[Ffmpeg-devel] Wrap --- again..

[Ignazio Castrogiovanni]

I've followed your suggestion to use dlopen - dlsym - dlclose to call many
times the main of ffmpeg.
Now I can make my own wrapper library that has different functions all
calling the main of ffmpeg with different parameters. Now I'm getting crazy
around a problem that I can't understand.
I have renamed the main of ffmpeg.c to boss(int argc, char **argv) and I
call it from another function (for example get_video_segment()).
Why if I call the function boss and I pass it the right parameters it works
and if I pass the same parameters to the function called by dlsym I get
Must supply at least one output file.
Here there is my code:

 void get_video_segment(int n, int m)
{
int (*principale)(int argc, char **argv); void* lib_handle;
lib_handle = dlopen("libffmpeg.so",RTLD_LAZY);*if*(!lib_handle)
{
fprintf(stderr,"Coudn't open library libffmpeg.so because os %s", dlerror());
exit(1);
}**
*(void **)(&principale) = dlsym (lib_handle,"boss");
int hl = m-n;char beg[10];char howlong[10];
sprintf(beg,"%d",n);
sprintf(howlong,"%d",hl);
parametri[0]="Yasw";
parametri[1]="-ss";
parametri[2]=beg;
parametri[3]="-t";
parametri[4]=howlong;
parametri[5]="-an";
parametri[6]="-y";
parametri[7]="-i";
parametri[8]=filein;
parametri[9]=fileout;


nParametri = 10;
*//boss(nParametri,parametri);*
int ab = (*principale)(nParametri,parametri);

dlclose(lib_handle);
}

It seems that i forget to pass the last parameter... but the same parameters
are totally working if I uncomment boss(nParametri,parametri);, and comment
the rest.

Here there is the complete output:

Seems stream 0 codec frame rate differs from container frame rate:
23.98(65535/2733) ->
23.98 (24000/1001)
Input #0, avi, from '/users/castrogiovanni/salt/salt.avi':
  Duration: 00:42:39.6, start: 0.000000, bitrate: 1192 kb/s
  Stream #0.0: Video: mpeg4, yuv420p, 624x352, 23.98 fps(r)
  Stream #0.1: Audio: mp3, 48000 Hz, stereo, 160 kb/s
Must supply at least one output file
Premi Invio per continuare!

Thanks in advance