avformat/segafilm: use av_freep()

Signed-off-by: Paul B Mahol <onemda@gmail.com>
avformat/segafilm: remove deplanarization hack

Signed-off-by: Paul B Mahol <onemda@gmail.com>
avfilter: add adelay filter

Signed-off-by: Paul B Mahol <onemda@gmail.com>
doc/formats: Add documentation for 3 parameters that have been missing

Signed-off-by: Timothy Gu <timothygu99@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>