Merge pull request #3 from drowe67/dr-cleanup21.2.0

Cleanup Part 2

1 files changed, 367 insertions, 336 deletions

diff --git a/src/ofdm_mod.c b/src/ofdm_mod.c
index 800b410..d4c495e 100644
--- a/src/ofdm_mod.c
+++ b/src/ofdm_mod.c
@@ -29,382 +29,413 @@
 
 #define OPTPARSE_IMPLEMENTATION
 #define OPTPARSE_API static
-#include "optparse.h"
-
 #include <assert.h>
+#include <math.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <math.h>
 
 #include "codec2_ofdm.h"
-#include "ofdm_internal.h"
 #include "gp_interleaver.h"
-#include "ldpc_codes.h"
 #include "interldpc.h"
+#include "ldpc_codes.h"
+#include "ofdm_internal.h"
+#include "optparse.h"
 #include "varicode.h"
 
-#define IS_DIR_SEPARATOR(c)     ((c) == '/')
+#define IS_DIR_SEPARATOR(c) ((c) == '/')
 
 static const char *progname;
 
 void opt_help() {
-    fprintf(stderr, "\nusage: %s [options]\n\n", progname);
-    fprintf(stderr, "  --in      filename    Name of InputOneCharPerBitFile\n");
-    fprintf(stderr, "  --out     filename    Name of OutputModemRawFile\n");
-    fprintf(stderr, "  --mode    modeName    Predefined mode 700D|700E|2020|2020B|datac0 ... etc\n");
-    fprintf(stderr, "  --nc      [17..62]    Number of Carriers (17 default, 62 max)\n");
-    fprintf(stderr, "  --ns       symbols    One pilot every ns symbols (8 default)\n");
-    fprintf(stderr, "  --tcp        Nsecs    Cyclic Prefix Duration (.002 default)\n");
-    fprintf(stderr, "  --ts         Nsecs    Symbol Duration (.018 default)\n");
-    fprintf(stderr, "  --testframes Nsecs    Transmit test frames for Nsec (--testframes NpacketsPerBurst in burst mode)\n");
-    fprintf(stderr, "  --tx_freq     freq    Set an optional modulation TX centre frequency (1500.0 default)\n");
-    fprintf(stderr, "  --rx_freq     freq    Set an optional modulation RX centre frequency (1500.0 default)\n\n");
-    fprintf(stderr, "  --verbose  [1|2|3]    Verbose output level to stderr (default off)\n");
-    fprintf(stderr, "  --txbpf               Transmit band pass filter on (default off)\n");
-    fprintf(stderr, "  --clip                Transmit clipper (default off)\n");
-    fprintf(stderr, "  --text                Include a standard text message boolean (default off)\n");
-    fprintf(stderr, "  -i --ldpc    [1|2]    Run LDPC decoder (1 -> (224,112) 700D code, 2 -> (504,396) 2020 code).\n"
-                    "                        In testframe mode raw and coded errors will be counted.\n");
-    fprintf(stderr, "  --bursts   nBursts    Burst mode: Send nBursts of testframes each\n");
-    fprintf(stderr, "\n");
-    exit(-1);
+  fprintf(stderr, "\nusage: %s [options]\n\n", progname);
+  fprintf(stderr, "  --in      filename    Name of InputOneCharPerBitFile\n");
+  fprintf(stderr, "  --out     filename    Name of OutputModemRawFile\n");
+  fprintf(stderr,
+          "  --mode    modeName    Predefined mode 700D|700E|2020|2020B|datac0 "
+          "... etc\n");
+  fprintf(stderr,
+          "  --nc      [17..62]    Number of Carriers (17 default, 62 max)\n");
+  fprintf(stderr,
+          "  --ns       symbols    One pilot every ns symbols (8 default)\n");
+  fprintf(stderr,
+          "  --tcp        Nsecs    Cyclic Prefix Duration (.002 default)\n");
+  fprintf(stderr, "  --ts         Nsecs    Symbol Duration (.018 default)\n");
+  fprintf(stderr,
+          "  --testframes Nsecs    Transmit test frames for Nsec (--testframes "
+          "NpacketsPerBurst in burst mode)\n");
+  fprintf(stderr,
+          "  --tx_freq     freq    Set an optional modulation TX centre "
+          "frequency (1500.0 default)\n");
+  fprintf(stderr,
+          "  --rx_freq     freq    Set an optional modulation RX centre "
+          "frequency (1500.0 default)\n\n");
+  fprintf(
+      stderr,
+      "  --verbose  [1|2|3]    Verbose output level to stderr (default off)\n");
+  fprintf(
+      stderr,
+      "  --txbpf               Transmit band pass filter on (default off)\n");
+  fprintf(stderr, "  --clip                Transmit clipper (default off)\n");
+  fprintf(stderr,
+          "  --text                Include a standard text message boolean "
+          "(default off)\n");
+  fprintf(stderr,
+          "  -i --ldpc    [1|2]    Run LDPC decoder (1 -> (224,112) 700D code, "
+          "2 -> (504,396) 2020 code).\n"
+          "                        In testframe mode raw and coded errors will "
+          "be counted.\n");
+  fprintf(
+      stderr,
+      "  --bursts   nBursts    Burst mode: Send nBursts of testframes each\n");
+  fprintf(stderr, "\n");
+  exit(-1);
 }
 
 int main(int argc, char *argv[]) {
-    char *fin_name, *fout_name;
-    int i, opt, val;
-
-    char *pn = argv[0] + strlen(argv[0]);
-
-    while (pn != argv[0] && !IS_DIR_SEPARATOR(pn[-1]))
-        --pn;
-
-    progname = pn;
-
-    /* Turn off stream buffering */
-
-    setvbuf(stdin, NULL, _IONBF, BUFSIZ);
-    setvbuf(stdout, NULL, _IONBF, BUFSIZ);
-
-    FILE *fin = stdin;
-    FILE *fout = stdout;
-
-    /* set for LDPC coded or uncoded frames */
-
-    int ldpc_en = 0;
-
-    int input_specified = 0;
-    int output_specified = 0;
-    int verbose = 0;
-    bool clip_en = false;
-    int txbpf_en = 0;
-    int testframes = 0;
-    int use_text = 0;
-
-    int Npackets = 0;
-    int Nsec = 0;
-    int burst_mode = 0;
-    int Nbursts = 1;
-    
-    /* set up the default modem config */
-    struct OFDM_CONFIG *ofdm_config = (struct OFDM_CONFIG *) calloc(1, sizeof (struct OFDM_CONFIG));
-    assert(ofdm_config != NULL);
-    char mode[32] = "700D";
-    ofdm_init_mode(mode, ofdm_config);
-
-    int   Ndatabitsperpacket = 0;
-    struct optparse options;
-
-    struct optparse_long longopts[] = {
-        {"in", 'a', OPTPARSE_REQUIRED},
-        {"out", 'b', OPTPARSE_REQUIRED},
-        {"nc", 'c', OPTPARSE_REQUIRED},
-        {"ns", 'm', OPTPARSE_REQUIRED},
-        {"tcp", 'd', OPTPARSE_REQUIRED},
-        {"ts", 'e', OPTPARSE_REQUIRED},
-        {"testframes", 'f', OPTPARSE_REQUIRED},
-        {"tx_freq", 'n', OPTPARSE_REQUIRED},
-        {"rx_freq", 'i', OPTPARSE_REQUIRED},
-        {"ldpc", 'j', OPTPARSE_NONE},
-        {"txbpf", 'k', OPTPARSE_NONE},
-        {"clip", 'r', OPTPARSE_NONE},
-        {"text", 'l', OPTPARSE_NONE},
-        {"verbose", 'v', OPTPARSE_REQUIRED},
-        {"mode", 'g', OPTPARSE_REQUIRED},
-        {"help", 'h', OPTPARSE_NONE},
-        {"bursts", 'o', OPTPARSE_REQUIRED},
-        {0, 0, 0}
-    };
-
-    optparse_init(&options, argv);
-
-    while ((opt = optparse_long(&options, longopts, NULL)) != -1) {
-        switch (opt) {
-            case '?':
-            case 'h':
-                opt_help();
-            case 'a':
-                fin_name = options.optarg;
-                input_specified = 1;
-                break;
-            case 'b':
-                fout_name = options.optarg;
-                output_specified = 1;
-                break;
-            case 'c':
-                val = atoi(options.optarg);
-
-                if (val > 62 || val < 17) {
-                    opt_help();
-                } else {
-                    ofdm_config->nc = val;
-                }
-                break;
-            case 'd':
-                ofdm_config->tcp = atof(options.optarg);
-                break;
-            case 'e':
-                ofdm_config->ts = atof(options.optarg);
-                ofdm_config->rs = 1.0f / ofdm_config->ts;
-                break;
-            case 'm':
-                ofdm_config->ns = atoi(options.optarg);
-                break;
-            case 'f':
-                testframes = 1;
-                Nsec = atoi(options.optarg);
-                break;
-            case 'g':
-                strcpy(mode, options.optarg);
-                ofdm_init_mode(mode, ofdm_config);
-                break;
-            case 'n':
-                ofdm_config->tx_centre = atof(options.optarg);
-                break;
-            case 'o':
-                burst_mode = 1;
-                Nbursts = atoi(options.optarg);
-                fprintf(stderr, "bursts: %d\n", Nbursts);
-                break;
-            case 'i':
-                ofdm_config->rx_centre = atof(options.optarg);
-                break;
-            case 'j':
-                ldpc_en = 1;
-                break;
-            case 'k':
-                txbpf_en = 1;
-                break;
-            case 'l':
-                use_text = 1;
-                break;
-            case 'r':
-                clip_en = true;
-                break;
-            case 'v':
-                verbose = atoi(options.optarg);
-                if (verbose < 0 || verbose > 3)
-                    verbose = 0;
+  char *fin_name, *fout_name;
+  int i, opt, val;
+
+  char *pn = argv[0] + strlen(argv[0]);
+
+  while (pn != argv[0] && !IS_DIR_SEPARATOR(pn[-1])) --pn;
+
+  progname = pn;
+
+  /* Turn off stream buffering */
+
+  setvbuf(stdin, NULL, _IONBF, BUFSIZ);
+  setvbuf(stdout, NULL, _IONBF, BUFSIZ);
+
+  FILE *fin = stdin;
+  FILE *fout = stdout;
+
+  /* set for LDPC coded or uncoded frames */
+
+  int ldpc_en = 0;
+
+  int input_specified = 0;
+  int output_specified = 0;
+  int verbose = 0;
+  bool clip_en = false;
+  int txbpf_en = 0;
+  int testframes = 0;
+  int use_text = 0;
+
+  int Npackets = 0;
+  int Nsec = 0;
+  int burst_mode = 0;
+  int Nbursts = 1;
+
+  /* set up the default modem config */
+  struct OFDM_CONFIG *ofdm_config =
+      (struct OFDM_CONFIG *)calloc(1, sizeof(struct OFDM_CONFIG));
+  assert(ofdm_config != NULL);
+  char mode[32] = "700D";
+  ofdm_init_mode(mode, ofdm_config);
+
+  int Ndatabitsperpacket = 0;
+  struct optparse options;
+
+  struct optparse_long longopts[] = {{"in", 'a', OPTPARSE_REQUIRED},
+                                     {"out", 'b', OPTPARSE_REQUIRED},
+                                     {"nc", 'c', OPTPARSE_REQUIRED},
+                                     {"ns", 'm', OPTPARSE_REQUIRED},
+                                     {"tcp", 'd', OPTPARSE_REQUIRED},
+                                     {"ts", 'e', OPTPARSE_REQUIRED},
+                                     {"testframes", 'f', OPTPARSE_REQUIRED},
+                                     {"tx_freq", 'n', OPTPARSE_REQUIRED},
+                                     {"rx_freq", 'i', OPTPARSE_REQUIRED},
+                                     {"ldpc", 'j', OPTPARSE_NONE},
+                                     {"txbpf", 'k', OPTPARSE_NONE},
+                                     {"clip", 'r', OPTPARSE_NONE},
+                                     {"text", 'l', OPTPARSE_NONE},
+                                     {"verbose", 'v', OPTPARSE_REQUIRED},
+                                     {"mode", 'g', OPTPARSE_REQUIRED},
+                                     {"help", 'h', OPTPARSE_NONE},
+                                     {"bursts", 'o', OPTPARSE_REQUIRED},
+                                     {0, 0, 0}};
+
+  optparse_init(&options, argv);
+
+  while ((opt = optparse_long(&options, longopts, NULL)) != -1) {
+    switch (opt) {
+      case '?':
+      case 'h':
+        opt_help();
+      case 'a':
+        fin_name = options.optarg;
+        input_specified = 1;
+        break;
+      case 'b':
+        fout_name = options.optarg;
+        output_specified = 1;
+        break;
+      case 'c':
+        val = atoi(options.optarg);
+
+        if (val > 62 || val < 17) {
+          opt_help();
+        } else {
+          ofdm_config->nc = val;
         }
+        break;
+      case 'd':
+        ofdm_config->tcp = atof(options.optarg);
+        break;
+      case 'e':
+        ofdm_config->ts = atof(options.optarg);
+        ofdm_config->rs = 1.0f / ofdm_config->ts;
+        break;
+      case 'm':
+        ofdm_config->ns = atoi(options.optarg);
+        break;
+      case 'f':
+        testframes = 1;
+        Nsec = atoi(options.optarg);
+        break;
+      case 'g':
+        strcpy(mode, options.optarg);
+        ofdm_init_mode(mode, ofdm_config);
+        break;
+      case 'n':
+        ofdm_config->tx_centre = atof(options.optarg);
+        break;
+      case 'o':
+        burst_mode = 1;
+        Nbursts = atoi(options.optarg);
+        fprintf(stderr, "bursts: %d\n", Nbursts);
+        break;
+      case 'i':
+        ofdm_config->rx_centre = atof(options.optarg);
+        break;
+      case 'j':
+        ldpc_en = 1;
+        break;
+      case 'k':
+        txbpf_en = 1;
+        break;
+      case 'l':
+        use_text = 1;
+        break;
+      case 'r':
+        clip_en = true;
+        break;
+      case 'v':
+        verbose = atoi(options.optarg);
+        if (verbose < 0 || verbose > 3) verbose = 0;
     }
+  }
 
-    /* Print remaining arguments to give user a hint */
+  /* Print remaining arguments to give user a hint */
 
-    char *arg;
+  char *arg;
 
-    while ((arg = optparse_arg(&options)))
-        fprintf(stderr, "%s\n", arg);
+  while ((arg = optparse_arg(&options))) fprintf(stderr, "%s\n", arg);
 
-    if (input_specified) {
-        if ((fin = fopen(fin_name, "rb")) == NULL) {
-            fprintf(stderr, "Error opening input bits file: %s\n", fin_name);
-            exit(-1);
-        }
+  if (input_specified) {
+    if ((fin = fopen(fin_name, "rb")) == NULL) {
+      fprintf(stderr, "Error opening input bits file: %s\n", fin_name);
+      exit(-1);
     }
+  }
 
-    if (output_specified) {
-        if ((fout = fopen(fout_name, "wb")) == NULL) {
-            fprintf(stderr, "Error opening output modem sample file: %s\n", fout_name);
-            exit(-1);
-        }
+  if (output_specified) {
+    if ((fout = fopen(fout_name, "wb")) == NULL) {
+      fprintf(stderr, "Error opening output modem sample file: %s\n",
+              fout_name);
+      exit(-1);
     }
-
-    /* init the modem with our (optionally) custom config */
-    struct OFDM *ofdm = ofdm_create(ofdm_config);
-    assert(ofdm != NULL);
-
-    free(ofdm_config);
-
-    /* Get a copy of the completed modem config (ofdm_create() fills in more parameters) */
-    ofdm_config = ofdm_get_config_param(ofdm);
-
-    /* set up some useful constants */
-
-    int Nbitsperpacket = ofdm_get_bits_per_packet(ofdm);
-    int Npayloadbitsperpacket = Nbitsperpacket - ofdm->nuwbits - ofdm->ntxtbits;
-    int Nsamperpacket = ofdm_get_samples_per_packet(ofdm);
-
-    /* Set up LPDC code */
-
-    struct LDPC ldpc;
-    if (ldpc_en) {
-        ldpc_codes_setup(&ldpc, ofdm->codename);
-        ldpc_mode_specific_setup(ofdm, &ldpc);
-        Ndatabitsperpacket = ldpc.data_bits_per_frame;
-
-        if (verbose > 1) {
-            fprintf(stderr, "using: %s\n", ofdm->codename);
-            fprintf(stderr, "LDPC codeword data bits = %d\n", ldpc.ldpc_data_bits_per_frame);
-            fprintf(stderr, "LDPC codeword total bits  = %d\n", ldpc.ldpc_coded_bits_per_frame);
-            fprintf(stderr, "LDPC codeword data bits used = %d\n", Ndatabitsperpacket);
-            fprintf(stderr, "LDPC codeword total length in modem packet = %d\n", Npayloadbitsperpacket);
-        }
+  }
+
+  /* init the modem with our (optionally) custom config */
+  struct OFDM *ofdm = ofdm_create(ofdm_config);
+  assert(ofdm != NULL);
+
+  free(ofdm_config);
+
+  /* Get a copy of the completed modem config (ofdm_create() fills in more
+   * parameters) */
+  ofdm_config = ofdm_get_config_param(ofdm);
+
+  /* set up some useful constants */
+
+  int Nbitsperpacket = ofdm_get_bits_per_packet(ofdm);
+  int Npayloadbitsperpacket = Nbitsperpacket - ofdm->nuwbits - ofdm->ntxtbits;
+  int Nsamperpacket = ofdm_get_samples_per_packet(ofdm);
+
+  /* Set up LPDC code */
+
+  struct LDPC ldpc;
+  if (ldpc_en) {
+    ldpc_codes_setup(&ldpc, ofdm->codename);
+    ldpc_mode_specific_setup(ofdm, &ldpc);
+    Ndatabitsperpacket = ldpc.data_bits_per_frame;
+
+    if (verbose > 1) {
+      fprintf(stderr, "using: %s\n", ofdm->codename);
+      fprintf(stderr, "LDPC codeword data bits = %d\n",
+              ldpc.ldpc_data_bits_per_frame);
+      fprintf(stderr, "LDPC codeword total bits  = %d\n",
+              ldpc.ldpc_coded_bits_per_frame);
+      fprintf(stderr, "LDPC codeword data bits used = %d\n",
+              Ndatabitsperpacket);
+      fprintf(stderr, "LDPC codeword total length in modem packet = %d\n",
+              Npayloadbitsperpacket);
     }
-    else {
-        Ndatabitsperpacket = Npayloadbitsperpacket;
-    }
-
-    if (verbose) {
-        ofdm_set_verbose(ofdm, verbose);
-        fprintf(stderr, "Ndatabitsperpacket: %d Npayloadbitsperpacket: %d Nsamperpacket: %d\n",
-                Ndatabitsperpacket, Npayloadbitsperpacket, Nsamperpacket);
-    }
-
-    if (testframes) {
-        if (burst_mode)
-            Npackets = Nsec;                      // burst mode: treat Nsecs as Npackets/burst
-        else
-            Npackets = round(Nsec/ofdm->tpacket); // streaming mode
-        if (verbose)
-            fprintf(stderr, "Npackets: %d\n", Npackets);
+  } else {
+    Ndatabitsperpacket = Npayloadbitsperpacket;
+  }
+
+  if (verbose) {
+    ofdm_set_verbose(ofdm, verbose);
+    fprintf(
+        stderr,
+        "Ndatabitsperpacket: %d Npayloadbitsperpacket: %d Nsamperpacket: %d\n",
+        Ndatabitsperpacket, Npayloadbitsperpacket, Nsamperpacket);
+  }
+
+  if (testframes) {
+    if (burst_mode)
+      Npackets = Nsec;  // burst mode: treat Nsecs as Npackets/burst
+    else
+      Npackets = round(Nsec / ofdm->tpacket);  // streaming mode
+    if (verbose) fprintf(stderr, "Npackets: %d\n", Npackets);
+  }
+
+  if (clip_en) {
+    ofdm->clip_en = true;
+  }
+  if (txbpf_en) {
+    ofdm_set_tx_bpf(ofdm, 1);
+  }
+
+  uint8_t txt_bits[ofdm->ntxtbits];
+  memset(txt_bits, 0, ofdm->ntxtbits);
+  char text_str[] =
+      "cq cq cq hello world\r";  // Add text bits to match other tests
+  char *ptr_text = text_str;
+
+  short tx_varicode_bits[VARICODE_MAX_BITS];
+  int nvaricode_bits = 0;
+  int varicode_bit_index = 0;
+
+  complex float tx_sams[Nsamperpacket];
+  short tx_real[Nsamperpacket];
+
+  if (verbose > 1) ofdm_print_info(ofdm);
+
+  for (int b = 0; b < Nbursts; b++) {
+    if (burst_mode) {
+      fprintf(stderr, "Tx preamble\n");
+      complex float tx_preamble[ofdm->samplesperframe];
+      memcpy(tx_preamble, ofdm->tx_preamble,
+             sizeof(COMP) * ofdm->samplesperframe);
+      ofdm_hilbert_clipper(ofdm, tx_preamble, ofdm->samplesperframe);
+      for (i = 0; i < ofdm->samplesperframe; i++)
+        tx_real[i] = crealf(tx_preamble[i]);
+      fwrite(tx_real, sizeof(short), ofdm->samplesperframe, fout);
     }
 
-    if (clip_en) { ofdm->clip_en = true; }
-    if (txbpf_en) { ofdm_set_tx_bpf(ofdm, 1); }
+    /* main loop
+     * ----------------------------------------------------------------*/
+
+    int packet = 0;
+    uint8_t data_bits[Ndatabitsperpacket];
+    while (fread(data_bits, sizeof(uint8_t), Ndatabitsperpacket, fin) ==
+           Ndatabitsperpacket) {
+      if (ldpc_en) {
+        /* fancy LDPC encoded frames ----------------------------*/
+
+        /* optionally overwrite input data with test frame of
+           payload data bits known to demodulator */
+
+        if (testframes) {
+          if (use_text) {
+            // Get text bits
+            int nspare = ofdm->ntxtbits;
+            int k;
+
+            for (k = 0; k < nspare; k++) {
+              if (nvaricode_bits) {
+                txt_bits[k] = tx_varicode_bits[varicode_bit_index++];
+                nvaricode_bits--;
+              }
+
+              if (nvaricode_bits == 0) {
+                /* get new char and encode */
+                char s[2];
+                s[0] = *ptr_text++;
+
+                if (*ptr_text == 0) ptr_text = &text_str[0];
+
+                nvaricode_bits = varicode_encode(tx_varicode_bits, s,
+                                                 VARICODE_MAX_BITS, 1, 1);
+                varicode_bit_index = 0;
+              }
+            }
+          }
 
-    uint8_t txt_bits[ofdm->ntxtbits];
-    memset(txt_bits, 0, ofdm->ntxtbits);
-    char text_str[] = "cq cq cq hello world\r"; // Add text bits to match other tests
-    char *ptr_text = text_str;
+          ofdm_generate_payload_data_bits(data_bits, Ndatabitsperpacket);
+        }
 
-    short tx_varicode_bits[VARICODE_MAX_BITS];
-    int nvaricode_bits = 0;
-    int varicode_bit_index = 0;
+        ofdm_ldpc_interleave_tx(ofdm, &ldpc, tx_sams, data_bits, txt_bits);
+        for (i = 0; i < Nsamperpacket; i++) tx_real[i] = crealf(tx_sams[i]);
+      } else {
+        /* just modulate uncoded raw bits ------------------------------------*/
 
-    complex float tx_sams[Nsamperpacket];
-    short   tx_real[Nsamperpacket];
+        /* in uncoded mode entire payload is input data bits */
+        assert(Ndatabitsperpacket == Npayloadbitsperpacket);
 
-    if (verbose > 1) ofdm_print_info(ofdm);
+        if (testframes) {
+          /* build up a test frame consisting of unique word, txt bits, and
+             psuedo-random uncoded payload bits.  The psuedo-random generator is
+             the same as Octave so it can interoperate with ofdm_tx.m/ofdm_rx.m
+           */
 
-    for (int b=0; b<Nbursts; b++) {
-        if (burst_mode) {
-            fprintf(stderr, "Tx preamble\n");
-            complex float tx_preamble[ofdm->samplesperframe];
-            memcpy(tx_preamble, ofdm->tx_preamble, sizeof(COMP)*ofdm->samplesperframe);
-            ofdm_hilbert_clipper(ofdm, tx_preamble, ofdm->samplesperframe);
-            for (i = 0; i < ofdm->samplesperframe; i++) tx_real[i] = crealf(tx_preamble[i]);
-            fwrite(tx_real, sizeof (short), ofdm->samplesperframe, fout);
+          ofdm_generate_payload_data_bits(data_bits, Npayloadbitsperpacket);
         }
-    
-        /* main loop ----------------------------------------------------------------*/
-
-        int packet = 0;
-        uint8_t data_bits[Ndatabitsperpacket];
-        while (fread(data_bits, sizeof (uint8_t), Ndatabitsperpacket, fin) == Ndatabitsperpacket) {
-
-            if (ldpc_en) {
-                /* fancy LDPC encoded frames ----------------------------*/
-
-                /* optionally overwrite input data with test frame of
-                   payload data bits known to demodulator */
-
-                if (testframes) {
-
-                    if (use_text) {
-                        // Get text bits
-                        int nspare = ofdm->ntxtbits;
-                        int k;
-
-                        for (k = 0; k < nspare; k++) {
-                            if (nvaricode_bits) {
-                                txt_bits[k] = tx_varicode_bits[varicode_bit_index++];
-                                nvaricode_bits--;
-                            }
-
-                            if (nvaricode_bits == 0) {
-                                /* get new char and encode */
-                                char s[2];
-                                s[0] = *ptr_text++;
-
-                                if (*ptr_text == 0)
-                                    ptr_text = &text_str[0];
-
-                                nvaricode_bits = varicode_encode(tx_varicode_bits, s, VARICODE_MAX_BITS, 1, 1);
-                                varicode_bit_index = 0;
-                            }
-                        }
-                    }
-
-                    ofdm_generate_payload_data_bits(data_bits, Ndatabitsperpacket);
-                }
-
-                ofdm_ldpc_interleave_tx(ofdm, &ldpc, tx_sams, data_bits, txt_bits);
-                for (i = 0; i < Nsamperpacket; i++) tx_real[i] = crealf(tx_sams[i]);
-            } else {
-                /* just modulate uncoded raw bits ------------------------------------*/
-
-                /* in uncoded mode entire payload is input data bits */
-                assert(Ndatabitsperpacket == Npayloadbitsperpacket);
-
-                if (testframes) {
-                    /* build up a test frame consisting of unique word, txt bits, and psuedo-random
-                       uncoded payload bits.  The psuedo-random generator is the same as Octave so
-                       it can interoperate with ofdm_tx.m/ofdm_rx.m */
-
-                    ofdm_generate_payload_data_bits(data_bits, Npayloadbitsperpacket);
-                }
-
-                /* assemble packet of bits then modulate */
-                uint8_t tx_bits_char[Nbitsperpacket];
-                ofdm_assemble_qpsk_modem_packet(ofdm, tx_bits_char, data_bits, txt_bits);
-                int tx_bits[Nbitsperpacket];
-                for (i = 0; i < Nbitsperpacket; i++) tx_bits[i] = tx_bits_char[i];
-                COMP tx_sams[Nsamperpacket];
-                ofdm_mod(ofdm, tx_sams, tx_bits);
-                for (i = 0; i < Nsamperpacket; i++) tx_real[i] = tx_sams[i].real;
-            }
-
-            fwrite(tx_real, sizeof (short), Nsamperpacket, fout);
-            packet++;
 
-            if (testframes && (packet >= Npackets))
-                break;
-        }
+        /* assemble packet of bits then modulate */
+        uint8_t tx_bits_char[Nbitsperpacket];
+        ofdm_assemble_qpsk_modem_packet(ofdm, tx_bits_char, data_bits,
+                                        txt_bits);
+        int tx_bits[Nbitsperpacket];
+        for (i = 0; i < Nbitsperpacket; i++) tx_bits[i] = tx_bits_char[i];
+        COMP tx_sams[Nsamperpacket];
+        ofdm_mod(ofdm, tx_sams, tx_bits);
+        for (i = 0; i < Nsamperpacket; i++) tx_real[i] = tx_sams[i].real;
+      }
+
+      fwrite(tx_real, sizeof(short), Nsamperpacket, fout);
+      packet++;
+
+      if (testframes && (packet >= Npackets)) break;
+    }
 
-        if (burst_mode) {
-            // Post-amble 
-            fprintf(stderr, "Tx postamble\n");
-            complex float tx_postamble[ofdm->samplesperframe];
-            memcpy(tx_postamble, ofdm->tx_postamble, sizeof(COMP)*ofdm->samplesperframe);
-            ofdm_hilbert_clipper(ofdm, tx_postamble, ofdm->samplesperframe);
-            for (i = 0; i < ofdm->samplesperframe; i++) tx_real[i] = crealf(tx_postamble[i]);
-            fwrite(tx_real, sizeof (short), ofdm->samplesperframe, fout);
-            // Interburst silence
-            int samples_delay = ofdm->fs;
-            short sil_short[samples_delay];
-            for(int i=0; i<samples_delay; i++) sil_short[i] = 0;
-            fwrite(sil_short, sizeof(short), samples_delay, fout);
-        }
+    if (burst_mode) {
+      // Post-amble
+      fprintf(stderr, "Tx postamble\n");
+      complex float tx_postamble[ofdm->samplesperframe];
+      memcpy(tx_postamble, ofdm->tx_postamble,
+             sizeof(COMP) * ofdm->samplesperframe);
+      ofdm_hilbert_clipper(ofdm, tx_postamble, ofdm->samplesperframe);
+      for (i = 0; i < ofdm->samplesperframe; i++)
+        tx_real[i] = crealf(tx_postamble[i]);
+      fwrite(tx_real, sizeof(short), ofdm->samplesperframe, fout);
+      // Interburst silence
+      int samples_delay = ofdm->fs;
+      short sil_short[samples_delay];
+      for (int i = 0; i < samples_delay; i++) sil_short[i] = 0;
+      fwrite(sil_short, sizeof(short), samples_delay, fout);
     }
+  }
 
-    if (input_specified)
-        fclose(fin);
+  if (input_specified) fclose(fin);
 
-    if (output_specified)
-        fclose(fout);
+  if (output_specified) fclose(fout);
 
-    ofdm_destroy(ofdm);
+  ofdm_destroy(ofdm);
 
-    return 0;
+  return 0;
 }