[FFmpeg-user] m3u8 seeking issues

[Louis Letourneau]

I'm a bit confused on what is expected when seeking with ffmpeg on m3u8
files.

I was trying to get frame 43 from a m3u8. I converted the frame to time in
seconds and when I extract that frame, the frame that I get is WAY off.
about 10 seconds off.

I did some tests and:
FFMPEG 3.1.1 with ss 0
ffmpeg -y -loglevel error -ss 00:00:00 -vsync 0 -i 2708-1.m3u8 -f image2
-q:v 1 -vframes 1  dude.png ; feh dude.png

The frame given is seconds off.

FFMPEG 3.1.1 without ss
ffmpeg -y -loglevel error -vsync 0 -i 2708-1.m3u8 -f image2 -q:v 1 -vframes
1  dude.png ; feh dude.png

Is the first frame

FFMPEG 3.1.3 with ss 0
ffmpeg -y -loglevel error -ss 00:00:00 -vsync 0 -i 2708-1.m3u8 -f image2
-q:v 1 -vframes 1  dude.png ; feh dude.png

Is the first frame

FFMPEG HEAD with ss 0
ffmpeg -y -loglevel error -ss 00:00:00 -vsync 0 -i 2708-1.m3u8 -f image2
-q:v 1 -vframes 1  dude.png ; feh dude.png

Is way off.

When converting the m3u8 to mp4
ffmpeg -i 2708-1.m3u8 -c copy -bsf:a aac_adtstoasc 2708-1.mp4

The problem goes away for all versions with or without -ss

Now the problem is that there is another bug in 3.1.3 about frame counting
that is fixed in HEAD and works in 3.1.1 (There was some regression x264
code was pulled in the changelog from 3.1.3 to head...)

I don't know if these 2 things are related or not, but as it stands I need
to choose which of the 2 bugs is less of an issue to me.

I can try to share the first few .ts available from the m3u8 but I was
wondering if this was a known issue as I couldn't find anything on this.

Thank you
Louis