SMIL 3.0 unofficial XSD
I still consider SMIL the best example of a near perfect data model which is described at such depth (read: complex) that it is virtually impossible to come up with solutions that implement the data model holistically.
Starting with my own playout software based on SMIL (read: open standards) I have noticed in the past years the availability "better" XSD model generators slowly start to appear beyond the scope of JAXB. xsData is a great example of such. The need for maintained schemas is therefore a requirement for a proper implementation.
Historically SMIL only has seen DTD and Relax-NG for validation purposes, but never an XSD. Conversion software between DTD and XSD has been available two decades ago and used for this effort. This repository contains a Trang converted DTD, with a manual change to place the "correct" namespace.
Regarding copyright, the original W3 copyright has been added to the repository. As per copyright mandate: the original location of the material
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