let's have at least one 1 second mode

README.md

@@ -3,10 +3,10 @@
 
 Quick start:
 
-Create file ```uncoded.dat``` with ```8192``` bits of random data:
+Create file ```uncoded.dat``` with ```2048``` bits of random data:
 
 ```
-dd if=/dev/urandom of=uncoded.dat bs=1 count=1024
+dd if=/dev/urandom of=uncoded.dat bs=1 count=256
 ```
 
 Encode file ```uncoded.dat``` to ```encoded.wav``` [WAV](https://en.wikipedia.org/wiki/WAV) audio file with 8000 Hz sample rate, 16 bits and only 1 (real) channel:
@@ -44,16 +44,16 @@ diff -s uncoded.dat decoded.dat
 All modes need a bandwidth of 2000 Hz and use a 1/2-rate forward error correction code
 
 These use a differential modulation scheme:
-* Mode 0: DBPSK, 3.06 seconds and 256 bytes
-* Mode 1: DQPSK, 3.06 seconds and 512 bytes
-* Mode 2: D8PSK, 4.08 seconds and 1024 bytes
+* Mode 0: DBPSK, 3 seconds and 256 bytes
+* Mode 1: DQPSK, 3 seconds and 512 bytes
+* Mode 2: D8PSK, 4 seconds and 1024 bytes
 
 And these a coherent modulation scheme:
-* Mode 3: BPSK, 3.06 seconds and 256 bytes
-* Mode 4: QPSK, 3.06 seconds and 512 bytes
-* Mode 5: QAM16, 3.06 seconds and 1024 bytes
-* Mode 6: QAM64, 4.08 seconds and 2048 bytes
-* Mode 7: QAM256, 5.78 seconds and 4096 bytes
+* Mode 3: BPSK, 3 seconds and 256 bytes
+* Mode 4: QPSK, 3 seconds and 512 bytes
+* Mode 5: QAM16, 1 second and 256 bytes
+* Mode 6: QAM16, 3 seconds and 1024 bytes
+* Mode 7: QAM64, 4 seconds and 2048 bytes
 
 ### Simulating
 

common.hh

@@ -13,10 +13,10 @@ Copyright 2025 Ahmet Inan <inan@aicodix.de>
 struct Common
 {
 	static const int mod_max = 8;
-	static const int code_max = 16;
+	static const int code_max = 15;
 	static const int bits_max = 1 << code_max;
-	static const int data_max = 4096;
-	static const int symbols_max = 32;
+	static const int data_max = 2048;
+	static const int symbols_max = 22;
 	static const int mls0_poly = 0x331;
 	static const int mls0_seed = 214;
 	static const int mls1_poly = 0x43;
@@ -95,6 +95,14 @@ struct Common
 			frozen_bits = frozen_8192_4128;
 			break;
 		case 5:
+			mod_bits = 4;
+			symbol_count = 4;
+			differential = false;
+			code_order = 12;
+			data_bits = 2048;
+			frozen_bits = frozen_4096_2080;
+			break;
+		case 6:
 			mod_bits = 4;
 			symbol_count = 16;
 			differential = false;
@@ -102,7 +110,7 @@ struct Common
 			data_bits = 8192;
 			frozen_bits = frozen_16384_8224;
 			break;
-		case 6:
+		case 7:
 			mod_bits = 6;
 			symbol_count = 22;
 			differential = false;
@@ -110,14 +118,6 @@ struct Common
 			data_bits = 16384;
 			frozen_bits = frozen_32768_16416;
 			break;
-		case 7:
-			mod_bits = 8;
-			symbol_count = 32;
-			differential = false;
-			code_order = 16;
-			data_bits = 32768;
-			frozen_bits = frozen_65536_32800;
-			break;
 		default:
 			return;
 		}

decode.cc

@@ -160,11 +160,6 @@ struct Decoder : Common
 			dest[0] = src[0];
 			for (int i = 1; i < 32768; ++i)
 				dest[seq()] = src[i];
-		} else if (code_order == 16) {
-			CODE::XorShiftMask<int, 16, 1, 1, 14, 1> seq;
-			dest[0] = src[0];
-			for (int i = 1; i < 65536; ++i)
-				dest[seq()] = src[i];
 		}
 	}
 	const cmplx *next_sample()
@@ -338,7 +333,7 @@ struct Decoder : Common
 						int bits = mod_bits;
 						if (oper_mode == 2 && l % 32 == 30)
 							bits = 2;
-						if (oper_mode == 6 && l % 64 == 60)
+						if (oper_mode == 7 && l % 64 == 60)
 							bits = 4;
 						demap_hard(perm+l, demod[i], bits);
 						hard = map_bits(perm+l, bits);
@@ -356,7 +351,7 @@ struct Decoder : Common
 						int bits = mod_bits;
 						if (oper_mode == 2 && k % 32 == 30)
 							bits = 2;
-						if (oper_mode == 6 && k % 64 == 60)
+						if (oper_mode == 7 && k % 64 == 60)
 							bits = 4;
 						demap_soft(perm+k, demod[i], precision, bits);
 						k += bits;

encode.cc

@@ -229,11 +229,6 @@ struct Encoder : public Common
 			dest[0] = src[0];
 			for (int i = 1; i < 32768; ++i)
 				dest[i] = src[seq()];
-		} else if (code_order == 16) {
-			CODE::XorShiftMask<int, 16, 1, 1, 14, 1> seq;
-			dest[0] = src[0];
-			for (int i = 1; i < 65536; ++i)
-				dest[i] = src[seq()];
 		}
 	}
 	void guard_interval_weights()
@@ -289,7 +284,7 @@ struct Encoder : public Common
 						int bits = mod_bits;
 						if (oper_mode == 2 && k % 32 == 30)
 							bits = 2;
-						if (oper_mode == 6 && k % 64 == 60)
+						if (oper_mode == 7 && k % 64 == 60)
 							bits = 4;
 						tone[i] = map_bits(perm+k, bits);
 						k += bits;

freezer.cc

@@ -27,7 +27,6 @@ void code(int N, int K, double P)
 
 int main()
 {
-	code<16>(65536, 32768+32, 0.42);
 	code<15>(32768, 16384+32, 0.40);
 	code<14>(16384, 8192+32, 0.39);
 	code<13>(8192, 4096+32, 0.38);