[Flac] Room for safe opaque blocks in flac streams? Looking to add error correction to flac.

[Gregory Maxwell]

Is there an obvious safe way to add some extra data to a flac file
that spec decoders will happily ignore?

I'd like to explore creating a tool which will add N extra redundancy
frames at the end which will allow perfect decoding with up to ~N
frames lost in the files. This would allow users to sacrifice a tiny
amount of compression for a substantial increase in file robustness.

This would also create a new potential audience for Flac: people who
don't care about file size but care substantially about file
robustness. A typical flac bloated back to the original wav size could
lose roughly half its blocks and still remain perfectly decodable.

http://planete-bcast.inrialpes.fr/article.php3?id_article=7 has a nice
high performance error correcting library which would work well for
this sort of application.