public final void setDataSource(
            FileDescriptor fd, long offset, long length) throws IOException {
        mApiExtractor.setDataSource(fd, offset, length);
    }
Sets the data source (FileDescriptor) to use.  The FileDescriptor must be
seekable (N.B. a LocalSocket is not seekable). It is the caller's responsibility
to close the file descriptor. It is safe to do so as soon as this call returns.

@param fd the FileDescriptor for the file you want to extract from.
@param offset the offset into the file where the data to be extracted starts, in bytes
@param length the length in bytes of the data to be extracted
MediaPlayer/src/main/java/net/protyposis/android/mediaplayer/MediaExtractor.java