Re: tag editing

[Yoni Rabkin]

Grant Shoshin Shangreaux <grant@churls.world> writes:

> Hello all,
>
> working on getting my FSF assignment finished and looking forward to
> contributing to the project soon.

That is good to hear; thank you.

> I bumped into an issue when trying to edit tags for opus files, it
> looked like it all worked fine, saved the metadata to the cache-db, but
> there was no actual function defined to handle the opus format. so it
> was a surprise to me to find that the files i tagged no longer had the
> metadata the when i opened them in another program.
>
> i'd like to fix that silent failure,

This is a priority and would form a basis for all further tag editing
work. It would be great if you started there.

We would want that, if the tag editor is calling an executable, that a
failed process call would fail loudly.

Then we want that regardless of how the tags are being written, natively
or with an external process, that the editor would check if the tag had
indeed been updated in the file by comparing the tags in the file before
and after update. Trust, But Verify.

> but i also started digging around for a solution for writing tags to
> all formats. unfortunately, there isn't a simple tag writer included
> with the opus-tools package. you must re-encode the audio to add
> tags. so far, i've found 3 candidates

Re-encoding is a no-go.

>   1. add a shim for TagLib to write to files (beyond me at the moment)
>   2. opuscomment[1] tool (must be built from source)
>   3. audiotools package's tracktag program[2]

Packages such as audiotools are themselves abstractions to C libraries
such as libmpg123, libdvd-audio, etc. (like tinytag, which Emms calls).

We likely aren't going to ask to have any of those C libraries be linked
to Emacs on compilation, so the best scenario is indeed native reading
and writing, and that is a worthy goal.


-- 
   "Cut your own wood and it will warm you twice"