<?php
/******************************************************************************
*
* Filename: get_minolta_thumb.php
*
* Description: This script extracts a Minolta EXIF Makernote Thumbnail
* from within a JPEG file and allows it to be displayed
*
* Usage: get_minolta_thumb?filename=<filename>
*
* Author: Evan Hunter
*
* Date: 23/7/2004
*
* Project: PHP JPEG Metadata Toolkit
*
* Revision: 1.00
*
* 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: hide@address.com
*
******************************************************************************/
// Ensure that nothing can write to the standard io, before we get the header out
ob_start( );
include 'EXIF.php';
// retrieve the filename from the URL parameters
$filename = $GLOBALS['HTTP_GET_VARS']['filename'];
// Retrieve any EXIF data in the file
$Exif_array = get_EXIF_JPEG( $filename );
// Check if any EXIF data was retrieved
if ( $Exif_array === false )
{
// No EXIF data was found - abort
ob_end_clean ( );
echo "<p>Error getting EXIF Information</p>\n";
return;
}
// Check that there is at least the Zeroth IFD in the array
if ( count( $Exif_array ) < 1 )
{
ob_end_clean ( );
echo "<p>Couldn't find TIFF IFD 0</p>\n";
return;
}
// Check that the EXIF IFD exists
if ( array_key_exists( 34665, $Exif_array[0] ) )
{
// Found the EXIF IFD,
// Check that the makernote tag exists
if ( array_key_exists( 37500, $Exif_array[0][34665]['Data'][0] ) )
{
// Makernote Exists
// Check that the Makernote is Olympus
if ( $Exif_array[0][34665]['Data'][0][37500]['Makernote Tags'] == "Olympus" )
{
// Makernote is Olympus
// Check if an IFD exists for the makernote
if ( array_key_exists( 0, $Exif_array[0][34665]['Data'][0][37500]['Decoded Data'] ) )
{
// Check if the Thumbnail tag 0x0088 exists
if ( array_key_exists( 0x0088, $Exif_array[0][34665]['Data'][0][37500]['Decoded Data'][0] ) )
{
// Found a Thumbnail
// Get the data
$data = $Exif_array[0][34665]['Data'][0][37500]['Decoded Data'][0][0x0088]['Data'];
// Sometimes the Minolta thumbnails are corrupt as there is no data
// Check that the data is OK
if ( $data !== false )
{
// Minolta thumbnails seem to have the first byte incorrect - this could possibly be a counter in case the thumbnail needs to span more than one tag
// Restore the first byte of the jpeg thumbnail
$data{0} = "\xff";
// Display the thumbnail
ob_end_clean ( );
header("Content-type: image/jpeg");
print $data;
}
else
{
// Thumbnail data is missing - display message
ob_end_clean ( );
echo "<p>Thumbnail missing</p>\n";
}
}
// Check if the Thumbnail tag 0x0081 exists
else if ( array_key_exists( 0x0081, $Exif_array[0][34665]['Data'][0][37500]['Decoded Data'][0] ) )
{
// Found a Thumbnail
// Get the data
$data = $Exif_array[0][34665]['Data'][0][37500]['Decoded Data'][0][0x0081]['Data'];
// Sometimes the Minolta thumbnails are corrupt as there is no data
// Check that the data is OK
if ( $data !== false )
{
// Minolta thumbnails seem to have the first byte incorrect - this could possibly be a counter in case the thumbnail needs to span more than one tag
// Restore the first byte of the jpeg thumbnail
$data{0} = "\xff";
// Display the thumbnail
ob_end_clean ( );
header("Content-type: image/jpeg");
print $data ;
}
else
{
// Thumbnail data is missing - display message
ob_end_clean ( );
echo "<p>Thumbnail missing</p>\n";
}
}
else
{
// Couldn't find a Minolta thumbnail tag - display message
ob_end_clean ( );
echo "<p>Couldn't find Minolta Thumbnail Tag</p>\n";
}
}
else
{
// Couldn't find an IFD in the Makernote tag - display message
ob_end_clean ( );
echo "<p>Makernote Doesn't contain IFD 0</p>\n";
}
}
else
{
// Makernote does not use Olympus tags - display message
ob_end_clean ( );
echo "<p>Not an Olympus Makernote</p>\n";
}
}
else
{
// Couldn't find Makernote tag - display message
ob_end_clean ( );
echo "<p>Couldn't find Makernote</p>\n";
}
}
else
{
// Couldn't find the EXIF IFD - display message
ob_end_clean ( );
echo "<p>Couldn't find Exif IFD</p>\n";
}
return;
?>