[FFmpeg-devel] [PATCH] avfilter: add audio surround upmixer

[Carl Eugen Hoyos]

2017-05-25 16:45 GMT+02:00 Paul B Mahol <onemda at gmail.com>:

> + at section surround
> +Apply audio surround upmix filter.
> +
> +This filter allows to produce multichannel output from
> stereo audio stream.

Does this work on Pro Logic-encoded files (ticket #4085)
or does this filter use a different algorithm?
Does a filter have advantages over an implementation in
libswresample?

Iirc, our Pro Logic downmixer has an issue with "phase shift"
(ticket 3455 / 4175): Does this filter give expected output
for FFmpeg-encoded files or original Pro Logic files (or is
there no difference on upmixing)?

Thank you, I believe this is a very important feature,
Carl Eugen