Background: I have been attempting to read the rating that is assigned in Adobe Bridge CS3 using the creative commons Metadata toolkit for php without success. I am using shared hosting so I do not have an oppotunity to recompile php with different modules.
Is php code available that could be used to read the rating that is embedded in the .jpg file? I have read that this is an xmp (xml) formatted section within the file.
I'm posting my solution here in case someone else has a similiar problem and reads this thread. Here is what I found:
Windows Vista add the rating to the exif section embedded in the file
Adobe Bridge adds another section to the jpg file that contains data formatted in xml. The xml + data structure is referred to as the xmp file.
I hadn't yet processed the file with Adobe bridge, that is why I was unable to read the xmp data with the Metadata toolkit.
Using the Creative Commons - Metadata toolkit I was able to read the ratings using the following code. This code is part of a Drupal Module, some of the referenced variables are Drupal settings: variable_get() is a Drupal function to read a variable from a perssistent data store.
include_once("PHP_JPEG_Metadata_Toolkit_1.11/JPEG.php"); include_once("PHP_JPEG_Metadata_Toolkit_1.11/Photoshop_File_Info.php"); include_once("PHP_JPEG_Metadata_Toolkit_1.11/EXIF.php"); include_once("PHP_JPEG_Metadata_Toolkit_1.11/XMP.php"); $photodir = variable_get('rotate_images_sourcefiles_dir',"sites/default/files/imageNodes"); $rating_threshold = variable_get('rotate_images_rating_threshold',3); $allImages=dir($photodir); $filenames = scandir($photodir); foreach($filenames as $filename){ $rating = null; $info = pathinfo($filename); if (strtolower($info['extension'])=="jpg"){ // First try to get the rating from the EXIF data, this is where it is stored by Windows Vista $exif = get_EXIF_JPEG( $photodir . "/" . $filename ); $rating = $exif[0][18246]['Data'][0]; $jpeg_header = get_jpeg_header_data($photodir . "/" . $filename ); // If no rating was found in the EXIF data, it may be in the Adobe format xmp section if ($rating == null){ if($jpeg_header != false){ $xmp = get_XMP_text($jpeg_header); $xmpArray = read_XMP_array_from_text($xmp); $rating = $xmpArray[0]['children'][0]['children'][0][attributes]['xap:Rating']; } } } }
I did need to modify the EXIF_Tags.php file in the metadata toolkit by adding an additional entry to the EXIF Tags array. I reported this to the author, but I don't believe he is maintaing the module any longer. The source is on sourceforge, but I don't know how to post a patch. So you may need to make the change to EXIF.php yourself to make the code work.
'EXIF' => array ( // Exif IFD 18246 => array ( 'Name' => "Rating", 'Type' => "Numeric" ),