#------------------------------------------------------------------------------ # File: M2TS.pm # # Description: Read M2TS (AVCHD) meta information # # Revisions: 2009/07/03 - P. Harvey Created # # References: 1) http://neuron2.net/library/mpeg2/iso13818-1.pdf # 2) http://www.blu-raydisc.com/Assets/Downloadablefile/BD-RE_Part3_V2.1_WhitePaper_080406-15271.pdf # 3) http://www.videohelp.com/forum/archive/reading-avchd-playlist-files-bdmv-playlist-mpl-t358888.html # 4) http://en.wikipedia.org/wiki/MPEG_transport_stream # 5) http://www.dunod.com/documents/9782100493463/49346_DVB.pdf # 6) http://trac.handbrake.fr/browser/trunk/libhb/stream.c # 7) http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=04560141 # 8) http://www.w6rz.net/xport.zip # 9) https://en.wikipedia.org/wiki/Program-specific_information # # Notes: Variable names containing underlines are the same as in ref 1. # # Glossary: PES = Packetized Elementary Stream # PAT = Program Association Table # PMT = Program Map Table # PCR = Program Clock Reference # PID = Packet Identifier # # To Do: - parse PCR to obtain average bitrates? #------------------------------------------------------------------------------ package Image::ExifTool::M2TS; use strict; use vars qw($VERSION); use Image::ExifTool qw(:DataAccess :Utils); $VERSION = '1.23'; # program map table "stream_type" lookup (ref 6/1/9) my %streamType = ( 0x00 => 'Reserved', 0x01 => 'MPEG-1 Video', 0x02 => 'MPEG-2 Video', 0x03 => 'MPEG-1 Audio', 0x04 => 'MPEG-2 Audio', 0x05 => 'ISO 13818-1 private sections', 0x06 => 'ISO 13818-1 PES private data', 0x07 => 'ISO 13522 MHEG', 0x08 => 'ISO 13818-1 DSM-CC', 0x09 => 'ISO 13818-1 auxiliary', 0x0A => 'ISO 13818-6 multi-protocol encap', 0x0B => 'ISO 13818-6 DSM-CC U-N msgs', 0x0C => 'ISO 13818-6 stream descriptors', 0x0D => 'ISO 13818-6 sections', 0x0E => 'ISO 13818-1 auxiliary', 0x0F => 'MPEG-2 AAC Audio', 0x10 => 'MPEG-4 Video', 0x11 => 'MPEG-4 LATM AAC Audio', 0x12 => 'MPEG-4 generic', 0x13 => 'ISO 14496-1 SL-packetized', 0x14 => 'ISO 13818-6 Synchronized Download Protocol', 0x15 => 'Packetized metadata', 0x16 => 'Sectioned metadata', 0x17 => 'ISO/IEC 13818-6 DSM CC Data Carousel metadata', 0x18 => 'ISO/IEC 13818-6 DSM CC Object Carousel metadata', 0x19 => 'ISO/IEC 13818-6 Synchronized Download Protocol metadata', 0x1a => 'ISO/IEC 13818-11 IPMP', 0x1b => 'H.264 (AVC) Video', 0x1c => 'ISO/IEC 14496-3 (MPEG-4 raw audio)', 0x1d => 'ISO/IEC 14496-17 (MPEG-4 text)', 0x1e => 'ISO/IEC 23002-3 (MPEG-4 auxiliary video)', 0x1f => 'ISO/IEC 14496-10 SVC (MPEG-4 AVC sub-bitstream)', 0x20 => 'ISO/IEC 14496-10 MVC (MPEG-4 AVC sub-bitstream)', 0x21 => 'ITU-T Rec. T.800 and ISO/IEC 15444 (JPEG 2000 video)', 0x24 => 'H.265 (HEVC) Video', #PH 0x42 => 'Chinese Video Standard', 0x7f => 'ISO/IEC 13818-11 IPMP (DRM)', 0x80 => 'DigiCipher II Video', 0x81 => 'A52/AC-3 Audio', 0x82 => 'HDMV DTS Audio', 0x83 => 'LPCM Audio', 0x84 => 'SDDS Audio', 0x85 => 'ATSC Program ID', 0x86 => 'DTS-HD Audio', 0x87 => 'E-AC-3 Audio', 0x8a => 'DTS Audio', 0x90 => 'PGS Audio', #https://www.avsforum.com/threads/bass-eq-for-filtered-movies.2995212/page-399 0x91 => 'A52b/AC-3 Audio', 0x92 => 'DVD_SPU vls Subtitle', 0x94 => 'SDDS Audio', 0xa0 => 'MSCODEC Video', 0xea => 'Private ES (VC-1)', # 0x80-0xFF => 'User Private', ); # "table_id" values (ref 5) my %tableID = ( 0x00 => 'Program Association', 0x01 => 'Conditional Access', 0x02 => 'Program Map', 0x03 => 'Transport Stream Description', 0x40 => 'Actual Network Information', 0x41 => 'Other Network Information', 0x42 => 'Actual Service Description', 0x46 => 'Other Service Description', 0x4a => 'Bouquet Association', 0x4e => 'Actual Event Information - Present/Following', 0x4f => 'Other Event Information - Present/Following', 0x50 => 'Actual Event Information - Schedule', #(also 0x51-0x5f) 0x60 => 'Other Event Information - Schedule', # (also 0x61-0x6f) 0x70 => 'Time/Date', 0x71 => 'Running Status', 0x72 => 'Stuffing', 0x73 => 'Time Offset', 0x7e => 'Discontinuity Information', 0x7f => 'Selection Information', # 0x80-0xfe => 'User Defined', ); # PES stream ID's for which a syntax field does not exist my %noSyntax = ( 0xbc => 1, # program_stream_map 0xbe => 1, # padding_stream 0xbf => 1, # private_stream_2 0xf0 => 1, # ECM_stream 0xf1 => 1, # EMM_stream 0xf2 => 1, # DSMCC_stream 0xf8 => 1, # ITU-T Rec. H.222.1 type E stream 0xff => 1, # program_stream_directory ); my $knotsToKph = 1.852; # knots --> km/h # information extracted from the MPEG-2 transport stream %Image::ExifTool::M2TS::Main = ( GROUPS => { 2 => 'Video' }, VARS => { NO_ID => 1 }, NOTES => q{ The MPEG-2 transport stream is used as a container for many different audio/video formats (including AVCHD). This table lists information extracted from M2TS files. }, VideoStreamType => { PrintHex => 1, PrintConv => \%streamType, SeparateTable => 'StreamType', }, AudioStreamType => { PrintHex => 1, PrintConv => \%streamType, SeparateTable => 'StreamType', }, Duration => { Notes => q{ the -fast option may be used to avoid scanning to the end of file to calculate the Duration }, ValueConv => '$val / 27000000', # (clock is 27MHz) PrintConv => 'ConvertDuration($val)', }, # the following tags are for documentation purposes only _AC3 => { SubDirectory => { TagTable => 'Image::ExifTool::M2TS::AC3' } }, _H264 => { SubDirectory => { TagTable => 'Image::ExifTool::H264::Main' } }, _MISB => { SubDirectory => { TagTable => 'Image::ExifTool::MISB::Main' } }, ); # information extracted from AC-3 audio streams %Image::ExifTool::M2TS::AC3 = ( GROUPS => { 1 => 'AC3', 2 => 'Audio' }, VARS => { NO_ID => 1 }, NOTES => 'Tags extracted from AC-3 audio streams.', AudioSampleRate => { PrintConv => { 0 => '48000', 1 => '44100', 2 => '32000', }, }, AudioBitrate => { PrintConvColumns => 2, ValueConv => { 0 => 32000, 1 => 40000, 2 => 48000, 3 => 56000, 4 => 64000, 5 => 80000, 6 => 96000, 7 => 112000, 8 => 128000, 9 => 160000, 10 => 192000, 11 => 224000, 12 => 256000, 13 => 320000, 14 => 384000, 15 => 448000, 16 => 512000, 17 => 576000, 18 => 640000, 32 => '32000 max', 33 => '40000 max', 34 => '48000 max', 35 => '56000 max', 36 => '64000 max', 37 => '80000 max', 38 => '96000 max', 39 => '112000 max', 40 => '128000 max', 41 => '160000 max', 42 => '192000 max', 43 => '224000 max', 44 => '256000 max', 45 => '320000 max', 46 => '384000 max', 47 => '448000 max', 48 => '512000 max', 49 => '576000 max', 50 => '640000 max', }, PrintConv => 'ConvertBitrate($val)', }, SurroundMode => { PrintConv => { 0 => 'Not indicated', 1 => 'Not Dolby surround', 2 => 'Dolby surround', }, }, AudioChannels => { PrintConvColumns => 2, PrintConv => { 0 => '1 + 1', 1 => 1, 2 => 2, 3 => 3, 4 => '2/1', 5 => '3/1', 6 => '2/2', 7 => '3/2', 8 => 1, 9 => '2 max', 10 => '3 max', 11 => '4 max', 12 => '5 max', 13 => '6 max', }, }, ); #------------------------------------------------------------------------------ # Extract information from AC-3 audio stream # Inputs: 0) ExifTool ref, 1) data ref # Reference: http://www.atsc.org/standards/a_52b.pdf sub ParseAC3Audio($$) { my ($et, $dataPt) = @_; if ($$dataPt =~ /\x0b\x77..(.)/sg) { my $sampleRate = ord($1) >> 6; my $tagTablePtr = GetTagTable('Image::ExifTool::M2TS::AC3'); $et->HandleTag($tagTablePtr, AudioSampleRate => $sampleRate); } } #------------------------------------------------------------------------------ # Extract information from AC-3 stream descriptor # Inputs: 0) ExifTool ref, 1) data ref # Reference: http://www.atsc.org/standards/a_52b.pdf # Note: This information is duplicated in the Audio stream, but it # is somewhat easier to extract it from the descriptor instead sub ParseAC3Descriptor($$) { my ($et, $dataPt) = @_; return if length $$dataPt < 3; my @v = unpack('C3', $$dataPt); my $tagTablePtr = GetTagTable('Image::ExifTool::M2TS::AC3'); # $et->HandleTag($tagTablePtr, 'AudioSampleRate', $v[0] >> 5); $et->HandleTag($tagTablePtr, 'AudioBitrate', $v[1] >> 2); $et->HandleTag($tagTablePtr, 'SurroundMode', $v[1] & 0x03); $et->HandleTag($tagTablePtr, 'AudioChannels', ($v[2] >> 1) & 0x0f); # don't (yet) decode any more (language codes, etc) } #------------------------------------------------------------------------------ # Parse PID stream data # Inputs: 0) ExifTool ref, 1) PID number, 2) PID type, 3) PID name, 4) data ref # Returns: 0=stream parsed OK, # 1=stream parsed but we want to parse more of these, # -1=can't parse yet because we don't know the type sub ParsePID($$$$$) { my ($et, $pid, $type, $pidName, $dataPt) = @_; # can't parse until we know the type (Program Map Table may be later in the stream) return -1 unless defined $type; my $verbose = $et->Options('Verbose'); if ($verbose > 1) { my $out = $et->Options('TextOut'); printf $out "Parsing stream 0x%.4x (%s) %d bytes\n", $pid, $pidName, length($$dataPt); $et->VerboseDump($dataPt); } my $more = 0; if ($type == 0x01 or $type == 0x02) { # MPEG-1/MPEG-2 Video require Image::ExifTool::MPEG; Image::ExifTool::MPEG::ParseMPEGAudioVideo($et, $dataPt); } elsif ($type == 0x03 or $type == 0x04) { # MPEG-1/MPEG-2 Audio require Image::ExifTool::MPEG; Image::ExifTool::MPEG::ParseMPEGAudio($et, $dataPt); } elsif ($type == 0x1b) { # H.264 Video require Image::ExifTool::H264; $more = Image::ExifTool::H264::ParseH264Video($et, $dataPt); # force parsing additional H264 frames with ExtractEmbedded option if ($$et{OPTIONS}{ExtractEmbedded}) { $more = 1; } elsif (not $$et{OPTIONS}{Validate}) { $et->WarnOnce('The ExtractEmbedded option may find more tags in the video data',3); } } elsif ($type == 0x81 or $type == 0x87 or $type == 0x91) { # AC-3 audio ParseAC3Audio($et, $dataPt); } elsif ($type == 0x15) { # packetized metadata (look for MISB code starting after 5-byte header) if ($$dataPt =~ /^.{5}\x06\x0e\x2b\x34/s) { $more = Image::ExifTool::MISB::ParseMISB($et, $dataPt, GetTagTable('Image::ExifTool::MISB::Main')); if (not $$et{OPTIONS}{ExtractEmbedded}) { $more = 0; # extract from only the first packet unless ExtractEmbedded is used } elsif ($$et{OPTIONS}{ExtractEmbedded} > 2) { $more = 1; # read past unknown 0x15 packets if ExtractEmbedded > 2 } } } elsif ($type < 0) { if ($$dataPt =~ /^(.{164})?(.{24})A[NS][EW]/s) { # (Blueskysea B4K, Novatek NT96670) # 0000: 01 00 ff 00 30 31 32 33 34 35 37 38 61 62 63 64 [....01234578abcd] # 0010: 65 66 67 0a 00 00 00 00 00 00 00 00 00 00 00 00 [efg.............] # 0020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [................] # 0030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [................] # 0040: 00 00 00 00 30 31 32 33 34 35 37 38 71 77 65 72 [....01234578qwer] # 0050: 74 79 75 69 6f 70 0a 00 00 00 00 00 00 00 00 00 [tyuiop..........] # 0060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [................] # 0070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [................] # 0080: 00 00 00 00 63 38 61 61 32 35 63 66 34 35 65 65 [....c8aa25cf45ee] # 0090: 61 39 65 32 34 34 32 66 61 65 62 35 65 30 39 39 [a9e2442faeb5e099] # 00a0: 30 37 64 34 15 00 00 00 10 00 00 00 1b 00 00 00 [07d4............] # 00b0: 15 00 00 00 01 00 00 00 09 00 00 00 41 4e 57 00 [............ANW.] # 00c0: 82 9a 57 45 98 b2 00 46 66 66 e4 41 d7 e3 14 43 [..WE...Fff.A...C] # 00d0: 01 00 02 00 03 00 04 00 05 00 06 00 [............] # (Viofo A119V3) # 0000: 08 00 00 00 07 00 00 00 18 00 00 00 15 00 00 00 [................] # 0010: 03 00 00 00 0b 00 00 00 41 4e 45 00 01 f2 ac 45 [........ANE....E] # 0020: 2d 7f 6e 45 b8 1e 97 41 d7 23 46 43 00 00 00 00 [-.nE...A.#FC....] # pad with dummy header and parse with existing FreeGPS code (minimum 92 bytes) my $dat = ("\0" x 16) . substr($$dataPt, length($1 || '')) . ("\0" x 20); my $tbl = GetTagTable('Image::ExifTool::QuickTime::Stream'); Image::ExifTool::QuickTime::ProcessFreeGPS($et, { DataPt => \$dat }, $tbl); $more = 1; } elsif ($$dataPt =~ /^A([NS])([EW])\0/s) { # INNOVV TS video (same format is INNOVV MP4) SetByteOrder('II'); my $tagTbl = GetTagTable('Image::ExifTool::QuickTime::Stream'); while ($$dataPt =~ /(A[NS][EW]\0.{28})/g) { my $dat = $1; my $lat = abs(GetFloat(\$dat, 4)); # (abs just to be safe) my $lon = abs(GetFloat(\$dat, 8)); # (abs just to be safe) my $spd = GetFloat(\$dat, 12) * $knotsToKph; my $trk = GetFloat(\$dat, 16); my @acc = unpack('x20V3', $dat); map { $_ = $_ - 4294967296 if $_ >= 0x80000000 } @acc; Image::ExifTool::QuickTime::ConvertLatLon($lat, $lon); $$et{DOC_NUM} = ++$$et{DOC_COUNT}; $et->HandleTag($tagTbl, GPSLatitude => abs($lat) * (substr($dat,1,1) eq 'S' ? -1 : 1)); $et->HandleTag($tagTbl, GPSLongitude => abs($lon) * (substr($dat,2,1) eq 'W' ? -1 : 1)); $et->HandleTag($tagTbl, GPSSpeed => $spd); $et->HandleTag($tagTbl, GPSSpeedRef => 'K'); $et->HandleTag($tagTbl, GPSTrack => $trk); $et->HandleTag($tagTbl, GPSTrackRef => 'T'); $et->HandleTag($tagTbl, Accelerometer => "@acc"); } SetByteOrder('MM'); $more = 1; } elsif ($$dataPt =~ /^\$(GPSINFO|GSNRINFO),/) { # $GPSINFO,0x0004,2021.08.09 13:27:36,2341.54561,12031.70135,8.0,51,153,0,0,\x0d # $GSNRINFO,0.01,0.04,0.25\0 $$dataPt =~ tr/\x0d/\x0a/; $$dataPt =~ tr/\0//d; my $tagTbl = GetTagTable('Image::ExifTool::QuickTime::Stream'); my @lines = split /\x0a/, $$dataPt; my ($line, $lastTime); foreach $line (@lines) { if ($line =~ /^\$GPSINFO/) { my @a = split /,/, $lines[0]; next unless @a > 7; # ignore duplicate fixes next if $lastTime and $a[2] eq $lastTime; $lastTime = $a[2]; $$et{DOC_NUM} = ++$$et{DOC_COUNT}; $a[2] =~ tr/./:/; # (untested, and probably doesn't work for S/W hemispheres) my ($lat, $lon) = @a[3,4]; Image::ExifTool::QuickTime::ConvertLatLon($lat, $lon); # $a[0] - flags? values: '0x0001','0x0004','0x0008','0x0010' $et->HandleTag($tagTbl, GPSDateTime => $a[2]); $et->HandleTag($tagTbl, GPSLatitude => $lat); $et->HandleTag($tagTbl, GPSLongitude => $lon); $et->HandleTag($tagTbl, GPSSpeed => $a[5]); $et->HandleTag($tagTbl, GPSSpeedRef => 'K'); # $a[6] - values: 48-60 $et->HandleTag($tagTbl, GPSTrack => $a[7]); $et->HandleTag($tagTbl, GPSTrackRef => 'T'); # #a[8,9] - always 0 } elsif ($line =~ /^\$GSNRINFO/) { my @a = split /,/, $line; shift @a; $et->HandleTag($tagTbl, Accelerometer => "@a"); } } $more = 1; } elsif ($$dataPt =~ /\$GPRMC,/) { # Jomise T860S-GM dashcam # $GPRMC,hhmmss.ss,A,ddmm.mmmmm,N,dddmm.mmmmm,W,spd-kts,dir-dg,DDMMYY,,*cs # $GPRMC,172255.00,A,:985.95194,N,17170.14674,W,029.678,170.68,240822,,,D*7B # $GPRMC,172355.00,A,:984.76779,N,17170.00473,W,032.219,172.04,240822,,,D*7B # ddmm.mmmm: from 4742.2568 12209.2028 (should be) # to 4741.7696 12209.1056 # stamped on video: 47.70428N, 122.15338W, 35mph (dd.ddddd) # to 47.69616N, 122.15176W, 37mph my $tagTbl = GetTagTable('Image::ExifTool::QuickTime::Stream'); while ($$dataPt =~ /\$[A-Z]{2}RMC,(\d{2})(\d{2})(\d+(\.\d*)?),A?,(.{2})(\d{2}\.\d+),([NS]),(.{3})(\d{2}\.\d+),([EW]),(\d*\.?\d*),(\d*\.?\d*),(\d{2})(\d{2})(\d+)/g and # do some basic sanity checks on the date $13 <= 31 and $14 <= 12 and $15 <= 99) { $$et{DOC_NUM} = ++$$et{DOC_COUNT}; my $year = $15 + ($15 >= 70 ? 1900 : 2000); $et->HandleTag($tagTbl, GPSDateTime => sprintf('%.4d:%.2d:%.2d %.2d:%.2d:%.2dZ', $year, $14, $13, $1, $2, $3)); #(not this simple) #$et->HandleTag($tagTbl, GPSLatitude => (($5 || 0) + $6/60) * ($7 eq 'N' ? 1 : -1)); #$et->HandleTag($tagTbl, GPSLongitude => (($8 || 0) + $9/60) * ($10 eq 'E' ? 1 : -1)); $et->HandleTag($tagTbl, GPSSpeed => $11 * $knotsToKph) if length $11; $et->HandleTag($tagTbl, GPSTrack => $12) if length $12; # it looks like maybe the degrees are xor-ed with something, # and the minutes have some scaling factor and offset? # (the code below is approximately correct for my only sample) my @chars = unpack('C*', $5 . $8); my @xor = (0x0e,0x0e,0x00,0x05,0x03); # (empirical based on 1 sample; may be completely off base) my $bad; foreach (@chars) { $_ ^= shift(@xor); $bad = 1 if $_ < 0x30 or $_ > 0x39; } if ($bad) { $et->WarnOnce('Error decrypting GPS degrees'); } else { my $la = pack('C*', @chars[0,1]); my $lo = pack('C*', @chars[2,3,4]); $et->WarnOnce('Decryption of this GPS is highly experimental. More testing samples are required'); $et->HandleTag($tagTbl, GPSLatitude => (($la || 0) + (($6-85.95194)/2.43051724137931+42.2568)/60) * ($7 eq 'N' ? 1 : -1)); $et->HandleTag($tagTbl, GPSLongitude => (($lo || 0) + (($9-70.14674)/1.460987654320988+9.2028)/60) * ($10 eq 'E' ? 1 : -1)); } } } elsif ($$dataPt =~ /^.{44}A\0{3}.{4}([NS])\0{3}.{4}([EW])\0{3}/s and length($$dataPt) >= 84) { #forum11320 SetByteOrder('II'); my $tagTbl = GetTagTable('Image::ExifTool::QuickTime::Stream'); my $lat = abs(GetFloat($dataPt, 48)); # (abs just to be safe) my $lon = abs(GetFloat($dataPt, 56)); # (abs just to be safe) my $spd = GetFloat($dataPt, 64); my $trk = GetFloat($dataPt, 68); $et->WarnOnce('GPSLatitude/Longitude encryption is not yet known, so these will be wrong'); $$et{DOC_NUM} = ++$$et{DOC_COUNT}; my @date = unpack('x32V3x28V3', $$dataPt); $date[3] += 2000; $et->HandleTag($tagTbl, GPSDateTime => sprintf('%.4d:%.2d:%.2d %.2d:%.2d:%.2d', @date[3..5,0..2])); $et->HandleTag($tagTbl, GPSLatitude => abs($lat) * ($1 eq 'S' ? -1 : 1)); $et->HandleTag($tagTbl, GPSLongitude => abs($lon) * ($2 eq 'W' ? -1 : 1)); $et->HandleTag($tagTbl, GPSSpeed => $spd); $et->HandleTag($tagTbl, GPSSpeedRef => 'K'); $et->HandleTag($tagTbl, GPSTrack => $trk); $et->HandleTag($tagTbl, GPSTrackRef => 'T'); SetByteOrder('MM'); $more = 1; } delete $$et{DOC_NUM}; } return $more; } #------------------------------------------------------------------------------ # Extract information from a M2TS file # Inputs: 0) ExifTool object reference, 1) DirInfo reference # Returns: 1 on success, 0 if this wasn't a valid M2TS file sub ProcessM2TS($$) { my ($et, $dirInfo) = @_; my $raf = $$dirInfo{RAF}; my ($buff, $pLen, $upkPrefix, $j, $fileType, $eof); my (%pmt, %pidType, %data, %sectLen, %packLen, %fromStart); my ($startTime, $endTime, $fwdTime, $backScan, $maxBack); my $verbose = $et->Options('Verbose'); my $out = $et->Options('TextOut'); # read first packet return 0 unless $raf->Read($buff, 8) == 8; # test for magic number (sync byte is the only thing we can safely check) return 0 unless $buff =~ /^(....)?\x47/s; unless ($1) { $pLen = 188; # no timecode $fileType = 'M2T'; # (just as a way to tell there is no timecode) $upkPrefix = 'N'; } else { $pLen = 192; # 188-byte transport packet + leading 4-byte timecode (ref 4) $upkPrefix = 'x4N'; } my $prePos = $pLen - 188; # byte position of packet prefix my $readSize = 64 * $pLen; # size of our read buffer $raf->Seek(0,0); # rewind to start $raf->Read($buff, $readSize) >= $pLen * 4 or return 0; # require at least 4 packets # validate the sync byte in the next 3 packets for ($j=1; $j<4; ++$j) { return 0 unless substr($buff, $prePos + $pLen * $j, 1) eq 'G'; # (0x47) } $et->SetFileType($fileType); SetByteOrder('MM'); my $tagTablePtr = GetTagTable('Image::ExifTool::M2TS::Main'); # PID lookup strings (will add to this with entries from program map table) my %pidName = ( 0 => 'Program Association Table', 1 => 'Conditional Access Table', 2 => 'Transport Stream Description Table', 0x1fff => 'Null Packet', ); my %didPID = ( 1 => 0, 2 => 0, 0x1fff => 0 ); my %needPID = ( 0 => 1 ); # lookup for stream PID's that we still need to parse # PID's that may contain GPS info my %gpsPID = ( 0x0300 => 1, # Novatek INNOVV 0x01e4 => 1, # vsys a6l dashcam 0x0e1b => 1, # Jomise T860S-GM dashcam ); my $pEnd = 0; # scan entire file for GPS programs if ExtractEmbedded option is 3 or higher # (some dashcams write these programs but don't include it in the PMT) if (($et->Options('ExtractEmbedded') || 0) > 2) { foreach (keys %gpsPID) { $needPID{$_} = 1; $pidType{$_} = -1; $pidName{$_} ='unregistered dashcam GPS'; } } # parse packets from MPEG-2 Transport Stream for (;;) { unless (%needPID) { last unless defined $startTime; # reconfigure to seek backwards for last PCR unless (defined $backScan) { my $saveTime = $endTime; undef $endTime; last if $et->Options('FastScan'); $verbose and print $out "[Starting backscan for last PCR]\n"; # remember how far we got when reading forward through the file my $fwdPos = $raf->Tell() - length($buff) + $pEnd; # determine the position of the last packet relative to the EOF $raf->Seek(0, 2) or last; my $fsize = $raf->Tell(); $backScan = int($fsize / $pLen) * $pLen - $fsize; # set limit on how far back we will go $maxBack = $fwdPos - $fsize; # scan back a maximum of 512k (have seen last PCR at -276k) my $nMax = int(512000 / $pLen); # max packets to backscan if ($nMax < int(-$maxBack / $pLen)) { $maxBack = $backScan - $nMax * $pLen; } else { # use this time if none found in all remaining packets $fwdTime = $saveTime; } $pEnd = 0; } } my $pos; # read more if necessary if (defined $backScan) { last if defined $endTime; $pos = $pEnd = $pEnd - 2 * $pLen; # step back to previous packet if ($pos < 0) { # read another buffer from end of file last if $backScan <= $maxBack; my $buffLen = $backScan - $maxBack; $buffLen = $readSize if $buffLen > $readSize; $backScan -= $buffLen; $raf->Seek($backScan, 2) or last; $raf->Read($buff, $buffLen) == $buffLen or last; $pos = $pEnd = $buffLen - $pLen; } } else { $pos = $pEnd; if ($pos + $pLen > length $buff) { $raf->Read($buff, $readSize) >= $pLen or $eof = 1, last; $pos = $pEnd = 0; } } $pEnd += $pLen; # decode the packet prefix $pos += $prePos; my $prefix = unpack("x${pos}N", $buff); # (use unpack instead of Get32u for speed) # validate sync byte unless (($prefix & 0xff000000) == 0x47000000) { $et->Warn('M2TS synchronization error') unless defined $backScan; last; } # my $transport_error_indicator = $prefix & 0x00800000; my $payload_unit_start_indicator = $prefix & 0x00400000; # my $transport_priority = $prefix & 0x00200000; my $pid =($prefix & 0x001fff00) >> 8; # packet ID # my $transport_scrambling_control = $prefix & 0x000000c0; my $adaptation_field_exists = $prefix & 0x00000020; my $payload_data_exists = $prefix & 0x00000010; # my $continuity_counter = $prefix & 0x0000000f; if ($verbose > 1) { my $i = ($raf->Tell() - length($buff) + $pEnd) / $pLen - 1; print $out "Transport packet $i:\n"; $et->VerboseDump(\$buff, Len => $pLen, Addr => $i * $pLen, Start => $pos - $prePos); my $str = $pidName{$pid} ? " ($pidName{$pid})" : ' '; printf $out " Timecode: 0x%.4x\n", Get32u(\$buff, $pos - $prePos) if $pLen == 192; printf $out " Packet ID: 0x%.4x$str\n", $pid; printf $out " Start Flag: %s\n", $payload_unit_start_indicator ? 'Yes' : 'No'; } $pos += 4; # handle adaptation field if ($adaptation_field_exists) { my $len = Get8u(\$buff, $pos++); $pos + $len > $pEnd and $et->Warn('Invalid adaptation field length'), last; # read PCR value for calculation of Duration if ($len > 6) { my $flags = Get8u(\$buff, $pos); if ($flags & 0x10) { # PCR_flag # combine 33-bit program_clock_reference_base and 9-bit extension my $pcrBase = Get32u(\$buff, $pos + 1); my $pcrExt = Get16u(\$buff, $pos + 5); # ignore separate programs (PID's) and store just the # first and last timestamps found in the file (is this OK?) $endTime = 300 * (2 * $pcrBase + ($pcrExt >> 15)) + ($pcrExt & 0x01ff); $startTime = $endTime unless defined $startTime; } } $pos += $len; } # all done with this packet unless it carries a payload # or if we are just looking for the last timestamp next unless $payload_data_exists and not defined $backScan; # decode payload data if ($pid == 0 or # program association table defined $pmt{$pid}) # program map table(s) { # must interpret pointer field if payload_unit_start_indicator is set my $buf2; if ($payload_unit_start_indicator) { # skip to start of section my $pointer_field = Get8u(\$buff, $pos); $pos += 1 + $pointer_field; $pos >= $pEnd and $et->Warn('Bad pointer field'), last; $buf2 = substr($buff, $pEnd-$pLen, $pLen); $pos -= $pEnd - $pLen; } else { # not the start of a section next unless $sectLen{$pid}; my $more = $sectLen{$pid} - length($data{$pid}); my $size = $pLen - $pos; $size = $more if $size > $more; $data{$pid} .= substr($buff, $pos, $size); next unless $size == $more; # we have the complete section now, so put into $buf2 for parsing $buf2 = $data{$pid}; $pos = 0; delete $data{$pid}; delete $fromStart{$pid}; delete $sectLen{$pid}; } my $slen = length($buf2); # section length $pos + 8 > $slen and $et->Warn('Truncated payload'), last; # validate table ID my $table_id = Get8u(\$buf2, $pos); my $name = ($tableID{$table_id} || sprintf('Unknown (0x%x)',$table_id)) . ' Table'; my $expectedID = $pid ? 0x02 : 0x00; unless ($table_id == $expectedID) { $verbose > 1 and print $out " (skipping $name)\n"; delete $needPID{$pid}; $didPID{$pid} = 1; next; } # validate section syntax indicator for parsed tables (PAT, PMT) my $section_syntax_indicator = Get8u(\$buf2, $pos + 1) & 0xc0; $section_syntax_indicator == 0x80 or $et->Warn("Bad $name"), last; my $section_length = Get16u(\$buf2, $pos + 1) & 0x0fff; $section_length > 1021 and $et->Warn("Invalid $name length"), last; if ($slen < $section_length + 3) { # (3 bytes for table_id + section_length) # must wait until we have the full section $data{$pid} = substr($buf2, $pos); $sectLen{$pid} = $section_length + 3; next; } my $program_number = Get16u(\$buf2, $pos + 3); my $section_number = Get8u(\$buf2, $pos + 6); my $last_section_number = Get8u(\$buf2, $pos + 7); if ($verbose > 1) { print $out " $name length: $section_length\n"; print $out " Program No: $program_number\n" if $pid; printf $out " Stream ID: 0x%x\n", $program_number if not $pid; print $out " Section No: $section_number\n"; print $out " Last Sect.: $last_section_number\n"; } my $end = $pos + $section_length + 3 - 4; # (don't read 4-byte CRC) $pos += 8; if ($pid == 0) { # decode PAT (Program Association Table) while ($pos <= $end - 4) { my $program_number = Get16u(\$buf2, $pos); my $program_map_PID = Get16u(\$buf2, $pos + 2) & 0x1fff; $pmt{$program_map_PID} = $program_number; # save our PMT PID's my $str = "Program $program_number Map"; $pidName{$program_map_PID} = $str; $needPID{$program_map_PID} = 1 unless $didPID{$program_map_PID}; $verbose and printf $out " PID(0x%.4x) --> $str\n", $program_map_PID; $pos += 4; } } else { # decode PMT (Program Map Table) $pos + 4 > $slen and $et->Warn('Truncated PMT'), last; my $pcr_pid = Get16u(\$buf2, $pos) & 0x1fff; my $program_info_length = Get16u(\$buf2, $pos + 2) & 0x0fff; my $str = "Program $program_number Clock Reference"; $pidName{$pcr_pid} = $str; $verbose and printf $out " PID(0x%.4x) --> $str\n", $pcr_pid; $pos += 4; $pos + $program_info_length > $slen and $et->Warn('Truncated program info'), last; # dump program information descriptors if verbose if ($verbose > 1) { for ($j=0; $j<$program_info_length-2; ) { my $descriptor_tag = Get8u(\$buf2, $pos + $j); my $descriptor_length = Get8u(\$buf2, $pos + $j + 1); $j += 2; last if $j + $descriptor_length > $program_info_length; my $desc = substr($buf2, $pos+$j, $descriptor_length); $j += $descriptor_length; $desc =~ s/([\x00-\x1f\x80-\xff])/sprintf("\\x%.2x",ord $1)/eg; printf $out " Program Descriptor: Type=0x%.2x \"$desc\"\n", $descriptor_tag; }} $pos += $program_info_length; # skip descriptors (for now) while ($pos <= $end - 5) { my $stream_type = Get8u(\$buf2, $pos); my $elementary_pid = Get16u(\$buf2, $pos + 1) & 0x1fff; my $es_info_length = Get16u(\$buf2, $pos + 3) & 0x0fff; my $str = $streamType{$stream_type}; $str or $str = ($stream_type < 0x7f ? 'Reserved' : 'Private'); $str = sprintf('%s (0x%.2x)', $str, $stream_type); $str = "Program $program_number $str"; $verbose and printf $out " PID(0x%.4x) --> $str\n", $elementary_pid; if ($str =~ /(Audio|Video)/) { unless ($pidName{$elementary_pid}) { $et->HandleTag($tagTablePtr, $1 . 'StreamType', $stream_type) } # we want to parse all Audio and Video streams $needPID{$elementary_pid} = 1 unless $didPID{$elementary_pid}; } # save PID type and name string $pidName{$elementary_pid} = $str; $pidType{$elementary_pid} = $stream_type; $pos += 5; $pos + $es_info_length > $slen and $et->Warn('Truncated ES info'), $pos = $end, last; # parse elementary stream descriptors for ($j=0; $j<$es_info_length-2; ) { my $descriptor_tag = Get8u(\$buf2, $pos + $j); my $descriptor_length = Get8u(\$buf2, $pos + $j + 1); $j += 2; last if $j + $descriptor_length > $es_info_length; my $desc = substr($buf2, $pos+$j, $descriptor_length); $j += $descriptor_length; if ($verbose > 1) { my $dstr = $desc; $dstr =~ s/([\x00-\x1f\x80-\xff])/sprintf("\\x%.2x",ord $1)/eg; printf $out " ES Descriptor: Type=0x%.2x \"$dstr\"\n", $descriptor_tag; } # parse type-specific descriptor information (once) unless ($didPID{$pid}) { if ($descriptor_tag == 0x81) { # AC-3 ParseAC3Descriptor($et, \$desc); } } } $pos += $es_info_length; } } # $pos = $end + 4; # skip CRC } elsif (not defined $didPID{$pid}) { # save data from the start of each elementary stream if ($payload_unit_start_indicator) { if (defined $data{$pid}) { # we must have a whole section, so parse now my $more = ParsePID($et, $pid, $pidType{$pid}, $pidName{$pid}, \$data{$pid}); # start fresh even if we couldn't process this PID yet delete $data{$pid}; delete $fromStart{$pid}; unless ($more) { delete $needPID{$pid}; $didPID{$pid} = 1; next; } # set flag indicating we found this PID but we still want more $needPID{$pid} = -1; } # check for a PES header next if $pos + 6 > $pEnd; my $start_code = Get32u(\$buff, $pos); next unless ($start_code & 0xffffff00) == 0x00000100; my $stream_id = $start_code & 0xff; my $pes_packet_length = Get16u(\$buff, $pos + 4); if ($verbose > 1) { printf $out " Stream ID: 0x%.2x\n", $stream_id; print $out " Packet Len: $pes_packet_length\n"; } $pos += 6; unless ($noSyntax{$stream_id}) { next if $pos + 3 > $pEnd; # validate PES syntax my $syntax = Get8u(\$buff, $pos) & 0xc0; $syntax == 0x80 or $et->Warn('Bad PES syntax'), next; # skip PES header my $pes_header_data_length = Get8u(\$buff, $pos + 2); $pos += 3 + $pes_header_data_length; next if $pos >= $pEnd; } $data{$pid} = substr($buff, $pos, $pEnd-$pos); # set flag that we read this payload from the start $fromStart{$pid} = 1; # save the packet length if ($pes_packet_length > 8) { $packLen{$pid} = $pes_packet_length - 8; # (where are the 8 extra bytes? - PH) } else { delete $packLen{$pid}; } } else { unless (defined $data{$pid}) { # (vsys a6l dashcam GPS record doesn't have a start indicator) next unless $gpsPID{$pid}; $data{$pid} = ''; } # accumulate data for each elementary stream $data{$pid} .= substr($buff, $pos, $pEnd-$pos); } # save only the first 256 bytes of most streams, except for # unknown, H.264 or metadata streams where we save up to 1 kB my $saveLen; if (not $pidType{$pid} or $pidType{$pid} == 0x1b) { $saveLen = 1024; } elsif ($pidType{$pid} == 0x15) { # use 1024 or actual size of metadata packet if smaller $saveLen = 1024; $saveLen = $packLen{$pid} if defined $packLen{$pid} and $saveLen > $packLen{$pid}; } else { $saveLen = 256; } if (length($data{$pid}) >= $saveLen) { my $more = ParsePID($et, $pid, $pidType{$pid}, $pidName{$pid}, \$data{$pid}); next if $more < 0; # wait for program map table (hopefully not too long) # don't stop parsing if we weren't successful and may have missed the start $more = 1 if not $more and not $fromStart{$pid}; delete $data{$pid}; delete $fromStart{$pid}; $more and $needPID{$pid} = -1, next; # parse more of these delete $needPID{$pid}; $didPID{$pid} = 1; } next; } if ($needPID{$pid}) { # we found and parsed a section with this PID, so # delete from the lookup of PID's we still need to parse delete $needPID{$pid}; $didPID{$pid} = 1; } } # calculate Duration if available $endTime = $fwdTime unless defined $endTime; if (defined $startTime and defined $endTime) { $endTime += 0x80000000 * 1200 if $startTime > $endTime; # handle 33-bit wrap $et->HandleTag($tagTablePtr, 'Duration', $endTime - $startTime); } if ($verbose) { my @need; foreach (keys %needPID) { push @need, sprintf('0x%.2x',$_) if $needPID{$_} > 0; } if (@need) { @need = sort @need; print $out "End of file. Missing PID(s): @need\n"; } else { my $what = $eof ? 'of file' : 'scan'; print $out "End $what. All PID's parsed.\n"; } } # parse any remaining partial PID streams my $pid; foreach $pid (sort keys %data) { ParsePID($et, $pid, $pidType{$pid}, $pidName{$pid}, \$data{$pid}); delete $data{$pid}; } return 1; } 1; # end __END__ =head1 NAME Image::ExifTool::M2TS - Read M2TS (AVCHD) meta information =head1 SYNOPSIS This module is used by Image::ExifTool =head1 DESCRIPTION This module contains routines required by Image::ExifTool to extract information from MPEG-2 transport streams, such as those used by AVCHD video. =head1 AUTHOR Copyright 2003-2023, Phil Harvey (philharvey66 at gmail.com) This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. =head1 REFERENCES =over 4 =item L =item L =item L =item L =item L =item L =item L =item L =back =head1 SEE ALSO L, L =cut