This is a technical question about InDesign/PDF XMP metadata.
I'm trying to build a simple document indexer in PHP, making use of XMP information in the files indexed; i.e. PDF:s exported from InDesign.
When exporting from InDesign to PDF, information entered in the File → File Info dialog box shows up nicely in the exported PDF as XMP metadata; e.g. the title, author and description. In the old CS3, a thumbnail was included as well in
rdf:Description/xap:Thumbnails/rdf:Alt/rdf:li/xapGImg:image. However, this feature seems completely gone in CS6 (possibly in earlier versions above CS3 as well).
The InDesign file itself for sure contains page thumbnails in
rdf:Description/xmp:PageInfo/rdf:Seq/rdf:li/xmpGImg:image, but this information is nowhere to be found in the exported PDF. I've tried changing numerous settings in InDesign to get those thumbnails exported to PDF, without luck.
My question is: does anyone of you know a way to get thumbnail(s) exported to the PDF XMP metadata?