From 4b12986dc0487c7d6f96c917e1d18819ad2037e7 Mon Sep 17 00:00:00 2001
From: Ahmet Inan <xdsopl@gmail.com>
Date: Sun, 13 Jul 2025 08:40:51 +0200
Subject: [PATCH] now we can try more combinations on first symbol

---
 decode.cc | 10 +++++-----
 encode.cc |  4 ++--
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/decode.cc b/decode.cc
index b2de035..9b2168d 100644
--- a/decode.cc
+++ b/decode.cc
@@ -232,12 +232,12 @@ struct Decoder : Common
 				meta[i] = clamp(std::nearbyint(127 * demod_or_erase(fdom[bin(i*block_length+first_meta+tone_off)], chan[i*block_length+first_meta]).real() * nrz(seq1())));
 				seq1();
 			}
-			int mode = hadamard_decoder(meta);
-			if (mode < 0 || mode > 7) {
-				std::cerr << "operation mode " << mode << " unsupported." << std::endl;
+			int meta_data = hadamard_decoder(meta);
+			if (meta_data < 0) {
+				std::cerr << "meta data damaged" << std::endl;
 				continue;
 			}
-			setup(mode);
+			setup(meta_data >> 3);
 			std::cerr << "oper mode: " << oper_mode << std::endl;
 			if (oper_mode >= 3) {
 				for (int i = 0; i < tone_count; ++i)
@@ -319,7 +319,7 @@ struct Decoder : Common
 						chan[i] = DSP::lerp(chan[i], tone[i], value(0.5));
 				}
 				CODE::XorShiftMask<int, 14, 1, 5, 10, 1> combination;
-				int trial = j ? (meta_data << 6) | seed_data : seed_data;
+				int trial = j ? (meta_data << 6) | seed_data : (meta_data & 7) << 6 | seed_data;
 				int comb = 0;
 				for (int i = 0; i <= trial; ++i)
 					comb = combination();
diff --git a/encode.cc b/encode.cc
index e99bd7b..aa4da26 100644
--- a/encode.cc
+++ b/encode.cc
@@ -80,14 +80,14 @@ struct Encoder : public Common
 		for (int i = 0; differential && symbol_number > 0 && i < tone_count; ++i)
 			tone[i] *= prev[i];
 		value best_papr = 1000;
-		int trials = symbol_number ? 4096 : 64;
+		int trials = symbol_number ? 4096 : 512;
 		CODE::XorShiftMask<int, 14, 1, 5, 10, 1> combination;
 		for (int trial = 0; trial < trials; ++trial) {
 			for (int i = 0; i < tone_count; ++i)
 				temp[i] = tone[i];
 			if (symbol_number >= 0) {
 				int comb = combination();
-				int meta_data = symbol_number ? trial >> 6 : oper_mode;
+				int meta_data = symbol_number ? trial >> 6 : (oper_mode << 3) | (trial >> 6);
 				hadamard_encoder(meta, meta_data);
 				int seed_data = trial & 63;
 				hadamard_encoder(seed, seed_data);