The copy
-c:v copy
(for copying the video codec) should be fine and cause no problems. The problem is because of the MP4 to MPEG-TS format translation, you also need
-bsf:v h264_mp4toannexb
in there as well.
So, something like:
pipe://ffmpeg -i sample.mp4 -c copy -bsf:v h264_mp4toannexb -f mpegts pipe:1
(A note about the
-tune zerolatency
that I see all over
ffmpeg
command lines in the TVH forums:
-tune
is for passing parameters to libx264. If you have not specified
-c:v libx264
or @-vcodec libx264@, the option is pointless and does nothing. In this example, since you are not actually encoding anything, it serves no use.)