When IMatch indexes new images, it reads the embedded metadata like EXIF, GPS and IPTC and then produces a rich and complete XMP metadata record from the imported native data.
If you are new to metadata or find this topic complicated, check out Metadata for Beginners in the IMatch Help System.
XMP uses so-called namespaces to manage different types of data. There are namespaces for EXIF metadata, IPTC metadata and other metadata groups. The EXIF namespace in XMP contains copies of most of the native EXIF metadata fields (tags) written by your camera or phone. If an image contains legacy (IIM3) IPTC metadata, this data is transferred into the corresponding XMP namespaces named IPTC and IPTCExt.
If the file already has XMP metadata (embedded or in a sidecar file), IMatch imports that data and adds missing tags as needed.
IMatch also produces the important XMP metadata tags “Create Date” and “Date Subject Created” from native EXIF metadata found in the image, or from a wide range of other metadata fields when EXIF is not available – for example in video files or PDF documents. See How IMatch uses Date and Time Information for more information about this subject.
The result of this is a rich, complete and standard-compliant XMP metadata record, which encompasses the native metadata found in the image and metadata IMatch has created or updated during the import. This record is stored safely in your IMatch database, alongside cached copies of the native metadata found in the file.
If the file had no XMP metadata before or IMatch has enriched an existing XMP record, it must write that XMP record once to the file to persist it. And this is why, usually, newly indexed files in IMatch are marked for pending write-back and show the yellow write-back pen in File Windows.
Mario M. Westphal is the developer of IMatch, the digital asset management system (DAM) for Windows. He has a strong background in software development and photography, gained through working for over 30 years in the field for many clients. His special interests are photography, music. literature and of course software development, with a strong focus on digital asset management, database systems and image metadata. He hails from Germany.
