xvid on Mac OSX

Hi,

I hope this is the right place to post this question.

I am trying to use Terminal to build and  install  
xvidcore-1.1.3.tar.gz on my Mac
running OSX 10.4.11. I have got as far as this message in the  
Terminal window:

XviD has been successfully built.

  * Binaries are currently located in the '=build' directory
  * To install them on your system, you can run '# make install'
    as root.

When I enter the command 'make install' I get the following errors:

  D: /usr/local/lib
install: chmod 755 /usr/local/lib: Operation not permitted
   I: /usr/local/lib/libxvidcore.4.dylib
install: /usr/local/lib/libxvidcore.4.dylib: Permission denied
make: *** [install] Error 71

I am new to UNIX and the Terminal, so I am not sure if I am
trying to install from the wrong directory as I don't quite
understand the following:

* To install them on your system, you can run '# make install'
    as root.

Or is it because I need an administrator password? The Terminal
did not ask for one.

If possible please try to make any replies simple.

Thanks,

Terrence