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+<?php
+
+/////////////////////////////////////////////////////////////////
+/// getID3() by James Heinrich <info@getid3.org> //
+// available at https://github.com/JamesHeinrich/getID3 //
+// or https://www.getid3.org //
+// or http://getid3.sourceforge.net //
+// see readme.txt for more details //
+/////////////////////////////////////////////////////////////////
+// //
+// module.archive.tiff.php //
+// module for analyzing TIFF files //
+// dependencies: NONE //
+// ///
+/////////////////////////////////////////////////////////////////
+
+if (!defined('GETID3_INCLUDEPATH')) { // prevent path-exposing attacks that access modules directly on public webservers
+ exit;
+}
+
+class getid3_tiff extends getid3_handler
+{
+ /**
+ * @return bool
+ */
+ public function Analyze() {
+ $info = &$this->getid3->info;
+
+ $this->fseek($info['avdataoffset']);
+ $TIFFheader = $this->fread(4);
+
+ switch (substr($TIFFheader, 0, 2)) {
+ case 'II':
+ $info['tiff']['byte_order'] = 'Intel';
+ break;
+ case 'MM':
+ $info['tiff']['byte_order'] = 'Motorola';
+ break;
+ default:
+ $this->error('Invalid TIFF byte order identifier ('.substr($TIFFheader, 0, 2).') at offset '.$info['avdataoffset']);
+ return false;
+ }
+
+ $info['fileformat'] = 'tiff';
+ $info['video']['dataformat'] = 'tiff';
+ $info['video']['lossless'] = true;
+ $info['tiff']['ifd'] = array();
+ $CurrentIFD = array();
+
+ $FieldTypeByteLength = array(1=>1, 2=>1, 3=>2, 4=>4, 5=>8);
+
+ $nextIFDoffset = $this->TIFFendian2Int($this->fread(4), $info['tiff']['byte_order']);
+
+ while ($nextIFDoffset > 0) {
+
+ $CurrentIFD['offset'] = $nextIFDoffset;
+
+ $this->fseek($info['avdataoffset'] + $nextIFDoffset);
+ $CurrentIFD['fieldcount'] = $this->TIFFendian2Int($this->fread(2), $info['tiff']['byte_order']);
+
+ for ($i = 0; $i < $CurrentIFD['fieldcount']; $i++) {
+ $CurrentIFD['fields'][$i]['raw']['tag'] = $this->TIFFendian2Int($this->fread(2), $info['tiff']['byte_order']);
+ $CurrentIFD['fields'][$i]['raw']['type'] = $this->TIFFendian2Int($this->fread(2), $info['tiff']['byte_order']);
+ $CurrentIFD['fields'][$i]['raw']['length'] = $this->TIFFendian2Int($this->fread(4), $info['tiff']['byte_order']);
+ $CurrentIFD['fields'][$i]['raw']['valoff'] = $this->fread(4); // To save time and space the Value Offset contains the Value instead of pointing to the Value if and only if the Value fits into 4 bytes. If the Value is shorter than 4 bytes, it is left-justified within the 4-byte Value Offset, i.e., stored in the lowernumbered bytes. Whether the Value fits within 4 bytes is determined by the Type and Count of the field.
+ $CurrentIFD['fields'][$i]['raw']['tag_name'] = $this->TIFFcommentName($CurrentIFD['fields'][$i]['raw']['tag']);
+
+ switch ($CurrentIFD['fields'][$i]['raw']['type']) {
+ case 1: // BYTE An 8-bit unsigned integer.
+ if ($CurrentIFD['fields'][$i]['raw']['length'] <= 4) {
+ $CurrentIFD['fields'][$i]['value'] = $this->TIFFendian2Int(substr($CurrentIFD['fields'][$i]['raw']['valoff'], 0, 1), $info['tiff']['byte_order']);
+ } else {
+ $CurrentIFD['fields'][$i]['offset'] = $this->TIFFendian2Int($CurrentIFD['fields'][$i]['raw']['valoff'], $info['tiff']['byte_order']);
+ }
+ break;
+
+ case 2: // ASCII 8-bit bytes that store ASCII codes; the last byte must be null.
+ if ($CurrentIFD['fields'][$i]['raw']['length'] <= 4) {
+ $CurrentIFD['fields'][$i]['value'] = substr($CurrentIFD['fields'][$i]['raw']['valoff'], 3);
+ } else {
+ $CurrentIFD['fields'][$i]['offset'] = $this->TIFFendian2Int($CurrentIFD['fields'][$i]['raw']['valoff'], $info['tiff']['byte_order']);
+ }
+ break;
+
+ case 3: // SHORT A 16-bit (2-byte) unsigned integer.
+ if ($CurrentIFD['fields'][$i]['raw']['length'] <= 2) {
+ $CurrentIFD['fields'][$i]['value'] = $this->TIFFendian2Int(substr($CurrentIFD['fields'][$i]['raw']['valoff'], 0, 2), $info['tiff']['byte_order']);
+ } else {
+ $CurrentIFD['fields'][$i]['offset'] = $this->TIFFendian2Int($CurrentIFD['fields'][$i]['raw']['valoff'], $info['tiff']['byte_order']);
+ }
+ break;
+
+ case 4: // LONG A 32-bit (4-byte) unsigned integer.
+ if ($CurrentIFD['fields'][$i]['raw']['length'] <= 4) {
+ $CurrentIFD['fields'][$i]['value'] = $this->TIFFendian2Int($CurrentIFD['fields'][$i]['raw']['valoff'], $info['tiff']['byte_order']);
+ } else {
+ $CurrentIFD['fields'][$i]['offset'] = $this->TIFFendian2Int($CurrentIFD['fields'][$i]['raw']['valoff'], $info['tiff']['byte_order']);
+ }
+ break;
+
+ case 5: // RATIONAL Two LONG_s: the first represents the numerator of a fraction, the second the denominator.
+ case 7: // UNDEFINED An 8-bit byte that may contain anything, depending on the definition of the field.
+ $CurrentIFD['fields'][$i]['offset'] = $this->TIFFendian2Int($CurrentIFD['fields'][$i]['raw']['valoff'], $info['tiff']['byte_order']);
+ break;
+
+ // Warning: It is possible that other TIFF field types will be added in the future. Readers should skip over fields containing an unexpected field type.
+ // In TIFF 6.0, some new field types have been defined:
+ // These new field types are also governed by the byte order (II or MM) in the TIFF header.
+ case 6: // SBYTE An 8-bit signed (twos-complement) integer.
+ case 8: // SSHORT A 16-bit (2-byte) signed (twos-complement) integer.
+ case 9: // SLONG A 32-bit (4-byte) signed (twos-complement) integer.
+ case 10: // SRATIONAL Two SLONGs: the first represents the numerator of a fraction, the second the denominator.
+ case 11: // FLOAT Single precision (4-byte) IEEE format
+ case 12: // DOUBLE Double precision (8-byte) IEEE format
+ default:
+ $this->warning('unhandled IFD field type '.$CurrentIFD['fields'][$i]['raw']['type'].' for IFD entry '.$i);
+ break;
+ }
+ }
+
+ $info['tiff']['ifd'][] = $CurrentIFD;
+ $CurrentIFD = array();
+ $nextIFDoffset = $this->TIFFendian2Int($this->fread(4), $info['tiff']['byte_order']);
+
+ }
+
+ foreach ($info['tiff']['ifd'] as $IFDid => $IFDarray) {
+ foreach ($IFDarray['fields'] as $key => $fieldarray) {
+ switch ($fieldarray['raw']['tag']) {
+ case 256: // ImageWidth
+ case 257: // ImageLength
+ case 258: // BitsPerSample
+ case 259: // Compression
+ if (!isset($fieldarray['value'])) {
+ $this->fseek($fieldarray['offset']);
+ $info['tiff']['ifd'][$IFDid]['fields'][$key]['raw']['data'] = $this->fread($fieldarray['raw']['length'] * $FieldTypeByteLength[$fieldarray['raw']['type']]);
+
+ }
+ break;
+
+ case 270: // ImageDescription
+ case 271: // Make
+ case 272: // Model
+ case 305: // Software
+ case 306: // DateTime
+ case 315: // Artist
+ case 316: // HostComputer
+ if (isset($fieldarray['value'])) {
+ $info['tiff']['ifd'][$IFDid]['fields'][$key]['raw']['data'] = $fieldarray['value'];
+ } else {
+ $this->fseek($fieldarray['offset']);
+ $info['tiff']['ifd'][$IFDid]['fields'][$key]['raw']['data'] = $this->fread($fieldarray['raw']['length'] * $FieldTypeByteLength[$fieldarray['raw']['type']]);
+
+ }
+ break;
+ case 700:
+ $XMPmagic = '<?xpacket';
+ $this->fseek($fieldarray['offset']);
+ $xmpkey = (isset($info['tiff']['XMP']) ? count($info['tiff']['XMP']) : 0);
+ $info['tiff']['XMP'][$xmpkey]['raw'] = $this->fread($fieldarray['raw']['length']);
+ if (substr($info['tiff']['XMP'][$xmpkey]['raw'], 0, strlen($XMPmagic)) != $XMPmagic) {
+ $this->warning('did not find expected XMP data at offset '.$fieldarray['offset']);
+ unset($info['tiff']['XMP'][$xmpkey]['raw']);
+ }
+ break;
+ }
+ switch ($fieldarray['raw']['tag']) {
+ case 256: // ImageWidth
+ $info['video']['resolution_x'] = $fieldarray['value'];
+ break;
+
+ case 257: // ImageLength
+ $info['video']['resolution_y'] = $fieldarray['value'];
+ break;
+
+ case 258: // BitsPerSample
+ if (isset($fieldarray['value'])) {
+ $info['video']['bits_per_sample'] = $fieldarray['value'];
+ } else {
+ $info['video']['bits_per_sample'] = 0;
+ for ($i = 0; $i < $fieldarray['raw']['length']; $i++) {
+ $info['video']['bits_per_sample'] += $this->TIFFendian2Int(substr($info['tiff']['ifd'][$IFDid]['fields'][$key]['raw']['data'], $i * $FieldTypeByteLength[$fieldarray['raw']['type']], $FieldTypeByteLength[$fieldarray['raw']['type']]), $info['tiff']['byte_order']);
+ }
+ }
+ break;
+
+ case 259: // Compression
+ $info['video']['codec'] = $this->TIFFcompressionMethod($fieldarray['value']);
+ break;
+
+ case 270: // ImageDescription
+ case 271: // Make
+ case 272: // Model
+ case 305: // Software
+ case 306: // DateTime
+ case 315: // Artist
+ case 316: // HostComputer
+ $TIFFcommentName = strtolower($fieldarray['raw']['tag_name']);
+ if (isset($info['tiff']['comments'][$TIFFcommentName])) {
+ $info['tiff']['comments'][$TIFFcommentName][] = $info['tiff']['ifd'][$IFDid]['fields'][$key]['raw']['data'];
+ } else {
+ $info['tiff']['comments'][$TIFFcommentName] = array($info['tiff']['ifd'][$IFDid]['fields'][$key]['raw']['data']);
+ }
+ break;
+
+ default:
+ break;
+ }
+ }
+ }
+
+ return true;
+ }
+
+ /**
+ * @param string $bytestring
+ * @param string $byteorder
+ *
+ * @return int|float|false
+ */
+ public function TIFFendian2Int($bytestring, $byteorder) {
+ if ($byteorder == 'Intel') {
+ return getid3_lib::LittleEndian2Int($bytestring);
+ } elseif ($byteorder == 'Motorola') {
+ return getid3_lib::BigEndian2Int($bytestring);
+ }
+ return false;
+ }
+
+ /**
+ * @param int $id
+ *
+ * @return string
+ */
+ public function TIFFcompressionMethod($id) {
+ // https://en.wikipedia.org/wiki/TIFF#TIFF_Compression_Tag
+ static $TIFFcompressionMethod = array();
+ if (empty($TIFFcompressionMethod)) {
+ $TIFFcompressionMethod = array(
+ 0x0001 => 'Uncompressed',
+ 0x0002 => 'Huffman',
+ 0x0003 => 'CCITT T.4',
+ 0x0004 => 'CCITT T.6',
+ 0x0005 => 'LZW',
+ 0x0006 => 'JPEG-old',
+ 0x0007 => 'JPEG',
+ 0x0008 => 'deflate',
+ 0x0009 => 'JBIG ITU-T T.85',
+ 0x000A => 'JBIG ITU-T T.43',
+ 0x7FFE => 'NeXT RLE 2-bit',
+ 0x8005 => 'PackBits',
+ 0x8029 => 'ThunderScan RLE 4-bit',
+ 0x807F => 'RasterPadding',
+ 0x8080 => 'RLE-LW',
+ 0x8081 => 'RLE-CT',
+ 0x8082 => 'RLE-BL',
+ 0x80B2 => 'deflate-PK',
+ 0x80B3 => 'Kodak-DCS',
+ 0x8765 => 'JBIG',
+ 0x8798 => 'JPEG2000',
+ 0x8799 => 'Nikon NEF',
+ 0x879B => 'JBIG2',
+ );
+ }
+ return (isset($TIFFcompressionMethod[$id]) ? $TIFFcompressionMethod[$id] : 'unknown/invalid ('.$id.')');
+ }
+
+ /**
+ * @param int $id
+ *
+ * @return string
+ */
+ public function TIFFcommentName($id) {
+ // https://www.awaresystems.be/imaging/tiff/tifftags.html
+ static $TIFFcommentName = array();
+ if (empty($TIFFcommentName)) {
+ $TIFFcommentName = array(
+ 254 => 'NewSubfileType',
+ 255 => 'SubfileType',
+ 256 => 'ImageWidth',
+ 257 => 'ImageLength',
+ 258 => 'BitsPerSample',
+ 259 => 'Compression',
+ 262 => 'PhotometricInterpretation',
+ 263 => 'Threshholding',
+ 264 => 'CellWidth',
+ 265 => 'CellLength',
+ 266 => 'FillOrder',
+ 269 => 'DocumentName',
+ 270 => 'ImageDescription',
+ 271 => 'Make',
+ 272 => 'Model',
+ 273 => 'StripOffsets',
+ 274 => 'Orientation',
+ 277 => 'SamplesPerPixel',
+ 278 => 'RowsPerStrip',
+ 279 => 'StripByteCounts',
+ 280 => 'MinSampleValue',
+ 281 => 'MaxSampleValue',
+ 282 => 'XResolution',
+ 283 => 'YResolution',
+ 284 => 'PlanarConfiguration',
+ 285 => 'PageName',
+ 286 => 'XPosition',
+ 287 => 'YPosition',
+ 288 => 'FreeOffsets',
+ 289 => 'FreeByteCounts',
+ 290 => 'GrayResponseUnit',
+ 291 => 'GrayResponseCurve',
+ 292 => 'T4Options',
+ 293 => 'T6Options',
+ 296 => 'ResolutionUnit',
+ 297 => 'PageNumber',
+ 301 => 'TransferFunction',
+ 305 => 'Software',
+ 306 => 'DateTime',
+ 315 => 'Artist',
+ 316 => 'HostComputer',
+ 317 => 'Predictor',
+ 318 => 'WhitePoint',
+ 319 => 'PrimaryChromaticities',
+ 320 => 'ColorMap',
+ 321 => 'HalftoneHints',
+ 322 => 'TileWidth',
+ 323 => 'TileLength',
+ 324 => 'TileOffsets',
+ 325 => 'TileByteCounts',
+ 326 => 'BadFaxLines',
+ 327 => 'CleanFaxData',
+ 328 => 'ConsecutiveBadFaxLines',
+ 330 => 'SubIFDs',
+ 332 => 'InkSet',
+ 333 => 'InkNames',
+ 334 => 'NumberOfInks',
+ 336 => 'DotRange',
+ 337 => 'TargetPrinter',
+ 338 => 'ExtraSamples',
+ 339 => 'SampleFormat',
+ 340 => 'SMinSampleValue',
+ 341 => 'SMaxSampleValue',
+ 342 => 'TransferRange',
+ 343 => 'ClipPath',
+ 344 => 'XClipPathUnits',
+ 345 => 'YClipPathUnits',
+ 346 => 'Indexed',
+ 347 => 'JPEGTables',
+ 351 => 'OPIProxy',
+ 400 => 'GlobalParametersIFD',
+ 401 => 'ProfileType',
+ 402 => 'FaxProfile',
+ 403 => 'CodingMethods',
+ 404 => 'VersionYear',
+ 405 => 'ModeNumber',
+ 433 => 'Decode',
+ 434 => 'DefaultImageColor',
+ 512 => 'JPEGProc',
+ 513 => 'JPEGInterchangeFormat',
+ 514 => 'JPEGInterchangeFormatLngth',
+ 515 => 'JPEGRestartInterval',
+ 517 => 'JPEGLosslessPredictors',
+ 518 => 'JPEGPointTransforms',
+ 519 => 'JPEGQTables',
+ 520 => 'JPEGDCTables',
+ 521 => 'JPEGACTables',
+ 529 => 'YCbCrCoefficients',
+ 530 => 'YCbCrSubSampling',
+ 531 => 'YCbCrPositioning',
+ 532 => 'ReferenceBlackWhite',
+ 559 => 'StripRowCounts',
+ 700 => 'XMP',
+
+ 32781 => 'ImageID',
+ 33432 => 'Copyright',
+ 34732 => 'ImageLayer',
+
+ // Private Tags - https://www.awaresystems.be/imaging/tiff/tifftags/private.html
+ 32932 => 'Wang Annotation', // Annotation data, as used in 'Imaging for Windows'.
+ 33445 => 'MD FileTag', // Specifies the pixel data format encoding in the Molecular Dynamics GEL file format.
+ 33446 => 'MD ScalePixel', // Specifies a scale factor in the Molecular Dynamics GEL file format.
+ 33447 => 'MD ColorTable', // Used to specify the conversion from 16bit to 8bit in the Molecular Dynamics GEL file format.
+ 33448 => 'MD LabName', // Name of the lab that scanned this file, as used in the Molecular Dynamics GEL file format.
+ 33449 => 'MD SampleInfo', // Information about the sample, as used in the Molecular Dynamics GEL file format.
+ 33450 => 'MD PrepDate', // Date the sample was prepared, as used in the Molecular Dynamics GEL file format.
+ 33451 => 'MD PrepTime', // Time the sample was prepared, as used in the Molecular Dynamics GEL file format.
+ 33452 => 'MD FileUnits', // Units for data in this file, as used in the Molecular Dynamics GEL file format.
+ 33550 => 'ModelPixelScaleTag', // Used in interchangeable GeoTIFF files.
+ 33723 => 'IPTC', // IPTC (International Press Telecommunications Council) metadata.
+ 33918 => 'INGR Packet Data Tag', // Intergraph Application specific storage.
+ 33919 => 'INGR Flag Registers', // Intergraph Application specific flags.
+ 33920 => 'IrasB Transformation Matrix', // Originally part of Intergraph's GeoTIFF tags, but likely understood by IrasB only.
+ 33922 => 'ModelTiepointTag', // Originally part of Intergraph's GeoTIFF tags, but now used in interchangeable GeoTIFF files.
+ 34264 => 'ModelTransformationTag', // Used in interchangeable GeoTIFF files.
+ 34377 => 'Photoshop', // Collection of Photoshop 'Image Resource Blocks'.
+ 34665 => 'Exif IFD', // A pointer to the Exif IFD.
+ 34675 => 'ICC Profile', // ICC profile data.
+ 34735 => 'GeoKeyDirectoryTag', // Used in interchangeable GeoTIFF files.
+ 34736 => 'GeoDoubleParamsTag', // Used in interchangeable GeoTIFF files.
+ 34737 => 'GeoAsciiParamsTag', // Used in interchangeable GeoTIFF files.
+ 34853 => 'GPS IFD', // A pointer to the Exif-related GPS Info IFD.
+ 34908 => 'HylaFAX FaxRecvParams', // Used by HylaFAX.
+ 34909 => 'HylaFAX FaxSubAddress', // Used by HylaFAX.
+ 34910 => 'HylaFAX FaxRecvTime', // Used by HylaFAX.
+ 37724 => 'ImageSourceData', // Used by Adobe Photoshop.
+ 40965 => 'Interoperability IFD', // A pointer to the Exif-related Interoperability IFD.
+ 42112 => 'GDAL_METADATA', // Used by the GDAL library, holds an XML list of name=value 'metadata' values about the image as a whole, and about specific samples.
+ 42113 => 'GDAL_NODATA', // Used by the GDAL library, contains an ASCII encoded nodata or background pixel value.
+ 50215 => 'Oce Scanjob Description', // Used in the Oce scanning process.
+ 50216 => 'Oce Application Selector', // Used in the Oce scanning process.
+ 50217 => 'Oce Identification Number', // Used in the Oce scanning process.
+ 50218 => 'Oce ImageLogic Characteristics', // Used in the Oce scanning process.
+ 50706 => 'DNGVersion', // Used in IFD 0 of DNG files.
+ 50707 => 'DNGBackwardVersion', // Used in IFD 0 of DNG files.
+ 50708 => 'UniqueCameraModel', // Used in IFD 0 of DNG files.
+ 50709 => 'LocalizedCameraModel', // Used in IFD 0 of DNG files.
+ 50710 => 'CFAPlaneColor', // Used in Raw IFD of DNG files.
+ 50711 => 'CFALayout', // Used in Raw IFD of DNG files.
+ 50712 => 'LinearizationTable', // Used in Raw IFD of DNG files.
+ 50713 => 'BlackLevelRepeatDim', // Used in Raw IFD of DNG files.
+ 50714 => 'BlackLevel', // Used in Raw IFD of DNG files.
+ 50715 => 'BlackLevelDeltaH', // Used in Raw IFD of DNG files.
+ 50716 => 'BlackLevelDeltaV', // Used in Raw IFD of DNG files.
+ 50717 => 'WhiteLevel', // Used in Raw IFD of DNG files.
+ 50718 => 'DefaultScale', // Used in Raw IFD of DNG files.
+ 50719 => 'DefaultCropOrigin', // Used in Raw IFD of DNG files.
+ 50720 => 'DefaultCropSize', // Used in Raw IFD of DNG files.
+ 50721 => 'ColorMatrix1', // Used in IFD 0 of DNG files.
+ 50722 => 'ColorMatrix2', // Used in IFD 0 of DNG files.
+ 50723 => 'CameraCalibration1', // Used in IFD 0 of DNG files.
+ 50724 => 'CameraCalibration2', // Used in IFD 0 of DNG files.
+ 50725 => 'ReductionMatrix1', // Used in IFD 0 of DNG files.
+ 50726 => 'ReductionMatrix2', // Used in IFD 0 of DNG files.
+ 50727 => 'AnalogBalance', // Used in IFD 0 of DNG files.
+ 50728 => 'AsShotNeutral', // Used in IFD 0 of DNG files.
+ 50729 => 'AsShotWhiteXY', // Used in IFD 0 of DNG files.
+ 50730 => 'BaselineExposure', // Used in IFD 0 of DNG files.
+ 50731 => 'BaselineNoise', // Used in IFD 0 of DNG files.
+ 50732 => 'BaselineSharpness', // Used in IFD 0 of DNG files.
+ 50733 => 'BayerGreenSplit', // Used in Raw IFD of DNG files.
+ 50734 => 'LinearResponseLimit', // Used in IFD 0 of DNG files.
+ 50735 => 'CameraSerialNumber', // Used in IFD 0 of DNG files.
+ 50736 => 'LensInfo', // Used in IFD 0 of DNG files.
+ 50737 => 'ChromaBlurRadius', // Used in Raw IFD of DNG files.
+ 50738 => 'AntiAliasStrength', // Used in Raw IFD of DNG files.
+ 50740 => 'DNGPrivateData', // Used in IFD 0 of DNG files.
+ 50741 => 'MakerNoteSafety', // Used in IFD 0 of DNG files.
+ 50778 => 'CalibrationIlluminant1', // Used in IFD 0 of DNG files.
+ 50779 => 'CalibrationIlluminant2', // Used in IFD 0 of DNG files.
+ 50780 => 'BestQualityScale', // Used in Raw IFD of DNG files.
+ 50784 => 'Alias Layer Metadata', // Alias Sketchbook Pro layer usage description.
+ 50908 => 'TIFF_RSID', // This private tag is used in a GEOTIFF standard by DGIWG.
+ 50909 => 'GEO_METADATA', // This private tag is used in a GEOTIFF standard by DGIWG.
+
+ // EXIF tags - https://www.awaresystems.be/imaging/tiff/tifftags/privateifd/exif.html
+ 33434 => 'ExposureTime', // Exposure time, given in seconds.
+ 33437 => 'FNumber', // The F number.
+ 34850 => 'ExposureProgram', // The class of the program used by the camera to set exposure when the picture is taken.
+ 34852 => 'SpectralSensitivity', // Indicates the spectral sensitivity of each channel of the camera used.
+ 34855 => 'ISOSpeedRatings', // Indicates the ISO Speed and ISO Latitude of the camera or input device as specified in ISO 12232.
+ 34856 => 'OECF', // Indicates the Opto-Electric Conversion Function (OECF) specified in ISO 14524.
+ 36864 => 'ExifVersion', // The version of the supported Exif standard.
+ 36867 => 'DateTimeOriginal', // The date and time when the original image data was generated.
+ 36868 => 'DateTimeDigitized', // The date and time when the image was stored as digital data.
+ 37121 => 'ComponentsConfiguration', // Specific to compressed data; specifies the channels and complements PhotometricInterpretation
+ 37122 => 'CompressedBitsPerPixel', // Specific to compressed data; states the compressed bits per pixel.
+ 37377 => 'ShutterSpeedValue', // Shutter speed.
+ 37378 => 'ApertureValue', // The lens aperture.
+ 37379 => 'BrightnessValue', // The value of brightness.
+ 37380 => 'ExposureBiasValue', // The exposure bias.
+ 37381 => 'MaxApertureValue', // The smallest F number of the lens.
+ 37382 => 'SubjectDistance', // The distance to the subject, given in meters.
+ 37383 => 'MeteringMode', // The metering mode.
+ 37384 => 'LightSource', // The kind of light source.
+ 37385 => 'Flash', // Indicates the status of flash when the image was shot.
+ 37386 => 'FocalLength', // The actual focal length of the lens, in mm.
+ 37396 => 'SubjectArea', // Indicates the location and area of the main subject in the overall scene.
+ 37500 => 'MakerNote', // Manufacturer specific information.
+ 37510 => 'UserComment', // Keywords or comments on the image; complements ImageDescription.
+ 37520 => 'SubsecTime', // A tag used to record fractions of seconds for the DateTime tag.
+ 37521 => 'SubsecTimeOriginal', // A tag used to record fractions of seconds for the DateTimeOriginal tag.
+ 37522 => 'SubsecTimeDigitized', // A tag used to record fractions of seconds for the DateTimeDigitized tag.
+ 40960 => 'FlashpixVersion', // The Flashpix format version supported by a FPXR file.
+ 40961 => 'ColorSpace', // The color space information tag is always recorded as the color space specifier.
+ 40962 => 'PixelXDimension', // Specific to compressed data; the valid width of the meaningful image.
+ 40963 => 'PixelYDimension', // Specific to compressed data; the valid height of the meaningful image.
+ 40964 => 'RelatedSoundFile', // Used to record the name of an audio file related to the image data.
+ 41483 => 'FlashEnergy', // Indicates the strobe energy at the time the image is captured, as measured in Beam Candle Power Seconds
+ 41484 => 'SpatialFrequencyResponse', // Records the camera or input device spatial frequency table and SFR values in the direction of image width, image height, and diagonal direction, as specified in ISO 12233.
+ 41486 => 'FocalPlaneXResolution', // Indicates the number of pixels in the image width (X) direction per FocalPlaneResolutionUnit on the camera focal plane.
+ 41487 => 'FocalPlaneYResolution', // Indicates the number of pixels in the image height (Y) direction per FocalPlaneResolutionUnit on the camera focal plane.
+ 41488 => 'FocalPlaneResolutionUnit', // Indicates the unit for measuring FocalPlaneXResolution and FocalPlaneYResolution.
+ 41492 => 'SubjectLocation', // Indicates the location of the main subject in the scene.
+ 41493 => 'ExposureIndex', // Indicates the exposure index selected on the camera or input device at the time the image is captured.
+ 41495 => 'SensingMethod', // Indicates the image sensor type on the camera or input device.
+ 41728 => 'FileSource', // Indicates the image source.
+ 41729 => 'SceneType', // Indicates the type of scene.
+ 41730 => 'CFAPattern', // Indicates the color filter array (CFA) geometric pattern of the image sensor when a one-chip color area sensor is used.
+ 41985 => 'CustomRendered', // Indicates the use of special processing on image data, such as rendering geared to output.
+ 41986 => 'ExposureMode', // Indicates the exposure mode set when the image was shot.
+ 41987 => 'WhiteBalance', // Indicates the white balance mode set when the image was shot.
+ 41988 => 'DigitalZoomRatio', // Indicates the digital zoom ratio when the image was shot.
+ 41989 => 'FocalLengthIn35mmFilm', // Indicates the equivalent focal length assuming a 35mm film camera, in mm.
+ 41990 => 'SceneCaptureType', // Indicates the type of scene that was shot.
+ 41991 => 'GainControl', // Indicates the degree of overall image gain adjustment.
+ 41992 => 'Contrast', // Indicates the direction of contrast processing applied by the camera when the image was shot.
+ 41993 => 'Saturation', // Indicates the direction of saturation processing applied by the camera when the image was shot.
+ 41994 => 'Sharpness', // Indicates the direction of sharpness processing applied by the camera when the image was shot.
+ 41995 => 'DeviceSettingDescription', // This tag indicates information on the picture-taking conditions of a particular camera model.
+ 41996 => 'SubjectDistanceRange', // Indicates the distance to the subject.
+ 42016 => 'ImageUniqueID', // Indicates an identifier assigned uniquely to each image.
+ );
+ }
+ return (isset($TIFFcommentName[$id]) ? $TIFFcommentName[$id] : 'unknown/invalid ('.$id.')');
+ }
+
+
+}