install

mpeg4编解码器

             ---== REQUIREMENTS ==---



For Linux/MSVC, you'll need a fairly recent (>=0.98.35) version
of NASM. See: http://nasm.sourceforge.net/ 

Of course, you'll also need (GNU-)make and a compiler. A Perl
interpreter would be a plus, too (www.perl.com).




              ---== INSTALLATION ==---



For Unices:

> cd util;
> genmake.pl
> cd ../build/<system>-<compiler>/
> make subdir
> make tmp4

'tmp4' is a front end example for the core library.
there's also a couple of benches: 'make tests'.

For MSVC: 

  There's a build/msvc/sklmp4.dsw workspace.



            ---== FOOLING AROUND ==---


You can tweak the makefile stubs in each build/<system>-<compiler>/ 
directories. There are some flags to play with...


   ---== Dynamically loaded library under Win32 ==---



A ready-to-use project 'drv_mpg' is available in MSVC workspace. 
It will build a .dll library available as 'bin/skl_drv_mpg.dll'.



   ---== Dynamically loaded library under Unix ==---



When making 'tmp4', a static library 'lib/libskl_syst.a' is
built and used for linking. Using the command:

'make lib_so/libskl_syst.so'

will build the corresponding ready-to-use shared library.

Note : you can also type: 'make all_so' to build a
dynamic version of all the libraries. In
particular, the standalone .dll version of the video driver 
can prove being useful in itself.



          ---== Automagic dynamic loading ==---



In addition using to the 'regular' dynamic library (.dll and .so),
a built-in library loading is also supplied.

To use it, just define the macro SKL_USE_DYN_LOAD to anything
when compiling *your* code (Building the library with this flag
on has no effect).

Then, using the SKL_LOAD_DYN_SYMBOL macro will 'automagically' 
search for the .dll or .so library, open the file, and map the 
requested symbol.

This mecanism is useful for having transparent constructor
of external objects implemented in .dll; or for re-loading
a .dll at run-time.

Under Unix, don't forget to make the LD_LIBRARY_PATH env variable 
point to 'lib_so'!



          ---== Debugging ==---



If you want to build the debug version (very useful, because
of all the assert()), just use the command: "make tmp4 DEBUG=-g"
The debug version is not very slow, compared to the optimized one.

To debug the exceptions and asserts, it's convenient to put a
debugger breakpoint at the two dummy functions: Skl_Do_Assert() 
and Skl_Throw().




         ---== POTENTIAL TROUBLES ==---




If you get the following error message:

"../../util/makefile.unix:27: ../../util/makefile.all: 
No such file or directory
gmake: *** No rule to make target ../../util/makefile.all'.  Stop."

=> it's just you forgot to launch the "genmake.pl" script in /util.

If you get:

"FATAL: Can't create ./obj/tmp4.o: No such file or directory"

=> it's just you forgot to 'make subdir' in the build directory.


In last resort, there's a silly script 'setup.sh' that will try
to set everything up.