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authorTheTroll <trolldev@gmail.com>2010-02-25 15:51:44 +0100
committerTheTroll <trolldev@gmail.com>2010-02-25 15:51:44 +0100
commit45ee8db7fd22ff9c9fe200802ed4e179000a5bb4 (patch)
tree228425717006ca104f9b1dc46e4b38d53ea6f7cc /getid3/module.audio-video.mpeg.php
parent1d3095213541ba77015742a4c05cfcf66fd9c7e7 (diff)
downloadistreamdev-45ee8db7fd22ff9c9fe200802ed4e179000a5bb4.tar.gz
istreamdev-45ee8db7fd22ff9c9fe200802ed4e179000a5bb4.tar.bz2
Replaced mediainfo calls by getid3
Diffstat (limited to 'getid3/module.audio-video.mpeg.php')
-rw-r--r--getid3/module.audio-video.mpeg.php292
1 files changed, 292 insertions, 0 deletions
diff --git a/getid3/module.audio-video.mpeg.php b/getid3/module.audio-video.mpeg.php
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+<?php
+/////////////////////////////////////////////////////////////////
+/// getID3() by James Heinrich <info@getid3.org> //
+// available at http://getid3.sourceforge.net //
+// or http://www.getid3.org //
+/////////////////////////////////////////////////////////////////
+// See readme.txt for more details //
+/////////////////////////////////////////////////////////////////
+// //
+// module.audio-video.mpeg.php //
+// module for analyzing MPEG files //
+// dependencies: module.audio.mp3.php //
+// ///
+/////////////////////////////////////////////////////////////////
+
+getid3_lib::IncludeDependency(GETID3_INCLUDEPATH.'module.audio.mp3.php', __FILE__, true);
+
+define('GETID3_MPEG_VIDEO_PICTURE_START', "\x00\x00\x01\x00");
+define('GETID3_MPEG_VIDEO_USER_DATA_START', "\x00\x00\x01\xB2");
+define('GETID3_MPEG_VIDEO_SEQUENCE_HEADER', "\x00\x00\x01\xB3");
+define('GETID3_MPEG_VIDEO_SEQUENCE_ERROR', "\x00\x00\x01\xB4");
+define('GETID3_MPEG_VIDEO_EXTENSION_START', "\x00\x00\x01\xB5");
+define('GETID3_MPEG_VIDEO_SEQUENCE_END', "\x00\x00\x01\xB7");
+define('GETID3_MPEG_VIDEO_GROUP_START', "\x00\x00\x01\xB8");
+define('GETID3_MPEG_AUDIO_START', "\x00\x00\x01\xC0");
+
+
+class getid3_mpeg
+{
+
+ function getid3_mpeg(&$fd, &$ThisFileInfo) {
+ if ($ThisFileInfo['avdataend'] <= $ThisFileInfo['avdataoffset']) {
+ $ThisFileInfo['error'][] = '"avdataend" ('.$ThisFileInfo['avdataend'].') is unexpectedly less-than-or-equal-to "avdataoffset" ('.$ThisFileInfo['avdataoffset'].')';
+ return false;
+ }
+ $ThisFileInfo['fileformat'] = 'mpeg';
+ fseek($fd, $ThisFileInfo['avdataoffset'], SEEK_SET);
+ $MPEGstreamData = fread($fd, min(100000, $ThisFileInfo['avdataend'] - $ThisFileInfo['avdataoffset']));
+ $MPEGstreamDataLength = strlen($MPEGstreamData);
+
+ $foundVideo = true;
+ $VideoChunkOffset = 0;
+ while (substr($MPEGstreamData, $VideoChunkOffset++, 4) !== GETID3_MPEG_VIDEO_SEQUENCE_HEADER) {
+ if ($VideoChunkOffset >= $MPEGstreamDataLength) {
+ $foundVideo = false;
+ break;
+ }
+ }
+ if ($foundVideo) {
+
+ // Start code 32 bits
+ // horizontal frame size 12 bits
+ // vertical frame size 12 bits
+ // pixel aspect ratio 4 bits
+ // frame rate 4 bits
+ // bitrate 18 bits
+ // marker bit 1 bit
+ // VBV buffer size 10 bits
+ // constrained parameter flag 1 bit
+ // intra quant. matrix flag 1 bit
+ // intra quant. matrix values 512 bits (present if matrix flag == 1)
+ // non-intra quant. matrix flag 1 bit
+ // non-intra quant. matrix values 512 bits (present if matrix flag == 1)
+
+ $ThisFileInfo['video']['dataformat'] = 'mpeg';
+
+ $VideoChunkOffset += (strlen(GETID3_MPEG_VIDEO_SEQUENCE_HEADER) - 1);
+
+ $FrameSizeDWORD = getid3_lib::BigEndian2Int(substr($MPEGstreamData, $VideoChunkOffset, 3));
+ $VideoChunkOffset += 3;
+
+ $AspectRatioFrameRateDWORD = getid3_lib::BigEndian2Int(substr($MPEGstreamData, $VideoChunkOffset, 1));
+ $VideoChunkOffset += 1;
+
+ $assortedinformation = getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $VideoChunkOffset, 4));
+ $VideoChunkOffset += 4;
+
+ $ThisFileInfo['mpeg']['video']['raw']['framesize_horizontal'] = ($FrameSizeDWORD & 0xFFF000) >> 12; // 12 bits for horizontal frame size
+ $ThisFileInfo['mpeg']['video']['raw']['framesize_vertical'] = ($FrameSizeDWORD & 0x000FFF); // 12 bits for vertical frame size
+ $ThisFileInfo['mpeg']['video']['raw']['pixel_aspect_ratio'] = ($AspectRatioFrameRateDWORD & 0xF0) >> 4;
+ $ThisFileInfo['mpeg']['video']['raw']['frame_rate'] = ($AspectRatioFrameRateDWORD & 0x0F);
+
+ $ThisFileInfo['mpeg']['video']['framesize_horizontal'] = $ThisFileInfo['mpeg']['video']['raw']['framesize_horizontal'];
+ $ThisFileInfo['mpeg']['video']['framesize_vertical'] = $ThisFileInfo['mpeg']['video']['raw']['framesize_vertical'];
+
+ $ThisFileInfo['mpeg']['video']['pixel_aspect_ratio'] = $this->MPEGvideoAspectRatioLookup($ThisFileInfo['mpeg']['video']['raw']['pixel_aspect_ratio']);
+ $ThisFileInfo['mpeg']['video']['pixel_aspect_ratio_text'] = $this->MPEGvideoAspectRatioTextLookup($ThisFileInfo['mpeg']['video']['raw']['pixel_aspect_ratio']);
+ $ThisFileInfo['mpeg']['video']['frame_rate'] = $this->MPEGvideoFramerateLookup($ThisFileInfo['mpeg']['video']['raw']['frame_rate']);
+
+ $ThisFileInfo['mpeg']['video']['raw']['bitrate'] = getid3_lib::Bin2Dec(substr($assortedinformation, 0, 18));
+ $ThisFileInfo['mpeg']['video']['raw']['marker_bit'] = (bool) getid3_lib::Bin2Dec(substr($assortedinformation, 18, 1));
+ $ThisFileInfo['mpeg']['video']['raw']['vbv_buffer_size'] = getid3_lib::Bin2Dec(substr($assortedinformation, 19, 10));
+ $ThisFileInfo['mpeg']['video']['raw']['constrained_param_flag'] = (bool) getid3_lib::Bin2Dec(substr($assortedinformation, 29, 1));
+ $ThisFileInfo['mpeg']['video']['raw']['intra_quant_flag'] = (bool) getid3_lib::Bin2Dec(substr($assortedinformation, 30, 1));
+ if ($ThisFileInfo['mpeg']['video']['raw']['intra_quant_flag']) {
+
+ // read 512 bits
+ $ThisFileInfo['mpeg']['video']['raw']['intra_quant'] = getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $VideoChunkOffset, 64));
+ $VideoChunkOffset += 64;
+
+ $ThisFileInfo['mpeg']['video']['raw']['non_intra_quant_flag'] = (bool) getid3_lib::Bin2Dec(substr($ThisFileInfo['mpeg']['video']['raw']['intra_quant'], 511, 1));
+ $ThisFileInfo['mpeg']['video']['raw']['intra_quant'] = getid3_lib::Bin2Dec(substr($assortedinformation, 31, 1)).substr(getid3_lib::BigEndian2Bin(substr($MPEGstreamData, $VideoChunkOffset, 64)), 0, 511);
+
+ if ($ThisFileInfo['mpeg']['video']['raw']['non_intra_quant_flag']) {
+ $ThisFileInfo['mpeg']['video']['raw']['non_intra_quant'] = substr($MPEGstreamData, $VideoChunkOffset, 64);
+ $VideoChunkOffset += 64;
+ }
+
+ } else {
+
+ $ThisFileInfo['mpeg']['video']['raw']['non_intra_quant_flag'] = (bool) getid3_lib::Bin2Dec(substr($assortedinformation, 31, 1));
+ if ($ThisFileInfo['mpeg']['video']['raw']['non_intra_quant_flag']) {
+ $ThisFileInfo['mpeg']['video']['raw']['non_intra_quant'] = substr($MPEGstreamData, $VideoChunkOffset, 64);
+ $VideoChunkOffset += 64;
+ }
+
+ }
+
+ if ($ThisFileInfo['mpeg']['video']['raw']['bitrate'] == 0x3FFFF) { // 18 set bits
+
+ $ThisFileInfo['warning'][] = 'This version of getID3() ['.GETID3_VERSION.'] cannot determine average bitrate of VBR MPEG video files';
+ $ThisFileInfo['mpeg']['video']['bitrate_mode'] = 'vbr';
+
+ } else {
+
+ $ThisFileInfo['mpeg']['video']['bitrate'] = $ThisFileInfo['mpeg']['video']['raw']['bitrate'] * 400;
+ $ThisFileInfo['mpeg']['video']['bitrate_mode'] = 'cbr';
+ $ThisFileInfo['video']['bitrate'] = $ThisFileInfo['mpeg']['video']['bitrate'];
+
+ }
+
+ $ThisFileInfo['video']['resolution_x'] = $ThisFileInfo['mpeg']['video']['framesize_horizontal'];
+ $ThisFileInfo['video']['resolution_y'] = $ThisFileInfo['mpeg']['video']['framesize_vertical'];
+ $ThisFileInfo['video']['frame_rate'] = $ThisFileInfo['mpeg']['video']['frame_rate'];
+ $ThisFileInfo['video']['bitrate_mode'] = $ThisFileInfo['mpeg']['video']['bitrate_mode'];
+ $ThisFileInfo['video']['pixel_aspect_ratio'] = $ThisFileInfo['mpeg']['video']['pixel_aspect_ratio'];
+ $ThisFileInfo['video']['lossless'] = false;
+ $ThisFileInfo['video']['bits_per_sample'] = 24;
+
+ } else {
+
+ $ThisFileInfo['error'][] = 'Could not find start of video block in the first 100,000 bytes (or before end of file) - this might not be an MPEG-video file?';
+
+ }
+
+ //0x000001B3 begins the sequence_header of every MPEG video stream.
+ //But in MPEG-2, this header must immediately be followed by an
+ //extension_start_code (0x000001B5) with a sequence_extension ID (1).
+ //(This extension contains all the additional MPEG-2 stuff.)
+ //MPEG-1 doesn't have this extension, so that's a sure way to tell the
+ //difference between MPEG-1 and MPEG-2 video streams.
+
+ if (substr($MPEGstreamData, $VideoChunkOffset, 4) == GETID3_MPEG_VIDEO_EXTENSION_START) {
+ $ThisFileInfo['video']['codec'] = 'MPEG-2';
+ } else {
+ $ThisFileInfo['video']['codec'] = 'MPEG-1';
+ }
+
+
+ $AudioChunkOffset = 0;
+ while (true) {
+ while (substr($MPEGstreamData, $AudioChunkOffset++, 4) !== GETID3_MPEG_AUDIO_START) {
+ if ($AudioChunkOffset >= $MPEGstreamDataLength) {
+ break 2;
+ }
+ }
+
+ for ($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
+
+ $dummy = $ThisFileInfo;
+ if (getid3_mp3::decodeMPEGaudioHeader($fd, ($AudioChunkOffset + 3) + 8 + $i, $dummy, false)) {
+ $ThisFileInfo = $dummy;
+ $ThisFileInfo['audio']['bitrate_mode'] = 'cbr';
+ $ThisFileInfo['audio']['lossless'] = false;
+ break 2;
+
+ }
+ }
+ }
+
+ // Temporary hack to account for interleaving overhead:
+ if (!empty($ThisFileInfo['video']['bitrate']) && !empty($ThisFileInfo['audio']['bitrate'])) {
+ $ThisFileInfo['playtime_seconds'] = (($ThisFileInfo['avdataend'] - $ThisFileInfo['avdataoffset']) * 8) / ($ThisFileInfo['video']['bitrate'] + $ThisFileInfo['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 patter
+ // Use interpolated lookup tables to approximately guess how much is overhead, because
+ // playtime is calculated as filesize / total-bitrate
+ $ThisFileInfo['playtime_seconds'] *= $this->MPEGsystemNonOverheadPercentage($ThisFileInfo['video']['bitrate'], $ThisFileInfo['audio']['bitrate']);
+
+ //switch ($ThisFileInfo['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:
+ // $multiplier = 1;
+ // break;
+ //}
+ //$ThisFileInfo['playtime_seconds'] *= $multiplier;
+ //$ThisFileInfo['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 ($ThisFileInfo['video']['bitrate'] < 50000) {
+ $ThisFileInfo['warning'][] = 'Interleaved MPEG audio/video playtime may be slightly inaccurate for video bitrates below 100kbps. Except in extreme low-bitrate situations, error should be less than 1%. Report to info@getid3.org if greater than this.';
+ }
+ }
+
+ return true;
+ }
+
+
+ function MPEGsystemNonOverheadPercentage($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 $OverheadPercentage;
+ }
+
+
+ function MPEGvideoFramerateLookup($rawframerate) {
+ $MPEGvideoFramerateLookup = array(0, 23.976, 24, 25, 29.97, 30, 50, 59.94, 60);
+ return (isset($MPEGvideoFramerateLookup[$rawframerate]) ? (float) $MPEGvideoFramerateLookup[$rawframerate] : (float) 0);
+ }
+
+ function MPEGvideoAspectRatioLookup($rawaspectratio) {
+ $MPEGvideoAspectRatioLookup = array(0, 1, 0.6735, 0.7031, 0.7615, 0.8055, 0.8437, 0.8935, 0.9157, 0.9815, 1.0255, 1.0695, 1.0950, 1.1575, 1.2015, 0);
+ return (isset($MPEGvideoAspectRatioLookup[$rawaspectratio]) ? (float) $MPEGvideoAspectRatioLookup[$rawaspectratio] : (float) 0);
+ }
+
+ function MPEGvideoAspectRatioTextLookup($rawaspectratio) {
+ $MPEGvideoAspectRatioTextLookup = array('forbidden', 'square pixels', '0.6735', '16:9, 625 line, PAL', '0.7615', '0.8055', '16:9, 525 line, NTSC', '0.8935', '4:3, 625 line, PAL, CCIR601', '0.9815', '1.0255', '1.0695', '4:3, 525 line, NTSC, CCIR601', '1.1575', '1.2015', 'reserved');
+ return (isset($MPEGvideoAspectRatioTextLookup[$rawaspectratio]) ? $MPEGvideoAspectRatioTextLookup[$rawaspectratio] : '');
+ }
+
+}
+
+
+?> \ No newline at end of file