[FFmpeg-devel] Third opinion? (was: lavf/avio: remove support for proto, , opt, val, , syntax.)

[Andreas Rheinhardt]

Nicolas George:
> Nicolas George (12021-07-30):
>> Andreas Rheinhardt (12021-07-29):
>>> The latter statement is not true: This is public API; anyone can have
>>> used it for any purpose. Your 2/5 adds a replacement for using it with
>>> dvd2concat, but there are other usages, too; e.g. concatenating several
>>> subfile files (each with its own start and end) with the concat protocol
>>> won't be possible any more with this patch.
>>
>> This feature was never documented, and only incidentally mentioned in
>> the examples for subfile, so I consider it is more akin to avpriv than
>> to a public API.
>>
>> Do you have practical examples where concatenating subfiles is useful?
> 
> This feature makes several parts of the code harder to understand, see
> hls.c and dashdec.c.
> 

I do not really get that: The option passing syntax is restricted to the
subfile protocol, so I don't know why we allow it for the file protocol
in dashdec and hls. Unless I am missing something, this could (and
should) be removed at once.

> I have also asked on the users mailing-lists:
> 
> https://ffmpeg.org/pipermail/ffmpeg-user/2021-August/date.html
> http://ffmpeg.org/pipermail/libav-user/2021-August/012836.html
> 
> Unless somebody uses it in the real world, I would favor just getting
> rid of it.
> 
I use it to concatenate parts of files: When a DVR of mine has to split
files due to the 4GB FAT-32 boundary, it does not do so cleanly; for
some reason the first 96256B of the second file are duplicated, i.e.
they coincide with bytes 96256-192511. For the third file, about a MB
starting from offset 96256 is duplicated.

- Andreas