Whenever I deal with this, I have to look at the code to make sense of
this. And beyond that, there are some strange inconsistencies. (I think
this code is cursed. It always was, and maybe always will be.)
Although the manpage claimed that using multiple items for -add etc. is
deprecated, string list options didn't warn against it. So add the
warning, and add something in the changelog (even though nobody will
ever read this).
The manpage mentioned --vf-append, but this didn't even exist. So add
it, I guess. We encourage using -append for the other option types, so
for consistency, it should work on filter options. (And I already
tricked me into believing it existed when I mentioned it in the
manpage.)
Make the "operations" table separate for all option types, and mention
the option type on every single of the top-level list options.
With the internal change from stringlist to keyvaluelist, these
sub-options stop working. I don't really care enough to bring them
back. (Order doesn't matter, -del always seemed annoying.)
The main change is that we wait with opening the muxer ("writing
headers") until we have data from all streams. This fixes race
conditions at init due to broken assumptions in the old code.
This also changes a lot of other stuff. I found and fixed a few API
violations (often things for which better mechanisms were invented, and
the old ones are not valid anymore). I try to get away from the public
mutex and shared fields in encode_lavc_context. For now it's still
needed for some timestamp-related fields, but most are gone. It also
removes some bad code duplication between audio and video paths.
This commit introduces a new --oset-metadata key-value-list option,
allowing the user to specify output metadata when encoding
(eg. --oset-metadata=title="Hello",comment="World").
A second option --oremove-metadata is added to exclude existing metadata
from the output file (assuming --ocopy-metadata is enabled).
Not all output formats support all tags, but luckily libavcodec
simply discards unsupported keys.
--copy-metadata describes the result of the option better, (copying metadata
from the source file to the output file). Marks the old --no-ometadata
OPT_REMOVED with a suggestion for the new --no-ocopy-metadata.
Dave
wm4
TheAMM
Martin Herkt
c_14