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start parity bits early, as we use a crc at the end

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This commit is contained in:
Ahmet Inan 2024-01-21 11:01:18 +01:00
commit 2d765a78fd
2 changed files with 38 additions and 2 deletions
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20
decode.cc
View file

@ -378,6 +378,8 @@ struct Decoder
if (!okay || !oper_mode)
return;
int parity_stride = 0;
int first_parity = 0;
int data_bits = 0;
int cons_rows = 0;
int comb_cols = 0;
@ -390,6 +392,8 @@ struct Decoder
code_order = 12;
code_cols = 256;
data_bits = 2048;
parity_stride = 31;
first_parity = 3;
frozen_bits = frozen_4096_2147;
break;
case 24:
@ -399,6 +403,8 @@ struct Decoder
code_order = 13;
code_cols = 256;
data_bits = 4096;
parity_stride = 31;
first_parity = 5;
frozen_bits = frozen_8192_4261;
break;
case 25:
@ -408,6 +414,8 @@ struct Decoder
code_order = 14;
code_cols = 256;
data_bits = 8192;
parity_stride = 31;
first_parity = 9;
frozen_bits = frozen_16384_8489;
break;
case 26:
@ -417,6 +425,8 @@ struct Decoder
code_order = 12;
code_cols = 256;
data_bits = 2048;
parity_stride = 31;
first_parity = 3;
frozen_bits = frozen_4096_2147;
break;
case 27:
@ -426,6 +436,8 @@ struct Decoder
code_order = 13;
code_cols = 256;
data_bits = 4096;
parity_stride = 31;
first_parity = 5;
frozen_bits = frozen_8192_4261;
break;
case 28:
@ -435,6 +447,8 @@ struct Decoder
code_order = 14;
code_cols = 256;
data_bits = 8192;
parity_stride = 31;
first_parity = 9;
frozen_bits = frozen_16384_8489;
break;
case 29:
@ -444,6 +458,8 @@ struct Decoder
code_order = 13;
code_cols = 273;
data_bits = 4096;
parity_stride = 31;
first_parity = 5;
frozen_bits = frozen_8192_4261;
break;
case 30:
@ -453,6 +469,8 @@ struct Decoder
code_order = 14;
code_cols = 273;
data_bits = 8192;
parity_stride = 31;
first_parity = 9;
frozen_bits = frozen_16384_8489;
break;
default:
@ -566,7 +584,7 @@ struct Decoder
for (int i = code_cols * cons_rows * mod_bits; i < bits_max; ++i)
code[i] = 0;
shuffle(code);
polardec(metric, mesg, code, frozen_bits, code_order, 31);
polardec(metric, mesg, code, frozen_bits, code_order, parity_stride, first_parity);
int order[mesg_type::SIZE];
for (int k = 0; k < mesg_type::SIZE; ++k)
order[k] = k;

20
encode.cc
View file

@ -249,6 +249,8 @@ struct Encoder
oper_mode(oper_mode)
{
const uint32_t *frozen_bits = nullptr;
int parity_stride = 0;
int first_parity = 0;
int code_cols = 0;
int comb_cols = 0;
int comb_dist = 1;
@ -266,6 +268,8 @@ struct Encoder
code_order = 12;
code_cols = 256;
data_bits = 2048;
parity_stride = 31;
first_parity = 3;
reserved_tones = 0;
frozen_bits = frozen_4096_2147;
break;
@ -276,6 +280,8 @@ struct Encoder
code_order = 13;
code_cols = 256;
data_bits = 4096;
parity_stride = 31;
first_parity = 5;
reserved_tones = 0;
frozen_bits = frozen_8192_4261;
break;
@ -286,6 +292,8 @@ struct Encoder
code_order = 14;
code_cols = 256;
data_bits = 8192;
parity_stride = 31;
first_parity = 9;
reserved_tones = 0;
frozen_bits = frozen_16384_8489;
break;
@ -296,6 +304,8 @@ struct Encoder
code_order = 12;
code_cols = 256;
data_bits = 2048;
parity_stride = 31;
first_parity = 3;
reserved_tones = 8;
frozen_bits = frozen_4096_2147;
break;
@ -306,6 +316,8 @@ struct Encoder
code_order = 13;
code_cols = 256;
data_bits = 4096;
parity_stride = 31;
first_parity = 5;
reserved_tones = 8;
frozen_bits = frozen_8192_4261;
break;
@ -316,6 +328,8 @@ struct Encoder
code_order = 14;
code_cols = 256;
data_bits = 8192;
parity_stride = 31;
first_parity = 9;
reserved_tones = 8;
frozen_bits = frozen_16384_8489;
break;
@ -326,6 +340,8 @@ struct Encoder
code_order = 13;
code_cols = 273;
data_bits = 4096;
parity_stride = 31;
first_parity = 5;
reserved_tones = 15;
frozen_bits = frozen_8192_4261;
break;
@ -336,6 +352,8 @@ struct Encoder
code_order = 14;
code_cols = 273;
data_bits = 8192;
parity_stride = 31;
first_parity = 9;
reserved_tones = 15;
frozen_bits = frozen_16384_8489;
break;
@ -372,7 +390,7 @@ struct Encoder
crc1(inp[i]);
for (int i = 0; i < 32; ++i)
mesg[i+data_bits] = nrz((crc1()>>i)&1);
polarenc(code, mesg, frozen_bits, code_order, 31);
polarenc(code, mesg, frozen_bits, code_order, parity_stride, first_parity);
shuffle(code);
for (int i = 0; i < cons_cols; ++i)
prev[i] = fdom[bin(i+code_off)];