Photo2Graph Metadata

JPEG Photos have 5 different types of Metadata:

Exif – Exchangable Interchange Format – this is the most basic set of metadata
IPTC -IMM (pre-XMP) – IPTC metadata is split into the legacy IPTC-IMM section and IPTC within XMP (see below)
JPEG Comments – this is a separate section of metadata allowing multiple comments to be added – these are
XMP – the Extensible Metadata Platform (XMP) includes the IPTC-IMM metadata and many new metadata. Metadata software should keep the XMP and non-XMP IPTC properties aligned although in many cases they are not.
System Data (this is system dependent e.g. but includes system file properties such as File Size, Date Created – some Windows metadata is not visible from Linux, for instance)

There is quite a bit of overlap – for instance, the Location information (such as “City”) can be present in IPTC-IMM, and three places in XMP (Location (Legacy). LocationCreated and LocationShown and XMP (in up to 3 Locations) – so potentially in 4 Locations.
Most software programs will automatically put important descriptive metadata (e.g.Date Created, Description) into the XMP section – so XMP should be a fairly complete
collection of metadata that can be used as a search resource. For instance, all Adobe products copy information into XMP. Photo2Graph will ensure that metadata is consistent across the
the various possible fields – see the Metadata Page for information.