//
// 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).'
';
if ($MPEGstreamDataOffset > (strlen($MPEGstreamData) - 16384)) {
// buffer running low, get more data
//echo 'reading more data
';
$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.
';
break;
} else {
$MPEGstreamDataOffset = $StartCodeOffset;
$prevStartCodeValue = $StartCodeValue;
$StartCodeValue = ord(substr($MPEGstreamData, $StartCodeOffset + 3, 1));
//echo 'Found "'.strtoupper(dechex($StartCodeValue)).'" at offset '.($MPEGstreamBaseOffset + $StartCodeOffset).' ($MPEGstreamDataOffset = '.$MPEGstreamDataOffset.')
';
}
$MPEGstreamDataOffset += 4;
switch ($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 $info['mpeg']['video']['raw']['extension_start_code_identifier'].'
';
switch ($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'].'
';
$PackedElementaryStream['scrambling_control'] = self::readBitsFromStream($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 + $i).'
';
if ($getid3_mp3->decodeMPEGaudioHeader($MPEGstreamBaseOffset + $StartCodeOffset + 4 + 8 + $i, $getid3_temp->info, false)) {
//echo 'yes!
';
$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
';
$time_prev = $time_this;
$byte_prev = $byte_this;
$vbr_bitrates[] = $this_bitrate;
}
}
}
echo 'average_File_bitrate = '.number_format(array_sum($vbr_bitrates) / count($vbr_bitrates), 1).'
';
*/
//echo ''.print_r($FramesByGOP, true).'
';
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] : '');
}
}