[FFmpeg-user] which blur filter should I use?

[Lingyuan Wang]

Hi,

I'd like to downscale my video, 2160p to 1080p for example, which
pre-bluring filter should I use?  I understand ffmepg provides boxblur
and smartblur.  I looked into the source code but I couldn't tell
which algorithm smartblur uses.  The other options would be using
cvSmooth-gaussian/median/bilateral provided by libopencv (which is not
enabled by default).

Thanks.