typo
Use -preset
, not - preset
(notice the space). ffmpeg
uses -
to indicate a pipe, so your typo is being interpreted as a piped output.
pipe requires the -f
option
For users who get the same error, but actually want to output via a pipe, you have to tell ffmpeg
which muxer the pipe should use.
Do this with the -f
output option. Examples: -f mpegts
, -f nut
, -f wav
, -f matroska
. Which one to use depends on your video/audio formats and your particular use case.
You can see a list of muxers with ffmpeg -muxers
(not all muxers can be used with pipe).