rpitx/ft8_lib
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

Removed unnecessary copying and memory use

Browse source
This commit is contained in:
Karlis Goba 2018-12-25 14:01:09 +02:00
parent e6cbd139ff
commit 70837f4cbc
1 changed files with 5 additions and 13 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

18
ft8/ldpc.cpp
View file

@ -50,21 +50,17 @@ void ldpc_decode(float codeword[], int max_iters, uint8_t plain[], int *ok) {
} }
} }
uint8_t cw[FT8_N];
for (int i = 0; i < FT8_N; i++) { for (int i = 0; i < FT8_N; i++) {
float l = codeword[i]; float l = codeword[i];
for (int j = 0; j < 3; j++) for (int j = 0; j < 3; j++)
l += e[kMn[i][j] - 1][i]; l += e[kMn[i][j] - 1][i];
cw[i] = (l > 0) ? 1 : 0; plain[i] = (l > 0) ? 1 : 0;
} }
int errors = ldpc_check(cw); int errors = ldpc_check(plain);
if (errors < min_errors) { if (errors < min_errors) {
// Update the current best result // Update the current best result
for (int i = 0; i < FT8_N; i++) {
plain[i] = cw[i];
}
min_errors = errors; min_errors = errors;
if (errors == 0) { if (errors == 0) {
@ -137,25 +133,21 @@ void bp_decode(float codeword[], int max_iters, uint8_t plain[], int *ok) {
for (int iter = 0; iter < max_iters; ++iter) { for (int iter = 0; iter < max_iters; ++iter) {
float zn[FT8_N]; float zn[FT8_N];
uint8_t cw[FT8_N];
// Update bit log likelihood ratios (tov=0 in iter 0) // Update bit log likelihood ratios (tov=0 in iter 0)
for (int i = 0; i < FT8_N; ++i) { for (int i = 0; i < FT8_N; ++i) {
zn[i] = codeword[i] + tov[i][0] + tov[i][1] + tov[i][2]; zn[i] = codeword[i] + tov[i][0] + tov[i][1] + tov[i][2];
cw[i] = (zn[i] > 0) ? 1 : 0; plain[i] = (zn[i] > 0) ? 1 : 0;
} }
// Check to see if we have a codeword (check before we do any iter) // Check to see if we have a codeword (check before we do any iter)
int errors = ldpc_check(cw); int errors = ldpc_check(plain);
if (errors < min_errors) { if (errors < min_errors) {
// we have a better guess - update the result // we have a better guess - update the result
for (int i = 0; i < FT8_N; i++) {
plain[i] = cw[i];
}
min_errors = errors; min_errors = errors;
if (errors == FT8_M) { if (errors == 0) {
break; // Found a perfect answer break; // Found a perfect answer
} }
} }