  => 'Power Ballad',
			118  => 'Rhythmic Soul',
			119  => 'Freestyle',
			120  => 'Duet',
			121  => 'Punk Rock',
			122  => 'Drum Solo',
			123  => 'A Cappella',
			124  => 'Euro-House',
			125  => 'Dance Hall',
			126  => 'Goa',
			127  => 'Drum & Bass',
			128  => 'Club-House',
			129  => 'Hardcore',
			130  => 'Terror',
			131  => 'Indie',
			132  => 'BritPop',
			133  => 'Negerpunk',
			134  => 'Polsk Punk',
			135  => 'Beat',
			136  => 'Christian Gangsta Rap',
			137  => 'Heavy Metal',
			138  => 'Black Metal',
			139  => 'Crossover',
			140  => 'Contemporary Christian',
			141  => 'Christian Rock',
			142  => 'Merengue',
			143  => 'Salsa',
			144  => 'Thrash Metal',
			145  => 'Anime',
			146  => 'JPop',
			147  => 'Synthpop',

			255  => 'Unknown',

			'CR' => 'Cover',
			'RX' => 'Remix'
		);

		static $GenreLookupSCMPX = array();
		if ($allowSCMPXextended && empty($GenreLookupSCMPX)) {
			$GenreLookupSCMPX = $GenreLookup;
			// http://www.geocities.co.jp/SiliconValley-Oakland/3664/alittle.html#GenreExtended
			// Extended ID3v1 genres invented by SCMPX
			// Note that 255 "Japanese Anime" conflicts with standard "Unknown"
			$GenreLookupSCMPX[240] = 'Sacred';
			$GenreLookupSCMPX[241] = 'Northern Europe';
			$GenreLookupSCMPX[242] = 'Irish & Scottish';
			$GenreLookupSCMPX[243] = 'Scotland';
			$GenreLookupSCMPX[244] = 'Ethnic Europe';
			$GenreLookupSCMPX[245] = 'Enka';
			$GenreLookupSCMPX[246] = 'Children\'s Song';
			$GenreLookupSCMPX[247] = 'Japanese Sky';
			$GenreLookupSCMPX[248] = 'Japanese Heavy Rock';
			$GenreLookupSCMPX[249] = 'Japanese Doom Rock';
			$GenreLookupSCMPX[250] = 'Japanese J-POP';
			$GenreLookupSCMPX[251] = 'Japanese Seiyu';
			$GenreLookupSCMPX[252] = 'Japanese Ambient Techno';
			$GenreLookupSCMPX[253] = 'Japanese Moemoe';
			$GenreLookupSCMPX[254] = 'Japanese Tokusatsu';
			//$GenreLookupSCMPX[255] = 'Japanese Anime';
		}

		return ($allowSCMPXextended ? $GenreLookupSCMPX : $GenreLookup);
	}

	/**
	 * @param string $genreid
	 * @param bool   $allowSCMPXextended
	 *
	 * @return string|false
	 */
	public static function LookupGenreName($genreid, $allowSCMPXextended=true) {
		switch ($genreid) {
			case 'RX':
			case 'CR':
				break;
			default:
				if (!is_numeric($genreid)) {
					return false;
				}
				$genreid = intval($genreid); // to handle 3 or '3' or '03'
				break;
		}
		$GenreLookup = self::ArrayOfGenres($allowSCMPXextended);
		return (isset($GenreLookup[$genreid]) ? $GenreLookup[$genreid] : false);
	}

	/**
	 * @param string $genre
	 * @param bool   $allowSCMPXextended
	 *
	 * @return string|false
	 */
	public static function LookupGenreID($genre, $allowSCMPXextended=false) {
		$GenreLookup = self::ArrayOfGenres($allowSCMPXextended);
		$LowerCaseNoSpaceSearchTerm = strtolower(str_replace(' ', '', $genre));
		foreach ($GenreLookup as $key => $value) {
			if (strtolower(str_replace(' ', '', $value)) == $LowerCaseNoSpaceSearchTerm) {
				return $key;
			}
		}
		return false;
	}

	/**
	 * @param string $OriginalGenre
	 *
	 * @return string|false
	 */
	public static function StandardiseID3v1GenreName($OriginalGenre) {
		if (($GenreID = self::LookupGenreID($OriginalGenre)) !== false) {
			return self::LookupGenreName($GenreID);
		}
		return $OriginalGenre;
	}

	/**
	 * @param string     $title
	 * @param string     $artist
	 * @param string     $album
	 * @param string     $year
	 * @param int        $genreid
	 * @param string     $comment
	 * @param int|string $track
	 *
	 * @return string
	 */
	public static function GenerateID3v1Tag($title, $artist, $album, $year, $genreid, $comment, $track='') {
		$ID3v1Tag  = 'TAG';
		$ID3v1Tag .= str_pad(trim(substr($title,  0, 30)), 30, "\x00", STR_PAD_RIGHT);
		$ID3v1Tag .= str_pad(trim(substr($artist, 0, 30)), 30, "\x00", STR_PAD_RIGHT);
		$ID3v1Tag .= str_pad(trim(substr($album,  0, 30)), 30, "\x00", STR_PAD_RIGHT);
		$ID3v1Tag .= str_pad(trim(substr($year,   0,  4)),  4, "\x00", STR_PAD_LEFT);
		if (!empty($track) && ($track > 0) && ($track <= 255)) {
			$ID3v1Tag .= str_pad(trim(substr($comment, 0, 28)), 28, "\x00", STR_PAD_RIGHT);
			$ID3v1Tag .= "\x00";
			if (gettype($track) == 'string') {
				$track = (int) $track;
			}
			$ID3v1Tag .= chr($track);
		} else {
			$ID3v1Tag .= str_pad(trim(substr($comment, 0, 30)), 30, "\x00", STR_PAD_RIGHT);
		}
		if (($genreid < 0) || ($genreid > 147)) {
			$genreid = 255; // 'unknown' genre
		}
		switch (gettype($genreid)) {
			case 'string':
			case 'integer':
				$ID3v1Tag .= chr(intval($genreid));
				break;
			default:
				$ID3v1Tag .= chr(255); // 'unknown' genre
				break;
		}

		return $ID3v1Tag;
	}

}