Tester utilities
This commit is contained in:
@@ -0,0 +1,736 @@
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#------------------------------------------------------------------------------
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# File: MPEG.pm
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#
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# Description: Read MPEG-1 and MPEG-2 meta information
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#
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# Revisions: 05/11/2006 - P. Harvey Created
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#
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# References: 1) http://www.mp3-tech.org/
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# 2) http://www.getid3.org/
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# 3) http://dvd.sourceforge.net/dvdinfo/dvdmpeg.html
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# 4) http://ffmpeg.org/
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# 5) http://sourceforge.net/projects/mediainfo/
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#------------------------------------------------------------------------------
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package Image::ExifTool::MPEG;
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use strict;
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use vars qw($VERSION);
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use Image::ExifTool qw(:DataAccess :Utils);
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$VERSION = '1.15';
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%Image::ExifTool::MPEG::Audio = (
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GROUPS => { 2 => 'Audio' },
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'Bit11-12' => {
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Name => 'MPEGAudioVersion',
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RawConv => '$self->{MPEG_Vers} = $val',
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PrintConv => {
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0 => 2.5,
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2 => 2,
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3 => 1,
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},
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},
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'Bit13-14' => {
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Name => 'AudioLayer',
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RawConv => '$self->{MPEG_Layer} = $val',
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PrintConv => {
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1 => 3,
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2 => 2,
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3 => 1,
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},
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},
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# Bit 15 indicates CRC protection
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'Bit16-19' => [
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{
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Name => 'AudioBitrate',
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Condition => '$self->{MPEG_Vers} == 3 and $self->{MPEG_Layer} == 3',
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Notes => 'version 1, layer 1',
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PrintConvColumns => 3,
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ValueConv => {
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0 => 'free',
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1 => 32000,
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2 => 64000,
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3 => 96000,
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4 => 128000,
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5 => 160000,
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6 => 192000,
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7 => 224000,
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8 => 256000,
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9 => 288000,
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10 => 320000,
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11 => 352000,
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12 => 384000,
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13 => 416000,
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14 => 448000,
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},
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PrintConv => 'ConvertBitrate($val)',
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},
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{
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Name => 'AudioBitrate',
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Condition => '$self->{MPEG_Vers} == 3 and $self->{MPEG_Layer} == 2',
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Notes => 'version 1, layer 2',
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PrintConvColumns => 3,
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ValueConv => {
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0 => 'free',
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1 => 32000,
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2 => 48000,
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3 => 56000,
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4 => 64000,
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5 => 80000,
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6 => 96000,
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7 => 112000,
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8 => 128000,
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9 => 160000,
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10 => 192000,
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11 => 224000,
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12 => 256000,
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13 => 320000,
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14 => 384000,
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},
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PrintConv => 'ConvertBitrate($val)',
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},
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{
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Name => 'AudioBitrate',
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Condition => '$self->{MPEG_Vers} == 3 and $self->{MPEG_Layer} == 1',
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Notes => 'version 1, layer 3',
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PrintConvColumns => 3,
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ValueConv => {
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0 => 'free',
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1 => 32000,
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2 => 40000,
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3 => 48000,
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4 => 56000,
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5 => 64000,
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6 => 80000,
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7 => 96000,
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8 => 112000,
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9 => 128000,
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10 => 160000,
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11 => 192000,
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12 => 224000,
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13 => 256000,
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14 => 320000,
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},
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PrintConv => 'ConvertBitrate($val)',
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},
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{
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Name => 'AudioBitrate',
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Condition => '$self->{MPEG_Vers} != 3 and $self->{MPEG_Layer} == 3',
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Notes => 'version 2 or 2.5, layer 1',
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PrintConvColumns => 3,
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ValueConv => {
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0 => 'free',
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1 => 32000,
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2 => 48000,
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3 => 56000,
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4 => 64000,
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5 => 80000,
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6 => 96000,
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7 => 112000,
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8 => 128000,
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9 => 144000,
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10 => 160000,
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11 => 176000,
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12 => 192000,
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13 => 224000,
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14 => 256000,
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},
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PrintConv => 'ConvertBitrate($val)',
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},
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{
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Name => 'AudioBitrate',
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Condition => '$self->{MPEG_Vers} != 3 and $self->{MPEG_Layer}',
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Notes => 'version 2 or 2.5, layer 2 or 3',
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PrintConvColumns => 3,
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ValueConv => {
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0 => 'free',
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1 => 8000,
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2 => 16000,
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3 => 24000,
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4 => 32000,
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5 => 40000,
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6 => 48000,
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7 => 56000,
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8 => 64000,
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9 => 80000,
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10 => 96000,
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11 => 112000,
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12 => 128000,
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13 => 144000,
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14 => 160000,
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},
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PrintConv => 'ConvertBitrate($val)',
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},
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],
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'Bit20-21' => [
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{
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Name => 'SampleRate',
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Condition => '$self->{MPEG_Vers} == 3',
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Notes => 'version 1',
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PrintConv => {
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0 => 44100,
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1 => 48000,
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2 => 32000,
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},
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},
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{
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Name => 'SampleRate',
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Condition => '$self->{MPEG_Vers} == 2',
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Notes => 'version 2',
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PrintConv => {
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0 => 22050,
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1 => 24000,
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2 => 16000,
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},
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},
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{
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Name => 'SampleRate',
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Condition => '$self->{MPEG_Vers} == 0',
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Notes => 'version 2.5',
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PrintConv => {
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0 => 11025,
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1 => 12000,
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2 => 8000,
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},
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},
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],
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# Bit 22 - padding flag
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# Bit 23 - private bit
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'Bit24-25' => {
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Name => 'ChannelMode',
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RawConv => '$self->{MPEG_Mode} = $val',
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PrintConv => {
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0 => 'Stereo',
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1 => 'Joint Stereo',
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2 => 'Dual Channel',
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3 => 'Single Channel',
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},
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},
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'Bit26' => {
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Name => 'MSStereo',
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Condition => '$self->{MPEG_Layer} == 1',
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Notes => 'layer 3',
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PrintConv => { 0 => 'Off', 1 => 'On' },
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},
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'Bit27' => {
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Name => 'IntensityStereo',
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Condition => '$self->{MPEG_Layer} == 1',
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Notes => 'layer 3',
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PrintConv => { 0 => 'Off', 1 => 'On' },
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},
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'Bit26-27' => {
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Name => 'ModeExtension',
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Condition => '$self->{MPEG_Layer} > 1',
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Notes => 'layer 1 or 2',
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PrintConv => {
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0 => 'Bands 4-31',
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1 => 'Bands 8-31',
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2 => 'Bands 12-31',
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3 => 'Bands 16-31',
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},
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},
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'Bit28' => {
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Name => 'CopyrightFlag',
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PrintConv => {
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0 => 'False',
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1 => 'True',
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},
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},
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'Bit29' => {
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Name => 'OriginalMedia',
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PrintConv => {
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0 => 'False',
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1 => 'True',
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},
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},
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'Bit30-31' => {
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Name => 'Emphasis',
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PrintConv => {
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0 => 'None',
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1 => '50/15 ms',
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2 => 'reserved',
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3 => 'CCIT J.17',
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},
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},
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);
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%Image::ExifTool::MPEG::Video = (
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GROUPS => { 2 => 'Video' },
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'Bit00-11' => 'ImageWidth',
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'Bit12-23' => 'ImageHeight',
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'Bit24-27' => {
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Name => 'AspectRatio',
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ValueConv => {
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1 => 1,
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2 => 0.6735,
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3 => 0.7031,
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4 => 0.7615,
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5 => 0.8055,
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6 => 0.8437,
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7 => 0.8935,
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8 => 0.9157,
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9 => 0.9815,
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10 => 1.0255,
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11 => 1.0695,
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12 => 1.0950,
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13 => 1.1575,
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14 => 1.2015,
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},
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PrintConv => {
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1 => '1:1',
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0.6735 => '0.6735',
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0.7031 => '16:9, 625 line, PAL',
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0.7615 => '0.7615',
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0.8055 => '0.8055',
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0.8437 => '16:9, 525 line, NTSC',
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0.8935 => '0.8935',
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0.9157 => '4:3, 625 line, PAL, CCIR601',
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0.9815 => '0.9815',
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1.0255 => '1.0255',
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1.0695 => '1.0695',
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1.0950 => '4:3, 525 line, NTSC, CCIR601',
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1.1575 => '1.1575',
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1.2015 => '1.2015',
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},
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},
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'Bit28-31' => {
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Name => 'FrameRate',
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ValueConv => {
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1 => 23.976,
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2 => 24,
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3 => 25,
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4 => 29.97,
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5 => 30,
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6 => 50,
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7 => 59.94,
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8 => 60,
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},
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PrintConv => '"$val fps"',
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},
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'Bit32-49' => {
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Name => 'VideoBitrate',
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ValueConv => '$val eq 0x3ffff ? "Variable" : $val * 400',
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PrintConv => 'ConvertBitrate($val)',
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},
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# these tags not very interesting
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#'Bit50' => 'MarkerBit',
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#'Bit51-60' => 'VBVBufferSize',
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#'Bit61' => 'ConstrainedParamFlag',
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#'Bit62' => 'IntraQuantMatrixFlag',
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);
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%Image::ExifTool::MPEG::Xing = (
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GROUPS => { 2 => 'Audio' },
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VARS => { NO_ID => 1 },
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NOTES => 'These tags are extracted from the Xing/Info frame.',
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1 => { Name => 'VBRFrames' },
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2 => { Name => 'VBRBytes' },
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3 => { Name => 'VBRScale' },
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4 => { Name => 'Encoder' },
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5 => { Name => 'LameVBRQuality' },
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6 => { Name => 'LameQuality' },
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7 => { # (for documentation only)
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Name => 'LameHeader',
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SubDirectory => { TagTable => 'Image::ExifTool::MPEG::Lame' },
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},
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);
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# Lame header tags (ref 5)
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%Image::ExifTool::MPEG::Lame = (
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PROCESS_PROC => \&Image::ExifTool::ProcessBinaryData,
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GROUPS => { 2 => 'Audio' },
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NOTES => 'Tags extracted from Lame 3.90 or later header.',
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9 => {
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Name => 'LameMethod',
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Mask => 0x0f,
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PrintConv => {
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1 => 'CBR',
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2 => 'ABR',
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3 => 'VBR (old/rh)',
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4 => 'VBR (new/mtrh)',
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5 => 'VBR (old/rh)',
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6 => 'VBR',
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8 => 'CBR (2-pass)',
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9 => 'ABR (2-pass)',
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},
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},
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10 => {
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Name => 'LameLowPassFilter',
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ValueConv => '$val * 100',
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PrintConv => '($val / 1000) . " kHz"',
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},
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# 19 - EncodingFlags
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20 => {
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Name => 'LameBitrate',
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ValueConv => '$val * 1000',
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PrintConv => 'ConvertBitrate($val)',
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},
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24 => {
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Name => 'LameStereoMode',
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Mask => 0x1c,
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ValueConv => '$val >> 2',
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PrintConv => {
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0 => 'Mono',
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1 => 'Stereo',
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2 => 'Dual Channels',
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3 => 'Joint Stereo',
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4 => 'Forced Joint Stereo',
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6 => 'Auto',
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7 => 'Intensity Stereo',
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},
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},
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);
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# composite tags
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%Image::ExifTool::MPEG::Composite = (
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Duration => {
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Groups => { 2 => 'Video' },
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Require => {
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0 => 'FileSize',
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},
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Desire => {
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1 => 'ID3Size',
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2 => 'MPEG:AudioBitrate',
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3 => 'MPEG:VideoBitrate',
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4 => 'MPEG:VBRFrames',
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5 => 'MPEG:SampleRate',
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6 => 'MPEG:MPEGAudioVersion',
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},
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Priority => -1, # (don't want to replace any other Duration tag)
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ValueConv => q{
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if ($val[4] and defined $val[5] and defined $val[6]) {
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# calculate from number of VBR audio frames
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my $mfs = $prt[5] / ($val[6] == 3 ? 144 : 72);
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# calculate using VBR length
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return 8 * $val[4] / $mfs;
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}
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# calculate duration as file size divided by total bitrate
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# (note: this is only approximate!)
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return undef unless $val[2] or $val[3];
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return undef if $val[2] and not $val[2] =~ /^\d+$/;
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return undef if $val[3] and not $val[3] =~ /^\d+$/;
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return (8 * ($val[0] - ($val[1]||0))) / (($val[2]||0) + ($val[3]||0));
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},
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PrintConv => 'ConvertDuration($val) . " (approx)"',
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},
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AudioBitrate => {
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Groups => { 2 => 'Audio' },
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Notes => 'calculated for variable-bitrate MPEG audio',
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Require => {
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0 => 'MPEG:MPEGAudioVersion',
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1 => 'MPEG:SampleRate',
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2 => 'MPEG:VBRBytes',
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3 => 'MPEG:VBRFrames',
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},
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ValueConv => q{
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return undef unless $val[3];
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my $mfs = $prt[1] / ($val[0] == 3 ? 144 : 72);
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return $mfs * $val[2] / $val[3];
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},
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PrintConv => 'ConvertBitrate($val)',
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},
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);
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# add our composite tags
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Image::ExifTool::AddCompositeTags('Image::ExifTool::MPEG');
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#------------------------------------------------------------------------------
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# Process information in an MPEG audio or video frame header
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# Inputs: 0) ExifTool object ref, 1) tag table ref, 2-N) list of 32-bit data words
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sub ProcessFrameHeader($$@)
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{
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my ($et, $tagTablePtr, @data) = @_;
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my $tag;
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foreach $tag (sort keys %$tagTablePtr) {
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next unless $tag =~ /^Bit(\d{2})-?(\d{2})?/;
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my ($b1, $b2) = ($1, $2 || $1);
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my $index = int($b1 / 32);
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my $word = $data[$index];
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my $mask = 0;
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foreach (0 .. ($b2 - $b1)) {
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$mask += (1 << $_);
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}
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my $val = ($word >> (31 + 32*$index - $b2)) & $mask;
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$et->HandleTag($tagTablePtr, $tag, $val);
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}
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}
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||||
#------------------------------------------------------------------------------
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# Read MPEG audio frame header
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# Inputs: 0) ExifTool object reference, 1) Reference to audio data
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# 2) flag set if we are trying to recognized MP3 file only
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# Returns: 1 on success, 0 if no audio header was found
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sub ParseMPEGAudio($$;$)
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{
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my ($et, $buffPt, $mp3) = @_;
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my ($word, $pos);
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my $ext = $$et{FILE_EXT} || '';
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for (;;) {
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# find frame sync
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return 0 unless $$buffPt =~ m{(\xff.{3})}sg;
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$word = unpack('N', $1); # get audio frame header word
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unless (($word & 0xffe00000) == 0xffe00000) {
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pos($$buffPt) = pos($$buffPt) - 2; # next possible location for frame sync
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next;
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}
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# validate header as much as possible
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if (($word & 0x180000) == 0x080000 or # 01 is a reserved version ID
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($word & 0x060000) == 0x000000 or # 00 is a reserved layer description
|
||||
($word & 0x00f000) == 0x000000 or # 0000 is the "free" bitrate index
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||||
($word & 0x00f000) == 0x00f000 or # 1111 is a bad bitrate index
|
||||
($word & 0x000c00) == 0x000c00 or # 11 is a reserved sampling frequency
|
||||
($word & 0x000003) == 0x000002 or # 10 is a reserved emphasis
|
||||
(($mp3 and ($word & 0x060000) != 0x020000))) # must be layer 3 for MP3
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||||
{
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||||
# give up easily unless this really should be an MP3 file
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||||
return 0 unless $ext eq 'MP3';
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||||
pos($$buffPt) = pos($$buffPt) - 1;
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||||
next;
|
||||
}
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||||
$pos = pos($$buffPt);
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||||
last;
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||||
}
|
||||
# set file type if not done already
|
||||
$et->SetFileType();
|
||||
|
||||
my $tagTablePtr = GetTagTable('Image::ExifTool::MPEG::Audio');
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||||
ProcessFrameHeader($et, $tagTablePtr, $word);
|
||||
|
||||
# extract the VBR information (ref MP3::Info)
|
||||
my ($v, $m) = ($$et{MPEG_Vers}, $$et{MPEG_Mode});
|
||||
while (defined $v and defined $m) {
|
||||
my $len = length $$buffPt;
|
||||
$pos += $v == 3 ? ($m == 3 ? 17 : 32) : ($m == 3 ? 9 : 17);
|
||||
last if $pos + 8 > $len;
|
||||
my $buff = substr($$buffPt, $pos, 8);
|
||||
last unless $buff =~ /^(Xing|Info)/;
|
||||
my $xingTable = GetTagTable('Image::ExifTool::MPEG::Xing');
|
||||
my $vbrScale;
|
||||
my $flags = unpack('x4N', $buff);
|
||||
my $isVBR = ($buff !~ /^Info/); # Info frame is not VBR (ref 5)
|
||||
$pos += 8;
|
||||
if ($flags & 0x01) { # VBRFrames
|
||||
last if $pos + 4 > $len;
|
||||
$et->HandleTag($xingTable, 1, unpack("x${pos}N", $$buffPt)) if $isVBR;
|
||||
$pos += 4;
|
||||
}
|
||||
if ($flags & 0x02) { # VBRBytes
|
||||
last if $pos + 4 > $len;
|
||||
$et->HandleTag($xingTable, 2, unpack("x${pos}N", $$buffPt)) if $isVBR;
|
||||
$pos += 4;
|
||||
}
|
||||
if ($flags & 0x04) { # VBR_TOC
|
||||
last if $pos + 100 > $len;
|
||||
# (ignore toc for now)
|
||||
$pos += 100;
|
||||
}
|
||||
if ($flags & 0x08) { # VBRScale
|
||||
last if $pos + 4 > $len;
|
||||
$vbrScale = unpack("x${pos}N", $$buffPt);
|
||||
$et->HandleTag($xingTable, 3, $vbrScale) if $isVBR;
|
||||
$pos += 4;
|
||||
}
|
||||
# process Lame header (ref 5)
|
||||
if ($flags & 0x10) { # Lame
|
||||
last if $pos + 348 > $len;
|
||||
} elsif ($pos + 4 <= $len) {
|
||||
my $lib = substr($$buffPt, $pos, 4);
|
||||
unless ($lib eq 'LAME' or $lib eq 'GOGO') {
|
||||
# attempt to identify other encoders
|
||||
my $n;
|
||||
if (index($$buffPt, 'RCA mp3PRO Encoder') >= 0) {
|
||||
$lib = 'RCA mp3PRO';
|
||||
} elsif (($n = index($$buffPt, 'THOMSON mp3PRO Encoder')) >= 0) {
|
||||
$lib = 'Thomson mp3PRO';
|
||||
$n += 22;
|
||||
$lib .= ' ' . substr($$buffPt, $n, 6) if length($$buffPt) - $n >= 6;
|
||||
} elsif (index($$buffPt, 'MPGE') >= 0) {
|
||||
$lib = 'Gogo (<3.0)';
|
||||
} else {
|
||||
last;
|
||||
}
|
||||
$et->HandleTag($xingTable, 4, $lib);
|
||||
last;
|
||||
}
|
||||
}
|
||||
my $lameLen = $len - $pos;
|
||||
last if $lameLen < 9;
|
||||
my $enc = substr($$buffPt, $pos, 9);
|
||||
if ($enc ge 'LAME3.90') {
|
||||
$et->HandleTag($xingTable, 4, $enc);
|
||||
if ($vbrScale <= 100) {
|
||||
$et->HandleTag($xingTable, 5, int((100 - $vbrScale) / 10));
|
||||
$et->HandleTag($xingTable, 6, (100 - $vbrScale) % 10);
|
||||
}
|
||||
my %dirInfo = (
|
||||
DataPt => $buffPt,
|
||||
DirStart => $pos,
|
||||
DirLen => length($$buffPt) - $pos,
|
||||
);
|
||||
my $subTablePtr = GetTagTable('Image::ExifTool::MPEG::Lame');
|
||||
$et->ProcessDirectory(\%dirInfo, $subTablePtr);
|
||||
} else {
|
||||
$et->HandleTag($xingTable, 4, substr($$buffPt, $pos, 20));
|
||||
}
|
||||
last; # (didn't want to loop anyway)
|
||||
}
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
#------------------------------------------------------------------------------
|
||||
# Read MPEG video frame header
|
||||
# Inputs: 0) ExifTool object reference, 1) Reference to video data
|
||||
# Returns: 1 on success, 0 if no video header was found
|
||||
sub ProcessMPEGVideo($$)
|
||||
{
|
||||
my ($et, $buffPt) = @_;
|
||||
|
||||
return 0 unless length $$buffPt >= 4;
|
||||
my ($w1, $w2) = unpack('N2', $$buffPt);
|
||||
# validate as much as possible
|
||||
if (($w1 & 0x000000f0) == 0x00000000 or # 0000 is a forbidden aspect ratio
|
||||
($w1 & 0x000000f0) == 0x000000f0 or # 1111 is a reserved aspect ratio
|
||||
($w1 & 0x0000000f) == 0 or # frame rate must be 1-8
|
||||
($w1 & 0x0000000f) > 8)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
# set file type if not done already
|
||||
$et->SetFileType('MPEG') unless $$et{VALUE}{FileType};
|
||||
|
||||
my $tagTablePtr = GetTagTable('Image::ExifTool::MPEG::Video');
|
||||
ProcessFrameHeader($et, $tagTablePtr, $w1, $w2);
|
||||
return 1;
|
||||
}
|
||||
|
||||
#------------------------------------------------------------------------------
|
||||
# Read MPEG audio and video frame headers
|
||||
# Inputs: 0) ExifTool object reference, 1) Reference to audio/video data
|
||||
# Returns: 1 on success, 0 if no video header was found
|
||||
# To Do: Properly parse MPEG streams:
|
||||
# 0xb7 - sequence end
|
||||
# 0xb9 - end code
|
||||
# 0xba - pack start code
|
||||
# 0xbb - system header
|
||||
# 0xbc - program map <-- should parse this
|
||||
# 0xbd - private stream 1 --> for VOB, this contains sub-streams:
|
||||
# 0x20-0x3f - pictures
|
||||
# 0x80-0x87 - audio (AC3,DTS,SDDS)
|
||||
# 0xa0-0xa7 - audio (LPCM)
|
||||
# 0xbe - padding
|
||||
# 0xbf - private stream 2
|
||||
# 0xc0-0xdf - audio stream
|
||||
# 0xe0-0xef - video stream
|
||||
sub ParseMPEGAudioVideo($$)
|
||||
{
|
||||
my ($et, $buffPt) = @_;
|
||||
my (%found, $didHdr);
|
||||
my $rtnVal = 0;
|
||||
my %proc = ( audio => \&ParseMPEGAudio, video => \&ProcessMPEGVideo );
|
||||
|
||||
delete $$et{AudioBitrate};
|
||||
delete $$et{VideoBitrate};
|
||||
|
||||
while ($$buffPt =~ /\0\0\x01(\xb3|\xc0)/g) {
|
||||
my $type = $1 eq "\xb3" ? 'video' : 'audio';
|
||||
unless ($didHdr) {
|
||||
# make sure we didn't miss an audio frame sync before this (eg. MP3 file)
|
||||
# (the last byte of the 4-byte MP3 audio frame header word may be zero,
|
||||
# but the 2nd last must be non-zero, so we need only check to pos-3)
|
||||
my $buff = substr($$buffPt, 0, pos($$buffPt) - 3);
|
||||
$found{audio} = 1 if ParseMPEGAudio($et, \$buff);
|
||||
$didHdr = 1;
|
||||
}
|
||||
next if $found{$type};
|
||||
my $len = length($$buffPt) - pos($$buffPt);
|
||||
last if $len < 4;
|
||||
$len > 256 and $len = 256;
|
||||
my $dat = substr($$buffPt, pos($$buffPt), $len);
|
||||
# process MPEG audio or video
|
||||
if (&{$proc{$type}}($et, \$dat)) {
|
||||
$rtnVal = 1;
|
||||
$found{$type} = 1;
|
||||
# done if we found audio and video
|
||||
last if scalar(keys %found) == 2;
|
||||
}
|
||||
}
|
||||
return $rtnVal;
|
||||
}
|
||||
|
||||
#------------------------------------------------------------------------------
|
||||
# Read information from an MPEG file
|
||||
# Inputs: 0) ExifTool object reference, 1) Directory information reference
|
||||
# Returns: 1 on success, 0 if this wasn't a valid MPEG file
|
||||
sub ProcessMPEG($$)
|
||||
{
|
||||
my ($et, $dirInfo) = @_;
|
||||
my $raf = $$dirInfo{RAF};
|
||||
my $buff;
|
||||
|
||||
$raf->Read($buff, 4) == 4 or return 0;
|
||||
return 0 unless $buff =~ /^\0\0\x01[\xb0-\xbf]/;
|
||||
$et->SetFileType();
|
||||
|
||||
$raf->Seek(0,0);
|
||||
$raf->Read($buff, 65536*4) or return 0;
|
||||
|
||||
return ParseMPEGAudioVideo($et, \$buff);
|
||||
}
|
||||
|
||||
1; # end
|
||||
|
||||
__END__
|
||||
|
||||
=head1 NAME
|
||||
|
||||
Image::ExifTool::MPEG - Read MPEG-1 and MPEG-2 meta information
|
||||
|
||||
=head1 SYNOPSIS
|
||||
|
||||
This module is used by Image::ExifTool
|
||||
|
||||
=head1 DESCRIPTION
|
||||
|
||||
This module contains definitions required by Image::ExifTool to read MPEG-1
|
||||
and MPEG-2 audio/video files.
|
||||
|
||||
=head1 NOTES
|
||||
|
||||
Since ISO charges money for the official MPEG specification, this module is
|
||||
based on unofficial sources which may be incomplete, inaccurate or outdated.
|
||||
|
||||
=head1 AUTHOR
|
||||
|
||||
Copyright 2003-2018, Phil Harvey (phil at owl.phy.queensu.ca)
|
||||
|
||||
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<http://www.mp3-tech.org/>
|
||||
|
||||
=item L<http://www.getid3.org/>
|
||||
|
||||
=item L<http://dvd.sourceforge.net/dvdinfo/dvdmpeg.html>
|
||||
|
||||
=item L<http://ffmpeg.org/>
|
||||
|
||||
=item L<http://sourceforge.net/projects/mediainfo/>
|
||||
|
||||
=back
|
||||
|
||||
=head1 SEE ALSO
|
||||
|
||||
L<Image::ExifTool::TagNames/MPEG Tags>,
|
||||
L<MP3::Info(3pm)|MP3::Info>,
|
||||
L<Image::ExifTool(3pm)|Image::ExifTool>
|
||||
|
||||
=cut
|
||||
|
||||
Reference in New Issue
Block a user