[FFmpeg-user] Seeking backward into live stream

[Patrice Briand]

Hi everyone, 

I am trying to clip a part of a live stream (HLS).
To do so, I set the position of the stream to a negative value, e.g. -10 sec and a duration of 10sec.
Unfortunately, ffmpeg never goes back to the requested position, it always start from the live time.
I also tried setting the position before the input but it fails as well.

Any one would know how to do that ?
Or may be is there any known issue regarding the negative seeking of a live stream ?

Here is the command:  ffmpeg -i input.m3u8 -c copy -ss -10 -t 10 -f mp4 output.mp4

Thank you in advance for your help.

Patrice.