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

getid3_lib::IncludeDependency(GETID3_INCLUDEPATH.'module.audio.flac.php'__FILE__true);

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

        
$info['fileformat'] = 'ogg';

        
// Warn about illegal tags - only vorbiscomments are allowed
        
if (isset($info['id3v2'])) {
            
$info['warning'][] = 'Illegal ID3v2 tag present.';
        }
        if (isset(
$info['id3v1'])) {
            
$info['warning'][] = 'Illegal ID3v1 tag present.';
        }
        if (isset(
$info['ape'])) {
            
$info['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()) {
            
$info['error'][] = 'Could not find start of Ogg page in the first '.$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($filedata04) == 'fLaC') {

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

        } elseif (
substr($filedata16) == 'vorbis') {

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

        } elseif (
substr($filedata08) == 'OpusHead') {

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

        } elseif (
substr($filedata08) == '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($filedata$filedataoffset8); // hard-coded to 'Speex   '
            
$filedataoffset += 8;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['speex_version']          =                              substr($filedata$filedataoffset20);
            
$filedataoffset += 20;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['speex_version_id']       = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
            
$filedataoffset += 4;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['header_size']            = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
            
$filedataoffset += 4;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['rate']                   = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
            
$filedataoffset += 4;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['mode']                   = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
            
$filedataoffset += 4;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['mode_bitstream_version'] = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
            
$filedataoffset += 4;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['nb_channels']            = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
            
$filedataoffset += 4;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['bitrate']                = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
            
$filedataoffset += 4;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['framesize']              = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
            
$filedataoffset += 4;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['vbr']                    = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
            
$filedataoffset += 4;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['frames_per_packet']      = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
            
$filedataoffset += 4;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['extra_headers']          = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
            
$filedataoffset += 4;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['reserved1']              = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
            
$filedataoffset += 4;
            
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['reserved2']              = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
            
$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($filedata07) == "\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'];
            }
$info['warning'][] = 'Ogg Theora (v3) not fully supported in this version of getID3 ['.$this->getid3->version().'] -- bitrate, playtime and all audio data are currently unavailable';


        } elseif (
substr($filedata08) == "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$filedataoffset20));
            
$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($filedata08) == "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($filedata16) == 'theora') {

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

                
} elseif (substr($filedata16) == 'vorbis') {

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

                } else {
                    
$info['error'][] = 'unexpected';
                    
//break;
                
}
            
//} while ($oggpageinfo['page_seqno'] == 0);
            
} while (($oggpageinfo['page_seqno'] == 0) && (substr($filedata08) != "fisbone\x00"));

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

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

        
} else {

            
$info['error'][] = 'Expecting either "Speex   ", "OpusHead" or "vorbis" identifier strings, found "'.substr($filedata08).'"';
            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($filedata01));
                
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['stream_type'] =                              substr($filedata16); // hard-coded to 'vorbis'

                
$this->ParseVorbisComments();
                break;

            case 
'flac':
                
$flac = new getid3_flac($this->getid3);
                if (!
$flac->parseMETAdata()) {
                    
$info['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($filedata08); // hard-coded to 'OpusTags'
                
if(substr($filedata08)  != 'OpusTags') {
                    
$info['error'][] = 'Expected "OpusTags" as header but got "'.substr($filedata08).'"';
                    return 
false;
                }

                
$this->ParseVorbisComments();
                break;

        }

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

            
$info['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) {
                    
$info['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) {
                
$info['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;
    }

    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($filedata$filedataoffset1));
        
$filedataoffset += 1;
        
$info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['stream_type'] = substr($filedata$filedataoffset6); // hard-coded to 'vorbis'
        
$filedataoffset += 6;
        
$info['ogg']['bitstreamversion'] = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
        
$filedataoffset += 4;
        
$info['ogg']['numberofchannels'] = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset1));
        
$filedataoffset += 1;
        
$info['audio']['channels']       = $info['ogg']['numberofchannels'];
        
$info['ogg']['samplerate']       = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
        
$filedataoffset += 4;
        if (
$info['ogg']['samplerate'] == 0) {
            
$info['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$filedataoffset4));
        
$filedataoffset += 4;
        
$info['ogg']['bitrate_nominal']  = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
        
$filedataoffset += 4;
        
$info['ogg']['bitrate_min']      = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
        
$filedataoffset += 4;
        
$info['ogg']['blocksize_small']  = pow(2,  getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset1)) & 0x0F);
        
$info['ogg']['blocksize_large']  = pow(2, (getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset1)) & 0xF0) >> 4);
        
$info['ogg']['stop_bit']         = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset1)); // 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;
    }

    
// http://tools.ietf.org/html/draft-ietf-codec-oggopus-03
    
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$filedataoffset8); // 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'] < || $info['ogg']['pageheader']['opus']['version'] > 15) {
            
$info['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) {
            
$info['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;

        
$info['ogg']['pageheader']['opus']['sample_rate'] = getid3_lib::LittleEndian2Int(substr($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']       = $info['ogg']['pageheader']['opus']['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']   = $info['opus']['sample_rate'];
        return 
true;
    }


    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())) === false)) {
                    
// 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$filedataoffset1));
        
$filedataoffset += 1;
        
$oggheader['flags_raw']         = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset1));
        
$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$filedataoffset8));
        
$filedataoffset += 8;
        
$oggheader['stream_serialno']   = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
        
$filedataoffset += 4;
        
$oggheader['page_seqno']        = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
        
$filedataoffset += 4;
        
$oggheader['page_checksum']     = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset4));
        
$filedataoffset += 4;
        
$oggheader['page_segments']     = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset1));
        
$filedataoffset += 1;
        
$oggheader['page_length'] = 0;
        for (
$i 0$i $oggheader['page_segments']; $i++) {
            
$oggheader['segment_table'][$i] = getid3_lib::LittleEndian2Int(substr($filedata$filedataoffset1));
            
$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;
    }

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

        
$OriginalOffset $this->ftell();
        
$commentdataoffset 0;
        
$VorbisCommentPage 1;

        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;
                break;
        }

        
$VendorSize getid3_lib::LittleEndian2Int(substr($commentdata$commentdataoffset4));
        
$commentdataoffset += 4;

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

        
$CommentsCount getid3_lib::LittleEndian2Int(substr($commentdata$commentdataoffset4));
        
$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
                
$info['warning'][] = 'Unexpectedly large number ('.$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
                    
$commentdata     substr($commentdata0$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($commentdata$commentdataoffset4));

            
// 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)) {
                    
$info['warning'][] = 'Invalid Ogg comment size (comment #'.$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
                
$commentdata     substr($commentdata0$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])) {
                    
$info['warning'][] = 'undefined Vorbis Comment page "'.$VorbisCommentPage.'" at offset '.$this->ftell();
                    break;
                }
                
$readlength self::OggPageSegmentLength($info['ogg']['pageheader'][$VorbisCommentPage], 1);
                if (
$readlength <= 0) {
                    
$info['warning'][] = 'invalid length Vorbis Comment page "'.$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?
                
$info['warning'][] = 'Blank Ogg comment ['.$i.']';

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

                
$commentexploded explode('='$commentstring2);
                
$ThisFileInfo_ogg_comments_raw[$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'         => $ogg->saveAttachment('coverart'0strlen($data), $imageinfo['mime']),
                    );
                    unset(
$ogg);

                } else {

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

                }

            } else {

                
$info['warning'][] = '[known problem with CDex >= v1.40, < v1.50b7] Invalid Ogg comment name/value pair ['.$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;
    }

    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);
    }


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


    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($qval1); // 5 or 4.9
    
}

    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);
    }

    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);
    }

}