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Diffstat (limited to 'includes/jpeg_metadata_tk/EXIF.php')
| -rw-r--r-- | includes/jpeg_metadata_tk/EXIF.php | 2764 |
1 files changed, 2764 insertions, 0 deletions
diff --git a/includes/jpeg_metadata_tk/EXIF.php b/includes/jpeg_metadata_tk/EXIF.php new file mode 100644 index 0000000..8751dcd --- /dev/null +++ b/includes/jpeg_metadata_tk/EXIF.php @@ -0,0 +1,2764 @@ +<? + +/****************************************************************************** +* +* Filename: EXIF.php +* +* Description: Provides functions for reading and writing EXIF Information +* to/from an APP1 segment of a JPEG file +* Unfortunately, because EXIF data may be distributed anywhere +* throughout an image file, rather than just being in one block, +* it is impossible to pass just a string containing only the EXIF +* information. Hence it is neccessary to be able to seek to +* any point in the file. This causes the HTTP and FTP wrappers +* not to work - i.e. the EXIF functions will only work with local +* files. +* To work on an internet file, copy it locally to start with: +* +* $newfilename = tempnam ( $dir, "tmpexif" ); +* copy ( "http://whatever.com", $newfilename ); +* +* +* Author: Evan Hunter +* +* Date: 30/7/2004 +* +* Project: PHP JPEG Metadata Toolkit +* +* Revision: 1.11 +* +* Changes: 1.00 -> 1.10 : added function get_EXIF_TIFF to allow extracting EXIF from a TIFF file +* 1.10 -> 1.11 : added functionality to allow decoding of XMP and Photoshop IRB information +* embedded within the EXIF data +* added checks for http and ftp wrappers, as these are not supported +* changed interpret_IFD to allow thumbnail links to work when +* toolkit is portable across directories +* +* +* URL: http://electronics.ozhiker.com +* +* Copyright: Copyright Evan Hunter 2004 +* +* License: This file is part of the PHP JPEG Metadata Toolkit. +* +* The PHP JPEG Metadata Toolkit is free software; you can +* redistribute it and/or modify it under the terms of the +* GNU General Public License as published by the Free Software +* Foundation; either version 2 of the License, or (at your +* option) any later version. +* +* The PHP JPEG Metadata Toolkit is distributed in the hope +* that it will be useful, but WITHOUT ANY WARRANTY; without +* even the implied warranty of MERCHANTABILITY or FITNESS +* FOR A PARTICULAR PURPOSE. See the GNU General Public License +* for more details. +* +* You should have received a copy of the GNU General Public +* License along with the PHP JPEG Metadata Toolkit; if not, +* write to the Free Software Foundation, Inc., 59 Temple +* Place, Suite 330, Boston, MA 02111-1307 USA +* +* If you require a different license for commercial or other +* purposes, please contact the author: evan@ozhiker.com +* +******************************************************************************/ + + +// TODO : Thoroughly test the functions for writing EXIF segments +// TODO : Figure out a way to allow EXIF to function normally with HTTP and FTP wrappers +// TODO : Implement EXIF decoding of Device Setting Description field +// TODO : Implement EXIF decoding of SpatialFrequencyResponse field +// TODO : Implement EXIF decoding of OECF field +// TODO : Implement EXIF decoding of SubjectArea field +// TODO : Add a put_EXIF_TIFF function + +/****************************************************************************** +* +* Initialisation +* +******************************************************************************/ + + +if ( !isset( $GLOBALS['HIDE_UNKNOWN_TAGS'] ) ) $GLOBALS['HIDE_UNKNOWN_TAGS']= FALSE; +if ( !isset( $GLOBALS['SHOW_BINARY_DATA_HEX'] ) ) $GLOBALS['SHOW_BINARY_DATA_HEX'] = FALSE; +if ( !isset( $GLOBALS['SHOW_BINARY_DATA_TEXT'] ) ) $GLOBALS['SHOW_BINARY_DATA_TEXT'] = FALSE; + + +include_once 'EXIF_Tags.php'; +include_once 'EXIF_Makernote.php'; +include_once 'PIM.php'; +include_once 'Unicode.php'; +include_once 'JPEG.php'; +include_once 'IPTC.php'; +include_once 'Photoshop_IRB.php'; // Change: as of version 1.11 - Required for TIFF with embedded IRB +include_once 'XMP.php'; // Change: as of version 1.11 - Required for TIFF with embedded XMP +include_once 'pjmt_utils.php'; // Change: as of version 1.11 - Required for directory portability + + + + + + + + +/****************************************************************************** +* +* Function: get_EXIF_JPEG +* +* Description: Retrieves information from a Exchangeable Image File Format (EXIF) +* APP1 segment and returns it in an array. +* +* Parameters: filename - the filename of the JPEG image to process +* +* Returns: OutputArray - Array of EXIF records +* FALSE - If an error occured in decoding +* +******************************************************************************/ + +function get_EXIF_JPEG( $filename ) +{ + // Change: Added as of version 1.11 + // Check if a wrapper is being used - these are not currently supported (see notes at top of file) + if ( ( stristr ( $filename, "http://" ) != FALSE ) || ( stristr ( $filename, "ftp://" ) != FALSE ) ) + { + // A HTTP or FTP wrapper is being used - show a warning and abort + error_log( "HTTP and FTP wrappers are currently not supported with EXIF - See EXIF functionality documentation - a local file must be specified<br> + To work on an internet file, copy it locally to start with:<br><br>\n + $newfilename = tempnam ( \$dir, \"tmpexif\" );<br>\n + copy ( \"http://whatever.com\", \$newfilename );<br><br>\n" ); + return FALSE; + } + + // get the JPEG headers + $jpeg_header_data = get_jpeg_header_data( $filename ); + + + // Flag that an EXIF segment has not been found yet + $EXIF_Location = -1; + + //Cycle through the header segments + for( $i = 0; $i < count( $jpeg_header_data ); $i++ ) + { + // If we find an APP1 header, + if ( strcmp ( $jpeg_header_data[$i]['SegName'], "APP1" ) == 0 ) + { + // And if it has the EXIF label, + if ( ( strncmp ( $jpeg_header_data[$i]['SegData'], "Exif\x00\x00", 6) == 0 ) || + ( strncmp ( $jpeg_header_data[$i]['SegData'], "Exif\x00\xFF", 6) == 0 ) ) // For some reason, some files have a faulty EXIF name which has a 0xFF in it + { + // Save the location of the EXIF segment + $EXIF_Location = $i; + } + } + + } + + // Check if an EXIF segment was found + if ( $EXIF_Location == -1 ) + { + // Couldn't find any EXIF block to decode + return FALSE; + } + + $filehnd = @fopen($filename, 'rb'); + + // Check if the file opened successfully + if ( ! $filehnd ) + { + // Could't open the file - exit + error_log( "Could not open file $filename" ); + return FALSE; + } + + fseek( $filehnd, $jpeg_header_data[$EXIF_Location]['SegDataStart'] + 6 ); + + // Decode the Exif segment into an array and return it + $exif_data = process_TIFF_Header( $filehnd, "TIFF" ); + + + + // Close File + fclose($filehnd); + return $exif_data; +} + +/****************************************************************************** +* End of Function: get_EXIF_JPEG +******************************************************************************/ + + + +/****************************************************************************** +* +* Function: put_EXIF_JPEG +* +* Description: Stores information into a Exchangeable Image File Format (EXIF) +* APP1 segment from an EXIF array. +* +* WARNING: Because the EXIF standard allows pointers to data +* outside the APP1 segment, if there are any such pointers in +* a makernote, this function will DAMAGE them since it will not +* be aware that there is an external pointer. This will often +* happen with Makernotes that include an embedded thumbnail. +* This damage could be prevented where makernotes can be decoded, +* but currently this is not implemented. +* +* +* Parameters: exif_data - The array of EXIF data to insert into the JPEG header +* jpeg_header_data - The JPEG header into which the EXIF data +* should be stored, as from get_jpeg_header_data +* +* Returns: jpeg_header_data - JPEG header array with the EXIF segment inserted +* FALSE - If an error occured +* +******************************************************************************/ + +function put_EXIF_JPEG( $exif_data, $jpeg_header_data ) +{ + // pack the EXIF data into its proper format for a JPEG file + $packed_data = get_TIFF_Packed_Data( $exif_data ); + if ( $packed_data === FALSE ) + { + return $jpeg_header_data; + } + + $packed_data = "Exif\x00\x00$packed_data"; + + //Cycle through the header segments + for( $i = 0; $i < count( $jpeg_header_data ); $i++ ) + { + // If we find an APP1 header, + if ( strcmp ( $jpeg_header_data[$i]['SegName'], "APP1" ) == 0 ) + { + // And if it has the EXIF label, + if ( ( strncmp ( $jpeg_header_data[$i]['SegData'], "Exif\x00\x00", 6) == 0 ) || + ( strncmp ( $jpeg_header_data[$i]['SegData'], "Exif\x00\xFF", 6) == 0 ) ) // For some reason, some files have a faulty EXIF name which has a 0xFF in it + { + // Found a preexisting EXIF block - Replace it with the new one and return. + $jpeg_header_data[$i]['SegData'] = $packed_data; + return $jpeg_header_data; + } + } + } + + // No preexisting segment segment found, insert a new one at the start of the header data. + + // Determine highest position of an APP segment at or below APP3, so we can put the + // new APP3 at this position + + + $highest_APP = -1; + + //Cycle through the header segments + for( $i = 0; $i < count( $jpeg_header_data ); $i++ ) + { + // Check if we have found an APP segment at or below APP3, + if ( ( $jpeg_header_data[$i]['SegType'] >= 0xE0 ) && ( $jpeg_header_data[$i]['SegType'] <= 0xE3 ) ) + { + // Found an APP segment at or below APP12 + $highest_APP = $i; + } + } + + // No preexisting EXIF block found, insert a new one at the start of the header data. + array_splice($jpeg_header_data, $highest_APP + 1 , 0, array( array( "SegType" => 0xE1, + "SegName" => "APP1", + "SegDesc" => $GLOBALS[ "JPEG_Segment_Descriptions" ][ 0xE1 ], + "SegData" => $packed_data ) ) ); + return $jpeg_header_data; + +} + +/****************************************************************************** +* End of Function: put_EXIF_JPEG +******************************************************************************/ + + + + +/****************************************************************************** +* +* Function: get_Meta_JPEG +* +* Description: Retrieves information from a Meta APP3 segment and returns it +* in an array. Uses information supplied by the +* get_jpeg_header_data function. +* The Meta segment has the same format as an EXIF segment, but +* uses different tags +* +* Parameters: filename - the filename of the JPEG image to process +* +* Returns: OutputArray - Array of Meta records +* FALSE - If an error occured in decoding +* +******************************************************************************/ + +function get_Meta_JPEG( $filename ) +{ + // Change: Added as of version 1.11 + // Check if a wrapper is being used - these are not currently supported (see notes at top of file) + if ( ( stristr ( $filename, "http://" ) != FALSE ) || ( stristr ( $filename, "ftp://" ) != FALSE ) ) + { + // A HTTP or FTP wrapper is being used - show a warning and abort + echo "HTTP and FTP wrappers are currently not supported with Meta - See EXIF/Meta functionality documentation - a local file must be specified<br>"; + echo "To work on an internet file, copy it locally to start with:<br><br>\n"; + echo "\$newfilename = tempnam ( \$dir, \"tmpmeta\" );<br>\n"; + echo "copy ( \"http://whatever.com\", \$newfilename );<br><br>\n"; + return FALSE; + } + + // get the JPEG headers + $jpeg_header_data = get_jpeg_header_data( $filename ); + + + // Flag that an Meta segment has not been found yet + $Meta_Location = -1; + + //Cycle through the header segments + for( $i = 0; $i < count( $jpeg_header_data ); $i++ ) + { + // If we find an APP3 header, + if ( strcmp ( $jpeg_header_data[$i]['SegName'], "APP3" ) == 0 ) + { + // And if it has the Meta label, + if ( ( strncmp ( $jpeg_header_data[$i]['SegData'], "Meta\x00\x00", 6) == 0 ) || + ( strncmp ( $jpeg_header_data[$i]['SegData'], "META\x00\x00", 6) == 0 ) ) + { + // Save the location of the Meta segment + $Meta_Location = $i; + } + } + } + + // Check if an EXIF segment was found + if ( $Meta_Location == -1 ) + { + // Couldn't find any Meta block to decode + return FALSE; + } + + + $filehnd = @fopen($filename, 'rb'); + + // Check if the file opened successfully + if ( ! $filehnd ) + { + // Could't open the file - exit + error_log( "Could not open file $filename" ); + return FALSE; + } + + fseek( $filehnd, $jpeg_header_data[$Meta_Location]['SegDataStart'] + 6 ); + + // Decode the Meta segment into an array and return it + $meta = process_TIFF_Header( $filehnd, "Meta" ); + + // Close File + fclose($filehnd); + + return $meta; +} + +/****************************************************************************** +* End of Function: get_Meta +******************************************************************************/ + + + + + + + +/****************************************************************************** +* +* Function: put_Meta_JPEG +* +* Description: Stores information into a Meta APP3 segment from a Meta array. +* +* +* WARNING: Because the Meta (EXIF) standard allows pointers to data +* outside the APP1 segment, if there are any such pointers in +* a makernote, this function will DAMAGE them since it will not +* be aware that there is an external pointer. This will often +* happen with Makernotes that include an embedded thumbnail. +* This damage could be prevented where makernotes can be decoded, +* but currently this is not implemented. +* +* +* Parameters: meta_data - The array of Meta data to insert into the JPEG header +* jpeg_header_data - The JPEG header into which the Meta data +* should be stored, as from get_jpeg_header_data +* +* Returns: jpeg_header_data - JPEG header array with the Meta segment inserted +* FALSE - If an error occured +* +******************************************************************************/ + +function put_Meta_JPEG( $meta_data, $jpeg_header_data ) +{ + // pack the Meta data into its proper format for a JPEG file + $packed_data = get_TIFF_Packed_Data( $meta_data ); + if ( $packed_data === FALSE ) + { + return $jpeg_header_data; + } + + $packed_data = "Meta\x00\x00$packed_data"; + + //Cycle through the header segments + for( $i = 0; $i < count( $jpeg_header_data ); $i++ ) + { + // If we find an APP1 header, + if ( strcmp ( $jpeg_header_data[$i]['SegName'], "APP3" ) == 0 ) + { + // And if it has the Meta label, + if ( ( strncmp ( $jpeg_header_data[$i]['SegData'], "Meta\x00\x00", 6) == 0 ) || + ( strncmp ( $jpeg_header_data[$i]['SegData'], "META\x00\x00", 6) == 0 ) ) + { + // Found a preexisting Meta block - Replace it with the new one and return. + $jpeg_header_data[$i]['SegData'] = $packed_data; + return $jpeg_header_data; + } + } + } + // No preexisting segment segment found, insert a new one at the start of the header data. + + // Determine highest position of an APP segment at or below APP3, so we can put the + // new APP3 at this position + + + $highest_APP = -1; + + //Cycle through the header segments + for( $i = 0; $i < count( $jpeg_header_data ); $i++ ) + { + // Check if we have found an APP segment at or below APP3, + if ( ( $jpeg_header_data[$i]['SegType'] >= 0xE0 ) && ( $jpeg_header_data[$i]['SegType'] <= 0xE3 ) ) + { + // Found an APP segment at or below APP12 + $highest_APP = $i; + } + } + + // No preexisting Meta block found, insert a new one at the start of the header data. + array_splice($jpeg_header_data, $highest_APP + 1 , 0, array( array( "SegType" => 0xE3, + "SegName" => "APP3", + "SegDesc" => $GLOBALS[ "JPEG_Segment_Descriptions" ][ 0xE1 ], + "SegData" => $packed_data ) ) ); + return $jpeg_header_data; + +} + +/****************************************************************************** +* End of Function: put_Meta_JPEG +******************************************************************************/ + + + +/****************************************************************************** +* +* Function: get_EXIF_TIFF +* +* Description: Retrieves information from a Exchangeable Image File Format (EXIF) +* within a TIFF file and returns it in an array. +* +* Parameters: filename - the filename of the TIFF image to process +* +* Returns: OutputArray - Array of EXIF records +* FALSE - If an error occured in decoding +* +******************************************************************************/ + +function get_EXIF_TIFF( $filename ) +{ + // Change: Added as of version 1.11 + // Check if a wrapper is being used - these are not currently supported (see notes at top of file) + if ( ( stristr ( $filename, "http://" ) != FALSE ) || ( stristr ( $filename, "ftp://" ) != FALSE ) ) + { + // A HTTP or FTP wrapper is being used - show a warning and abort + echo "HTTP and FTP wrappers are currently not supported with TIFF - See EXIF/TIFF functionality documentation - a local file must be specified<br>"; + echo "To work on an internet file, copy it locally to start with:<br><br>\n"; + echo "\$newfilename = tempnam ( \$dir, \"tmptiff\" );<br>\n"; + echo "copy ( \"http://whatever.com\", \$newfilename );<br><br>\n"; + return FALSE; + } + + + $filehnd = @fopen($filename, 'rb'); + + // Check if the file opened successfully + if ( ! $filehnd ) + { + // Could't open the file - exit + error_log( "Could not open file $filename" ); + return FALSE; + } + + // Decode the Exif segment into an array and return it + $exif_data = process_TIFF_Header( $filehnd, "TIFF" ); + + // Close File + fclose($filehnd); + return $exif_data; +} + +/****************************************************************************** +* End of Function: get_EXIF_TIFF +******************************************************************************/ + + + + +/****************************************************************************** +* +* Function: Interpret_EXIF_to_HTML +* +* Description: Generates html detailing the contents an APP1 EXIF array +* which was retrieved with a get_EXIF_.... function. +* Can also be used for APP3 Meta arrays. +* +* Parameters: Exif_array - the EXIF array,as read from get_EXIF_.... +* filename - the name of the Image file being processed ( used +* by scripts which displays EXIF thumbnails) +* +* Returns: output_str - A string containing the HTML +* +******************************************************************************/ + +function Interpret_EXIF_to_HTML( $Exif_array, $filename ) +{ + // Create the string to receive the html output + $output_str = ""; + + // Check if the array to process is valid + if ( $Exif_array === FALSE ) + { + // Exif Array is not valid - abort processing + return $output_str; + } + + // Ouput the heading according to what type of tags were used in processing + if ( $Exif_array[ 'Tags Name' ] == "TIFF" ) + { + $output_str .= "<h2 class=\"EXIF_Main_Heading\">Contains Exchangeable Image File Format (EXIF) Information</h2>\n"; + } + else if ( $Exif_array[ 'Tags Name' ] == "Meta" ) + { + $output_str .= "<h2 class=\"EXIF_Main_Heading\">Contains META Information (APP3)</h2>\n"; + } + else + { + $output_str .= "<h2 class=\"EXIF_Main_Heading\">Contains " . $Exif_array[ 'Tags Name' ] . " Information</h2>\n"; + } + + + // Check that there are actually items to process in the array + if ( count( $Exif_array ) < 1 ) + { + // No items to process in array - abort processing + return $output_str; + } + + // Output secondary heading + $output_str .= "<h3 class=\"EXIF_Secondary_Heading\">Main Image Information</h2>\n"; + + // Interpret the zeroth IFD to html + $output_str .= interpret_IFD( $Exif_array[0], $filename, $Exif_array['Byte_Align'] ); + + // Check if there is a first IFD to process + if ( array_key_exists( 1, $Exif_array ) ) + { + // There is a first IFD for a thumbnail + // Add a heading for it to the output + $output_str .= "<h3 class=\"EXIF_Secondary_Heading\">Thumbnail Information</h2>\n"; + + // Interpret the IFD to html and add it to the output + $output_str .= interpret_IFD( $Exif_array[1], $filename, $Exif_array['Byte_Align'] ); + } + + // Cycle through any other IFD's + $i = 2; + while ( array_key_exists( $i, $Exif_array ) ) + { + // Add a heading for the IFD + $output_str .= "<h3 class=\"EXIF_Secondary_Heading\">Image File Directory (IFD) $i Information</h2>\n"; + + // Interpret the IFD to html and add it to the output + $output_str .= interpret_IFD( $Exif_array[$i], $filename, $Exif_array['Byte_Align'] ); + $i++; + } + + // Return the resulting HTML + return $output_str; +} + +/****************************************************************************** +* End of Function: Interpret_EXIF_to_HTML +******************************************************************************/ + + + + + + + + + + + + + + + + +/****************************************************************************** +* +* INTERNAL FUNCTIONS +* +******************************************************************************/ + + + + + + + + + + + +/****************************************************************************** +* +* Internal Function: get_TIFF_Packed_Data +* +* Description: Packs TIFF IFD data from EXIF or Meta into a form ready for +* either a JPEG EXIF/Meta segment or a TIFF file +* This function attempts to protect the contents of an EXIF makernote, +* by ensuring that it remains in the same position relative to the +* TIFF header +* +* Parameters: tiff_data - the EXIF array,as read from get_EXIF_JPEG or get_Meta_JPEG +* +* Returns: packed_data - A string containing packed segment +* +******************************************************************************/ + +function get_TIFF_Packed_Data( $tiff_data ) +{ + // Check that the segment is valid + if ( $tiff_data === FALSE ) + { + return FALSE; + } + + // Get the byte alignment + $Byte_Align = $tiff_data['Byte_Align']; + + // Add the Byte Alignment to the Packed data + $packed_data = $Byte_Align; + + // Add the TIFF ID to the Packed Data + $packed_data .= put_IFD_Data_Type( 42, 3, $Byte_Align ); + + // Create a string for the makernote + $makernote = ""; + + // Check if the makernote exists + if ( $tiff_data[ 'Makernote_Tag' ] !== FALSE ) + { + // A makernote exists - We need to ensure that it stays in the same position as it was + // Put the Makernote before any of the IFD's by padding zeros to the correct offset + $makernote .= str_repeat("\x00",( $tiff_data[ 'Makernote_Tag' ][ 'Offset' ] - 8 ) ); + $makernote .= $tiff_data[ 'Makernote_Tag' ]['Data']; + } + + // Calculage where the zeroth ifd will be + $ifd_offset = strlen( $makernote ) + 8; + + // Add the Zeroth IFD pointer to the packed data + $packed_data .= put_IFD_Data_Type( $ifd_offset, 4, $Byte_Align ); + + // Add the makernote to the packed data (if there was one) + $packed_data .= $makernote; + + //Add the IFD's to the packed data + $packed_data .= get_IFD_Array_Packed_Data( $tiff_data, $ifd_offset, $Byte_Align ); + + // Return the result + return $packed_data; +} + +/****************************************************************************** +* End of Function: get_TIFF_Packed_Data +******************************************************************************/ + + + + +/****************************************************************************** +* +* Internal Function: get_IFD_Array_Packed_Data +* +* Description: Packs a chain of IFD's from EXIF or Meta segments into a form +* ready for either a JPEG EXIF/Meta segment or a TIFF file +* +* Parameters: ifd_data - the IFD chain array, as read from get_EXIF_JPEG or get_Meta_JPEG +* Zero_IFD_offset - The offset to the first IFD from the start of the TIFF header +* Byte_Align - the Byte alignment to use - "MM" or "II" +* +* Returns: packed_data - A string containing packed IFD's +* +******************************************************************************/ + +function get_IFD_Array_Packed_Data( $ifd_data, $Zero_IFD_offset, $Byte_Align ) +{ + // Create a string to receive the packed output + $packed_data = ""; + + // Count the IFDs + $ifd_count = 0; + foreach( $ifd_data as $key => $IFD ) + { + // Make sure we only count the IFD's, not other information keys + if ( is_numeric( $key ) ) + { + $ifd_count++; + } + } + + + // Cycle through each IFD, + for ( $ifdno = 0; $ifdno < $ifd_count; $ifdno++ ) + { + // Check if this IFD is the last one + if ( $ifdno == $ifd_count - 1 ) + { + // This IFD is the last one, get it's packed data + $packed_data .= get_IFD_Packed_Data( $ifd_data[ $ifdno ], $Zero_IFD_offset +strlen($packed_data), $Byte_Align, FALSE ); + } + else + { + // This IFD is NOT the last one, get it's packed data + $packed_data .= get_IFD_Packed_Data( $ifd_data[ $ifdno ], $Zero_IFD_offset +strlen($packed_data), $Byte_Align, TRUE ); + } + + } + + // Return the packed output + return $packed_data; +} + +/****************************************************************************** +* End of Function: get_IFD_Array_Packed_Data +******************************************************************************/ + + + +/****************************************************************************** +* +* Internal Function: get_IFD_Packed_Data +* +* Description: Packs an IFD from EXIF or Meta segments into a form +* ready for either a JPEG EXIF/Meta segment or a TIFF file +* +* Parameters: ifd_data - the IFD chain array, as read from get_EXIF_JPEG or get_Meta_JPEG +* IFD_offset - The offset to the IFD from the start of the TIFF header +* Byte_Align - the Byte alignment to use - "MM" or "II" +* Another_IFD - boolean - false if this is the last IFD in the chain +* - true if it is not the last +* +* Returns: packed_data - A string containing packed IFD's +* +******************************************************************************/ + +function get_IFD_Packed_Data( $ifd_data, $IFD_offset, $Byte_Align, $Another_IFD ) +{ + + $ifd_body_str = ""; + $ifd_data_str = ""; + + $Tag_Definitions_Name = $ifd_data[ 'Tags Name' ]; + + + // Count the Tags in this IFD + $tag_count = 0; + foreach( $ifd_data as $key => $tag ) + { + // Make sure we only count the Tags, not other information keys + if ( is_numeric( $key ) ) + { + $tag_count++; + } + } + + // Add the Tag count to the packed data + $packed_data = put_IFD_Data_Type( $tag_count, 3, $Byte_Align ); + + // Calculate the total length of the IFD (without the offset data) + $IFD_len = 2 + $tag_count * 12 + 4; + + + // Cycle through each tag + foreach( $ifd_data as $key => $tag ) + { + // Make sure this is a tag, not another information key + if ( is_numeric( $key ) ) + { + + // Add the tag number to the packed data + $ifd_body_str .= put_IFD_Data_Type( $tag[ 'Tag Number' ], 3, $Byte_Align ); + + // Add the Data type to the packed data + $ifd_body_str .= put_IFD_Data_Type( $tag['Data Type'], 3, $Byte_Align ); + + // Check if this is a Print Image Matching entry + if ( $tag['Type'] == "PIM" ) + { + // This is a Print Image Matching entry, + // encode it + $data = Encode_PIM( $tag, $Byte_Align ); + } + // Check if this is a IPTC/NAA Record within the EXIF IFD + else if ( ( ( $Tag_Definitions_Name == "EXIF" ) || ( $Tag_Definitions_Name == "TIFF" ) ) && + ( $tag[ 'Tag Number' ] == 33723 ) ) + { + // This is a IPTC/NAA Record, encode it + $data = put_IPTC( $tag['Data'] ); + } + // Change: Check for embedded XMP as of version 1.11 + // Check if this is a XMP Record within the EXIF IFD + else if ( ( ( $Tag_Definitions_Name == "EXIF" ) || ( $Tag_Definitions_Name == "TIFF" ) ) && + ( $tag[ 'Tag Number' ] == 700 ) ) + { + // This is a XMP Record, encode it + $data = write_XMP_array_to_text( $tag['Data'] ); + } + // Change: Check for embedded IRB as of version 1.11 + // Check if this is a Photoshop IRB Record within the EXIF IFD + else if ( ( ( $Tag_Definitions_Name == "EXIF" ) || ( $Tag_Definitions_Name == "TIFF" ) ) && + ( $tag[ 'Tag Number' ] == 34377 ) ) + { + // This is a Photoshop IRB Record, encode it + $data = pack_Photoshop_IRB_Data( $tag['Data'] ); + } + // Exif Thumbnail Offset + else if ( ( $tag[ 'Tag Number' ] == 513 ) && ( $Tag_Definitions_Name == "TIFF" ) ) + { + // The Exif Thumbnail Offset is a pointer but of type Long, not Unknown + // Hence we need to put the data into the packed string separately + // Calculate the thumbnail offset + $data_offset = $IFD_offset + $IFD_len + strlen($ifd_data_str); + + // Create the Offset for the IFD + $data = put_IFD_Data_Type( $data_offset, 4, $Byte_Align ); + + // Store the thumbnail + $ifd_data_str .= $tag['Data']; + } + // Exif Thumbnail Length + else if ( ( $tag[ 'Tag Number' ] == 514 ) && ( $Tag_Definitions_Name == "TIFF" ) ) + { + // Encode the Thumbnail Length + $data = put_IFD_Data_Type( strlen($ifd_data[513]['Data']), 4, $Byte_Align ); + } + // Sub-IFD + else if ( $tag['Type'] == "SubIFD" ) + { + // This is a Sub-IFD + // Calculate the offset to the start of the Sub-IFD + $data_offset = $IFD_offset + $IFD_len + strlen($ifd_data_str); + // Get the packed data for the IFD chain as the data for this tag + $data = get_IFD_Array_Packed_Data( $tag['Data'], $data_offset, $Byte_Align ); + } + else + { + // Not a special tag + + // Create a string to receive the data + $data = ""; + + // Check if this is a type Unknown tag + if ( $tag['Data Type'] != 7 ) + { + // NOT type Unknown + // Cycle through each data value and add it to the data string + foreach( $tag[ 'Data' ] as $data_val ) + { + $data .= put_IFD_Data_Type( $data_val, $tag['Data Type'], $Byte_Align ); + } + } + else + { + // This is a type Unknown - just add the data as is to the data string + $data .= $tag[ 'Data' ]; + } + } + + // Pad the data string out to at least 4 bytes + $data = str_pad ( $data, 4, "\x00" ); + + + // Check if the data type is an ASCII String or type Unknown + if ( ( $tag['Data Type'] == 2 ) || ( $tag['Data Type'] == 7 ) ) + { + // This is an ASCII String or type Unknown + // Add the Length of the string to the packed data as the Count + $ifd_body_str .= put_IFD_Data_Type( strlen($data), 4, $Byte_Align ); + } + else + { + // Add the array count to the packed data as the Count + $ifd_body_str .= put_IFD_Data_Type( count($tag[ 'Data' ]), 4, $Byte_Align ); + } + + + // Check if the data is over 4 bytes long + if ( strlen( $data ) > 4 ) + { + // Data is longer than 4 bytes - it needs to be offset + // Check if this entry is the Maker Note + if ( ( $Tag_Definitions_Name == "EXIF" ) && ( $tag[ 'Tag Number' ] == 37500 ) ) + { + // This is the makernote - It will have already been stored + // at its original offset to help preserve it + // all we need to do is add the Offset to the IFD packed data + $data_offset = $tag[ 'Offset' ]; + + $ifd_body_str .= put_IFD_Data_Type( $data_offset, 4, $Byte_Align ); + } + else + { + // This is NOT the makernote + // Calculate the data offset + $data_offset = $IFD_offset + $IFD_len + strlen($ifd_data_str); + + // Add the offset to the IFD packed data + $ifd_body_str .= put_IFD_Data_Type( $data_offset, 4, $Byte_Align ); + + // Add the data to the offset packed data + $ifd_data_str .= $data; + } + } + else + { + // Data is less than or equal to 4 bytes - Add it to the packed IFD data as is + $ifd_body_str .= $data; + } + + } + } + + // Assemble the IFD body onto the packed data + $packed_data .= $ifd_body_str; + + // Check if there is another IFD after this one + if( $Another_IFD === TRUE ) + { + // There is another IFD after this + // Calculate the Next-IFD offset so that it goes immediately after this IFD + $next_ifd_offset = $IFD_offset + $IFD_len + strlen($ifd_data_str); + } + else + { + // There is NO IFD after this - indicate with offset=0 + $next_ifd_offset = 0; + } + + // Add the Next-IFD offset to the packed data + $packed_data .= put_IFD_Data_Type( $next_ifd_offset, 4, $Byte_Align ); + + // Add the offset data to the packed data + $packed_data .= $ifd_data_str; + + // Return the resulting packed data + return $packed_data; +} + +/****************************************************************************** +* End of Function: get_IFD_Packed_Data +******************************************************************************/ + + + + + +/****************************************************************************** +* +* Internal Function: process_TIFF_Header +* +* Description: Decodes the information stored in a TIFF header and it's +* Image File Directories (IFD's). This information is returned +* in an array +* +* Parameters: filehnd - The handle of a open image file, positioned at the +* start of the TIFF header +* Tag_Definitions_Name - The name of the Tag Definitions group +* within the global array IFD_Tag_Definitions +* +* +* Returns: OutputArray - Array of IFD records +* FALSE - If an error occured in decoding +* +******************************************************************************/ + +function process_TIFF_Header( $filehnd, $Tag_Definitions_Name ) +{ + + + // Save the file position where the TIFF header starts, as offsets are relative to this position + $Tiff_start_pos = ftell( $filehnd ); + + + + // Read the eight bytes of the TIFF header + $DataStr = network_safe_fread( $filehnd, 8 ); + + // Check that we did get all eight bytes + if ( strlen( $DataStr ) != 8 ) + { + return FALSE; // Couldn't read the TIFF header properly + } + + $pos = 0; + // First two bytes indicate the byte alignment - should be 'II' or 'MM' + // II = Intel (LSB first, MSB last - Little Endian) + // MM = Motorola (MSB first, LSB last - Big Endian) + $Byte_Align = substr( $DataStr, $pos, 2 ); + + + + // Check the Byte Align Characters for validity + if ( ( $Byte_Align != "II" ) && ( $Byte_Align != "MM" ) ) + { + // Byte align field is invalid - we won't be able to decode file + return FALSE; + } + + // Skip over the Byte Align field which was just read + $pos += 2; + + // Next two bytes are TIFF ID - should be value 42 with the appropriate byte alignment + $TIFF_ID = substr( $DataStr, $pos, 2 ); + + if ( get_IFD_Data_Type( $TIFF_ID, 3, $Byte_Align ) != 42 ) + { + // TIFF header ID not found + return FALSE; + } + + // Skip over the TIFF ID field which was just read + $pos += 2; + + + // Next four bytes are the offset to the first IFD + $offset_str = substr( $DataStr, $pos, 4 ); + $offset = get_IFD_Data_Type( $offset_str, 4, $Byte_Align ); + + // Done reading TIFF Header + + + // Move to first IFD + + if ( fseek( $filehnd, $Tiff_start_pos + $offset ) !== 0 ) + { + // Error seeking to position of first IFD + return FALSE; + } + + + + // Flag that a makernote has not been found yet + $GLOBALS[ "Maker_Note_Tag" ] = FALSE; + + // Read the IFD chain into an array + $Output_Array = read_Multiple_IFDs( $filehnd, $Tiff_start_pos, $Byte_Align, $Tag_Definitions_Name ); + + // Check if a makernote was found + if ( $GLOBALS[ "Maker_Note_Tag" ] != FALSE ) + { + // Makernote was found - Process it + // The makernote needs to be processed after all other + // tags as it may require some of the other tags in order + // to be processed properly + $GLOBALS[ "Maker_Note_Tag" ] = Read_Makernote_Tag( $GLOBALS[ "Maker_Note_Tag" ], $Output_Array, $filehnd ); + + } + + $Output_Array[ 'Makernote_Tag' ] = $GLOBALS[ "Maker_Note_Tag" ]; + + // Save the Name of the Tags used in the output array + $Output_Array[ 'Tags Name' ] = $Tag_Definitions_Name; + + + + // Save the Byte alignment + $Output_Array['Byte_Align'] = $Byte_Align; + + + // Return the output array + return $Output_Array ; +} + +/****************************************************************************** +* End of Function: process_TIFF_Header +******************************************************************************/ + + + + + + +/****************************************************************************** +* +* Internal Function: read_Multiple_IFDs +* +* Description: Reads and interprets a chain of standard Image File Directories (IFD's), +* and returns the entries in an array. This chain is made up from IFD's +* which have a pointer to the next IFD. IFD's are read until the next +* pointer indicates there are no more +* +* Parameters: filehnd - a handle for the image file being read, positioned at the +* start of the IFD chain +* Tiff_offset - The offset of the TIFF header from the start of the file +* Byte_Align - either "MM" or "II" indicating Motorola or Intel Byte alignment +* Tag_Definitions_Name - The name of the Tag Definitions group within the global array IFD_Tag_Definitions +* local_offsets - True indicates that offset data should be interpreted as being relative to the start of the currrent entry +* False (normal) indicates offests are relative to start of Tiff header as per IFD standard +* read_next_ptr - True (normal) indicates that a pointer to the next IFD should be read at the end of the IFD +* False indicates that no pointer follows the IFD +* +* +* Returns: OutputArray - Array of IFD entries +* +******************************************************************************/ + +function read_Multiple_IFDs( $filehnd, $Tiff_offset, $Byte_Align, $Tag_Definitions_Name, $local_offsets = FALSE, $read_next_ptr = TRUE ) +{ + // Start at the offset of the first IFD + $Next_Offset = 0; + + do + { + // Read an IFD + list($IFD_Array , $Next_Offset) = read_IFD_universal( $filehnd, $Tiff_offset, $Byte_Align, $Tag_Definitions_Name, $local_offsets, $read_next_ptr ); + + // Move to the position of the next IFD + if ( fseek( $filehnd, $Tiff_offset + $Next_Offset ) !== 0 ) + { + // Error seeking to position of next IFD + error_log( "Error: Corrupted EXIF" ); + return FALSE; + } + + $Output_Array[] = $IFD_Array; + + + } while ( $Next_Offset != 0 ); // Until the Next IFD Offset is zero + + + // return resulting array + + return $Output_Array ; +} + +/****************************************************************************** +* End of Function: read_Multiple_IFDs +******************************************************************************/ + + + + + + + +/****************************************************************************** +* +* Internal Function: read_IFD_universal +* +* Description: Reads and interprets a standard or Non-standard Image File +* Directory (IFD), and returns the entries in an array +* +* Parameters: filehnd - a handle for the image file being read, positioned at the start +* of the IFD +* Tiff_offset - The offset of the TIFF header from the start of the file +* Byte_Align - either "MM" or "II" indicating Motorola or Intel Byte alignment +* Tag_Definitions_Name - The name of the Tag Definitions group within the global array IFD_Tag_Definitions +* local_offsets - True indicates that offset data should be interpreted as being relative to the start of the currrent entry +* False (normal) indicates offests are relative to start of Tiff header as per IFD standard +* read_next_ptr - True (normal) indicates that a pointer to the next IFD should be read at the end of the IFD +* False indicates that no pointer follows the IFD +* +* Returns: OutputArray - Array of IFD entries +* Next_Offset - Offset to next IFD (zero = no next IFD) +* +******************************************************************************/ + +function read_IFD_universal( $filehnd, $Tiff_offset, $Byte_Align, $Tag_Definitions_Name, $local_offsets = FALSE, $read_next_ptr = TRUE ) +{ + if ( ( $filehnd == NULL ) || ( feof( $filehnd ) ) ) + { + return array (FALSE , 0); + } + + // Record the Name of the Tag Group used for this IFD in the output array + $OutputArray[ 'Tags Name' ] = $Tag_Definitions_Name; + + // Record the offset of the TIFF header in the output array + $OutputArray[ 'Tiff Offset' ] = $Tiff_offset; + + // First 2 bytes of IFD are number of entries in the IFD + $No_Entries_str = network_safe_fread( $filehnd, 2 ); + $No_Entries = get_IFD_Data_Type( $No_Entries_str, 3, $Byte_Align ); + + + // If the data is corrupt, the number of entries may be huge, which will cause errors + // This is often caused by a lack of a Next-IFD pointer + if ( $No_Entries> 10000 ) + { + // Huge number of entries - abort + // error_log( "Error: huge number of EXIF entries - EXIF is probably Corrupted" ); + + return array ( FALSE , 0); + } + + // If the data is corrupt or just stupid, the number of entries may zero, + // Indicate this by returning false + if ( $No_Entries === 0 ) + { + // No entries - abort + return array ( FALSE , 0); + } + + // Save the file position where first IFD record starts as non-standard offsets + // need to know this to calculate an absolute offset + $IFD_first_rec_pos = ftell( $filehnd ); + + + // Read in the IFD structure + $IFD_Data = network_safe_fread( $filehnd, 12 * $No_Entries ); + + // Check if the entire IFD was able to be read + if ( strlen( $IFD_Data ) != (12 * $No_Entries) ) + { + // Couldn't read the IFD Data properly, Some Casio files have no Next IFD pointer, hence cause this error + error_log( "Error: EXIF Corrupted" ); + return array(FALSE, 0); + } + + + // Last 4 bytes of a standard IFD are the offset to the next IFD + // Some NON-Standard IFD implementations do not have this, hence causing problems if it is read + + // If the Next IFD pointer has been requested to be read, + if ( $read_next_ptr ) + { + // Read the pointer to the next IFD + + $Next_Offset_str = network_safe_fread( $filehnd, 4 ); + $Next_Offset = get_IFD_Data_Type( $Next_Offset_str, 4, $Byte_Align ); + } + else + { + // Otherwise set the pointer to zero ( no next IFD ) + $Next_Offset = 0; + } + + + + // Initialise current position to the start + $pos = 0; + + + // Loop for reading IFD entries + + for ( $i = 0; $i < $No_Entries; $i++ ) + { + // First 2 bytes of IFD entry are the tag number ( Unsigned Short ) + $Tag_No_str = substr( $IFD_Data, $pos, 2 ); + $Tag_No = get_IFD_Data_Type( $Tag_No_str, 3, $Byte_Align ); + $pos += 2; + + // Next 2 bytes of IFD entry are the data format ( Unsigned Short ) + $Data_Type_str = substr( $IFD_Data, $pos, 2 ); + $Data_Type = get_IFD_Data_Type( $Data_Type_str, 3, $Byte_Align ); + $pos += 2; + + // If Datatype is not between 1 and 12, then skip this entry, it is probably corrupted or custom + if (( $Data_Type > 12 ) || ( $Data_Type < 1 ) ) + { + $pos += 8; + continue 1; // Stop trying to process the tag any further and skip to the next one + } + + // Next 4 bytes of IFD entry are the data count ( Unsigned Long ) + $Data_Count_str = substr( $IFD_Data, $pos, 4 ); + $Data_Count = get_IFD_Data_Type( $Data_Count_str, 4, $Byte_Align ); + $pos += 4; + + if ( $Data_Count > 100000 ) + { + // error_log( "Error: huge EXIF data count - EXIF is probably Corrupted" ); + + // Some Casio files have no Next IFD pointer, hence cause errors + + return array ( FALSE , 0); + } + + // Total Data size is the Data Count multiplied by the size of the Data Type + $Total_Data_Size = $GLOBALS['IFD_Data_Sizes'][ $Data_Type ] * $Data_Count; + + $Data_Start_pos = -1; + + // If the total data size is larger than 4 bytes, then the data part is the offset to the real data + if ( $Total_Data_Size > 4 ) + { + // Not enough room for data - offset provided instead + $Data_Offset_str = substr( $IFD_Data, $pos, 4 ); + $Data_Start_pos = get_IFD_Data_Type( $Data_Offset_str, 4, $Byte_Align ); + + + // In some NON-STANDARD makernotes, the offset is relative to the start of the current IFD entry + if ( $local_offsets ) + { + // This is a NON-Standard IFD, seek relative to the start of the current tag + fseek( $filehnd, $IFD_first_rec_pos + $pos - 8 + $Data_Start_pos ); + } + else + { + // This is a normal IFD, seek relative to the start of the TIFF header + fseek( $filehnd, $Tiff_offset + $Data_Start_pos ); + } + + // Read the data block from the offset position + $DataStr = network_safe_fread( $filehnd, $Total_Data_Size ); + } + else + { + // The data block is less than 4 bytes, and is provided in the IFD entry, so read it + $DataStr = substr( $IFD_Data, $pos, $Total_Data_Size ); + } + + // Increment the position past the data + $pos += 4; + + + // Now create the entry for output array + + $Data_Array = array( ); + + + // Read the data items from the data block + + if ( ( $Data_Type != 2 ) && ( $Data_Type != 7 ) ) + { + // The data type is Numerical, Read the data items from the data block + for ( $j = 0; $j < $Data_Count; $j++ ) + { + $Part_Data_Str = substr( $DataStr, $j * $GLOBALS['IFD_Data_Sizes'][ $Data_Type ], $GLOBALS['IFD_Data_Sizes'][ $Data_Type ] ); + $Data_Array[] = get_IFD_Data_Type( $Part_Data_Str, $Data_Type, $Byte_Align ); + } + } + elseif ( $Data_Type == 2 ) + { + // The data type is String(s) (type 2) + + // Strip the last terminating Null + $DataStr = substr( $DataStr, 0, strlen($DataStr)-1 ); + + // Split the data block into multiple strings whereever there is a Null + $Data_Array = explode( "\x00", $DataStr ); + } + else + { + // The data type is Unknown (type 7) + // Do nothing to data + $Data_Array = $DataStr; + } + + + // If this is a Sub-IFD entry, + if ( ( array_key_exists( $Tag_No, $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name] ) ) && + ( "SubIFD" == $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name][ $Tag_No ]['Type'] ) ) + { + // This is a Sub-IFD entry, go and process the data forming Sub-IFD and use its output array as the new data for this entry + fseek( $filehnd, $Tiff_offset + $Data_Array[0] ); + $Data_Array = read_Multiple_IFDs( $filehnd, $Tiff_offset, $Byte_Align, $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name][ $Tag_No ]['Tags Name'] ); + } + + $desc = ""; + $units = ""; + + // Check if this tag exists in the list of tag definitions, + + if ( array_key_exists ( $Tag_No, $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name]) ) + { + + if ( array_key_exists ( 'Description', $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name][ $Tag_No ] ) ) + { + $desc = $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name][ $Tag_No ]['Description']; + } + + if ( array_key_exists ( 'Units', $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name][ $Tag_No ] ) ) + { + $units = $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name][ $Tag_No ]['Units']; + } + + // Tag exists in definitions, append details to output array + $OutputArray[ $Tag_No ] = array ( "Tag Number" => $Tag_No, + "Tag Name" => $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name][ $Tag_No ]['Name'], + "Tag Description" => $desc, + "Data Type" => $Data_Type, + "Type" => $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name][ $Tag_No ]['Type'], + "Units" => $units, + "Data" => $Data_Array ); + + } + else + { + // Tag doesnt exist in definitions, append unknown details to output array + + $OutputArray[ $Tag_No ] = array ( "Tag Number" => $Tag_No, + "Tag Name" => "Unknown Tag #" . $Tag_No, + "Tag Description" => "", + "Data Type" => $Data_Type, + "Type" => "Unknown", + "Units" => "", + "Data" => $Data_Array ); + } + + + + // Some information of type "Unknown" (type 7) might require information about + // how it's position and byte alignment in order to be decoded + if ( $Data_Type == 7 ) + { + $OutputArray[ $Tag_No ]['Offset'] = $Data_Start_pos; + $OutputArray[ $Tag_No ]['Byte Align'] = $Byte_Align; + } + + + //////////////////////////////////////////////////////////////////////// + // Special Data handling + //////////////////////////////////////////////////////////////////////// + + + // Check if this is a Print Image Matching entry + if ( $OutputArray[ $Tag_No ]['Type'] == "PIM" ) + { + // This is a Print Image Matching entry, decode it. + $OutputArray[ $Tag_No ] = Decode_PIM( $OutputArray[ $Tag_No ], $Tag_Definitions_Name ); + } + + + // Interpret the entry into a text string using a custom interpreter + $text_val = get_Tag_Text_Value( $OutputArray[ $Tag_No ], $Tag_Definitions_Name ); + + // Check if a text string was generated + if ( $text_val !== FALSE ) + { + // A string was generated, append it to the output array entry + $OutputArray[ $Tag_No ]['Text Value'] = $text_val; + $OutputArray[ $Tag_No ]['Decoded'] = TRUE; + } + else + { + // A string was NOT generated, append a generic string to the output array entry + $OutputArray[ $Tag_No ]['Text Value'] = get_IFD_value_as_text( $OutputArray[ $Tag_No ] ) . " " . $units; + $OutputArray[ $Tag_No ]['Decoded'] = FALSE; + } + + + + + // Check if this entry is the Maker Note + if ( ( $Tag_Definitions_Name == "EXIF" ) && ( $Tag_No == 37500 ) ) + { + + // Save some extra information which will allow Makernote Decoding with the output array entry + $OutputArray[ $Tag_No ]['Offset'] = $Data_Start_pos; + $OutputArray[ $Tag_No ][ 'Tiff Offset' ] = $Tiff_offset; + $OutputArray[ $Tag_No ]['ByteAlign'] = $Byte_Align; + + // Save a pointer to this entry for Maker note processing later + $GLOBALS[ "Maker_Note_Tag" ] = & $OutputArray[ $Tag_No ]; + } + + + // Check if this is a IPTC/NAA Record within the EXIF IFD + if ( ( ( $Tag_Definitions_Name == "EXIF" ) || ( $Tag_Definitions_Name == "TIFF" ) ) && + ( $Tag_No == 33723 ) ) + { + // This is a IPTC/NAA Record, interpret it and put result in the data for this entry + $OutputArray[ $Tag_No ]['Data'] = get_IPTC( $DataStr ); + $OutputArray[ $Tag_No ]['Decoded'] = TRUE; + } + // Change: Check for embedded XMP as of version 1.11 + // Check if this is a XMP Record within the EXIF IFD + if ( ( ( $Tag_Definitions_Name == "EXIF" ) || ( $Tag_Definitions_Name == "TIFF" ) ) && + ( $Tag_No == 700 ) ) + { + // This is a XMP Record, interpret it and put result in the data for this entry + $OutputArray[ $Tag_No ]['Data'] = read_XMP_array_from_text( $DataStr ); + $OutputArray[ $Tag_No ]['Decoded'] = TRUE; + } + + // Change: Check for embedded IRB as of version 1.11 + // Check if this is a Photoshop IRB Record within the EXIF IFD + if ( ( ( $Tag_Definitions_Name == "EXIF" ) || ( $Tag_Definitions_Name == "TIFF" ) ) && + ( $Tag_No == 34377 ) ) + { + // This is a Photoshop IRB Record, interpret it and put result in the data for this entry + $OutputArray[ $Tag_No ]['Data'] = unpack_Photoshop_IRB_Data( $DataStr ); + $OutputArray[ $Tag_No ]['Decoded'] = TRUE; + } + + // Exif Thumbnail + // Check that both the thumbnail length and offset entries have been processed, + // and that this is one of them + if ( ( ( ( $Tag_No == 513 ) && ( array_key_exists( 514, $OutputArray ) ) ) || + ( ( $Tag_No == 514 ) && ( array_key_exists( 513, $OutputArray ) ) ) ) && + ( $Tag_Definitions_Name == "TIFF" ) ) + { + // Seek to the start of the thumbnail using the offset entry + fseek( $filehnd, $Tiff_offset + $OutputArray[513]['Data'][0] ); + + // Read the thumbnail data, and replace the offset data with the thumbnail + $OutputArray[513]['Data'] = network_safe_fread( $filehnd, $OutputArray[514]['Data'][0] ); + } + + + // Casio Thumbnail + // Check that both the thumbnail length and offset entries have been processed, + // and that this is one of them + if ( ( ( ( $Tag_No == 0x0004 ) && ( array_key_exists( 0x0003, $OutputArray ) ) ) || + ( ( $Tag_No == 0x0003 ) && ( array_key_exists( 0x0004, $OutputArray ) ) ) ) && + ( $Tag_Definitions_Name == "Casio Type 2" ) ) + { + // Seek to the start of the thumbnail using the offset entry + fseek( $filehnd, $Tiff_offset + $OutputArray[0x0004]['Data'][0] ); + + // Read the thumbnail data, and replace the offset data with the thumbnail + $OutputArray[0x0004]['Data'] = network_safe_fread( $filehnd, $OutputArray[0x0003]['Data'][0] ); + } + + // Minolta Thumbnail + // Check that both the thumbnail length and offset entries have been processed, + // and that this is one of them + if ( ( ( ( $Tag_No == 0x0088 ) && ( array_key_exists( 0x0089, $OutputArray ) ) ) || + ( ( $Tag_No == 0x0089 ) && ( array_key_exists( 0x0088, $OutputArray ) ) ) ) && + ( $Tag_Definitions_Name == "Olympus" ) ) + { + + // Seek to the start of the thumbnail using the offset entry + fseek( $filehnd, $Tiff_offset + $OutputArray[0x0088]['Data'][0] ); + + // Read the thumbnail data, and replace the offset data with the thumbnail + $OutputArray[0x0088]['Data'] = network_safe_fread( $filehnd, $OutputArray[0x0089]['Data'][0] ); + + // Sometimes the minolta thumbnail data is empty (or the offset is corrupt, which results in the same thing) + + // Check if the thumbnail data exists + if ( $OutputArray[0x0088]['Data'] != "" ) + { + // Thumbnail exists + + // Minolta Thumbnails are missing their first 0xFF for some reason, + // which is replaced with some weird character, so fix this + $OutputArray[0x0088]['Data']{0} = "\xFF"; + } + else + { + // Thumbnail doesnt exist - make it obvious + $OutputArray[0x0088]['Data'] = FALSE; + } + } + + } + + + + + + + + // Return the array of IFD entries and the offset to the next IFD + + return array ($OutputArray , $Next_Offset); +} + + + +/****************************************************************************** +* End of Function: read_IFD_universal +******************************************************************************/ + + + + + + + + + + + + +/****************************************************************************** +* +* Internal Function: get_Tag_Text_Value +* +* Description: Attempts to interpret an IFD entry into a text string using the +* information in the IFD_Tag_Definitions global array. +* +* Parameters: Tag - The IFD entry to process +* Tag_Definitions_Name - The name of the tag definitions to use from within the IFD_Tag_Definitions global array +* +* Returns: String - if the tag was successfully decoded into a text string +* FALSE - if the tag could not be decoded using the information +* in the IFD_Tag_Definitions global array +* +******************************************************************************/ + +function get_Tag_Text_Value( $Tag, $Tag_Definitions_Name ) +{ + // Check what format the entry is specified as + + if ( $Tag['Type'] == "String" ) + { + // Format is Text String + + // If "Unknown" (type 7) data type, + if ( $Tag['Data Type'] == 7 ) + { + // Return data as is. + return $Tag['Data']; + } + else + { + // Otherwise return the default string value of the datatype + return get_IFD_value_as_text( $Tag ); + } + } + else if ( $Tag['Type'] == "Character Coded String" ) + { + // Format is Character Coded String (First 8 characters indicate coding scheme) + + // Convert Data to a string + if ( $Tag['Data Type'] == 7 ) + { + // If it is type "Unknown" (type 7) use data as is + $data = $Tag['Data']; + } + else + { + // Otherwise use the default string value of the datatype + $data = get_IFD_value_as_text( $Tag ); + } + + // Some implementations allow completely data with no Coding Scheme Name, + // so we need to handle this to avoid errors + if ( trim( $data ) == "" ) + { + return ""; + } + + // Extract the Coding Scheme Name from the first 8 characters + $char_code = substr( $data, 0, 8 ); + + // Extract the Data part from after the first 8 characters + $characters = substr( $data, 8 ); + + // Check coding scheme and interpret as neccessary + + if ( $char_code === "ASCII\x00\x00\x00" ) + { + // ASCII coding - return data as is. + return $characters; + } + elseif ( ( $char_code === "UNICODE\x00" ) || + ( $char_code === "Unicode\x00" ) ) // Note lowercase is non standard + { + // Unicode coding - interpret and return result. + return xml_UTF16_clean( $characters, TRUE ); + } + else + { + // Unknown coding - return string indicating this + return "Unsupported character coding : \"$char_code\"\n\"" . trim($characters) . "\""; + } + break; + } + else if ( $Tag['Type'] == "Numeric" ) + { + // Format is numeric - return default text value with any required units text appended + if ( array_key_exists ( 'Units', $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name][ $Tag["Tag Number"] ] ) ) + { + $units = $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name][ $Tag["Tag Number"] ]['Units']; + } + else + { + $units = ""; + } + return get_IFD_value_as_text( $Tag ) . " " . $units; + } + else if ( $Tag['Type'] == "Lookup" ) + { + // Format is a Lookup Table + + // Get a numeric value to use in lookup + + if ( is_array( $Tag['Data'] ) ) + { + // If data is an array, use first element + $first_val = $Tag['Data'][0]; + } + else if ( is_string( $Tag['Data'] ) ) + { + // If data is a string, use the first character + $first_val = ord($Tag['Data']{0}); + } + else + { + // Otherwise use the data as is + $first_val = $Tag['Data']; + } + + // Check if the data value exists in the lookup table for this IFD entry + if ( array_key_exists( $first_val, $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name][ $Tag["Tag Number"] ] ) ) + { + // Data value exists in lookup table - return the matching string + return $GLOBALS[ "IFD_Tag_Definitions" ][$Tag_Definitions_Name][ $Tag["Tag Number"] ][ $first_val ]; + } + else + { + // Data value doesnt exist in lookup table - return explanation string + return "Unknown Reserved value $first_val "; + } + } + else if ( $Tag['Type'] == "Special" ) + { + // Format is special - interpret to text with special handlers + return get_Special_Tag_Text_Value( $Tag, $Tag_Definitions_Name ); + } + else if ( $Tag['Type'] == "PIM" ) + { + // Format is Print Image Matching info - interpret with custom handler + return get_PIM_Text_Value( $Tag, $Tag_Definitions_Name ); + } + else if ( $Tag['Type'] == "SubIFD" ) + { + // Format is a Sub-IFD - this has no text value + return ""; + } + else + { + // Unknown Format - Couldn't interpret using the IFD_Tag_Definitions global array information + return FALSE; + } +} + +/****************************************************************************** +* End of Function: get_Tag_Text_Value +******************************************************************************/ + + + + + + +/****************************************************************************** +* +* Internal Function: get_Special_Tag_Text_Value +* +* Description: Interprets an IFD entry marked as "Special" in the IFD_Tag_Definitions +* global array into a text string using custom handlers +* +* Parameters: Tag - The IFD entry to process +* Tag_Definitions_Name - The name of the tag definitions to use from within the IFD_Tag_Definitions global array +* +* Returns: String - if the tag was successfully decoded into a text string +* FALSE - if the tag could not be decoded +* +******************************************************************************/ + +function get_Special_Tag_Text_Value( $Tag, $Tag_Definitions_Name ) +{ + // Check what type of IFD is being decoded + + if ( $Tag_Definitions_Name == "TIFF" ) + { + // This is a TIFF IFD (bottom level) + + // Check what tag number the IFD entry has. + switch ( $Tag['Tag Number'] ) + { + case 530: // YCbCr Sub Sampling Entry + + // Data contains two numerical values + + if ( ( $Tag['Data'][0] == 2 ) && ( $Tag['Data'][1] == 1 ) ) + { + // Values are 2,1 - hence YCbCr 4:2:2 + return "YCbCr 4:2:2 ratio of chrominance components to the luminance components"; + } + elseif ( ( $Tag['Data'][0] == 2 ) && ( $Tag['Data'][1] == 2 ) ) + { + // Values are 2,2 - hence YCbCr 4:2:0 + return "YCbCr 4:2:0 ratio of chrominance components to the luminance components"; + } + else + { + // Other values are unknown + return "Unknown Reserved value (" . $Tag['Data'][0] . ")"; + } + break; + + default: + return FALSE; + } + } + else if ( $Tag_Definitions_Name == "EXIF" ) + { + // This is an EXIF IFD + + // Check what tag number the IFD entry has. + switch ( $Tag['Tag Number'] ) + { + + case 37121: // Components configuration + + // Data contains 4 numerical values indicating component type + + $output_str = ""; + + // Cycle through each component + for ( $Num = 0; $Num < 4; $Num++ ) + { + // Construct first part of text string + $output_str .= "Component " . ( $Num + 1 ) . ": "; + + // Construct second part of text string via + // lookup using numerical value + + $value = ord( $Tag['Data']{$Num} ); + switch( $value ) + { + case 0: + $output_str .= "Does not exist\n"; + break; + case 1: + $output_str .= "Y (Luminance)\n"; + break; + case 2: + $output_str .= "Cb (Chroma minus Blue)\n"; + break; + case 3: + $output_str .= "Cr (Chroma minus Red)\n"; + break; + case 4: + $output_str .= "Red\n"; + break; + case 5: + $output_str .= "Green\n"; + break; + case 6: + $output_str .= "Blue\n"; + break; + default: + $output_str .= "Unknown value $value\n"; + }; + } + + // Return the completed string + + return $output_str; + break; + + + + case 41730: // Colour Filter Array Pattern + + // The first two characters are a SHORT for Horizontal repeat pixel unit - + $n_max = get_IFD_Data_Type( substr( $Tag['Data'], 0, 2 ), 3, $Tag['Byte Align'] ); + + // The next two characters are a SHORT for Vertical repeat pixel unit - + $m_max = get_IFD_Data_Type( substr( $Tag['Data'], 2, 2 ), 3, $Tag['Byte Align'] ); + + + // At least one camera type appears to have byte reversed values for N_Max and M_Max + // Check if they need reversing + if ( $n_max > 256 ) + { + $n_max = $n_max/256 + 256*($n_max%256); + } + + if ( $m_max > 256 ) + { + $m_max = $m_max/256 + 256*($m_max%256); + } + + + $output_str = ""; + + + // Cycle through all the elements in the resulting 2 dimensional array, + for( $m = 1; $m <= $m_max; $m++ ) + { + for( $n = 1; $n <= $n_max; $n++ ) + { + + // Append text from a lookup table according to + // the value read for this element + if( isset( $Tag['Data']{($n_max*($m-1)+$n+3)} ) ) { + switch ( ord($Tag['Data']{($n_max*($m-1)+$n+3)}) ) + { + case 0: + $output_str .= "RED "; + break; + case 1: + $output_str .= "GREEN "; + break; + case 2: + $output_str .= "BLUE "; + break; + case 3: + $output_str .= "CYAN "; + break; + case 4: + $output_str .= "MAGENTA "; + break; + case 5: + $output_str .= "YELLOW "; + break; + case 6: + $output_str .= "WHITE "; + break; + default: + $output_str .= "Unknown "; + break; + }; + } + }; + $output_str .= "\n"; + }; + + // Return the resulting string + return $output_str; + break; + + default: + return FALSE; + } + } + else + { + // Unknown IFD type, see if it is part of a makernote + return get_Makernote_Text_Value( $Tag, $Tag_Definitions_Name ); + } + + +} + +/****************************************************************************** +* End of Function: get_Tag_Text_Value +******************************************************************************/ + + + + + + + + +/****************************************************************************** +* +* Function: interpret_IFD +* +* Description: Generates html detailing the contents a single IFD. +* +* Parameters: IFD_array - the array containing an IFD +* filename - the name of the Image file being processed ( used +* by scripts which displays EXIF thumbnails) +* +* Returns: output_str - A string containing the HTML +* +******************************************************************************/ + +function interpret_IFD( $IFD_array, $filename ) +{ + // Create the output string with the table tag + $output_str = "<table class=\"EXIF_Table\" border=1>\n"; + + // Create an extra output string to receive any supplementary html + // which cannot go inside the table + $extra_IFD_str = ""; + + // Check that the IFD array is valid + if ( ( $IFD_array === FALSE ) || ( $IFD_array === NULL ) ) + { + // the IFD array is NOT valid - exit + return ""; + } + + // Check if this is an EXIF IFD and if there is a makernote present + if ( ( $IFD_array['Tags Name'] === "EXIF" ) && + ( ! array_key_exists( 37500, $IFD_array ) ) ) + { + + // This is an EXIF IFD but NO makernote is present - Add a message to the output + $extra_IFD_str .= "<h3 class=\"EXIF_Secondary_Heading\">No Makernote Present</h3>"; + } + + // Cycle through each tag in the IFD + + foreach( $IFD_array as $Tag_ID => $Exif_Tag ) + { + + // Ignore the non numeric elements - they aren't tags + if ( ! is_numeric ( $Tag_ID ) ) + { + // Skip Tags Name + } + // Check if the Tag has been decoded successfully + else if ( $Exif_Tag['Decoded'] == TRUE ) + { + // This tag has been successfully decoded + + // Table cells won't get drawn with nothing in them - + // Ensure that at least a non breaking space exists in them + + if ( trim($Exif_Tag['Text Value']) == "" ) + { + $Exif_Tag['Text Value'] = " "; + } + + // Check if the tag is a sub-IFD + if ( $Exif_Tag['Type'] == "SubIFD" ) + { + // This is a sub-IFD tag + // Add a sub-heading for the sub-IFD + $extra_IFD_str .= "<h3 class=\"EXIF_Secondary_Heading\">" . $Exif_Tag['Tag Name'] . " contents</h3>"; + + // Cycle through each sub-IFD in the chain + foreach ( $Exif_Tag['Data'] as $subIFD ) + { + // Interpret this sub-IFD and add the html to the secondary output + $extra_IFD_str .= interpret_IFD( $subIFD, $filename ); + } + } + // Check if the tag is a makernote + else if ( $Exif_Tag['Type'] == "Maker Note" ) + { + // This is a Makernote Tag + // Add a sub-heading for the Makernote + $extra_IFD_str .= "<h3 class=\"EXIF_Secondary_Heading\">Maker Note Contents</h3>"; + + // Interpret the Makernote and add the html to the secondary output + $extra_IFD_str .= Interpret_Makernote_to_HTML( $Exif_Tag, $filename ); + } + // Check if this is a IPTC/NAA Record within the EXIF IFD + else if ( $Exif_Tag['Type'] == "IPTC" ) + { + // This is a IPTC/NAA Record, interpret it and output to the secondary html + $extra_IFD_str .= "<h3 class=\"EXIF_Secondary_Heading\">Contains IPTC/NAA Embedded in EXIF</h3>"; + $extra_IFD_str .=Interpret_IPTC_to_HTML( $Exif_Tag['Data'] ); + } + // Change: Check for embedded XMP as of version 1.11 + // Check if this is a XMP Record within the EXIF IFD + else if ( $Exif_Tag['Type'] == "XMP" ) + { + // This is a XMP Record, interpret it and output to the secondary html + $extra_IFD_str .= "<h3 class=\"EXIF_Secondary_Heading\">Contains XMP Embedded in EXIF</h3>"; + $extra_IFD_str .= Interpret_XMP_to_HTML( $Exif_Tag['Data'] ); + } + // Change: Check for embedded IRB as of version 1.11 + // Check if this is a Photoshop IRB Record within the EXIF IFD + else if ( $Exif_Tag['Type'] == "IRB" ) + { + // This is a Photoshop IRB Record, interpret it and output to the secondary html + $extra_IFD_str .= "<h3 class=\"EXIF_Secondary_Heading\">Contains Photoshop IRB Embedded in EXIF</h3>"; + $extra_IFD_str .= Interpret_IRB_to_HTML( $Exif_Tag['Data'], $filename ); + } + // Check if the tag is Numeric + else if ( $Exif_Tag['Type'] == "Numeric" ) + { + // Numeric Tag - Output text value as is. + $output_str .= "<tr class=\"EXIF_Table_Row\"><td class=\"EXIF_Caption_Cell\">" . $Exif_Tag['Tag Name'] . "</td><td class=\"EXIF_Value_Cell\">" . $Exif_Tag['Text Value'] . "</td></tr>\n"; + } + else + { + // Other tag - Output text as preformatted + $output_str .= "<tr class=\"EXIF_Table_Row\"><td class=\"EXIF_Caption_Cell\">" . $Exif_Tag['Tag Name'] . "</td><td class=\"EXIF_Value_Cell\"><pre>" . trim( $Exif_Tag['Text Value']) . "</pre></td></tr>\n"; + } + + } + else + { + // Tag has NOT been decoded successfully + // Hence it is either an unknown tag, or one which + // requires processing at the time of html construction + + // Table cells won't get drawn with nothing in them - + // Ensure that at least a non breaking space exists in them + + if ( trim($Exif_Tag['Text Value']) == "" ) + { + $Exif_Tag['Text Value'] = " "; + } + + // Check if this tag is the first IFD Thumbnail + if ( ( $IFD_array['Tags Name'] == "TIFF" ) && + ( $Tag_ID == 513 ) ) + { + // This is the first IFD thumbnail - Add html to the output + + // Change: as of version 1.11 - Changed to make thumbnail link portable across directories + // Build the path of the thumbnail script and its filename parameter to put in a url + $link_str = get_relative_path( dirname(__FILE__) . "/get_exif_thumb.php" , getcwd ( ) ); + $link_str .= "?filename="; + $link_str .= get_relative_path( $filename, dirname(__FILE__) ); + + // Add thumbnail link to html + $output_str .= "<tr class=\"EXIF_Table_Row\"><td class=\"EXIF_Caption_Cell\">" . $Exif_Tag['Tag Name'] . "</td><td class=\"EXIF_Value_Cell\"><a class=\"EXIF_First_IFD_Thumb_Link\" href=\"$link_str\"><img class=\"EXIF_First_IFD_Thumb\" src=\"$link_str\"></a></td></tr>\n"; + } + // Check if this is the Makernote + else if ( $Exif_Tag['Type'] == "Maker Note" ) + { + // This is the makernote, but has not been decoded + // Add a message to the secondary output + $extra_IFD_str .= "<h3 class=\"EXIF_Secondary_Heading\">Makernote Coding Unknown</h3>\n"; + } + else + { + // This is an Unknown Tag + + // Check if the user wants to hide unknown tags + if ( $GLOBALS['HIDE_UNKNOWN_TAGS'] === FALSE ) + { + // User wants to display unknown tags + + // Check if the Data is an ascii string + if ( $Exif_Tag['Data Type'] == 2 ) + { + // This is a Ascii String field - add it preformatted to the output + $output_str .= "<tr class=\"EXIF_Table_Row\"><td class=\"EXIF_Caption_Cell\">" . $Exif_Tag['Tag Name'] . "</td><td class=\"EXIF_Value_Cell\"><pre>" . trim( $Exif_Tag['Text Value'] ) . "</pre></td></tr>\n"; + } + else + { + // Not an ASCII string - add it as is to the output + $output_str .= "<tr class=\"EXIF_Table_Row\"><td class=\"EXIF_Caption_Cell\">" . $Exif_Tag['Tag Name'] . "</td><td class=\"EXIF_Value_Cell\">" . trim( $Exif_Tag['Text Value'] ) . "</td></tr>\n"; + } + } + } + } + } + + // Close the table in the output + $output_str .= "</table>\n"; + + // Add the secondary output at the end of the main output + $output_str .= "$extra_IFD_str\n"; + + // Return the resulting html + return $output_str; +} + +/****************************************************************************** +* End of Function: interpret_IFD +******************************************************************************/ + + + + + + + + + + + + + + + +/****************************************************************************** +* +* Function: get_IFD_Data_Type +* +* Description: Decodes an IFD field value from a binary data string, using +* information supplied about the data type and byte alignment of +* the stored data. +* This function should be used for all datatypes except ASCII strings +* +* Parameters: input_data - a binary data string containing the IFD value, +* must be exact length of the value +* data_type - a number representing the IFD datatype as per the +* TIFF 6.0 specification: +* 1 = Unsigned 8-bit Byte +* 2 = ASCII String +* 3 = Unsigned 16-bit Short +* 4 = Unsigned 32-bit Long +* 5 = Unsigned 2x32-bit Rational +* 6 = Signed 8-bit Byte +* 7 = Undefined +* 8 = Signed 16-bit Short +* 9 = Signed 32-bit Long +* 10 = Signed 2x32-bit Rational +* 11 = 32-bit Float +* 12 = 64-bit Double +* Byte_Align - Indicates the byte alignment of the data. +* MM = Motorola, MSB first, Big Endian +* II = Intel, LSB first, Little Endian +* +* Returns: output - the value of the data (string or numeric) +* +******************************************************************************/ + +function get_IFD_Data_Type( $input_data, $data_type, $Byte_Align ) +{ + $value = NULL; + if( !empty( $input_data ) ) { + // Check if this is a Unsigned Byte, Unsigned Short or Unsigned Long + if (( $data_type == 1 ) || ( $data_type == 3 ) || ( $data_type == 4 )) + { + // This is a Unsigned Byte, Unsigned Short or Unsigned Long + + // Check the byte alignment to see if the bytes need tp be reversed + if ( $Byte_Align == "II" ) + { + // This is in Intel format, reverse it + $input_data = strrev ( $input_data ); + } + + // Convert the binary string to a number and return it + return hexdec( bin2hex( $input_data ) ); + } + // Check if this is a ASCII string type + elseif ( $data_type == 2 ) + { + // Null terminated ASCII string(s) + // The input data may represent multiple strings, as the + // 'count' field represents the total bytes, not the number of strings + // Hence this should not be processed here, as it would have + // to return multiple values instead of a single value + + error_log( "Error - ASCII Strings should not be processed in get_IFD_Data_Type" ); + return "Error Should never get here"; //explode( "\x00", $input_data ); + } + // Check if this is a Unsigned rational type + elseif ( $data_type == 5 ) + { + // This is a Unsigned rational type + + // Check the byte alignment to see if the bytes need to be reversed + if ( $Byte_Align == "MM" ) + { + // Motorola MSB first byte aligment + // Unpack the Numerator and denominator and return them + return @unpack( 'NNumerator/NDenominator', $input_data ); + } + else + { + // Intel LSB first byte aligment + // Unpack the Numerator and denominator and return them + return @unpack( 'VNumerator/VDenominator', $input_data ); + } + } + // Check if this is a Signed Byte, Signed Short or Signed Long + elseif ( ( $data_type == 6 ) || ( $data_type == 8 ) || ( $data_type == 9 ) ) + { + // This is a Signed Byte, Signed Short or Signed Long + + // Check the byte alignment to see if the bytes need to be reversed + if ( $Byte_Align == "II" ) + { + //Intel format, reverse the bytes + $input_data = strrev ( $input_data ); + } + + // Convert the binary string to an Unsigned number + $value = hexdec( bin2hex( $input_data ) ); + + // Convert to signed number + + // Check if it is a Byte above 128 (i.e. a negative number) + if ( ( $data_type == 6 ) && ( $value > 128 ) ) + { + // number should be negative - make it negative + return $value - 256; + } + + // Check if it is a Short above 32767 (i.e. a negative number) + if ( ( $data_type == 8 ) && ( $value > 32767 ) ) + { + // number should be negative - make it negative + return $value - 65536; + } + + // Check if it is a Long above 2147483648 (i.e. a negative number) + if ( ( $data_type == 9 ) && ( $value > 2147483648 ) ) + { + // number should be negative - make it negative + return $value - 4294967296; + } + + // Return the signed number + return $value; + } + // Check if this is Undefined type + elseif ( $data_type == 7 ) + { + // Custom Data - Do nothing + return $input_data; + } + // Check if this is a Signed Rational type + elseif ( $data_type == 10 ) + { + // This is a Signed Rational type + + // Signed Long not available with endian in unpack , use unsigned and convert + + // Check the byte alignment to see if the bytes need to be reversed + if ( $Byte_Align == "MM" ) + { + // Motorola MSB first byte aligment + // Unpack the Numerator and denominator + $value = @unpack( 'NNumerator/NDenominator', $input_data ); + } + else + { + // Intel LSB first byte aligment + // Unpack the Numerator and denominator + $value = @unpack( 'VNumerator/VDenominator', $input_data ); + } + + // Convert the numerator to a signed number + // Check if it is above 2147483648 (i.e. a negative number) + if ( $value['Numerator'] > 2147483648 ) + { + // number is negative + $value['Numerator'] -= 4294967296; + } + + // Convert the denominator to a signed number + // Check if it is above 2147483648 (i.e. a negative number) + if ( $value['Denominator'] > 2147483648 ) + { + // number is negative + $value['Denominator'] -= 4294967296; + } + + // Return the Signed Rational value + return $value; + } + // Check if this is a Float type + elseif ( $data_type == 11 ) + { + // IEEE 754 Float + // TODO - EXIF - IFD datatype Float not implemented yet + return "FLOAT NOT IMPLEMENTED YET"; + } + // Check if this is a Double type + elseif ( $data_type == 12 ) + { + // IEEE 754 Double + // TODO - EXIF - IFD datatype Double not implemented yet + return "DOUBLE NOT IMPLEMENTED YET"; + } + else + { + // Error - Invalid Datatype + return "Invalid Datatype $data_type"; + + } + } else { + return "Invalid Datatype $data_type"; + } + +} + +/****************************************************************************** +* End of Function: get_IFD_Data_Type +******************************************************************************/ + + + + + + +/****************************************************************************** +* +* Function: put_IFD_Data_Type +* +* Description: Encodes an IFD field from a value to a binary data string, using +* information supplied about the data type and byte alignment of +* the stored data. +* +* Parameters: input_data - an IFD data value, numeric or string +* data_type - a number representing the IFD datatype as per the +* TIFF 6.0 specification: +* 1 = Unsigned 8-bit Byte +* 2 = ASCII String +* 3 = Unsigned 16-bit Short +* 4 = Unsigned 32-bit Long +* 5 = Unsigned 2x32-bit Rational +* 6 = Signed 8-bit Byte +* 7 = Undefined +* 8 = Signed 16-bit Short +* 9 = Signed 32-bit Long +* 10 = Signed 2x32-bit Rational +* 11 = 32-bit Float +* 12 = 64-bit Double +* Byte_Align - Indicates the byte alignment of the data. +* MM = Motorola, MSB first, Big Endian +* II = Intel, LSB first, Little Endian +* +* Returns: output - the packed binary string of the data +* +******************************************************************************/ + +function put_IFD_Data_Type( $input_data, $data_type, $Byte_Align ) +{ + // Process according to the datatype + switch ( $data_type ) + { + case 1: // Unsigned Byte - return character as is + return chr($input_data); + break; + + case 2: // ASCII String + // Return the string with terminating null + return $input_data . "\x00"; + break; + + case 3: // Unsigned Short + // Check byte alignment + if ( $Byte_Align == "II" ) + { + // Intel/Little Endian - pack the short and return + return pack( "v", $input_data ); + } + else + { + // Motorola/Big Endian - pack the short and return + return pack( "n", $input_data ); + } + break; + + case 4: // Unsigned Long + // Check byte alignment + if ( $Byte_Align == "II" ) + { + // Intel/Little Endian - pack the long and return + return pack( "V", $input_data ); + } + else + { + // Motorola/Big Endian - pack the long and return + return pack( "N", $input_data ); + } + break; + + case 5: // Unsigned Rational + // Check byte alignment + if ( $Byte_Align == "II" ) + { + // Intel/Little Endian - pack the two longs and return + return pack( "VV", $input_data['Numerator'], $input_data['Denominator'] ); + } + else + { + // Motorola/Big Endian - pack the two longs and return + return pack( "NN", $input_data['Numerator'], $input_data['Denominator'] ); + } + break; + + case 6: // Signed Byte + // Check if number is negative + if ( $input_data < 0 ) + { + // Number is negative - return signed character + return chr( $input_data + 256 ); + } + else + { + // Number is positive - return character + return chr( $input_data ); + } + break; + + case 7: // Unknown - return as is + return $input_data; + break; + + case 8: // Signed Short + // Check if number is negative + if ( $input_data < 0 ) + { + // Number is negative - make signed value + $input_data = $input_data + 65536; + } + // Check byte alignment + if ( $Byte_Align == "II" ) + { + // Intel/Little Endian - pack the short and return + return pack( "v", $input_data ); + } + else + { + // Motorola/Big Endian - pack the short and return + return pack( "n", $input_data ); + } + break; + + case 9: // Signed Long + // Check if number is negative + if ( $input_data < 0 ) + { + // Number is negative - make signed value + $input_data = $input_data + 4294967296; + } + // Check byte alignment + if ( $Byte_Align == "II" ) + { + // Intel/Little Endian - pack the long and return + return pack( "v", $input_data ); + } + else + { + // Motorola/Big Endian - pack the long and return + return pack( "n", $input_data ); + } + break; + + case 10: // Signed Rational + // Check if numerator is negative + if ( $input_data['Numerator'] < 0 ) + { + // Number is numerator - make signed value + $input_data['Numerator'] = $input_data['Numerator'] + 4294967296; + } + // Check if denominator is negative + if ( $input_data['Denominator'] < 0 ) + { + // Number is denominator - make signed value + $input_data['Denominator'] = $input_data['Denominator'] + 4294967296; + } + // Check byte alignment + if ( $Byte_Align == "II" ) + { + // Intel/Little Endian - pack the two longs and return + return pack( "VV", $input_data['Numerator'], $input_data['Denominator'] ); + } + else + { + // Motorola/Big Endian - pack the two longs and return + return pack( "NN", $input_data['Numerator'], $input_data['Denominator'] ); + } + break; + + case 11: // Float + // IEEE 754 Float + // TODO - EXIF - IFD datatype Float not implemented yet + return "FLOAT NOT IMPLEMENTED YET"; + break; + + case 12: // Double + // IEEE 754 Double + // TODO - EXIF - IFD datatype Double not implemented yet + return "DOUBLE NOT IMPLEMENTED YET"; + break; + + default: + // Error - Invalid Datatype + return "Invalid Datatype $data_type"; + break; + + } + + // Shouldn't get here + return FALSE; +} + +/****************************************************************************** +* End of Function: put_IFD_Data_Type +******************************************************************************/ + + + + + +/****************************************************************************** +* +* Function: get_IFD_value_as_text +* +* Description: Decodes an IFD field value from a binary data string, using +* information supplied about the data type and byte alignment of +* the stored data. +* This function should be used for all datatypes except ASCII strings +* +* Parameters: input_data - a binary data string containing the IFD value, +* must be exact length of the value +* data_type - a number representing the IFD datatype as per the +* TIFF 6.0 specification: +* 1 = Unsigned 8-bit Byte +* 2 = ASCII String +* 3 = Unsigned 16-bit Short +* 4 = Unsigned 32-bit Long +* 5 = Unsigned 2x32-bit Rational +* 6 = Signed 8-bit Byte +* 7 = Undefined +* 8 = Signed 16-bit Short +* 9 = Signed 32-bit Long +* 10 = Signed 2x32-bit Rational +* 11 = 32-bit Float +* 12 = 64-bit Double +* Byte_Align - Indicates the byte alignment of the data. +* MM = Motorola, MSB first, Big Endian +* II = Intel, LSB first, Little Endian +* +* Returns: output - the value of the data (string or numeric) +* +******************************************************************************/ + +function get_IFD_value_as_text( $Exif_Tag ) +{ + // Create a string to receive the output text + $output_str = ""; + +if( !empty( $Exif_Tag['Data Type'] ) ) { + // Select Processing method according to the datatype + switch ($Exif_Tag['Data Type']) + { + case 1 : // Unsigned Byte + case 3 : // Unsigned Short + case 4 : // Unsigned Long + case 6 : // Signed Byte + case 8 : // Signed Short + case 9 : // Signed Long + + // Cycle through each of the values for this tag + foreach ( $Exif_Tag['Data'] as $val ) + { + // Check that this isn't the first value, + if ( $output_str != "" ) + { + // This isn't the first value, Add a Comma and Newline to the output + $output_str .= ",\n"; + } + // Add the Value to the output + $output_str .= $val; + } + break; + + case 2 : // ASCII + // Append all the strings together, separated by Newlines + $output_str .= implode ( "\n", $Exif_Tag['Data']); + break; + + case 5 : // Unsigned Rational + case 10: // Signed Rational + + // Cycle through each of the values for this tag + foreach ( $Exif_Tag['Data'] as $val ) + { + // Check that this isn't the first value, + if ( $output_str != "" ) + { + // This isn't the first value, Add a Comma and Newline to the output + $output_str .= ",\n"; + } + + // Add the Full Value to the output + $output_str .= $val['Numerator'] ."/" . $val['Denominator']; + + // Check if division by zero might be a problem + if ( $val['Denominator'] != 0 ) + { + // Denominator is not zero, Add the Decimal Value to the output text + $output_str .= " (" . ($val['Numerator'] / $val['Denominator']) . ")"; + } + } + break; + + case 11: // Float + case 12: // Double + // TODO - EXIF - IFD datatype Double and Float not implemented yet + $output_str .= "Float and Double not implemented yet"; + break; + + case 7 : // Undefined + // Unless the User has asked to see the raw binary data, this + // type should not be displayed + + // Check if the user has requested to see the binary data in hex + if ( $GLOBALS['SHOW_BINARY_DATA_HEX'] == TRUE) + { + // User has requested to see the binary data in hex + // Add the value in hex + $output_str .= "( " . strlen( $Exif_Tag['Data'] ) . " bytes of binary data ): " . bin2hex( $Exif_Tag['Data'] ) ; + } + // Check if the user has requested to see the binary data as is + else if ( $GLOBALS['SHOW_BINARY_DATA_TEXT'] == TRUE) + { + // User has requested to see the binary data as is + // Add the value as is + $output_str .= "( " . strlen( $Exif_Tag['Data'] ) . " bytes of binary data ): " . $Exif_Tag['Data'] ; + } + else + { + // User has NOT requested to see binary data, + // Add a message indicating the number of bytes to the output + $output_str .= "( " . strlen( $Exif_Tag['Data'] ) . " bytes of binary data ) " ; + } + break; + + default : + // Error - Unknown IFD datatype + $output_str .= "Error - Exif tag data type (" . $Exif_Tag['Data Type'] .") is invalid"; + break; + } +} + + // Return the resulting text string + return $output_str; +} + +/****************************************************************************** +* End of Function: get_IFD_value_as_text +******************************************************************************/ + + + + +/****************************************************************************** +* Global Variable: IFD_Data_Sizes +* +* Contents: The sizes (in bytes) of each EXIF IFD Datatype, indexed by +* their datatype number +* +******************************************************************************/ + +$GLOBALS['IFD_Data_Sizes'] = array( 1 => 1, // Unsigned Byte + 2 => 1, // ASCII String + 3 => 2, // Unsigned Short + 4 => 4, // Unsigned Long + 5 => 8, // Unsigned Rational + 6 => 1, // Signed Byte + 7 => 1, // Undefined + 8 => 2, // Signed Short + 9 => 4, // Signed Long + 10 => 8, // Signed Rational + 11 => 4, // Float + 12 => 8 ); // Double + +/****************************************************************************** +* End of Global Variable: IFD_Data_Sizes +******************************************************************************/ + + + + + + +?> |