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m17-decoder-sym updates 

updated for the latest libm17
main
Wojciech Kaczmarski 2025-04-02 17:31:19 +02:00
rodzic 2f4064f10d
commit 527432a2ea
1 zmienionych plików z 32 dodań i 64 usunięć
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SP5WWP/m17-decoder/m17-decoder-sym.c
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@ -24,18 +24,15 @@ float sample; //last raw sample from the stdin
float last[8]; //look-back buffer for finding syncwords float last[8]; //look-back buffer for finding syncwords
float dist; //Euclidean distance for finding syncwords in the symbol stream float dist; //Euclidean distance for finding syncwords in the symbol stream
float pld[SYM_PER_PLD]; //raw frame symbols float pld[SYM_PER_PLD]; //raw frame symbols
uint16_t soft_bit[2*SYM_PER_PLD]; //raw frame soft bits
uint16_t d_soft_bit[2*SYM_PER_PLD]; //deinterleaved soft bits
uint8_t lsf[30+1]; //complete LSF (one byte extra needed for the Viterbi decoder) lsf_t lsf; //complete LSF
uint16_t lich_chunk[96]; //raw, soft LSF chunk extracted from the LICH uint16_t lich_chunk[96]; //raw, soft LSF chunk extracted from the LICH
uint8_t lich_b[6]; //48-bit decoded LICH uint8_t lich_b[5]; //48-bit decoded LICH
uint8_t lich_cnt; //LICH_CNT uint8_t lich_cnt; //LICH_CNT
uint8_t lich_chunks_rcvd=0; //flags set for each LSF chunk received uint8_t lich_chunks_rcvd=0; //flags set for each LSF chunk received
uint16_t expected_next_fn=0; //frame number of the next frame expected to arrive uint16_t expected_next_fn=0; //frame number of the next frame expected to arrive
uint16_t enc_data[272]; //raw frame data soft bits uint8_t frame_data[16]; //decoded frame data, 128 bits
uint8_t frame_data[19]; //decoded frame data, 144 bits (16+128), plus 4 flushing bits
uint8_t syncd=0; //syncword found? uint8_t syncd=0; //syncword found?
uint8_t fl=0; //Frame=0 of LSF=1 uint8_t fl=0; //Frame=0 of LSF=1
@ -524,31 +521,16 @@ int main(int argc, char* argv[])
if(pushed==SYM_PER_PLD) if(pushed==SYM_PER_PLD)
{ {
//common operations for all frame types
//slice symbols to soft dibits
slice_symbols(soft_bit, pld);
//derandomize
randomize_soft_bits(soft_bit);
//deinterleave
reorder_soft_bits(d_soft_bit, soft_bit);
//if it is a frame //if it is a frame
if(!fl) if(!fl)
{ {
//extract data uint16_t fn;
for(uint16_t i=0; i<272; i++)
{
enc_data[i]=d_soft_bit[96+i];
}
//decode //decode
uint32_t e=viterbi_decode_punctured(frame_data, enc_data, puncture_pattern_2, 272, 12); uint32_t e = decode_str_frame(frame_data, lich_b, &fn, &lich_cnt, pld);
uint16_t fn = (frame_data[1] << 8) | frame_data[2]; uint16_t type = ((uint16_t)lsf.type[0]<<8)+lsf.type[1];
uint16_t type=(uint16_t)lsf[12]*0x100+lsf[13]; //big-endian signed_str = (type>>11)&1;
signed_str=(type>>11)&1;
///if the stream is signed (process before decryption) ///if the stream is signed (process before decryption)
if(signed_str && fn<0x7FFC) if(signed_str && fn<0x7FFC)
@ -557,7 +539,7 @@ int main(int argc, char* argv[])
memset(digest, 0, sizeof(digest)); memset(digest, 0, sizeof(digest));
for(uint8_t i=0; i<sizeof(digest); i++) for(uint8_t i=0; i<sizeof(digest); i++)
digest[i]^=frame_data[3+i]; digest[i]^=frame_data[i];
uint8_t tmp=digest[0]; uint8_t tmp=digest[0];
for(uint8_t i=0; i<sizeof(digest)-1; i++) for(uint8_t i=0; i<sizeof(digest)-1; i++)
digest[i]=digest[i+1]; digest[i]=digest[i+1];
@ -570,14 +552,14 @@ int main(int argc, char* argv[])
//AES //AES
if(encryption==ENCR_AES) if(encryption==ENCR_AES)
{ {
memcpy(iv, lsf+14, 14); memcpy(iv, lsf.meta, 14);
iv[14] = frame_data[1] & 0x7F; iv[14] = (fn>>8) & 0x7F; //TODO: check if this is the right byte order
iv[15] = frame_data[2] & 0xFF; iv[15] = (fn&0xFF) & 0xFF;
if(signed_str && (fn % 0x8000)<0x7FFC) //signed stream if(signed_str && (fn % 0x8000)<0x7FFC) //signed stream
aes_ctr_bytewise_payload_crypt(iv, key, frame_data+3, aes_subtype); aes_ctr_bytewise_payload_crypt(iv, key, frame_data, aes_subtype);
else if(!signed_str) //non-signed stream else if(!signed_str) //non-signed stream
aes_ctr_bytewise_payload_crypt(iv, key, frame_data+3, aes_subtype); aes_ctr_bytewise_payload_crypt(iv, key, frame_data, aes_subtype);
} }
//Scrambler //Scrambler
@ -595,13 +577,13 @@ int main(int argc, char* argv[])
for(uint8_t i=0; i<16; i++) for(uint8_t i=0; i<16; i++)
{ {
frame_data[i+3] ^= scr_bytes[i]; frame_data[i] ^= scr_bytes[i];
} }
} }
//dump data - first byte is empty //dump data
printf("FN: %04X PLD: ", fn); printf("FN: %04X PLD: ", fn);
for(uint8_t i=3; i<19; i++) for(uint8_t i=0; i<16; i++)
{ {
printf("%02X", frame_data[i]); printf("%02X", frame_data[i]);
} }
@ -613,22 +595,12 @@ int main(int argc, char* argv[])
//send codec2 stream to stdout //send codec2 stream to stdout
//fwrite(&frame_data[3], 16, 1, stdout); //fwrite(&frame_data[3], 16, 1, stdout);
//extract LICH
for(uint16_t i=0; i<96; i++)
{
lich_chunk[i]=d_soft_bit[i];
}
//Golay decoder
decode_LICH(lich_b, lich_chunk);
lich_cnt=lich_b[5]>>5;
//If we're at the start of a superframe, or we missed a frame, reset the LICH state //If we're at the start of a superframe, or we missed a frame, reset the LICH state
if((lich_cnt==0) || ((fn % 0x8000)!=expected_next_fn && fn<0x7FFC)) if((lich_cnt==0) || ((fn % 0x8000)!=expected_next_fn && fn<0x7FFC))
lich_chunks_rcvd=0; lich_chunks_rcvd=0;
lich_chunks_rcvd|=(1<<lich_cnt); lich_chunks_rcvd|=(1<<lich_cnt);
memcpy(&lsf[lich_cnt*5], lich_b, 5); memcpy((uint8_t*)&lsf+lich_cnt*5, lich_b, 5);
//debug - dump LICH //debug - dump LICH
if(lich_chunks_rcvd==0x3F) //all 6 chunks received? if(lich_chunks_rcvd==0x3F) //all 6 chunks received?
@ -637,8 +609,8 @@ int main(int argc, char* argv[])
{ {
uint8_t d_dst[12], d_src[12]; //decoded strings uint8_t d_dst[12], d_src[12]; //decoded strings
decode_callsign_bytes(d_dst, &lsf[0]); decode_callsign_bytes(d_dst, lsf.dst);
decode_callsign_bytes(d_src, &lsf[6]); decode_callsign_bytes(d_src, lsf.src);
//DST //DST
printf("DST: %-9s ", d_dst); printf("DST: %-9s ", d_dst);
@ -651,13 +623,13 @@ int main(int argc, char* argv[])
//DST //DST
printf("DST: "); printf("DST: ");
for(uint8_t i=0; i<6; i++) for(uint8_t i=0; i<6; i++)
printf("%02X", lsf[i]); printf("%02X", ((uint8_t*)lsf.dst)[i]);
printf(" "); printf(" ");
//SRC //SRC
printf("SRC: "); printf("SRC: ");
for(uint8_t i=0; i<6; i++) for(uint8_t i=0; i<6; i++)
printf("%02X", lsf[6+i]); printf("%02X", ((uint8_t*)lsf.src)[i]);
printf(" "); printf(" ");
} }
@ -712,7 +684,7 @@ int main(int argc, char* argv[])
{ {
printf("META: "); printf("META: ");
for(uint8_t i=0; i<14; i++) for(uint8_t i=0; i<14; i++)
printf("%02X", lsf[14+i]); printf("%02X", ((uint8_t*)lsf.meta)[i]);
printf(" "); printf(" ");
} }
@ -722,7 +694,7 @@ int main(int argc, char* argv[])
//printf("CRC: "); //printf("CRC: ");
//for(uint8_t i=0; i<2; i++) //for(uint8_t i=0; i<2; i++)
//printf("%02X", lsf[28+i]); //printf("%02X", lsf[28+i]);
if(CRC_M17(lsf, 30)) if(CRC_M17((uint8_t*)&lsf, sizeof(lsf)))
printf("LSF_CRC_ERR"); printf("LSF_CRC_ERR");
else else
printf("LSF_CRC_OK"); printf("LSF_CRC_OK");
@ -733,7 +705,7 @@ int main(int argc, char* argv[])
//if the contents of the payload is now digital signature, not data/voice //if the contents of the payload is now digital signature, not data/voice
if(fn>=0x7FFC && signed_str) if(fn>=0x7FFC && signed_str)
{ {
memcpy(&sig[((fn&0x7FFF)-0x7FFC)*16], &frame_data[3], 16); memcpy(&sig[((fn&0x7FFF)-0x7FFC)*16], frame_data, 16);
if(fn==(0x7FFF|0x8000)) if(fn==(0x7FFF|0x8000))
{ {
@ -771,19 +743,15 @@ int main(int argc, char* argv[])
printf("{LSF} "); printf("{LSF} ");
//decode //decode
uint32_t e=viterbi_decode_punctured(lsf, d_soft_bit, puncture_pattern_1, 2*SYM_PER_PLD, 61); uint32_t e = decode_LSF(&lsf, pld);
//shift the buffer 1 position left - get rid of the encoded flushing bits
for(uint8_t i=0; i<30; i++)
lsf[i]=lsf[i+1];
//dump data //dump data
if(decode_callsigns) if(decode_callsigns)
{ {
uint8_t d_dst[12], d_src[12]; //decoded strings uint8_t d_dst[12], d_src[12]; //decoded strings
decode_callsign_bytes(d_dst, &lsf[0]); decode_callsign_bytes(d_dst, lsf.dst);
decode_callsign_bytes(d_src, &lsf[6]); decode_callsign_bytes(d_src, lsf.src);
//DST //DST
printf("DST: %-9s ", d_dst); printf("DST: %-9s ", d_dst);
@ -796,18 +764,18 @@ int main(int argc, char* argv[])
//DST //DST
printf("DST: "); printf("DST: ");
for(uint8_t i=0; i<6; i++) for(uint8_t i=0; i<6; i++)
printf("%02X", lsf[i]); printf("%02X", ((uint8_t*)lsf.dst)[i]);
printf(" "); printf(" ");
//SRC //SRC
printf("SRC: "); printf("SRC: ");
for(uint8_t i=0; i<6; i++) for(uint8_t i=0; i<6; i++)
printf("%02X", lsf[6+i]); printf("%02X", ((uint8_t*)lsf.src)[i]);
printf(" "); printf(" ");
} }
//TYPE //TYPE
uint16_t type=(uint16_t)lsf[12]*0x100+lsf[13]; //big-endian uint16_t type = ((uint16_t)lsf.type[0]<<8)+lsf.type[1];
printf("TYPE: %04X (", type); printf("TYPE: %04X (", type);
if(type&&1) if(type&&1)
printf("STREAM: "); printf("STREAM: ");
@ -861,7 +829,7 @@ int main(int argc, char* argv[])
{ {
printf("META: "); printf("META: ");
for(uint8_t i=0; i<14; i++) for(uint8_t i=0; i<14; i++)
printf("%02X", lsf[14+i]); printf("%02X", ((uint8_t*)lsf.meta)[i]);
printf(" "); printf(" ");
} }
@ -871,7 +839,7 @@ int main(int argc, char* argv[])
//printf("CRC: "); //printf("CRC: ");
//for(uint8_t i=0; i<2; i++) //for(uint8_t i=0; i<2; i++)
//printf("%02X", lsf[28+i]); //printf("%02X", lsf[28+i]);
if(CRC_M17(lsf, 30)) if(CRC_M17((uint8_t*)&lsf, 30))
printf("LSF_CRC_ERR"); printf("LSF_CRC_ERR");
else else
printf("LSF_CRC_OK"); printf("LSF_CRC_OK");