Note to the METS list from Carl Fleischhauer and the audio-visual project
team at the Library of Congress, January 27, 2002.
We have been hashing over the re-design of the relational database from
which we propose to generate METS documents. In the course of this, we
found ourselves in need of help re: the primary schema and the "area"
element (which appears back to back with "sequence"). I won't try to say
this in XML-speak (I am XML illiterate) but will do my best to express the
question in lay language.
The _seq_ element is defined as "should be used to link a div to a set of
content files when those files should be played sequentially to display
content to a user. Individual area subelements within the seq element
provide the links to the files or portions thereof." This seems to be
about a group of files, understood to come one after the other.
The _area_ element is defined as providing "more sophisticated linking
between a div element and content files representing that div, be they
text, image, audio, or video files. An area element can link a div to a
point within a file, to a one-dimension segment of a file (e.g., text
screen, image line, audio/video clip), or a two-dimensional section of a
file (e.g, subsection of an image, or a subsection of the video display
of a video file." This seems to be about "inside one file" and NOT about
a group of separate files.
We worry that this leaves "orphaned" a scanning phenomenon we encountered
in American Memory: "the billboard job." For very large posters, for
example, we sometimes made several rows of images, representing tiles of
the oversized original. In a perfect display system, these would come up
in a grid:
image.a1 image.a2 image.a3
image.b1 image.b2 image.b3
image.c1 image.c2 image.c3
Question: can we use the "area" elements to do this, or is there another
trick we didn't notice? If not, perhaps this is a METS version-two
Thanks for the advice! Carl