For linguistic annotation of structured text documents, FLAT might be an option (https://github.com/proycon/flat); assuming you find a way of translating your documents to the FoLiA XML format (https://proycon.github.io/folia), which the annotation tool is designed for. The format specifically allows for document structure, including tables, and supports various types of linguistic annotation. It is, however, a solution that stores document and annotations together in a single integrated representation (so no separate stand-off file).
Regards,
--
Maarten van Gompel
Centre for Language Studies
Radboud Universiteit Nijmegen
proycon at anaproy.nl https://proycon.anaproy.nl https://github.com/proycon
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Quoting Nikola Milosevic (2017-05-22 13:01:36)
> Hello,
>
> I was wondering do anyone knows of any schema that allows annotation of XML
> documents with stand-off annotations and maybe tool that allows it?
> Particularly I would need something like that for annotating tables, and it
> should save somehow structure. I was working on some proposal that uses
> XPath to save the structure and location (can be seen here:
> https://gist.github.com/nikolamilosevic86/c94382d4b52705e9ae75dab0eda6381e).
> Does anyone know of anything similar?
>
>
> Best regards,
>
> Nikola Milošević
>