ALTO Technical Metadata for Layout and Text Objects

Using ALTO with METS

ALTO was created for usage with METS. While using METS to wrap ALTO instances is not a requirement, most implementers have chosen to utilize ALTO inside of a METS wrapper. In order to do so, references can be made within the METS <area> element that is used within the METS <structMap>.

Screenshot of a METS area element

The FILEID attribute on <area> refers to the following structure within the METS <fileGrp> element under <fileSec>:

Screenshot of a METS fileGrp element

The BEGIN attribute on <area> then points into the ALTO file itself within one of the children of the METS <amdSec>.