Linux Which MPEG2 c libraries to use?

Hi to all,
I'm very new to linux and I have been assigned a project: write a command line linux program in c which will read a mpeg2 video file and output the first n secs, also in mpeg2 format. I'm googling for libraries to use and I've come up with libmpeg3, ffmpeg, mjpeg. Since I'm new to the whole linux programming idea, I cannot really judge which one I should use as a base for writing my program, and if there is something even better that I haven't find.

Please help a newbie! Which should I use?

 

i dont know much about the programming aspect but a lot of players seem to use ffmpeg