[FFmpeg-user] Splitting at key frames?

[Gilles]

Hello

	I need to split a 67mn FLV video (vp6f + mp3) into two parts (40mn
and the remainder starting 10s before), so used the following
commands:

(2400s = 40mn)
ffmpeg.exe -i input.flv -ss 00:00:00 -t 2400 -c:v copy -c:a copy
output1.1.of.2.flv
ffmpeg.exe -i input.flv -ss 00:39:50 -c:v copy -c:a copy
output1.2.of.2.flv

The reason for starting the second video 10s before is to make the
transition easier to follow by adding some overlap.

It mostly works but I noticed that the second video freezes for a few
seconds at the beginning: Could it be that ffmpeg doesn't split at key
frames?

FWIW...
1. I used the latest Windows ffmpeg available at this time:

ffmpeg version N-55644-g68b63a3 Copyright (c) 2000-2013 the FFmpeg
developers
built on Aug 19 2013 20:27:12 with gcc 4.7.3 (GCC)

2. The whole input file is temporarily available here:
http://dl.free.fr/j57cduLA7

Thank you.