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[autoinstallsdev/mediawiki.git] / vendor / james-heinrich / getid3 / getid3 / module.audio.ogg.php
diff --git a/vendor/james-heinrich/getid3/getid3/module.audio.ogg.php b/vendor/james-heinrich/getid3/getid3/module.audio.ogg.php
new file mode 100644 (file)
index 0000000..e41c96c
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@@ -0,0 +1,840 @@
+<?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'])) {
+                       $this->warning('Illegal ID3v2 tag present.');
+               }
+               if (isset($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;
+
+               } else {
+
+                       $this->error('Expecting either "Speex   ", "OpusHead" or "vorbis" identifier strings, found "'.substr($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;
+       }
+
+       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']);
+                       $info['audio']['bitrate_mode'] = 'abr';
+               }
+               return true;
+       }
+
+       // http://tools.ietf.org/html/draft-ietf-codec-oggopus-03
+       public function ParseOpusPageHeader(&$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, $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;
+
+               $info['ogg']['pageheader']['opus']['sample_rate'] = getid3_lib::LittleEndian2Int(substr($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, $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;
+       }
+
+    // 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, $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;
+       }
+
+       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($qval, 1); // 5 or 4.9
+       }
+
+       public static function TheoraColorSpace($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);
+       }
+
+}