{
  "ok": true,
  "mode": "JS8",
  "tool": "webftr-js8-real-ldpc-matrix-syndrome-probe",
  "tool_version": "step37-timing-best-candidate-softdecode",
  "input_wav": null,
  "candidate_json": "/decoders/js8_decoder/runtime/timing_boundary_sweep/step37_best_timing_fec_candidate.json",
  "rx_only": true,
  "safety": {
    "tx": false,
    "ptt": false,
    "tune": false,
    "send": false,
    "js8call_runtime_control": false
  },
  "implementation_stage": "step37_bounded_gray_interleaver_matrix_ranking_no_message_unpack",
  "matrix": {
    "code": "(174,91) LDPC generator matrix",
    "generator_rows": 83,
    "generator_cols": 91,
    "message_bits": 91,
    "parity_bits": 83,
    "source_file": "ldpc_174_91_c_generator.f90"
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    "total_transform_rows_before_limit": 828,
    "max_rows": 72,
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    "nsps_is_js8_realistic": true,
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      "transform": "raw_msb+no_interleaver",
      "mapping_meta": {
        "tone_mapping": "raw_msb",
        "interleaver": "none"
      },
      "hard_weight_174": 32,
      "llr_avg_abs": 1.7837172241379298,
      "syndrome": {
        "bits_len": 174,
        "message91": "0111000010001000000010000000010000110000000101000000000011100000100100000000010010000000000",
        "parity83_observed": "00000100001100000001010100000000110000000000001110000000001001000000000000000000100",
        "parity83_expected": "00011001011001100110110110000000011100000000101010100010110011011110000101000110100",
        "syndrome83": "00011101010101100111100010000000101100000000100100100010111010011110000101000110000",
        "syndrome_weight": 32,
        "valid_codeword_hard_decision": false,
        "message91_sha256_16": "1ef6c5c26dfbc68b",
        "codeword174_sha256_16": "d96e8c7a3ce0490d"
      },
      "repair": {
        "attempted": false,
        "flip_count": 0,
        "repair_success": false,
        "final_syndrome_weight": 32,
        "trace": [],
        "repaired_message91_sha256_16": "1ef6c5c26dfbc68b"
      }
    },
    {
      "variant": "mapped_ft8_gray_alt_high_demap_msb_input+no_interleaver",
      "transform": "raw_msb+ft8_bitrev_interleave_codeword_to_rx_inverse",
      "mapping_meta": {
        "tone_mapping": "raw_msb",
        "interleaver": "ft8_bitrev",
        "direction": "interleave_codeword_to_rx_inverse",
        "order_len": 174
      },
      "hard_weight_174": 32,
      "llr_avg_abs": 1.7837172241379298,
      "syndrome": {
        "bits_len": 174,
        "message91": "0111000010001000000010000000010000110000000101000000000011100000100100000000010010000000000",
        "parity83_observed": "00000100001100000001010100000000110000000000001110000000001001000000000000000000100",
        "parity83_expected": "00011001011001100110110110000000011100000000101010100010110011011110000101000110100",
        "syndrome83": "00011101010101100111100010000000101100000000100100100010111010011110000101000110000",
        "syndrome_weight": 32,
        "valid_codeword_hard_decision": false,
        "message91_sha256_16": "1ef6c5c26dfbc68b",
        "codeword174_sha256_16": "d96e8c7a3ce0490d"
      },
      "repair": {
        "attempted": false,
        "flip_count": 0,
        "repair_success": false,
        "final_syndrome_weight": 32,
        "trace": [],
        "repaired_message91_sha256_16": "1ef6c5c26dfbc68b"
      }
    },
    {
      "variant": "mapped_lsb_within_each_tone+no_interleaver",
      "transform": "ft8_gray_alt_high_demap_lsb_input+ft8_bitrev_interleave_codeword_to_rx_inverse",
      "mapping_meta": {
        "tone_mapping": "ft8_gray_alt_high",
        "gray_direction": "inverse_observed_to_plain",
        "reverse_bits_within_tone_before_gray": true,
        "interleaver": "ft8_bitrev",
        "direction": "interleave_codeword_to_rx_inverse",
        "order_len": 174
      },
      "hard_weight_174": 32,
      "llr_avg_abs": 1.7837172241379298,
      "syndrome": {
        "bits_len": 174,
        "message91": "0111000010001000000010000000010000110000000101000000000011100000100100000000010010000000000",
        "parity83_observed": "00000100001100000001010100000000110000000000001110000000001001000000000000000000100",
        "parity83_expected": "00011001011001100110110110000000011100000000101010100010110011011110000101000110100",
        "syndrome83": "00011101010101100111100010000000101100000000100100100010111010011110000101000110000",
        "syndrome_weight": 32,
        "valid_codeword_hard_decision": false,
        "message91_sha256_16": "1ef6c5c26dfbc68b",
        "codeword174_sha256_16": "d96e8c7a3ce0490d"
      },
      "repair": {
        "attempted": false,
        "flip_count": 0,
        "repair_success": false,
        "final_syndrome_weight": 32,
        "trace": [],
        "repaired_message91_sha256_16": "1ef6c5c26dfbc68b"
      }
    },
    {
      "variant": "mapped_raw_msb+no_interleaver",
      "transform": "ft8_gray_alt_high_demap_msb_input+ft8_bitrev_interleave_codeword_to_rx_inverse",
      "mapping_meta": {
        "tone_mapping": "ft8_gray_alt_high",
        "gray_direction": "inverse_observed_to_plain",
        "reverse_bits_within_tone_before_gray": false,
        "interleaver": "ft8_bitrev",
        "direction": "interleave_codeword_to_rx_inverse",
        "order_len": 174
      },
      "hard_weight_174": 32,
      "llr_avg_abs": 1.7837172241379298,
      "syndrome": {
        "bits_len": 174,
        "message91": "0111000010001000000010000000010000110000000101000000000011100000100100000000010010000000000",
        "parity83_observed": "00000100001100000001010100000000110000000000001110000000001001000000000000000000100",
        "parity83_expected": "00011001011001100110110110000000011100000000101010100010110011011110000101000110100",
        "syndrome83": "00011101010101100111100010000000101100000000100100100010111010011110000101000110000",
        "syndrome_weight": 32,
        "valid_codeword_hard_decision": false,
        "message91_sha256_16": "1ef6c5c26dfbc68b",
        "codeword174_sha256_16": "d96e8c7a3ce0490d"
      },
      "repair": {
        "attempted": false,
        "flip_count": 0,
        "repair_success": false,
        "final_syndrome_weight": 32,
        "trace": [],
        "repaired_message91_sha256_16": "1ef6c5c26dfbc68b"
      }
    },
    {
      "variant": "raw_msb_symbol_order",
      "transform": "ft8_gray_alt_high_demap_msb_input+ft8_bitrev_interleave_codeword_to_rx_inverse",
      "mapping_meta": {
        "tone_mapping": "ft8_gray_alt_high",
        "gray_direction": "inverse_observed_to_plain",
        "reverse_bits_within_tone_before_gray": false,
        "interleaver": "ft8_bitrev",
        "direction": "interleave_codeword_to_rx_inverse",
        "order_len": 174
      },
      "hard_weight_174": 32,
      "llr_avg_abs": 1.7837172241379298,
      "syndrome": {
        "bits_len": 174,
        "message91": "0111000010001000000010000000010000110000000101000000000011100000100100000000010010000000000",
        "parity83_observed": "00000100001100000001010100000000110000000000001110000000001001000000000000000000100",
        "parity83_expected": "00011001011001100110110110000000011100000000101010100010110011011110000101000110100",
        "syndrome83": "00011101010101100111100010000000101100000000100100100010111010011110000101000110000",
        "syndrome_weight": 32,
        "valid_codeword_hard_decision": false,
        "message91_sha256_16": "1ef6c5c26dfbc68b",
        "codeword174_sha256_16": "d96e8c7a3ce0490d"
      },
      "repair": {
        "attempted": false,
        "flip_count": 0,
        "repair_success": false,
        "final_syndrome_weight": 32,
        "trace": [],
        "repaired_message91_sha256_16": "1ef6c5c26dfbc68b"
      }
    },
    {
      "variant": "mapped_ft8_gray_alt_high_demap_msb_input+no_interleaver",
      "transform": "ft8_gray_primary_demap_msb_input+ft8_bitrev_interleave_codeword_to_rx_inverse+inverted_bits",
      "mapping_meta": {
        "tone_mapping": "ft8_gray_primary",
        "gray_direction": "inverse_observed_to_plain",
        "reverse_bits_within_tone_before_gray": false,
        "interleaver": "ft8_bitrev",
        "direction": "interleave_codeword_to_rx_inverse",
        "order_len": 174,
        "polarity": "inverted"
      },
      "hard_weight_174": 134,
      "llr_avg_abs": 1.5783320287356328,
      "syndrome": {
        "bits_len": 174,
        "message91": "1000111101110111111101111111011111101111111110111111101100001111011110111111101111111111101",
        "parity83_observed": "11111011010011111110101010111110001111101011110001111101110100111111111111110111011",
        "parity83_expected": "00111101001101011010011010110110001111011001101100111001110101111010000001111101010",
        "syndrome83": "11000110011110100100110000001000000000110010011101000100000001000101111110001010001",
        "syndrome_weight": 32,
        "valid_codeword_hard_decision": false,
        "message91_sha256_16": "7fcb9ce8ce209d99",
        "codeword174_sha256_16": "fffaa3a9661b23ea"
      },
      "repair": {
        "attempted": false,
        "flip_count": 0,
        "repair_success": false,
        "final_syndrome_weight": 32,
        "trace": [],
        "repaired_message91_sha256_16": "7fcb9ce8ce209d99"
      }
    },
    {
      "variant": "mapped_ft8_gray_alt_high_demap_msb_input+no_interleaver",
      "transform": "ft8_gray_primary_demap_msb_input+ft8_bitrev_deinterleave_rx_to_codeword",
      "mapping_meta": {
        "tone_mapping": "ft8_gray_primary",
        "gray_direction": "inverse_observed_to_plain",
        "reverse_bits_within_tone_before_gray": false,
        "interleaver": "ft8_bitrev",
        "direction": "deinterleave_rx_to_codeword",
        "order_len": 174
      },
      "hard_weight_174": 40,
      "llr_avg_abs": 1.5783320287356315,
      "syndrome": {
        "bits_len": 174,
        "message91": "0001000000000010001100000000000100100000111001100000000010101000000100010000000001000010100",
        "parity83_observed": "01100001100000001110000001010001011010010000000100000000100000001001100000000001010",
        "parity83_expected": "11011011100000001111010110100011011010001100000100000111000000110100010001101001100",
        "syndrome83": "10111010000000000001010111110010000000011100000000000111100000111101110001101000110",
        "syndrome_weight": 32,
        "valid_codeword_hard_decision": false,
        "message91_sha256_16": "eeb4d939762c19d7",
        "codeword174_sha256_16": "a064e1b9f911fff9"
      },
      "repair": {
        "attempted": false,
        "flip_count": 0,
        "repair_success": false,
        "final_syndrome_weight": 32,
        "trace": [],
        "repaired_message91_sha256_16": "eeb4d939762c19d7"
      }
    },
    {
      "variant": "lsb_within_each_tone",
      "transform": "ft8_gray_alt_high_demap_lsb_input+ft8_bitrev_interleave_codeword_to_rx_inverse",
      "mapping_meta": {
        "tone_mapping": "ft8_gray_alt_high",
        "gray_direction": "inverse_observed_to_plain",
        "reverse_bits_within_tone_before_gray": true,
        "interleaver": "ft8_bitrev",
        "direction": "interleave_codeword_to_rx_inverse",
        "order_len": 174
      },
      "hard_weight_174": 32,
      "llr_avg_abs": 1.5689645287356313,
      "syndrome": {
        "bits_len": 174,
        "message91": "0111000010001000000010000000010000110000000101000000000011100000100100000000010010000000000",
        "parity83_observed": "00000100001100000001010100000000110000000000001110000000001001000000000000000000100",
        "parity83_expected": "00011001011001100110110110000000011100000000101010100010110011011110000101000110100",
        "syndrome83": "00011101010101100111100010000000101100000000100100100010111010011110000101000110000",
        "syndrome_weight": 32,
        "valid_codeword_hard_decision": false,
        "message91_sha256_16": "1ef6c5c26dfbc68b",
        "codeword174_sha256_16": "d96e8c7a3ce0490d"
      },
      "repair": {
        "attempted": false,
        "flip_count": 0,
        "repair_success": false,
        "final_syndrome_weight": 32,
        "trace": [],
        "repaired_message91_sha256_16": "1ef6c5c26dfbc68b"
      }
    },
    {
      "variant": "mapped_raw_msb+ft8_bitrev_interleave_codeword_to_rx_inverse",
      "transform": "ft8_gray_alt_high_demap_lsb_input+no_interleaver+inverted_bits",
      "mapping_meta": {
        "tone_mapping": "ft8_gray_alt_high",
        "gray_direction": "inverse_observed_to_plain",
        "reverse_bits_within_tone_before_gray": true,
        "interleaver": "none",
        "polarity": "inverted"
      },
      "hard_weight_174": 122,
      "llr_avg_abs": 1.5576050229885054,
      "syndrome": {
        "bits_len": 174,
        "message91": "0101100011111101110011111111001110011101111111101110010010111111001111101110011111111110011",
        "parity83_observed": "11111110000110111001100110111001101111111110001101001100001010111111111111111111110",
        "parity83_expected": "11111101000110001011000010011101101111100100010011000000110110010101110111100001011",
        "syndrome83": "00000011000000110010100100100100000000011010011110001100111100101010001000011110101",
        "syndrome_weight": 32,
        "valid_codeword_hard_decision": false,
        "message91_sha256_16": "6b1e08b5e23278be",
        "codeword174_sha256_16": "2ebc0e51aa0056a9"
      },
      "repair": {
        "attempted": false,
        "flip_count": 0,
        "repair_success": false,
        "final_syndrome_weight": 32,
        "trace": [],
        "repaired_message91_sha256_16": "6b1e08b5e23278be"
      }
    }
  ],
  "decodes": [],
  "outputs": {
    "ldpc_matrix_probe_json": "/decoders/js8_decoder/runtime/ldpc_matrix_probe/step37_ldpc_matrix_probe.json"
  },
  "warnings": [
    "Step 37 keeps the Step 37 Gray/interleaver probe but ranks all mappings first and repairs only the best bounded subset to avoid Raspberry Pi timeouts.",
    "This is still a diagnostic LDPC/FEC probe and does not unpack JS8 text yet.",
    "If best_matrix_probe reaches syndrome_weight 0, the next step can feed message91 into CRC/message unpack. Otherwise continue timing, symbol boundary, deinterleaver/order or LLR tuning using best mapping_meta."
  ],
  "next_action": "Upload Step35 logs. Inspect best_matrix_probe.mapping_meta and final_syndrome_weight; then either unpack message91 on syndrome 0 or continue bounded LDPC/timing tuning."
}