R: R: R: [GRASS-dev] GRASS FFMPEG support

[marco.pasetti at alice.it]

Hi Glynn,
 
>I know building GRASS on Windows is slower than Linux, but that's
>crazy. On my Linux system, it takes around 4 minutes:
 
Consider that I'm on an Intel Core2 Duo 2.5GHz (T9300, with 6MB of L2 cache!) with 4Gb of RAM DDR2 (even if Vista actually uses only 3)!
When compiling the processors don't run at full speed, while on my old machine (AMD Athlon64 3000+, 1.8Gh and 1.25GB RAM DDR) the CPU ran at full throttle for 3 hours, with the fan sounding like a Boeing taking off! The whole MSYS environment + GRASS compiling took more than 10 hours with the CPU at its 100%...
 
>When posting error messages, please include the command which
>generated the error.
 
Sorry, I thought it was clear that it was simply the make command
 
>However, as OGSF uses av_free directly, configure should really be
>testing explicitly for libavutil. It isn't necessary on Linux, but
>Windows handles DLLs differently.
 
mmm... probably I need to make things more clear than they actually are now for me!
avutil.dll is in the same place where the other ffmpegs DLLs are!
but there's another thing that I don't undestand: when I create a ddl with gcc on MinGW I usually do as follows:

gcc -shared -s -o libname.dll -Wl,--out-implib,libname.a  $LIBOBJECTS

where libname.dll and libname.a are usually installed in /usr/local/bin and /usr/local/lib respectively; and when I create an executable that uses that library I do:

gcc -s -g -O2 -o exename.exe $EXEOBJECTS -L./ -lname
 
I'm mainly referring to those articles:
http://www.mingw.org/docs.shtml#compilingandbuilding
http://gcc.gnu.org/onlinedocs/gcc/Link-Options.html#Link-Options

The strange thing is that there are no *.a import library files created by FFMPEG, while I always have them for each library I compiled!
Last thing: the FFMPEG make script installed the DLLs in /ffmpeg/bin, while the /ffmpeg/lib dir is empty, except for the pkgconfig folder, that contains the libav*.pc files; I googled for them, but I didn't find relevant information on what they exaclty are. Do you know some useful articles about that, please?
 
Thanks for your help,
 
Marco
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.osgeo.org/pipermail/grass-dev/attachments/20080613/531d8058/attachment.html