getSchema's RDFa Lite extractor is a REST web service to extract RDF [1] data from RDFa Lite [2] annotations and provide the semantic information as N-Triples [5] , N3 [3] and JSON [4].
This specification defines the HTML microdata mechanism. This mechanism allows machine-readable data to be embedded in HTML documents in an easy-to-write manner, with an unambiguous parsing model. It is compatible with numerous other data formats including RDF and JSON.
Christian Bizer, Kai Eckert, Robert Meusel1, Hannes Mühleisen, Michael Schuhmacher1, and Johanna Völker1
Deployment of RDFa, Microdata, and Microformats on
the Web – A Quantitative Analysis
Linked Data in Use Track - ISWC 2013
This site is a complementary effort by people from the Linked Data community to support Schema.org deployment and usage with a special focus on Linked Data:
Anything To Triples (any23) is a library, a web service and a command line tool that extracts structured data in RDF format from a variety of Web documents.
RDF Translator is a multi-format conversion tool for structured markup. It provides translations between data formats ranging from RDF/XML to RDFa or Microdata. The service allows for conversions triggered either by URI or by direct text input. Furthermore it comes with a straightforward REST API for developers.