lavfi/pad: use FFSIGN

Signed-off-by: Paul B Mahol <onemda@gmail.com>
lavfi/drawutils: fix planar rgb

Signed-off-by: Paul B Mahol <onemda@gmail.com>
lavfi/rotate: switch to new drawutils

Get rid of ugly hacks, also add support for more pixel formats.

Signed-off-by: Paul B Mahol <onemda@gmail.com>
tests/fate/filter-audio: update asyncts reference

The new reference matches the one used by qatar

Fixes: fate-filter-asyncts

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>