Channel Audio from .mp4?

I am at a loss here after searching around with no results.

I am attempting to channel the audio specifically from an .mp4 for use in a driver.

I开发者_开发知识库 am aware that there are programs which extract the audio from .mp4's, but I am looking for another approach without using external applications such as those.. is there any direction that someone can point me towards to solve this problem?

Thanks,

-K

The open source library libavcodec, which is part of ffmpeg has the capability to do what you are looking for. The source is available at link text.