[Ffmpeg-devel] Dll's with MinGW

[lorenzk at gmx.net]

Hello,

after searching the archives, I found other people's questions on avformat,
avcodec and avutil libraries under Windows/MinGW.

I did successfully ffmpeg and the libs, but I get these files:
avcodec.dll
avcodec.dll.51
avcodec.dll.lib
avformat.dll
avformat.dll.50
avformat.dll.lib
avutil.dll
avutil.dll.49
avutil.dll.lib

The .51, .50, .49 files are binary identical to the .dll files.

avcodec.dll references (uses) avutil.dll.49.
avformat.dll references (uses) avutil.dll.49 and avcodec.dll.51.

Is this (using the .51, .50, .49 files) by intention?

When I look inside the lib files (with dumpbin.exe), I can see that there
are no public symbols exported, besides the standard ones:
__IMPORT_DESCRIPTOR_avcodec.dll (to me it looks like the ".dll" is wrong,
because we then need a DLL avcodec.dll.dll)
__NULL_IMPORT_DESCRIPTOR
?avcodec.dll_NULL_THUNK_DATA (again ".dll" that shouldn't be here)

So it is no wonder that the libs cannot be used to automatically link
against the DLLs.

Please could somebody with insight shed a little light on this.

Cheers
Lorenz