Proposal for SMDL compliance in MPEG7, ISO/IEC JTC/SC29/WG11/P620 Lancaster, MPEG, 1999. Lancaster, Motion Picture Expert Group.

This proposal-discussion takes on board discussions held at the AdHoc Evaluation
Meeting in Lancaster including Pre-proposals P620 ("Structured time-based event") and
P622 ("music event") and the evaluated proposals P155 ("Sonata Forms Description
Scheme") and P154/169/163/170 ("Structured and unstructured links") and document
M3649 ("Some remarks on Document Structure and Description Schemes").
Due to the need to create a generic method of specifying and describing music content,
this document proposes a set of DS and D to provide a general way of describing music
content. It is closely based on an existent standard SMDL1 in order to maximize
compatibility in the future.

This set of Description Schemes and its associated set of Descriptors describe a
structured time-based entity (or musical note or musical entity or audio entity) in its
relation to other internal or external structured time-based entities.

At a very low-level, a Description Scheme named "thread” can take on form (with
different Descriptors) to describe a music event down to note level (or further). These
Descriptors can take on different forms, and it is possible that additional descriptors
with different means of describing a music event exactly, can be added. Proposed in this
document are two , one describing the music entity in its abstract form with its four
"logical" characteristics: a) duration, b) p itch, c) loudness and d) other characteristics.
The second one describes musical events with SMDL syntax. Another descriptor used in
this scheme could be a link to a certain section of a structured or unstructured format.