Initial commit

1 files changed, 682 insertions, 0 deletions

diff --git a/includes/getid3/module.audio-video.mpeg.php b/includes/getid3/module.audio-video.mpeg.php
new file mode 100644
index 0000000..5ca4120
--- /dev/null
+++ b/includes/getid3/module.audio-video.mpeg.php
@@ -0,0 +1,682 @@
+<?php
+
+/////////////////////////////////////////////////////////////////
+/// getID3() by James Heinrich <info@getid3.org>               //
+//  available at https://github.com/JamesHeinrich/getID3       //
+//            or https://www.getid3.org                        //
+//            or http://getid3.sourceforge.net                 //
+//  see readme.txt for more details                            //
+/////////////////////////////////////////////////////////////////
+//                                                             //
+// module.audio-video.mpeg.php                                 //
+// module for analyzing MPEG files                             //
+// dependencies: module.audio.mp3.php                          //
+//                                                            ///
+/////////////////////////////////////////////////////////////////
+
+if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers
+	exit;
+}
+getid3_lib::IncludeDependency(GETID3_INCLUDEPATH.'module.audio.mp3.php', __FILE__, true);
+
+class getid3_mpeg extends getid3_handler
+{
+
+	const START_CODE_BASE       = "\x00\x00\x01";
+	const VIDEO_PICTURE_START   = "\x00\x00\x01\x00";
+	const VIDEO_USER_DATA_START = "\x00\x00\x01\xB2";
+	const VIDEO_SEQUENCE_HEADER = "\x00\x00\x01\xB3";
+	const VIDEO_SEQUENCE_ERROR  = "\x00\x00\x01\xB4";
+	const VIDEO_EXTENSION_START = "\x00\x00\x01\xB5";
+	const VIDEO_SEQUENCE_END    = "\x00\x00\x01\xB7";
+	const VIDEO_GROUP_START     = "\x00\x00\x01\xB8";
+	const AUDIO_START           = "\x00\x00\x01\xC0";
+
+	/**
+	 * @return bool
+	 */
+	public function Analyze() {
+		$info = &$this->getid3->info;
+
+		$info['fileformat'] = 'mpeg';
+		$this->fseek($info['avdataoffset']);
+
+		$MPEGstreamData = $this->fread($this->getid3->option_fread_buffer_size);
+		$MPEGstreamBaseOffset = 0; // how far are we from the beginning of the file data ($info['avdataoffset'])
+		$MPEGstreamDataOffset = 0; // how far are we from the beginning of the buffer data (~32kB)
+
+		$StartCodeValue     = false;
+		$prevStartCodeValue = false;
+
+		$GOPcounter = -1;
+		$FramesByGOP = array();
+		$ParsedAVchannels = array();
+
+		do {
+//echo $MPEGstreamDataOffset.' vs '.(strlen($MPEGstreamData) - 1024).'<Br>';
+			if ($MPEGstreamDataOffset > (strlen($MPEGstreamData) - 16384)) {
+				// buffer running low, get more data
+//echo 'reading more data<br>';
+				$MPEGstreamData .= $this->fread($this->getid3->option_fread_buffer_size);
+				if (strlen($MPEGstreamData) > $this->getid3->option_fread_buffer_size) {
+					$MPEGstreamData = substr($MPEGstreamData, $MPEGstreamDataOffset);
+					$MPEGstreamBaseOffset += $MPEGstreamDataOffset;
+					$MPEGstreamDataOffset  = 0;
+				}
+			}
+			if (($StartCodeOffset = strpos($MPEGstreamData, self::START_CODE_BASE, $MPEGstreamDataOffset)) === false) {
+//echo 'no more start codes found.<br>';
+				break;
+			} else {
+				$MPEGstreamDataOffset = $StartCodeOffset;
+				$prevStartCodeValue = $StartCodeValue;
+				$StartCodeValue = ord(substr($MPEGstreamData, $StartCodeOffset + 3, 1));
+//echo 'Found "'.strtoupper(dechex($StartCodeValue)).'" at offset '.($MPEGstreamBaseOffset + $StartCodeOffset).' ($MPEGstreamDataOffset = '.$MPEGstreamDataOffset.')<br>';
+			}
+			$MPEGstreamDataOffset += 4;
+			switch ($StartCodeValue) {
+
+				case 0x00: // picture_start_code
+					if (!empty($info['mpeg']['video']['bitrate_mode']) && ($info['mpeg']['video']['bitrate_mode'] == 'vbr')) {
+						$bitstream = getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 4, 4));
+						$bitstreamoffset = 0;
+
+						$PictureHeader = array();
+
+						$PictureHeader['temporal_reference']  = self::readBitsFromStream($bitstream, $bitstreamoffset, 10); // 10-bit unsigned integer associated with each input picture. It is incremented by one, modulo 1024, for each input frame. When a frame is coded as two fields the temporal reference in the picture header of both fields is the same. Following a group start header the temporal reference of the earliest picture (in display order) shall be reset to zero.
+						$PictureHeader['picture_coding_type'] = self::readBitsFromStream($bitstream, $bitstreamoffset,  3); //  3 bits for picture_coding_type
+						$PictureHeader['vbv_delay']           = self::readBitsFromStream($bitstream, $bitstreamoffset, 16); // 16 bits for vbv_delay
+						//... etc
+
+						$FramesByGOP[$GOPcounter][] = $PictureHeader;
+					}
+					break;
+
+				case 0xB3: // sequence_header_code
+					// Note: purposely doing the less-pretty (and probably a bit slower) method of using string of bits rather than bitwise operations.
+					// Mostly because PHP 32-bit doesn't handle unsigned integers well for bitwise operation.
+					// Also the MPEG stream is designed as a bitstream and often doesn't align nicely with byte boundaries.
+					$info['video']['codec'] = 'MPEG-1'; // will be updated if extension_start_code found
+
+					$bitstream = getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 4, 8));
+					$bitstreamoffset = 0;
+
+					$info['mpeg']['video']['raw']['horizontal_size_value']       = self::readBitsFromStream($bitstream, $bitstreamoffset, 12); // 12 bits for horizontal frame size. Note: horizontal_size_extension, if present, will add 2 most-significant bits to this value
+					$info['mpeg']['video']['raw']['vertical_size_value']         = self::readBitsFromStream($bitstream, $bitstreamoffset, 12); // 12 bits for vertical frame size.   Note: vertical_size_extension,   if present, will add 2 most-significant bits to this value
+					$info['mpeg']['video']['raw']['aspect_ratio_information']    = self::readBitsFromStream($bitstream, $bitstreamoffset,  4); //  4 bits for aspect_ratio_information
+					$info['mpeg']['video']['raw']['frame_rate_code']             = self::readBitsFromStream($bitstream, $bitstreamoffset,  4); //  4 bits for Frame Rate id code
+					$info['mpeg']['video']['raw']['bitrate']                     = self::readBitsFromStream($bitstream, $bitstreamoffset, 18); // 18 bits for bit_rate_value (18 set bits = VBR, otherwise bitrate = this value * 400)
+					$marker_bit                                                  = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // The term "marker_bit" indicates a one bit field in which the value zero is forbidden. These marker bits are introduced at several points in the syntax to avoid start code emulation.
+					$info['mpeg']['video']['raw']['vbv_buffer_size']             = self::readBitsFromStream($bitstream, $bitstreamoffset, 10); // 10 bits vbv_buffer_size_value
+					$info['mpeg']['video']['raw']['constrained_param_flag']      = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: constrained_param_flag
+					$info['mpeg']['video']['raw']['load_intra_quantiser_matrix'] = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: load_intra_quantiser_matrix
+
+					if ($info['mpeg']['video']['raw']['load_intra_quantiser_matrix']) {
+						$bitstream .= getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 12, 64));
+						for ($i = 0; $i < 64; $i++) {
+							$info['mpeg']['video']['raw']['intra_quantiser_matrix'][$i] = self::readBitsFromStream($bitstream, $bitstreamoffset,  8);
+						}
+					}
+					$info['mpeg']['video']['raw']['load_non_intra_quantiser_matrix'] = self::readBitsFromStream($bitstream, $bitstreamoffset,  1);
+
+					if ($info['mpeg']['video']['raw']['load_non_intra_quantiser_matrix']) {
+						$bitstream .= getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 12 + ($info['mpeg']['video']['raw']['load_intra_quantiser_matrix'] ? 64 : 0), 64));
+						for ($i = 0; $i < 64; $i++) {
+							$info['mpeg']['video']['raw']['non_intra_quantiser_matrix'][$i] = self::readBitsFromStream($bitstream, $bitstreamoffset,  8);
+						}
+					}
+
+					$info['mpeg']['video']['pixel_aspect_ratio']      =     self::videoAspectRatioLookup($info['mpeg']['video']['raw']['aspect_ratio_information']); // may be overridden later if file turns out to be MPEG-2
+					$info['mpeg']['video']['pixel_aspect_ratio_text'] = self::videoAspectRatioTextLookup($info['mpeg']['video']['raw']['aspect_ratio_information']); // may be overridden later if file turns out to be MPEG-2
+					$info['mpeg']['video']['frame_rate']              =       self::videoFramerateLookup($info['mpeg']['video']['raw']['frame_rate_code']);
+					if ($info['mpeg']['video']['raw']['bitrate'] == 0x3FFFF) { // 18 set bits = VBR
+						//$this->warning('This version of getID3() ['.$this->getid3->version().'] cannot determine average bitrate of VBR MPEG video files');
+						$info['mpeg']['video']['bitrate_mode'] = 'vbr';
+					} else {
+						$info['mpeg']['video']['bitrate']      = $info['mpeg']['video']['raw']['bitrate'] * 400;
+						$info['mpeg']['video']['bitrate_mode'] = 'cbr';
+						$info['video']['bitrate']              = $info['mpeg']['video']['bitrate'];
+					}
+					$info['video']['resolution_x']       = $info['mpeg']['video']['raw']['horizontal_size_value'];
+					$info['video']['resolution_y']       = $info['mpeg']['video']['raw']['vertical_size_value'];
+					$info['video']['frame_rate']         = $info['mpeg']['video']['frame_rate'];
+					$info['video']['bitrate_mode']       = $info['mpeg']['video']['bitrate_mode'];
+					$info['video']['pixel_aspect_ratio'] = $info['mpeg']['video']['pixel_aspect_ratio'];
+					$info['video']['lossless']           = false;
+					$info['video']['bits_per_sample']    = 24;
+					break;
+
+				case 0xB5: // extension_start_code
+					$info['video']['codec'] = 'MPEG-2';
+
+					$bitstream = getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 4, 8)); // 48 bits for Sequence Extension ID; 61 bits for Sequence Display Extension ID; 59 bits for Sequence Scalable Extension ID
+					$bitstreamoffset = 0;
+
+					$info['mpeg']['video']['raw']['extension_start_code_identifier'] = self::readBitsFromStream($bitstream, $bitstreamoffset,  4); //  4 bits for extension_start_code_identifier
+//echo $info['mpeg']['video']['raw']['extension_start_code_identifier'].'<br>';
+					switch ($info['mpeg']['video']['raw']['extension_start_code_identifier']) {
+						case  1: // 0001 Sequence Extension ID
+							$info['mpeg']['video']['raw']['profile_and_level_indication']    = self::readBitsFromStream($bitstream, $bitstreamoffset,  8); //  8 bits for profile_and_level_indication
+							$info['mpeg']['video']['raw']['progressive_sequence']            = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: progressive_sequence
+							$info['mpeg']['video']['raw']['chroma_format']                   = self::readBitsFromStream($bitstream, $bitstreamoffset,  2); //  2 bits for chroma_format
+							$info['mpeg']['video']['raw']['horizontal_size_extension']       = self::readBitsFromStream($bitstream, $bitstreamoffset,  2); //  2 bits for horizontal_size_extension
+							$info['mpeg']['video']['raw']['vertical_size_extension']         = self::readBitsFromStream($bitstream, $bitstreamoffset,  2); //  2 bits for vertical_size_extension
+							$info['mpeg']['video']['raw']['bit_rate_extension']              = self::readBitsFromStream($bitstream, $bitstreamoffset, 12); // 12 bits for bit_rate_extension
+							$marker_bit                                                      = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // The term "marker_bit" indicates a one bit field in which the value zero is forbidden. These marker bits are introduced at several points in the syntax to avoid start code emulation.
+							$info['mpeg']['video']['raw']['vbv_buffer_size_extension']       = self::readBitsFromStream($bitstream, $bitstreamoffset,  8); //  8 bits for vbv_buffer_size_extension
+							$info['mpeg']['video']['raw']['low_delay']                       = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: low_delay
+							$info['mpeg']['video']['raw']['frame_rate_extension_n']          = self::readBitsFromStream($bitstream, $bitstreamoffset,  2); //  2 bits for frame_rate_extension_n
+							$info['mpeg']['video']['raw']['frame_rate_extension_d']          = self::readBitsFromStream($bitstream, $bitstreamoffset,  5); //  5 bits for frame_rate_extension_d
+
+							$info['video']['resolution_x']          = ($info['mpeg']['video']['raw']['horizontal_size_extension'] << 12) | $info['mpeg']['video']['raw']['horizontal_size_value'];
+							$info['video']['resolution_y']          = ($info['mpeg']['video']['raw']['vertical_size_extension']   << 12) | $info['mpeg']['video']['raw']['vertical_size_value'];
+							$info['video']['interlaced']            = !$info['mpeg']['video']['raw']['progressive_sequence'];
+							$info['mpeg']['video']['interlaced']    = !$info['mpeg']['video']['raw']['progressive_sequence'];
+							$info['mpeg']['video']['chroma_format'] = self::chromaFormatTextLookup($info['mpeg']['video']['raw']['chroma_format']);
+
+							if (isset($info['mpeg']['video']['raw']['aspect_ratio_information'])) {
+								// MPEG-2 defines the aspect ratio flag differently from MPEG-1, but the MPEG-2 extension start code may occur after we've already looked up the aspect ratio assuming it was MPEG-1, so re-lookup assuming MPEG-2
+								// This must be done after the extended size is known, so the display aspect ratios can be converted to pixel aspect ratios.
+								$info['mpeg']['video']['pixel_aspect_ratio']      =     self::videoAspectRatioLookup($info['mpeg']['video']['raw']['aspect_ratio_information'], 2, $info['video']['resolution_x'], $info['video']['resolution_y']);
+								$info['mpeg']['video']['pixel_aspect_ratio_text'] = self::videoAspectRatioTextLookup($info['mpeg']['video']['raw']['aspect_ratio_information'], 2);
+								$info['video']['pixel_aspect_ratio'] = $info['mpeg']['video']['pixel_aspect_ratio'];
+								$info['video']['pixel_aspect_ratio_text'] = $info['mpeg']['video']['pixel_aspect_ratio_text'];
+							}
+
+							break;
+
+						case  2: // 0010 Sequence Display Extension ID
+							$info['mpeg']['video']['raw']['video_format']                    = self::readBitsFromStream($bitstream, $bitstreamoffset,  3); //  3 bits for video_format
+							$info['mpeg']['video']['raw']['colour_description']              = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: colour_description
+							if ($info['mpeg']['video']['raw']['colour_description']) {
+								$info['mpeg']['video']['raw']['colour_primaries']            = self::readBitsFromStream($bitstream, $bitstreamoffset,  8); //  8 bits for colour_primaries
+								$info['mpeg']['video']['raw']['transfer_characteristics']    = self::readBitsFromStream($bitstream, $bitstreamoffset,  8); //  8 bits for transfer_characteristics
+								$info['mpeg']['video']['raw']['matrix_coefficients']         = self::readBitsFromStream($bitstream, $bitstreamoffset,  8); //  8 bits for matrix_coefficients
+							}
+							$info['mpeg']['video']['raw']['display_horizontal_size']         = self::readBitsFromStream($bitstream, $bitstreamoffset, 14); // 14 bits for display_horizontal_size
+							$marker_bit                                                      = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // The term "marker_bit" indicates a one bit field in which the value zero is forbidden. These marker bits are introduced at several points in the syntax to avoid start code emulation.
+							$info['mpeg']['video']['raw']['display_vertical_size']           = self::readBitsFromStream($bitstream, $bitstreamoffset, 14); // 14 bits for display_vertical_size
+
+							$info['mpeg']['video']['video_format'] = self::videoFormatTextLookup($info['mpeg']['video']['raw']['video_format']);
+							break;
+
+						case  3: // 0011 Quant Matrix Extension ID
+							break;
+
+						case  5: // 0101 Sequence Scalable Extension ID
+							$info['mpeg']['video']['raw']['scalable_mode']                              = self::readBitsFromStream($bitstream, $bitstreamoffset,  2); //  2 bits for scalable_mode
+							$info['mpeg']['video']['raw']['layer_id']                                   = self::readBitsFromStream($bitstream, $bitstreamoffset,  4); //  4 bits for layer_id
+							if ($info['mpeg']['video']['raw']['scalable_mode'] == 1) { // "spatial scalability"
+								$info['mpeg']['video']['raw']['lower_layer_prediction_horizontal_size'] = self::readBitsFromStream($bitstream, $bitstreamoffset, 14); // 14 bits for lower_layer_prediction_horizontal_size
+								$marker_bit                                                             = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // The term "marker_bit" indicates a one bit field in which the value zero is forbidden. These marker bits are introduced at several points in the syntax to avoid start code emulation.
+								$info['mpeg']['video']['raw']['lower_layer_prediction_vertical_size']   = self::readBitsFromStream($bitstream, $bitstreamoffset, 14); // 14 bits for lower_layer_prediction_vertical_size
+								$info['mpeg']['video']['raw']['horizontal_subsampling_factor_m']        = self::readBitsFromStream($bitstream, $bitstreamoffset,  5); //  5 bits for horizontal_subsampling_factor_m
+								$info['mpeg']['video']['raw']['horizontal_subsampling_factor_n']        = self::readBitsFromStream($bitstream, $bitstreamoffset,  5); //  5 bits for horizontal_subsampling_factor_n
+								$info['mpeg']['video']['raw']['vertical_subsampling_factor_m']          = self::readBitsFromStream($bitstream, $bitstreamoffset,  5); //  5 bits for vertical_subsampling_factor_m
+								$info['mpeg']['video']['raw']['vertical_subsampling_factor_n']          = self::readBitsFromStream($bitstream, $bitstreamoffset,  5); //  5 bits for vertical_subsampling_factor_n
+							} elseif ($info['mpeg']['video']['raw']['scalable_mode'] == 3) { // "temporal scalability"
+								$info['mpeg']['video']['raw']['picture_mux_enable']                     = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: picture_mux_enable
+								if ($info['mpeg']['video']['raw']['picture_mux_enable']) {
+									$info['mpeg']['video']['raw']['mux_to_progressive_sequence']        = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: mux_to_progressive_sequence
+								}
+								$info['mpeg']['video']['raw']['picture_mux_order']                      = self::readBitsFromStream($bitstream, $bitstreamoffset,  3); //  3 bits for picture_mux_order
+								$info['mpeg']['video']['raw']['picture_mux_factor']                     = self::readBitsFromStream($bitstream, $bitstreamoffset,  3); //  3 bits for picture_mux_factor
+							}
+
+							$info['mpeg']['video']['scalable_mode'] = self::scalableModeTextLookup($info['mpeg']['video']['raw']['scalable_mode']);
+							break;
+
+						case  7: // 0111 Picture Display Extension ID
+							break;
+
+						case  8: // 1000 Picture Coding Extension ID
+							$info['mpeg']['video']['raw']['f_code_00']                       = self::readBitsFromStream($bitstream, $bitstreamoffset,  4); // 4 bits for f_code[0][0] (forward horizontal)
+							$info['mpeg']['video']['raw']['f_code_01']                       = self::readBitsFromStream($bitstream, $bitstreamoffset,  4); // 4 bits for f_code[0][1] (forward vertical)
+							$info['mpeg']['video']['raw']['f_code_10']                       = self::readBitsFromStream($bitstream, $bitstreamoffset,  4); // 4 bits for f_code[1][0] (backward horizontal)
+							$info['mpeg']['video']['raw']['f_code_11']                       = self::readBitsFromStream($bitstream, $bitstreamoffset,  4); // 4 bits for f_code[1][1] (backward vertical)
+							$info['mpeg']['video']['raw']['intra_dc_precision']              = self::readBitsFromStream($bitstream, $bitstreamoffset,  2); // 2 bits for intra_dc_precision
+							$info['mpeg']['video']['raw']['picture_structure']               = self::readBitsFromStream($bitstream, $bitstreamoffset,  2); // 2 bits for picture_structure
+							$info['mpeg']['video']['raw']['top_field_first']                 = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // 1 bit flag: top_field_first
+							$info['mpeg']['video']['raw']['frame_pred_frame_dct']            = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // 1 bit flag: frame_pred_frame_dct
+							$info['mpeg']['video']['raw']['concealment_motion_vectors']      = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // 1 bit flag: concealment_motion_vectors
+							$info['mpeg']['video']['raw']['q_scale_type']                    = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // 1 bit flag: q_scale_type
+							$info['mpeg']['video']['raw']['intra_vlc_format']                = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // 1 bit flag: intra_vlc_format
+							$info['mpeg']['video']['raw']['alternate_scan']                  = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // 1 bit flag: alternate_scan
+							$info['mpeg']['video']['raw']['repeat_first_field']              = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // 1 bit flag: repeat_first_field
+							$info['mpeg']['video']['raw']['chroma_420_type']                 = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // 1 bit flag: chroma_420_type
+							$info['mpeg']['video']['raw']['progressive_frame']               = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // 1 bit flag: progressive_frame
+							$info['mpeg']['video']['raw']['composite_display_flag']          = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // 1 bit flag: composite_display_flag
+							if ($info['mpeg']['video']['raw']['composite_display_flag']) {
+								$info['mpeg']['video']['raw']['v_axis']                      = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // 1 bit flag: v_axis
+								$info['mpeg']['video']['raw']['field_sequence']              = self::readBitsFromStream($bitstream, $bitstreamoffset,  3); // 3 bits for field_sequence
+								$info['mpeg']['video']['raw']['sub_carrier']                 = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // 1 bit flag: sub_carrier
+								$info['mpeg']['video']['raw']['burst_amplitude']             = self::readBitsFromStream($bitstream, $bitstreamoffset,  7); // 7 bits for burst_amplitude
+								$info['mpeg']['video']['raw']['sub_carrier_phase']           = self::readBitsFromStream($bitstream, $bitstreamoffset,  8); // 8 bits for sub_carrier_phase
+							}
+
+							$info['mpeg']['video']['intra_dc_precision_bits'] = $info['mpeg']['video']['raw']['intra_dc_precision'] + 8;
+							$info['mpeg']['video']['picture_structure'] = self::pictureStructureTextLookup($info['mpeg']['video']['raw']['picture_structure']);
+							break;
+
+						case  9: // 1001 Picture Spatial Scalable Extension ID
+							break;
+						case 10: // 1010 Picture Temporal Scalable Extension ID
+							break;
+
+						default:
+							$this->warning('Unexpected $info[mpeg][video][raw][extension_start_code_identifier] value of '.$info['mpeg']['video']['raw']['extension_start_code_identifier']);
+							break;
+					}
+					break;
+
+
+				case 0xB8: // group_of_pictures_header
+					$GOPcounter++;
+					if (!empty($info['mpeg']['video']['bitrate_mode']) && ($info['mpeg']['video']['bitrate_mode'] == 'vbr')) {
+						$bitstream = getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 4, 4)); // 27 bits needed for group_of_pictures_header
+						$bitstreamoffset = 0;
+
+						$GOPheader = array();
+
+						$GOPheader['byte_offset'] = $MPEGstreamBaseOffset + $StartCodeOffset;
+						$GOPheader['drop_frame_flag']    = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: drop_frame_flag
+						$GOPheader['time_code_hours']    = self::readBitsFromStream($bitstream, $bitstreamoffset,  5); //  5 bits for time_code_hours
+						$GOPheader['time_code_minutes']  = self::readBitsFromStream($bitstream, $bitstreamoffset,  6); //  6 bits for time_code_minutes
+						$marker_bit                      = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); // The term "marker_bit" indicates a one bit field in which the value zero is forbidden. These marker bits are introduced at several points in the syntax to avoid start code emulation.
+						$GOPheader['time_code_seconds']  = self::readBitsFromStream($bitstream, $bitstreamoffset,  6); //  6 bits for time_code_seconds
+						$GOPheader['time_code_pictures'] = self::readBitsFromStream($bitstream, $bitstreamoffset,  6); //  6 bits for time_code_pictures
+						$GOPheader['closed_gop']         = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: closed_gop
+						$GOPheader['broken_link']        = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: broken_link
+
+						$time_code_separator = ($GOPheader['drop_frame_flag'] ? ';' : ':'); // While non-drop time code is displayed with colons separating the digit pairs "HH:MM:SS:FF" drop frame is usually represented with a semi-colon (;) or period (.) as the divider between all the digit pairs "HH;MM;SS;FF", "HH.MM.SS.FF"
+						$GOPheader['time_code'] = sprintf('%02d'.$time_code_separator.'%02d'.$time_code_separator.'%02d'.$time_code_separator.'%02d', $GOPheader['time_code_hours'], $GOPheader['time_code_minutes'], $GOPheader['time_code_seconds'], $GOPheader['time_code_pictures']);
+
+						$info['mpeg']['group_of_pictures'][] = $GOPheader;
+					}
+					break;
+
+				case 0xC0: // audio stream
+				case 0xC1: // audio stream
+				case 0xC2: // audio stream
+				case 0xC3: // audio stream
+				case 0xC4: // audio stream
+				case 0xC5: // audio stream
+				case 0xC6: // audio stream
+				case 0xC7: // audio stream
+				case 0xC8: // audio stream
+				case 0xC9: // audio stream
+				case 0xCA: // audio stream
+				case 0xCB: // audio stream
+				case 0xCC: // audio stream
+				case 0xCD: // audio stream
+				case 0xCE: // audio stream
+				case 0xCF: // audio stream
+				case 0xD0: // audio stream
+				case 0xD1: // audio stream
+				case 0xD2: // audio stream
+				case 0xD3: // audio stream
+				case 0xD4: // audio stream
+				case 0xD5: // audio stream
+				case 0xD6: // audio stream
+				case 0xD7: // audio stream
+				case 0xD8: // audio stream
+				case 0xD9: // audio stream
+				case 0xDA: // audio stream
+				case 0xDB: // audio stream
+				case 0xDC: // audio stream
+				case 0xDD: // audio stream
+				case 0xDE: // audio stream
+				case 0xDF: // audio stream
+				//case 0xE0: // video stream
+				//case 0xE1: // video stream
+				//case 0xE2: // video stream
+				//case 0xE3: // video stream
+				//case 0xE4: // video stream
+				//case 0xE5: // video stream
+				//case 0xE6: // video stream
+				//case 0xE7: // video stream
+				//case 0xE8: // video stream
+				//case 0xE9: // video stream
+				//case 0xEA: // video stream
+				//case 0xEB: // video stream
+				//case 0xEC: // video stream
+				//case 0xED: // video stream
+				//case 0xEE: // video stream
+				//case 0xEF: // video stream
+					if (isset($ParsedAVchannels[$StartCodeValue])) {
+						break;
+					}
+					$ParsedAVchannels[$StartCodeValue] = $StartCodeValue;
+					// http://en.wikipedia.org/wiki/Packetized_elementary_stream
+					// http://dvd.sourceforge.net/dvdinfo/pes-hdr.html
+/*
+					$PackedElementaryStream = array();
+					if ($StartCodeValue >= 0xE0) {
+						$PackedElementaryStream['stream_type'] = 'video';
+						$PackedElementaryStream['stream_id']   = $StartCodeValue - 0xE0;
+					} else {
+						$PackedElementaryStream['stream_type'] = 'audio';
+						$PackedElementaryStream['stream_id']   = $StartCodeValue - 0xC0;
+					}
+					$PackedElementaryStream['packet_length'] = getid3_lib::BigEndian2Int(substr($MPEGstreamData, $StartCodeOffset + 4, 2));
+
+					$bitstream = getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 6, 3)); // more may be needed below
+					$bitstreamoffset = 0;
+
+					$PackedElementaryStream['marker_bits']               = self::readBitsFromStream($bitstream, $bitstreamoffset,  2); //  2 bits for marker_bits -- should be "10" = 2
+echo 'marker_bits = '.$PackedElementaryStream['marker_bits'].'<br>';
+					$PackedElementaryStream['scrambling_control']        = self::readBitsFromStream($bitstream, $bitstreamoffset,  2); //  2 bits for scrambling_control -- 00 implies not scrambled
+					$PackedElementaryStream['priority']                  = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: priority
+					$PackedElementaryStream['data_alignment_indicator']  = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: data_alignment_indicator -- 1 indicates that the PES packet header is immediately followed by the video start code or audio syncword
+					$PackedElementaryStream['copyright']                 = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: copyright -- 1 implies copyrighted
+					$PackedElementaryStream['original_or_copy']          = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: original_or_copy -- 1 implies original
+					$PackedElementaryStream['pts_flag']                  = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: pts_flag -- Presentation Time Stamp
+					$PackedElementaryStream['dts_flag']                  = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: dts_flag -- Decode Time Stamp
+					$PackedElementaryStream['escr_flag']                 = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: escr_flag -- Elementary Stream Clock Reference
+					$PackedElementaryStream['es_rate_flag']              = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: es_rate_flag -- Elementary Stream [data] Rate
+					$PackedElementaryStream['dsm_trick_mode_flag']       = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: dsm_trick_mode_flag -- DSM trick mode - not used by DVD
+					$PackedElementaryStream['additional_copy_info_flag'] = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: additional_copy_info_flag
+					$PackedElementaryStream['crc_flag']                  = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: crc_flag
+					$PackedElementaryStream['extension_flag']            = self::readBitsFromStream($bitstream, $bitstreamoffset,  1); //  1 bit flag: extension_flag
+					$PackedElementaryStream['pes_remain_header_length']  = self::readBitsFromStream($bitstream, $bitstreamoffset,  8); //  1 bit flag: priority
+
+					$additional_header_bytes = 0;
+					$additional_header_bytes += ($PackedElementaryStream['pts_flag']                  ? 5 : 0);
+					$additional_header_bytes += ($PackedElementaryStream['dts_flag']                  ? 5 : 0);
+					$additional_header_bytes += ($PackedElementaryStream['escr_flag']                 ? 6 : 0);
+					$additional_header_bytes += ($PackedElementaryStream['es_rate_flag']              ? 3 : 0);
+					$additional_header_bytes += ($PackedElementaryStream['additional_copy_info_flag'] ? 1 : 0);
+					$additional_header_bytes += ($PackedElementaryStream['crc_flag']                  ? 2 : 0);
+					$additional_header_bytes += ($PackedElementaryStream['extension_flag']            ? 1 : 0);
+$PackedElementaryStream['additional_header_bytes'] = $additional_header_bytes;
+					$bitstream .= getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $StartCodeOffset + 9, $additional_header_bytes));
+
+					$info['mpeg']['packed_elementary_streams'][$PackedElementaryStream['stream_type']][$PackedElementaryStream['stream_id']][] = $PackedElementaryStream;
+*/
+					$getid3_temp = new getID3();
+					$getid3_temp->openfile($this->getid3->filename, $this->getid3->info['filesize'], $this->getid3->fp);
+					$getid3_temp->info = $info;
+					$getid3_mp3 = new getid3_mp3($getid3_temp);
+					for ($i = 0; $i <= 7; $i++) {
+						// some files have the MPEG-audio header 8 bytes after the end of the $00 $00 $01 $C0 signature, some have it up to 13 bytes (or more?) after
+						// I have no idea why or what the difference is, so this is a stupid hack.
+						// If anybody has any better idea of what's going on, please let me know - info@getid3.org
+						$getid3_temp->info = $info; // only overwrite real data if valid header found
+//echo 'audio at? '.($MPEGstreamBaseOffset + $StartCodeOffset + 4 + 8 + $i).'<br>';
+						if ($getid3_mp3->decodeMPEGaudioHeader($MPEGstreamBaseOffset + $StartCodeOffset + 4 + 8 + $i, $getid3_temp->info, false)) {
+//echo 'yes!<br>';
+							$info = $getid3_temp->info;
+							$info['audio']['bitrate_mode'] = 'cbr';
+							$info['audio']['lossless']     = false;
+							break;
+						}
+					}
+					unset($getid3_temp, $getid3_mp3);
+					break;
+
+				case 0xBC: // Program Stream Map
+				case 0xBD: // Private stream 1 (non MPEG audio, subpictures)
+				case 0xBE: // Padding stream
+				case 0xBF: // Private stream 2 (navigation data)
+				case 0xF0: // ECM stream
+				case 0xF1: // EMM stream
+				case 0xF2: // DSM-CC stream
+				case 0xF3: // ISO/IEC_13522_stream
+				case 0xF4: // ITU-I Rec. H.222.1 type A
+				case 0xF5: // ITU-I Rec. H.222.1 type B
+				case 0xF6: // ITU-I Rec. H.222.1 type C
+				case 0xF7: // ITU-I Rec. H.222.1 type D
+				case 0xF8: // ITU-I Rec. H.222.1 type E
+				case 0xF9: // ancilliary stream
+				case 0xFA: // ISO/IEC 14496-1 SL-packtized stream
+				case 0xFB: // ISO/IEC 14496-1 FlexMux stream
+				case 0xFC: // metadata stream
+				case 0xFD: // extended stream ID
+				case 0xFE: // reserved data stream
+				case 0xFF: // program stream directory
+					// ignore
+					break;
+
+				default:
+					// ignore
+					break;
+			}
+		} while (true);
+
+
+
+//		// Temporary hack to account for interleaving overhead:
+//		if (!empty($info['video']['bitrate']) && !empty($info['audio']['bitrate'])) {
+//			$info['playtime_seconds'] = (($info['avdataend'] - $info['avdataoffset']) * 8) / ($info['video']['bitrate'] + $info['audio']['bitrate']);
+//
+//			// Interleaved MPEG audio/video files have a certain amount of overhead that varies
+//			// by both video and audio bitrates, and not in any sensible, linear/logarithmic pattern
+//			// Use interpolated lookup tables to approximately guess how much is overhead, because
+//			// playtime is calculated as filesize / total-bitrate
+//			$info['playtime_seconds'] *= self::systemNonOverheadPercentage($info['video']['bitrate'], $info['audio']['bitrate']);
+//
+//			//switch ($info['video']['bitrate']) {
+//			//	case('5000000'):
+//			//		$multiplier = 0.93292642112380355828048824319889;
+//			//		break;
+//			//	case('5500000'):
+//			//		$multiplier = 0.93582895375200989965359777343219;
+//			//		break;
+//			//	case('6000000'):
+//			//		$multiplier = 0.93796247714820932532911373859139;
+//			//		break;
+//			//	case('7000000'):
+//			//		$multiplier = 0.9413264083635103463010117778776;
+//			//		break;
+//			//	default:
+//			//		$multiplier = 1;
+//			//		break;
+//			//}
+//			//$info['playtime_seconds'] *= $multiplier;
+//			//$this->warning('Interleaved MPEG audio/video playtime may be inaccurate. With current hack should be within a few seconds of accurate. Report to info@getid3.org if off by more than 10 seconds.');
+//			if ($info['video']['bitrate'] < 50000) {
+//				$this->warning('Interleaved MPEG audio/video playtime may be slightly inaccurate for video bitrates below 100kbps. Except in extreme low-bitrate situations, error should be less than 1%. Report to info@getid3.org if greater than this.');
+//			}
+//		}
+//
+/*
+$time_prev = 0;
+$byte_prev = 0;
+$vbr_bitrates = array();
+foreach ($info['mpeg']['group_of_pictures'] as $gopkey => $gopdata) {
+	$time_this = ($gopdata['time_code_hours'] * 3600) + ($gopdata['time_code_minutes'] * 60) + $gopdata['time_code_seconds'] + ($gopdata['time_code_seconds'] / 30);
+	$byte_this = $gopdata['byte_offset'];
+	if ($gopkey > 0) {
+		if ($time_this > $time_prev) {
+			$bytedelta = $byte_this - $byte_prev;
+			$timedelta = $time_this - $time_prev;
+			$this_bitrate = ($bytedelta * 8) / $timedelta;
+echo $gopkey.': ('.number_format($time_prev, 2).'-'.number_format($time_this, 2).') '.number_format($bytedelta).' bytes over '.number_format($timedelta, 3).' seconds = '.number_format($this_bitrate / 1000, 2).'kbps<br>';
+			$time_prev = $time_this;
+			$byte_prev = $byte_this;
+			$vbr_bitrates[] = $this_bitrate;
+		}
+	}
+}
+echo 'average_File_bitrate = '.number_format(array_sum($vbr_bitrates) / count($vbr_bitrates), 1).'<br>';
+*/
+//echo '<pre>'.print_r($FramesByGOP, true).'</pre>';
+		if (!empty($info['mpeg']['video']['bitrate_mode']) && ($info['mpeg']['video']['bitrate_mode'] == 'vbr')) {
+			$last_GOP_id = max(array_keys($FramesByGOP));
+			$frames_in_last_GOP = count($FramesByGOP[$last_GOP_id]);
+			$gopdata = &$info['mpeg']['group_of_pictures'][$last_GOP_id];
+			$info['playtime_seconds'] = ($gopdata['time_code_hours'] * 3600) + ($gopdata['time_code_minutes'] * 60) + $gopdata['time_code_seconds'] + (($gopdata['time_code_pictures'] + $frames_in_last_GOP + 1) / $info['mpeg']['video']['frame_rate']);
+			if (!isset($info['video']['bitrate'])) {
+				$overall_bitrate = ($info['avdataend'] - $info['avdataoffset']) * 8 / $info['playtime_seconds'];
+				$info['video']['bitrate'] = $overall_bitrate - (isset($info['audio']['bitrate']) ? $info['audio']['bitrate'] : 0);
+			}
+			unset($info['mpeg']['group_of_pictures']);
+		}
+
+		return true;
+	}
+
+	/**
+	 * @param string $bitstream
+	 * @param int    $bitstreamoffset
+	 * @param int    $bits_to_read
+	 * @param bool $return_singlebit_as_boolean
+	 *
+	 * @return bool|int
+	 */
+	private function readBitsFromStream(&$bitstream, &$bitstreamoffset, $bits_to_read, $return_singlebit_as_boolean=true) {
+		$return = bindec(substr($bitstream, $bitstreamoffset, $bits_to_read));
+		$bitstreamoffset += $bits_to_read;
+		if (($bits_to_read == 1) && $return_singlebit_as_boolean) {
+			$return = (bool) $return;
+		}
+		return $return;
+	}
+
+	/**
+	 * @param int $VideoBitrate
+	 * @param int $AudioBitrate
+	 *
+	 * @return float|int
+	 */
+	public static function systemNonOverheadPercentage($VideoBitrate, $AudioBitrate) {
+		$OverheadPercentage = 0;
+
+		$AudioBitrate = max(min($AudioBitrate / 1000,   384), 32); // limit to range of 32kbps - 384kbps (should be only legal bitrates, but maybe VBR?)
+		$VideoBitrate = max(min($VideoBitrate / 1000, 10000), 10); // limit to range of 10kbps -  10Mbps (beyond that curves flatten anyways, no big loss)
+
+
+		//OMBB[audiobitrate]              = array(video-10kbps,       video-100kbps,      video-1000kbps,     video-10000kbps)
+		$OverheadMultiplierByBitrate[32]  = array(0, 0.9676287944368530, 0.9802276264360310, 0.9844916183244460, 0.9852821845179940);
+		$OverheadMultiplierByBitrate[48]  = array(0, 0.9779100089209830, 0.9787770035359320, 0.9846738664076130, 0.9852683013799960);
+		$OverheadMultiplierByBitrate[56]  = array(0, 0.9731249855367600, 0.9776624308938040, 0.9832606361852130, 0.9843922606633340);
+		$OverheadMultiplierByBitrate[64]  = array(0, 0.9755642683275760, 0.9795256705493390, 0.9836573009193170, 0.9851122539404470);
+		$OverheadMultiplierByBitrate[96]  = array(0, 0.9788025247497290, 0.9798553314148700, 0.9822956869792560, 0.9834815119124690);
+		$OverheadMultiplierByBitrate[128] = array(0, 0.9816940050925480, 0.9821675936072120, 0.9829756927470870, 0.9839763420152050);
+		$OverheadMultiplierByBitrate[160] = array(0, 0.9825894094561180, 0.9820913399073960, 0.9823907143253970, 0.9832821783651570);
+		$OverheadMultiplierByBitrate[192] = array(0, 0.9832038474336260, 0.9825731694317960, 0.9821028622712400, 0.9828262076447620);
+		$OverheadMultiplierByBitrate[224] = array(0, 0.9836516298538770, 0.9824718601823890, 0.9818302180625380, 0.9823735101626480);
+		$OverheadMultiplierByBitrate[256] = array(0, 0.9845863022094920, 0.9837229411967540, 0.9824521662210830, 0.9828645172100790);
+		$OverheadMultiplierByBitrate[320] = array(0, 0.9849565280263180, 0.9837683142805110, 0.9822885275960400, 0.9824424382727190);
+		$OverheadMultiplierByBitrate[384] = array(0, 0.9856094774357600, 0.9844573394432720, 0.9825970399837330, 0.9824673808303890);
+
+		$BitrateToUseMin = 32;
+		$BitrateToUseMax = 32;
+		$previousBitrate = 32;
+		foreach ($OverheadMultiplierByBitrate as $key => $value) {
+			if ($AudioBitrate >= $previousBitrate) {
+				$BitrateToUseMin = $previousBitrate;
+			}
+			if ($AudioBitrate < $key) {
+				$BitrateToUseMax = $key;
+				break;
+			}
+			$previousBitrate = $key;
+		}
+		$FactorA = ($BitrateToUseMax - $AudioBitrate) / ($BitrateToUseMax - $BitrateToUseMin);
+
+		$VideoBitrateLog10 = log10($VideoBitrate);
+		$VideoFactorMin1 = $OverheadMultiplierByBitrate[$BitrateToUseMin][floor($VideoBitrateLog10)];
+		$VideoFactorMin2 = $OverheadMultiplierByBitrate[$BitrateToUseMax][floor($VideoBitrateLog10)];
+		$VideoFactorMax1 = $OverheadMultiplierByBitrate[$BitrateToUseMin][ceil($VideoBitrateLog10)];
+		$VideoFactorMax2 = $OverheadMultiplierByBitrate[$BitrateToUseMax][ceil($VideoBitrateLog10)];
+		$FactorV = $VideoBitrateLog10 - floor($VideoBitrateLog10);
+
+		$OverheadPercentage  = $VideoFactorMin1 *      $FactorA  *      $FactorV;
+		$OverheadPercentage += $VideoFactorMin2 * (1 - $FactorA) *      $FactorV;
+		$OverheadPercentage += $VideoFactorMax1 *      $FactorA  * (1 - $FactorV);
+		$OverheadPercentage += $VideoFactorMax2 * (1 - $FactorA) * (1 - $FactorV);
+
+		return $OverheadPercentage;
+	}
+
+	/**
+	 * @param int $rawframerate
+	 *
+	 * @return float
+	 */
+	public static function videoFramerateLookup($rawframerate) {
+		$lookup = array(0, 23.976, 24, 25, 29.97, 30, 50, 59.94, 60);
+		return (float) (isset($lookup[$rawframerate]) ? $lookup[$rawframerate] : 0);
+	}
+
+	/**
+	 * @param int $rawaspectratio
+	 * @param int $mpeg_version
+	 * @param int $width
+	 * @param int $height
+	 *
+	 * @return float
+	 */
+	public static function videoAspectRatioLookup($rawaspectratio, $mpeg_version=1, $width=0, $height=0) {
+		$lookup = array(
+			1 => array(0, 1, 0.6735, 0.7031, 0.7615, 0.8055, 0.8437, 0.8935, 0.9157, 0.9815, 1.0255, 1.0695, 1.0950, 1.1575, 1.2015, 0),
+			2 => array(0, 1, 1.3333, 1.7778, 2.2100, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+		);
+		$ratio = (float) (isset($lookup[$mpeg_version][$rawaspectratio]) ? $lookup[$mpeg_version][$rawaspectratio] : 0);
+		if ($mpeg_version == 2 && $ratio != 1) {
+			// Calculate pixel aspect ratio from MPEG-2 display aspect ratio
+			$ratio = $ratio * $height / $width;
+		}
+		return $ratio;
+	}
+
+	/**
+	 * @param int $rawaspectratio
+	 * @param int $mpeg_version
+	 *
+	 * @return string
+	 */
+	public static function videoAspectRatioTextLookup($rawaspectratio, $mpeg_version=1) {
+		$lookup = array(
+			1 => array('forbidden', 'square pixels', '0.6735', '16:9, 625 line, PAL', '0.7615', '0.8055', '16:9, 525 line, NTSC', '0.8935', '4:3, 625 line, PAL, CCIR601', '0.9815', '1.0255', '1.0695', '4:3, 525 line, NTSC, CCIR601', '1.1575', '1.2015', 'reserved'),
+			2 => array('forbidden', 'square pixels', '4:3', '16:9', '2.21:1', 'reserved', 'reserved', 'reserved', 'reserved', 'reserved', 'reserved', 'reserved', 'reserved', 'reserved', 'reserved', 'reserved'), // http://dvd.sourceforge.net/dvdinfo/mpeghdrs.html
+		);
+		return (isset($lookup[$mpeg_version][$rawaspectratio]) ? $lookup[$mpeg_version][$rawaspectratio] : '');
+	}
+
+	/**
+	 * @param int $video_format
+	 *
+	 * @return string
+	 */
+	public static function videoFormatTextLookup($video_format) {
+		// ISO/IEC 13818-2, section 6.3.6, Table 6-6. Meaning of video_format
+		$lookup = array('component', 'PAL', 'NTSC', 'SECAM', 'MAC', 'Unspecified video format', 'reserved(6)', 'reserved(7)');
+		return (isset($lookup[$video_format]) ? $lookup[$video_format] : '');
+	}
+
+	/**
+	 * @param int $scalable_mode
+	 *
+	 * @return string
+	 */
+	public static function scalableModeTextLookup($scalable_mode) {
+		// ISO/IEC 13818-2, section 6.3.8, Table 6-10. Definition of scalable_mode
+		$lookup = array('data partitioning', 'spatial scalability', 'SNR scalability', 'temporal scalability');
+		return (isset($lookup[$scalable_mode]) ? $lookup[$scalable_mode] : '');
+	}
+
+	/**
+	 * @param int $picture_structure
+	 *
+	 * @return string
+	 */
+	public static function pictureStructureTextLookup($picture_structure) {
+		// ISO/IEC 13818-2, section 6.3.11, Table 6-14 Meaning of picture_structure
+		$lookup = array('reserved', 'Top Field', 'Bottom Field', 'Frame picture');
+		return (isset($lookup[$picture_structure]) ? $lookup[$picture_structure] : '');
+	}
+
+	/**
+	 * @param int $chroma_format
+	 *
+	 * @return string
+	 */
+	public static function chromaFormatTextLookup($chroma_format) {
+		// ISO/IEC 13818-2, section 6.3.11, Table 6-14 Meaning of picture_structure
+		$lookup = array('reserved', '4:2:0', '4:2:2', '4:4:4');
+		return (isset($lookup[$chroma_format]) ? $lookup[$chroma_format] : '');
+	}
+
+}