[MPlayer-users] seeking in mpeg files

[Thilo Staebler]

hi!
I read a lot about seeking in mpeg-files captured from mpeg-encoder 
cards (e.g. wintv pvr 250), but everyone says something different :-(
my problem is, playback with mplayer is fine, but when I want to extract 
a picture (e.g. .png) every second with mplayer (lets say video is 45 
sec) I only get ~18 pics (cutting with mencoder also doesn't seek to the 
right position)!
Is this due to VBR and incorrect seeking? Or are the mpeg timestamps 
corrupt? is there a workaround? Or am I just missing something *g*?

thanks in advance
thilo