[FFmpeg-devel] [PATCH][TESTERS WANTED] avfilter: add apitch filter

[Paul B Mahol]

Hi,

On 5/11/19, Nicolas George <george at nsup.org> wrote:
> Paul B Mahol (12019-05-11):
>> Signed-off-by: Paul B Mahol <onemda at gmail.com>
>> ---
>>
>> This filter can dynamically change both tempo and pitch of audio.
>> Also scale range is bigger, from 0.01 to 100.
>>
>> ---
>>  libavfilter/Makefile     |   1 +
>>  libavfilter/af_apitch.c  | 764 +++++++++++++++++++++++++++++++++++++++
>>  libavfilter/allfilters.c |   1 +
>>  3 files changed, 766 insertions(+)
>>  create mode 100644 libavfilter/af_apitch.c
>
> For usability and maintenance reasons already explained, must be part of
> atempo.

Thanks for kind and very helpful comments.

It is currently separate filter for ease of testing.
It can not be "part" of current atempo implementation for numerous reasons,
most significant one being bad output quality with < 1 tempo scale
factor of current
atempo implementation. Also current atempo implementation have limits
for minimal
scale reduction, unlike rubberband filter in libavfilter.
Also rubberband filter having similar and bigger functionality.

That's way I request for quality testers.
Best would be to compare this filter with rubberband and current atempo filter.

This filter is supposed to be current atempo full replacement.
(atempo would be just this filter but with same first two options but
with swapped positions).

>
> Also, missing doc.

Options are self-explanatory, at least first two.
Documentation will appear later.

Regards, and have a nice day.