Hi,

I am trying to attach two multimedia filters i.e., ogg decoder with audio writer filter which come as part of sample 
filters in QNX 6.3.2.

below is the code snippet..

#include <stdio.h>
#include <mmedia/mmedia.h>
#include <mmedia/mmconvenience.h>
#include <aoi/aoi.h>

int main(int argc,char *argv[])
{
    MmGraph_t *graph;
    MmFilter_t *rf,*mpf,*xf,*af, *mdf;
    MmChannel_t *rc,*mpic,*mpoc,*xic,*xoc,*ac,*mdic,*mdoc;
    int ret;
    


    MmInitialize(NULL);
    printf(" MM lib is initialized\n");
    graph=MmCreateGraph("mp3 player");


    printf(" Finding ogg decoder\n");
    if (!(mdf=MmFindFilter(graph,"ogg_decoder")))
    {
     printf("Couldn't grab the ogg decoder.\n");
     MmDestroyGraph(graph);
     exit(-5);
    }
    
    // grab the mp3_decoder filter output channel
    if (!(mdoc=MmAcquireOutputChannel(mdf,MEDIA_TYPE_AUDIO)))
    {
     printf("Couldn't get a audio output channel from mp3_dec
     MmDestroyGraph(graph);
     exit(-10);
     }

      printf("Finding Audio writer \n");

     // grab the audio_writer filter
     if (!(af=MmFindFilter(graph,"audio_writer")))
    {
     printf("Couldn't grab the audio_writer filter.\n");
     MmDestroyGraph(graph);
     exit(-11);
    }
    printf("Audio writer found\n");
    printf("Acquiring Writer's I/P channel\n");
    // grab the audio input channel
    if (!(ac=MmAcquireInputChannel(af,MEDIA_TYPE_AUDIO)))
    {
      printf("Couldn't get an audio input channel from audio_writer.\n");
      MmDestroyGraph(graph);
      exit(-12);
    }
    printf("Writer's I/P channel acquired\n");

    printf("Attaching channels : (Decoder->Writer)\n");
    if (MmAttachChannels(mdoc,ac)!=0)
   {
     printf("Couldn't attach mp3_decoder and audio_writer channels.\n");
     MmDestroyGraph(graph);
     exit(-13);
   }
   printf("Attaching channels Done : (Decoder->Writer)\n");
  return 0;
}


Please help me understand where I am doing wrong.

Thanks in advance,

Satish