file2-o.txt

Reference Implementation of G.711 standard and other voice codecs

#include <stdio.h>
#include <math.h>
#include "gpib-bib.h"
#include "fd9002.h"

void            main(int argc, char *argv[])
{
  /* Filter data */
  filter_channel_state channel_1, channel_2;

  /* Initializations of default values */
  channel_1.f0 = 0;
  channel_1.pregain = channel_1.postgain = 1.0;
  channel_1.channel = FD_BothChannels;
  channel_1.config = FD_Config0;
  channel_1.coupling = FD_AC_COUPLING;
  channel_1.input = FD_SINGLE;
  channel_1.mode = FD_ACTIVE;

  /* Check options */
  while (argc > 1 && argv[1][0] == '-' && strlen(argv[1]) > 1)
    if (strcmp(argv[1], "-f0") == 0)
    {
      /* Set the cut-off frequency and check valid range */
      channel_1.f0 = atof(argv[2]);
      if (channel_1.f0 > 102400)
	channel_1.f0 = 102400.0 /* Hz */ ;
      else if (channel_1.f0 < 0.1)
	channel_1.f0 = 0.1 /* Hz */ ;

      /* Update argv and argc to next argument */
      argv += 2;
      argc -= 2;
    }
    else if (strcmp(argv[1], "-gi") == 0)
    {
      /* Set the pre-gain (filter input gain) and check valid range */
      channel_1.pregain = atof(argv[2]);
      if (channel_1.pregain > 13.75)
	channel_1.pregain = 13.75;
      else if (channel_1.pregain < 1.0)
	channel_1.pregain = 1.0;

      /* Update argv and argc to next argument */
      argv += 2;
      argc -= 2;
    }
    else if (strcmp(argv[1], "-go") == 0)
    {
      /* Set the post-gain (filter output gain) and check valid range */
      channel_1.postgain = atof(argv[2]);
      if (channel_1.postgain > 13.75)
	channel_1.postgain = 13.75;
      else if (channel_1.postgain < 1.0)
	channel_1.postgain = 1.0;

      /* Update argv and argc to next argument */
      argv += 2;
      argc -= 2;
    }
    else if (strcmp(argv[1], "-c") == 0)
    {
      /* Set channel number */
      channel_1.channel = atoi(argv[2]) == 1 ?
	FD_Channel1 :
	FD_Channel2;

      /* Update argv and argc to next argument */
      argv += 2;
      argc -= 2;
    }
    else if (strcmp(argv[1], "-cfg") == 0)
    {
      /* Set configuration number */
      channel_1.config = (byte) atoi(argv[2]);

      /* Check for valid range */
      if (channel_1.config > 7 || channel_1.config < 0)
      {
	fprintf(stderr, "Bad configuration: valid range is 0..7\n");
	exit(1);
      }

      /* Update argv and argc to next argument */
      argv += 2;
      argc -= 2;
    }
    else if (strcmp(argv[1], "-ac") == 0)
    {
      /* Set coupling option */
      channel_1.coupling = FD_AC_COUPLING;

      /* Update argv and argc to next argument */
      argv++;
      argc--;
    }
    else if (strcmp(argv[1], "-dc") == 0)
    {
      /* Set coupling option */
      channel_1.coupling = FD_DC_COUPLING;

      /* Update argv and argc to next argument */
      argv++;
      argc--;
    }
    else if (strcmp(argv[1], "-sngl") == 0)
    {
      /* Set coupling option */
      channel_1.input = FD_SINGLE;

      /* Update argv and argc to next argument */
      argv++;
      argc--;
    }
    else if (strcmp(argv[1], "-diff") == 0)
    {
      /* Set coupling option */
      channel_1.input = FD_DIFFERENTIAL;

      /* Update argv and argc to next argument */
      argv++;
      argc--;
    }
    else if (strcmp(argv[1], "-act") == 0)
    {
      /* Set coupling option */
      channel_1.mode = FD_ACTIVE;

      /* Update argv and argc to next argument */
      argv++;
      argc--;
    }
    else if (strcmp(argv[1], "-byp") == 0)
    {
      /* Set coupling option */
      channel_1.mode = FD_BYPASS;

      /* Update argv and argc to next argument */
      argv++;
      argc--;
    }
    else
    {
      fprintf(stderr, "Invalid option \"%s\" in command line\n\n",
	      argv[1]);
      exit(1);
    }

  /* Read parameter for processing, if missing */
  if (channel_1.f0 == 0)
  {
    /* Get parameter only if not specified by the '-f0' option */
    printf("_Cut-off frequency [Hz]: .......... ");
    scanf("%lf", &channel_1.f0);
  }

  /* Initialize channel_2 */
  channel_2 = channel_1;

  /* Print options read */
  print_filter_state(channel_1, stdout);

  /* Initializing the filter structure */
  if (FD9002_open(&channel_1))
    exit(3);

  /* Progamming the filter */
  if (channel_1.channel == FD_BothChannels)
    FD9002_set_filter(channel_1);
  else
    FD9002_set_channel(channel_1);

  /* Read configuration of both channels */
  if (FD9002_get_filter_state(&channel_1, &channel_2))
    exit(3);

  /* Print configuration */
  print_filter_state(channel_1, stdout);
  print_filter_state(channel_2, stdout);

  /* Wait, check clip status and print */
  printf("\n Wait a second ...");
  delay(1000);
  printf("\r Config %d: Clip status is %d %s\n",
	 channel_1.config, (int) FD9002_get_clip(channel_1),
	 "(1->Chan1; 2->Chan2; 3->Both)");
}