Make number of short payload bits a command line parameter.

 * use --short <bits> where bits is one of 12, 16 or 20.
Signed-off-by: Stefan Westerfeld <stefan@space.twc.de>

src/audiowmark.cc

@@ -26,6 +26,7 @@
 #include "utils.hh"
 #include "random.hh"
 #include "wmcommon.hh"
+#include "shortcode.hh"
 
 #include <assert.h>
 
@@ -57,7 +58,7 @@ print_usage()
   printf ("Global options:\n");
   printf ("  --strength <s>        set watermark strength              [%.6g]\n", Params::water_delta * 1000);
   printf ("  --linear              disable non-linear bit storage\n");
-  printf ("  --short               enable short payload mode (12 bits)\n");
+  printf ("  --short <bits>        enable short payload mode\n");
   printf ("  --key <file>          load watermarking key from file\n");
   printf ("  -q, --quiet           disable information messages\n");
   printf ("\n");
@@ -184,9 +185,14 @@ parse_options (int   *argc_p,
 	{
           Params::mix = false;
 	}
-      else if (check_arg (argc, argv, &i, "--short"))
+      else if (check_arg (argc, argv, &i, "--short", &opt_arg))
         {
-          Params::payload_size = 12;
+          Params::payload_size = atoi (opt_arg);
+          if (!short_code_init (Params::payload_size))
+            {
+              error ("audiowmark: unsupported short payload size %zd\n", Params::payload_size);
+              exit (1);
+            }
           Params::payload_short = true;
         }
       else if (check_arg (argc, argv, &i, "--hard"))

src/shortcode.cc

@@ -25,7 +25,6 @@ using std::vector;
 
 /* Codes from codetables.de / magma online calculator BKLC (GF(2), N, K) */
 
-#if 0
 static vector<vector<int>> block_65_20_20 = {
   {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,1,0,1,1,1,1,1,1,1,0,1,0,0,0,0,0,0,1,1,1,1,1,1,1,1,0,1,0,1,1,1,1,1,0,0,1,1,1,0,1,1,1},
   {0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1,0,1,0,1,0,0,0,1,1,0,1,0,0,0,0,0,1,1,1,1,0,1,1,0,0,1,0,0,0,0,0,1,1,1,0,1,1,1,1,1,1},
@@ -49,12 +48,6 @@ static vector<vector<int>> block_65_20_20 = {
   {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,1,0,1,1,1,0,1,1,1,0,0,0,0,0,0,0,0,0,1,0,0,1,0,0,0,1,1,1,1,0,1,1,1,0,0,1,0,0,0,0,1},
 };
 
-static const auto&   gen_matrix    = block_65_20_20;
-static constexpr int gen_in_count  = 20;
-static constexpr int gen_out_count = 65;
-#endif
-
-#if 0
 static vector<vector<int>> block_61_16_21 = {
   {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,1,0,1,1,1,0,1,0,1,1,1,1,1,1,0,0,1,0,0,0,0,1,0,1,0,0,0,0,0,1,1,0,0,1,0,0,1,0,0},
   {0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1,0,0,1,0,1,1,1,0,1,0,1,1,1,1,1,1,0,0,1,0,0,0,0,1,0,1,0,0,0,0,0,1,1,0,0,1,0,0,1,0},
@@ -74,11 +67,6 @@ static vector<vector<int>> block_61_16_21 = {
   {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,1,1,0,0,0,1,0,0,0,1,1,1,1,1,1,1,1,0,1,0,1,1,0,1,0,1,0,1,1,0,1,1,1,1,0,1,0,1,1,1,0,1,1},
 };
 
-static const auto&   gen_matrix    = block_61_16_21;
-static constexpr int gen_in_count  = 16;
-static constexpr int gen_out_count = 61;
-#endif
-
 static vector<vector<int>> block_56_12_22 = {
   { 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1 },
   { 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0 },
@@ -94,9 +82,37 @@ static vector<vector<int>> block_56_12_22 = {
   { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1 },
 };
 
-static const auto&   gen_matrix    = block_56_12_22;
-static constexpr int gen_in_count  = 12;
-static constexpr int gen_out_count = 56;
+static vector<vector<int>> gen_matrix;
+static size_t              gen_in_count = 0;
+static size_t              gen_out_count = 0;
+
+size_t
+short_code_init (size_t k)
+{
+  if (k == 12)
+    {
+      gen_matrix    = block_56_12_22;
+      gen_in_count  = 12;
+      gen_out_count = 56;
+    }
+  else if (k == 16)
+    {
+      gen_matrix    = block_61_16_21;
+      gen_in_count  = 16;
+      gen_out_count = 61;
+    }
+  else if (k == 20)
+    {
+      gen_matrix    = block_65_20_20;
+      gen_in_count  = 20;
+      gen_out_count = 65;
+    }
+  else /* unsupported k */
+    {
+      return 0;
+    }
+  return gen_out_count;
+}
 
 vector<int>
 code_encode (ConvBlockType block_type, const vector<int>& in_bits)
@@ -157,7 +173,7 @@ vector<int>
 short_decode_blk (const vector<int>& coded_bits)
 {
   vector<int> out_bits;
-  for (size_t c = 0; c < (1 << gen_in_count); c++)
+  for (size_t c = 0; c < size_t (1 << gen_in_count); c++)
     {
       bool match = true;
       for (size_t j = 0; j < gen_out_count; j++)
@@ -201,10 +217,3 @@ short_decode_soft (ConvBlockType block_type, const std::vector<float>& coded_bit
 {
   return short_decode_blk (conv_decode_soft (block_type, coded_bits, error_out));
 }
-
-void
-short_code_get_n_k (size_t& n, size_t& k)
-{
-  k = gen_in_count;
-  n = gen_out_count;
-}

src/shortcode.hh

@@ -33,6 +33,6 @@ std::vector<int> short_decode_soft (ConvBlockType block_type, const std::vector<
 
 std::vector<int> short_encode_blk (const std::vector<int>& in_bits);
 std::vector<int> short_decode_blk (const std::vector<int>& coded_bits);
-void             short_code_get_n_k (size_t& n, size_t& k);
+size_t           short_code_init (size_t k);
 
 #endif /* AUDIOWMARK_SHORT_CODE_HH */

src/testshortcode.cc

@@ -84,13 +84,23 @@ number_format (double d)
 int
 main (int argc, char **argv)
 {
-  size_t N, K;
-  short_code_get_n_k (N, K);
-  printf ("using (%zd,%zd) code\n", N, K);
-
   srand (time (NULL));
 
-  if (argc == 1)
+  if (argc < 2)
+    {
+      printf ("first argument must be code size (12, 16, 20)\n");
+      return 1;
+    }
+  size_t K = atoi (argv[1]);
+  size_t N = short_code_init (K);
+  if (!N)
+    {
+      printf ("bad code size\n");
+      return 1;
+    }
+  printf ("using (%zd,%zd) code\n", N, K);
+
+  if (argc == 2)
     {
       vector<int> in_bits;
       while (in_bits.size() != K)
@@ -113,7 +123,7 @@ main (int argc, char **argv)
         printf ("%d", b);
       printf ("\n");
     }
-  if (argc == 2 && string (argv[1]) == "perf")
+  if (argc == 3 && string (argv[2]) == "perf")
     {
       const double start_t = gettime();
       const size_t runs = 100;
@@ -128,7 +138,7 @@ main (int argc, char **argv)
         }
       printf ("%.1f ms/block\n", (gettime() - start_t) / runs * 1000.0);
     }
-  if (argc == 2 && string (argv[1]) == "table")
+  if (argc == 3 && string (argv[2]) == "table")
     {
       map<vector<int>, vector<int>> table;
       vector<int> weight (N + 1);
@@ -179,7 +189,7 @@ main (int argc, char **argv)
             }
         }
     }
-  if (argc == 2 && string (argv[1]) == "distance")
+  if (argc == 3 && string (argv[2]) == "distance")
     {
       vector<vector<int>> cwords;
       for (size_t i = 0; i < size_t (1 << K); i++)