Command Line Parser for Metadata Extraction

[Nick Burch]

Hi All

I'm currently pondering trying to add support for using ffmpeg to provide 
metadata on video (and audio) files. This would be useful for me for the 
file formats which we don't currently support, which is generally the ones 
where there's no handy Java library to call for them.

At the moment, it looks like we do have some command line support, in the 
form of ExternalParser, but that's focused only on the text extraction 
part. It also looks like it might want a few tweaks to make it easier to 
use.

I was therefore thinking of doing some work to improve it, and then adding 
in metadata too (likely via regexps or similar). One thought was to make 
it possible to use ExternalParser in two ways. The first way would be to 
subclass it and provide the mime type, command, and metadata regexps. The 
other would be to provide an xml config file, which'd supply the details. 
Likely with both of these we'd want the parser to check for the external 
command, and claim not to be available if the command isn't there.

Anyone got any thoughts on this sort of thing? Anyone done something like 
it before?

Nick