gstreamer/gst/passthrough/filter.func

{
  guint j;
  static long int sample = 0;	/* you can use this to count samples */

  /*
   * process data here  
   * *data contains the original 8 or 16 bit samples and is modified in place
   * channels are interleaved in input data
   */
  
  /* do nothing */
  
  for (j = 0; j < num_samples; j++) 
  {
     data[j] = data[j];
  }
  sample += num_samples;
}