mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-23 12:43:46 +02:00
Since there have been quite a few questions recently on how to use the
FFmpeg libraries with Visual C++, here's a patch for the documentation that explains everything in (excruciating) detail. patch by Martin Boehme <boehme -- at -- inb -- dot -- uni-luebeck -- dot -- de> Originally committed as revision 4620 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
parent
515875484b
commit
be0efc0cfa
@ -160,8 +160,8 @@ related to the compiler.
|
||||
|
||||
Yes, but the MinGW tools @emph{must} be used to compile FFmpeg. You
|
||||
can link the resulting DLLs with any other Windows program. Read the
|
||||
@emph{Native Windows Compilation} section in the FFmpeg documentation
|
||||
to find more information.
|
||||
@emph{Native Windows Compilation} and @emph{Visual C++ compatibility}
|
||||
sections in the FFmpeg documentation to find more information.
|
||||
|
||||
@section Can you add automake, libtool or autoconf support ?
|
||||
|
||||
@ -201,6 +201,7 @@ the compilation failure then you are probably not qualified for this.
|
||||
You need a C compiler (Visual C++ is not compliant to the C standard).
|
||||
If you wish - for whatever weird reason - to use Visual C++ for your
|
||||
project then you can link the Visual C++ code with libav* as long as
|
||||
you compile the latter with a working C compiler.
|
||||
you compile the latter with a working C compiler. For more information, see
|
||||
the @emph{Visual C++ compatibility} section in the FFmpeg documentation.
|
||||
|
||||
@bye
|
||||
|
@ -918,10 +918,134 @@ headers in @file{Program Files/FFmpeg}.
|
||||
when configuring FFmpeg, FFmpeg tries to use the Microsoft Visual
|
||||
C++ @code{lib} tool to build @code{avcodec.lib} and
|
||||
@code{avformat.lib}. With these libraries you can link your Visual C++
|
||||
code directly with the FFmpeg DLLs.
|
||||
code directly with the FFmpeg DLLs (see below).
|
||||
|
||||
@end itemize
|
||||
|
||||
@subsection Visual C++ compatibility
|
||||
|
||||
FFmpeg will not compile under Visual C++ -- and it has too many
|
||||
dependencies on the GCC compiler to make a port viable. However,
|
||||
if you want to use the FFmpeg libraries in your own applications,
|
||||
you can still compile those applications using Visual C++. An
|
||||
important restriction to this is that you have to use the
|
||||
dynamically linked versions of the FFmpeg libraries (i.e. the
|
||||
DLLs), and you have to make sure that Visual-C++-compatible
|
||||
import libraries are created during the FFmpeg build process.
|
||||
|
||||
This description of how to use the FFmpeg libraries with Visual C++ is
|
||||
based on Visual C++ 2005 Express Edition Beta 2. If you have a different
|
||||
version, you might have to modify the procedures slightly.
|
||||
|
||||
Here are the step-by-step instructions for building the FFmpeg libraries
|
||||
so they can be used with Visual C++:
|
||||
|
||||
@enumerate
|
||||
|
||||
@item Install Visual C++ (if you haven't done so already).
|
||||
|
||||
@item Install MinGW and MSYS as described above.
|
||||
|
||||
@item Add a call to @file{vcvars32.bat} (which sets up the environment
|
||||
variables for the Visual C++ tools) as the first line of
|
||||
@file{msys.bat}. The standard location for @file{vcvars32.bat} is
|
||||
@file{C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat},
|
||||
and the standard location for @file{msys.bat} is
|
||||
@file{C:\msys\1.0\msys.bat}. If this corresponds to your setup, add the
|
||||
following line as the first line of @file{msys.bat}:
|
||||
|
||||
@code{call "C:\Program Files\Microsoft Visual Studio 8\VC\bin\vcvars32.bat"}
|
||||
|
||||
@item Start the MSYS shell (file @file{msys.bat}) and type @code{link.exe}.
|
||||
If you get a help message with the command line options of @code{link.exe},
|
||||
this means your environment variables are set up correctly, the
|
||||
Microsoft linker is on the path and will be used by FFmpeg to
|
||||
create Visual-C++-compatible import libraries.
|
||||
|
||||
@item Extract the current version of FFmpeg (the latest release version or
|
||||
the current CVS snapshot, whichever is recommended) and change to the
|
||||
FFmpeg directory.
|
||||
|
||||
@item Type the command
|
||||
@code{./configure --enable-shared --enable-memalign-hack} to configure and,
|
||||
if that didn't produce any errors, type @code{make} to build FFmpeg.
|
||||
|
||||
@item The subdirectories @file{libavformat}, @file{libavcodec}, and
|
||||
@file{libavutil} should now contain the files @file{avformat.dll},
|
||||
@file{avformat.lib}, @file{avcodec.dll}, @file{avcodec.lib},
|
||||
@file{avutil.dll}, and @file{avutil.lib}, respectively. Copy the three
|
||||
DLLs to your System32 directory (typically @file{C:\Windows\System32}).
|
||||
|
||||
@end enumerate
|
||||
|
||||
And here is how to use these libraries with Visual C++:
|
||||
|
||||
@enumerate
|
||||
|
||||
@item Create a new console application ("File / New / Project") and then
|
||||
select "Win32 Console Application". On the appropriate page of the
|
||||
Application Wizard, uncheck the "Precompiled headers" option.
|
||||
|
||||
@item Write the source code for your application, or, for testing, just
|
||||
copy the code from an existing sample application into the source file
|
||||
that Visual C++ has already created for you. (Note that your source
|
||||
filehas to have a @code{.cpp} extension; otherwise, Visual C++ won't
|
||||
compile the FFmpeg headers correctly because in C mode, it doesn't
|
||||
recognize the @code{inline} keyword.) For example, you can copy
|
||||
@file{output_example.c} from the FFmpeg distribution (but you will
|
||||
have to make minor modifications so the code will compile under
|
||||
C++, see below).
|
||||
|
||||
@item Open the "Project / Properties" dialog box. In the "Configuration"
|
||||
combo box, select "All Configurations" so that the changes you make will
|
||||
affect both debug and release builds. In the tree view on the left hand
|
||||
side, select "C/C++ / General", then edit the "Additional Include
|
||||
Directories" setting to contain the complete paths to the
|
||||
@file{libavformat}, @file{libavcodec}, and @file{libavutil}
|
||||
subdirectories of your FFmpeg directory. Note that the directories have
|
||||
to be separated using semicolons. Now select "Linker / General" from the
|
||||
tree view and edit the "Additional Library Directories" setting to
|
||||
contain the same three directories.
|
||||
|
||||
@item Still in the "Project / Properties" dialog box, select "Linker / Input"
|
||||
from the tree view, then add the files @file{avformat.lib},
|
||||
@file{avcodec.lib}, and @file{avutil.lib} to the end of the "Additional
|
||||
Dependencies". Note that the names of the libraries have to be separated
|
||||
using spaces.
|
||||
|
||||
@item Now, select "C/C++ / Preprocessor" from the tree view. Select "Debug"
|
||||
in the "Configuration" combo box. Add @code{EMULATE_INTTYPES} to the
|
||||
"Preprocessor Definitions". (Note that the various preprocessor
|
||||
definitions have to be separated using semicolons.) Select "Release" in
|
||||
the "Configuration" combo box and, again, add @code{EMULATE_INTTYPES} to
|
||||
the "Preprocessor Definitions". (This has to be done separately because
|
||||
debug and release builds have different preprocessor definitions.)
|
||||
Finally, select "C/C++ / Code Generation" from the tree view. Select
|
||||
"Debug" in the "Configuration" combo box. Make sure that "Runtime
|
||||
Library" is set to "Multi-threaded Debug DLL". Then, select "Release" in
|
||||
the "Configuration" combo box and make sure that "Runtime Library" is
|
||||
set to "Multi-threaded DLL".
|
||||
|
||||
@item Click "OK" to close the "Project / Properties" dialog box and build
|
||||
the application. Hopefully, it should compile and run cleanly. If you
|
||||
used @file{output_example.c} as your sample application, you will get a
|
||||
few compiler errors, but they are easy to fix. The first type of error
|
||||
occurs because Visual C++ doesn't allow an @code{int} to be converted to
|
||||
an @code{enum} without a cast. To solve the problem, insert the required
|
||||
casts (this error occurs once for a @code{CodecID} and once for a
|
||||
@code{CodecType}). The second type of error occurs because C++ requires
|
||||
the return value of @code{malloc} to be cast to the exact type of the
|
||||
pointer it is being assigned to. Visual C++ will complain that, for
|
||||
example, @code{(void *)} is being assigned to @code{(uint8_t *)} without
|
||||
an explicit cast. So insert an explicit cast in these places to silence
|
||||
the compiler. The third type of error occurs because the @code{snprintf}
|
||||
library function is called @code{_snprintf} under Visual C++. So just
|
||||
add an underscore to fix the problem. With these changes,
|
||||
@file{output_example.c} should compile under Visual C++, and the
|
||||
resulting executable should produce valid video files.
|
||||
|
||||
@end enumerate
|
||||
|
||||
@subsection Cross compilation for Windows with Linux
|
||||
|
||||
You must use the MinGW cross compilation tools available at
|
||||
|
Loading…
Reference in New Issue
Block a user