/* * compile: * gcc dft_detect.c -lm -o dft_detect * speedup: * gcc -Ofast dft_detect.c -lm -o dft_detect * * author: zilog80 */ #include #include #include #include #include #ifndef M_PI #define M_PI (3.1415926535897932384626433832795) #endif typedef unsigned char ui8_t; typedef unsigned short ui16_t; typedef unsigned int ui32_t; typedef short i16_t; typedef int i32_t; static int option_verbose = 0, // ausfuehrliche Anzeige option_inv = 0, // invertiert Signal option_min = 0, option_iq = 0, option_dc = 0, option_silent = 0, option_cont = 0, option_d2 = 0, option_pcmraw = 0, option_singleLpIQ = 0, wavloaded = 0; static int wav_channel = 0; // audio channel: left //int dfm_sps = 2500; static char dfm_header[] = "10011010100110010101101001010101"; // DFM-09 // "01100101011001101010010110101010"; // DFM-06 //int vai_sps = 4800; static char rs41_header[] = "00001000011011010101001110001000" "01000100011010010100100000011111"; static char rs92_header[] = //"10100110011001101001" //"10100110011001101001" "10100110011001101001" "10100110011001101001" "1010011001100110100110101010100110101001"; //int lms_sps = 4800; // lms6_403MHz static char lms6_header[] = "0101011000001000""0001110010010111" "0001101010100111""0011110100111110"; //int mk2a_sps = 9600; // lms6_1680MHz static char mk2a_header[] = "0010100111""0010100111""0001001001""0010010101"; //int m10_sps = 9600; static char m10_header[] = //"10011001100110010100110010011001"; "1001100110010100110010011001""1010"; // ofs=4/2 in frm_M10() // frame byte[0..1]: byte[0]=framelen-1, byte[1]=type(8F=M2K2,9F=M10,AF=M10+,20=M20) // M2K2 : 64 8F : 01100100 10001111 // M10 : 64 9F : 01100100 10011111 (framelen 0x64+1) (baud=9616) // M10-aux: 76 9F : 01110110 10011111 (framelen 0x76+1) // M10+ : 64 AF : 01100100 10101111 (w/ gtop-GPS) // M20 : 45 20 : 01000101 00100000 (framelen 0x45+1) (baud=9600) //int meisei_sps = 2400; // 0xFB6230 = static char meisei_header[] = "110011001101001101001101010100101010110010101010"; // 11111011 01100010 00110000 //int mrz_sps = 2400; static char mrz_header[] = "1001100110011001""1001101010101010"; // 0xAA 0xBF //int imet54_sps = 4800; static char imet54_header[] = "0000000001""0101010101""0001001001""0001001001"; // 0x00 0xAA 0x24 0x24 // Meteosis MTS01 1200 baud // Lmax // len(AA AA B4 2B)=32 -> L=1280 // more accurate, +19% slower // len(AA B4 2B)=24 -> L=960 // same L as meisei, +7% slower static char mts01_header[] = "10101010""10101010" // preamble: AA AA "10110100""00101011"; // 10000000: B4 2B //80 // imet_9600 / 1200 Hz; static char imet_preamble[] = //"11110000111100001111000011110000" //"11110000111100001111000011110000" "11110000111100001111000011110000" "11110000111100001111000011110000"; // 1200 Hz 0xAA 0xAA preamble //int imet1ab_sps = 9600; // 1200 bits/sec // AFSK 1200/2400 static char imet1ab_header[] = "0000""11110000111100001111000011110000""1111" // idle //"0000""10101100110010101100101010101100""1111" "0000""10101100110010101100101010101100""1111"; // 0x96 // 11110000:1 , 001100110:0 // 11/4=2.1818.. static char imet1rs_header[] = "0000""1111""0000""1111""0000""1111" // preamble "0000""1111"; // imet1rs/imet4 1200Hz preamble , lead_out , 8N1 byte: lead-in 8bits lead-out , ... // 1:1200Hz/0:2200Hz tones, bit-duration 1/1200 sec, phase ... // bits: 1111111111111111111 10 10000000 10 ..; // C34/C50: 2400 baud, 1:2900Hz/0:4800Hz static char c34_preheader[] = "01010101010101010101010101010101"; // 2900 Hz tone // dft, dB-max(1000Hz..5000Hz) = 2900Hz ? static char weathex_header[] = "10101010""10101010""10101010" // AA AA AA (preamble) "00101101""11010100"; //"10101010"; // 2D D4 55/AA typedef struct { int sps; // header: symbol rate, baud int hLen; int L; char *header; float BT; float spb; float thres; int herrs; float complex *Fm; char *type; int tn; int lpFM; int lpIQ; float dc; float df; // Df = df*sr_base; } rsheader_t; #define N_bwIQ 4 static float lpFM_bw[2] = { 4e3, 10e3 }; // FM-audio lowpass bandwidth static float lpIQ_bw[N_bwIQ] = { 6e3, 12e3, 22e3, 200e3 }; // IF iq lowpass bandwidth static float set_lpIQ = 0.0; #define tn_DFM 2 #define tn_RS41 3 #define tn_RS92 4 #define tn_M10 5 #define tn_M20 6 #define tn_LMS6 8 #define tn_MEISEI 9 #define tn_MRZ 12 #define tn_MTS01 13 #define tn_C34C50 15 #define tn_WXR301 16 #define tn_MK2LMS 18 #define tn_IMET5 24 #define tn_IMETa 25 #define tn_IMET4 26 #define tn_IMET1rs 28 #define tn_IMET1ab 29 #define Nrs 16 #define idxIMETafsk 13 #define idxRS 14 #define idxI4 15 static rsheader_t rs_hdr[Nrs] = { { 2500, 0, 0, dfm_header, 1.0, 0.0, 0.65, 2, NULL, "DFM9", tn_DFM, 0, 1, 0.0, 0.0}, // DFM6: -2 ? { 4800, 0, 0, rs41_header, 0.5, 0.0, 0.70, 2, NULL, "RS41", tn_RS41, 0, 1, 0.0, 0.0}, { 4800, 0, 0, rs92_header, 0.5, 0.0, 0.70, 3, NULL, "RS92", tn_RS92, 0, 1, 0.0, 0.0}, // RS92NGP: 1680/400=4.2 { 4800, 0, 0, lms6_header, 1.0, 0.0, 0.60, 8, NULL, "LMS6", tn_LMS6, 0, 1, 0.0, 0.0}, // lmsX: 7? { 4800, 0, 0, imet54_header, 0.5, 0.0, 0.80, 2, NULL, "IMET5", tn_IMET5, 0, 1, 0.0, 0.0}, // (rs_hdr[idxI5]) { 9616, 0, 0, mk2a_header, 1.0, 0.0, 0.70, 2, NULL, "MK2LMS", tn_MK2LMS, 1, 2, 0.0, 0.0}, // Mk2a/LMS6-1680 , --IQ: decimate > 170kHz ... { 9608, 0, 0, m10_header, 1.0, 0.0, 0.76, 2, NULL, "M10", tn_M10, 1, 2, 0.0, 0.0}, // M10.tn=5 (baud=9616) , M20.tn=6 (baud=9600) { 2400, 0, 0, meisei_header, 1.0, 0.0, 0.70, 2, NULL, "MEISEI", tn_MEISEI, 0, 2, 0.0, 0.0}, { 2400, 0, 0, mrz_header, 1.5, 0.0, 0.80, 2, NULL, "MRZ", tn_MRZ, 0, 1, 0.0, 0.0}, { 1200, 0, 0, mts01_header, 1.0, 0.0, 0.65, 2, NULL, "MTS01", tn_MTS01, 0, 0, 0.0, 0.0}, { 5800, 0, 0, c34_preheader, 1.5, 0.0, 0.80, 2, NULL, "C34C50", tn_C34C50, 0, 2, 0.0, 0.0}, // C34/C50 2900 Hz tone { 4800, 0, 0, weathex_header, 1.0, 0.0, 0.65, 2, NULL, "WXR301", tn_WXR301, 0, 3, 0.0, 0.0}, { 9600, 0, 0, imet1ab_header, 1.0, 0.0, 0.80, 2, NULL, "IMET1AB", tn_IMET1ab, 1, 3, 0.0, 0.0}, // (rs_hdr[idxAB]) { 9600, 0, 0, imet_preamble, 0.5, 0.0, 0.80, 4, NULL, "IMETafsk", tn_IMETa , 1, 1, 0.0, 0.0}, // IMET1AB, IMET1RS (IQ)IMET4 { 9600, 0, 0, imet1rs_header, 0.5, 0.0, 0.80, 2, NULL, "IMET1RS", tn_IMET1rs, 0, 3, 0.0, 0.0}, // (rs_hdr[idxRS]) IMET4: lpIQ=0 ... { 9600, 0, 0, imet1rs_header, 0.5, 0.0, 0.80, 2, NULL, "IMET4", tn_IMET4, 1, 1, 0.0, 0.0}, // (rs_hdr[idxI4]) }; static int idx_MTS01 = -1, idx_C34C50 = -1, idx_WXR301 = -1, idx_IMET1AB = -1; static int rs_detect2[Nrs]; static int rs_d2() { int tn = 0; for (tn = 0; tn < Nrs; tn++) { if ( rs_detect2[tn] > 1 ) break; } return tn; } static int reset_d2() { int n = 0; for (n = 0; n < Nrs; n++) rs_detect2[n] = 0; return 0; } /* // m10-false-positive: // m10-preamble similar to rs41-preamble, parts of rs92/imet1ab, imet1ab; diffs: // - iq: - modulation-index rs41 < rs92 < m10, // - power level / frame < 1s, noise // - fm: - frame duration <-> noise (variance/standard deviation) // - pulse-shaping // m10: 00110011 at 9600 sps // rs41: 0 1 0 1 at 4800 sps // - after header, m10-baudrate < rs41-baudrate // - m10 top-carrier, fm-mean/average // - m10-header ..110(1)0110011()011.. bit shuffle // - m10 frame byte[1]=type(M2K2,M10,M10+) */ /* // rs92 // imet1ab-false-positive // ... */ #define FM_GAIN (0.8) static int sr_base = 0; static int sr_if = 0; static int sample_rate = 0, bits_sample = 0, channels = 0; static int wav_ch = 0; // 0: links bzw. mono; 1: rechts static ui32_t sample_in, sample_out, delay; static int M; static float *buf_fm[N_bwIQ]; static float *bufs = NULL; static char *rawbits = NULL; /* ------------------------------------------------------------------------------------ */ // decimation static ui32_t dsp__sr_base; static ui32_t dsp__dectaps; static ui32_t dsp__sample_decX; static int dsp__decM = 1; static float complex *dsp__decXbuffer; static float complex *dsp__decMbuf; static float complex *dsp__ex; // exp_lut static ui32_t dsp__lut_len; static ui32_t dsp__sample_decM; static float *ws_dec; static double dsp__xlt_fq = 0.0; static int LOG2N, N_DFT; static float complex *ew; static float complex *X, *Z, *cx; static float *xn; static float *db; // FM: lowpass static float *ws_lpFM[2]; static int dsp__lpFMtaps; // ui32_t static float complex *Y; static float complex *WS[2]; // IF: lowpass static float *ws_lpIQ[N_bwIQ]; // only N_bwIQ-1 used static int dsp__lpIQtaps; // ui32_t static float complex *lpIQ_buf; static void dft_raw(float complex *Z) { int s, l, l2, i, j, k; float complex w1, w2, T; j = 1; for (i = 1; i < N_DFT; i++) { if (i < j) { T = Z[j-1]; Z[j-1] = Z[i-1]; Z[i-1] = T; } k = N_DFT/2; while (k < j) { j = j - k; k = k/2; } j = j + k; } for (s = 0; s < LOG2N; s++) { l2 = 1 << s; l = l2 << 1; w1 = (float complex)1.0; w2 = ew[s]; // cexp(-I*M_PI/(float)l2) for (j = 1; j <= l2; j++) { for (i = j; i <= N_DFT; i += l) { k = i + l2; T = Z[k-1] * w1; Z[k-1] = Z[i-1] - T; Z[i-1] = Z[i-1] + T; } w1 = w1 * w2; } } } static void dft(float *x, float complex *Z) { int i; for (i = 0; i < N_DFT; i++) Z[i] = (float complex)x[i]; dft_raw(Z); } static void Nidft(float complex *Z, float complex *z) { int i; for (i = 0; i < N_DFT; i++) z[i] = conj(Z[i]); dft_raw(z); // idft(): // for (i = 0; i < N_DFT; i++) z[i] = conj(z[i])/(float)N_DFT; // hier: z reell } static float freq2bin(int f) { return f * N_DFT / (float)sample_rate; } static float bin2freq(int k) { float fq = k / (float)N_DFT; if ( fq >= 0.5) fq -= 1.0; return fq*sample_rate; } /* ------------------------------------------------------------------------------------ */ static int getCorrDFT(int K, unsigned int pos, float *maxv, unsigned int *maxvpos, rsheader_t *rshd) { int i; int mp = -1; float mx = 0.0; float mx2 = 0.0; float re_cx = 0.0; double xnorm = 1.0; unsigned int mpos = 0; float dc = 0.0; rshd->dc = 0.0; if (K + rshd->L > N_DFT) return -1; // if (sample_out < rshd->L) return -2; // nur falls K-4 < L if (pos == 0) pos = sample_out; bufs = buf_fm[rshd->lpIQ]; for (i = 0; i < K+rshd->L; i++) xn[i] = bufs[(pos+M -(K+rshd->L-1) + i) % M]; while (i < N_DFT) xn[i++] = 0.0; dft(xn, X); //dc = get_bufmu(pos-sample_out); //oder: dc = creal(X[0])/(K+rshd->L) = avg(xn) // zu lang (M10) dc = 0.0; if (option_dc) { //X[0] = 0; // all samples in window // L < K for (i=K-rshd->L; iL;i++) dc += xn[i]; // only last 2L samples (avoid M10 carrier offset) dc /= 2.0*(float)rshd->L; X[0] -= N_DFT*dc * 0.98; } rshd->dc = dc; if (option_iq) { // FM-lowpass(xn) for (i = 0; i < N_DFT; i++) X[i] *= WS[rshd->lpFM][i]; } if (option_dc || option_iq) { // mx = mx(xn[]), xn(lowpass, dc) Nidft(X, cx); for (i = 0; i < N_DFT; i++) xn[i] = creal(cx[i])/(float)N_DFT; } for (i = 0; i < N_DFT; i++) Z[i] = X[i] * rshd->Fm[i]; Nidft(Z, cx); // relativ Peak - Normierung erst zum Schluss; // dann jedoch nicht zwingend corr-Max wenn FM-Amplitude bzw. norm(x) nicht konstant // (z.B. rs41 Signal-Pausen). Moeglicherweise wird dann wahres corr-Max in dem // K-Fenster nicht erkannt, deshalb K nicht zu gross waehlen. // mx2 = 0.0; // t = L-1 for (i = rshd->L-1; i < K+rshd->L; i++) { // i=t .. i=t+K < t+1+K re_cx = creal(cx[i]); // imag(cx)=0 //if (fabs(re_cx) > fabs(mx)) { if (re_cx*re_cx > mx2) { mx = re_cx; mx2 = mx*mx; mp = i; } } if (mp == rshd->L-1 || mp == K+rshd->L-1) return -4; // Randwert // mp == t mp == K+t mpos = pos - (K + rshd->L-1) + mp; // t = L-1 xnorm = 0.0; for (i = 0; i < rshd->L; i++) xnorm += xn[mp-i]*xn[mp-i]; xnorm = sqrt(xnorm); mx /= xnorm*N_DFT; if (option_iq) mpos -= dsp__lpFMtaps/2; // lowpass delay *maxv = mx; *maxvpos = mpos; if (option_dc) { rshd->df = rshd->dc / (2.0*FM_GAIN*dsp__decM); // freq offset estimate } return mp; } /* ------------------------------------------------------------------------------------ */ static int findstr(char *buff, char *str, int pos) { int i; for (i = 0; i < 4; i++) { if (buff[(pos+i)%4] != str[i]) break; } return i; } static int read_wav_header(FILE *fp, int wav_channel) { char txt[4+1] = "\0\0\0\0"; unsigned char dat[4]; int byte, p=0; if (fread(txt, 1, 4, fp) < 4) return -1; if (strncmp(txt, "RIFF", 4) && strncmp(txt, "RF64", 4)) return -1; if (fread(txt, 1, 4, fp) < 4) return -1; // pos_WAVE = 8L if (fread(txt, 1, 4, fp) < 4) return -1; if (strncmp(txt, "WAVE", 4)) return -1; // pos_fmt = 12L for ( ; ; ) { if ( (byte=fgetc(fp)) == EOF ) return -1; txt[p % 4] = byte; p++; if (p==4) p=0; if (findstr(txt, "fmt ", p) == 4) break; } if (fread(dat, 1, 4, fp) < 4) return -1; if (fread(dat, 1, 2, fp) < 2) return -1; if (fread(dat, 1, 2, fp) < 2) return -1; channels = dat[0] + (dat[1] << 8); if (fread(dat, 1, 4, fp) < 4) return -1; memcpy(&sample_rate, dat, 4); //sample_rate = dat[0]|(dat[1]<<8)|(dat[2]<<16)|(dat[3]<<24); if (fread(dat, 1, 4, fp) < 4) return -1; if (fread(dat, 1, 2, fp) < 2) return -1; //byte = dat[0] + (dat[1] << 8); if (fread(dat, 1, 2, fp) < 2) return -1; bits_sample = dat[0] + (dat[1] << 8); // pos_dat = 36L + info for ( ; ; ) { if ( (byte=fgetc(fp)) == EOF ) return -1; txt[p % 4] = byte; p++; if (p==4) p=0; if (findstr(txt, "data", p) == 4) break; } if (fread(dat, 1, 4, fp) < 4) return -1; fprintf(stderr, "sample_rate: %d\n", sample_rate); fprintf(stderr, "bits : %d\n", bits_sample); fprintf(stderr, "channels : %d\n", channels); if (wav_channel >= 0 && wav_channel < channels) wav_ch = wav_channel; else wav_ch = 0; //fprintf(stderr, "channel-In : %d\n", wav_ch+1); if (bits_sample != 8 && bits_sample != 16 && bits_sample != 32) return -1; if (sample_rate == 900001) sample_rate -= 1; return 0; } static int f32read_sample(FILE *fp, float *s) { int i; unsigned int word = 0; short *b = (short*)&word; float *f = (float*)&word; for (i = 0; i < channels; i++) { if (fread( &word, bits_sample/8, 1, fp) != 1) return EOF; if (i == wav_ch) { // i = 0: links bzw. mono //if (bits_sample == 8) sint = b-128; // 8bit: 00..FF, centerpoint 0x80=128 //if (bits_sample == 16) sint = (short)b; if (bits_sample == 32) { *s = *f; } else { if (bits_sample == 8) { *b -= 128; } *s = *b/128.0; if (bits_sample == 16) { *s /= 256.0; } } } } return 0; } // IQ-dc typedef struct { double sumIQx; double sumIQy; float avgIQx; float avgIQy; ui32_t cnt; ui32_t maxcnt; } iq_dc_t; static iq_dc_t IQdc; static int f32read_csample(FILE *fp, float complex *z) { float x, y; if (bits_sample == 32) { //float32 float f[2]; if (fread( f, bits_sample/8, 2, fp) != 2) return EOF; x = f[0]; y = f[1]; } else if (bits_sample == 16) { //int16 short b[2]; if (fread( b, bits_sample/8, 2, fp) != 2) return EOF; x = b[0]/32768.0; y = b[1]/32768.0; } else { // bits_sample == 8 //uint8 ui8_t u[2]; if (fread( u, bits_sample/8, 2, fp) != 2) return EOF; x = (u[0]-128)/128.0; y = (u[1]-128)/128.0; } *z = (x - IQdc.avgIQx) + I*(y - IQdc.avgIQy); IQdc.sumIQx += x; IQdc.sumIQy += y; IQdc.cnt += 1; if (IQdc.cnt == IQdc.maxcnt) { IQdc.avgIQx = IQdc.sumIQx/(float)IQdc.maxcnt; IQdc.avgIQy = IQdc.sumIQy/(float)IQdc.maxcnt; IQdc.sumIQx = 0; IQdc.sumIQy = 0; IQdc.cnt = 0; } return 0; } static int f32read_cblock(FILE *fp) { int n; int len; float x, y; len = dsp__decM; if (bits_sample == 8) { //uint8 ui8_t u[2*dsp__decM]; len = fread( u, bits_sample/8, 2*dsp__decM, fp) / 2; //for (n = 0; n < len; n++) dsp__decMbuf[n] = (u[2*n]-128)/128.0 + I*(u[2*n+1]-128)/128.0; // u8: 0..255, 128 -> 0V for (n = 0; n < len; n++) { x = (u[2*n ]-128)/128.0; y = (u[2*n+1]-128)/128.0; dsp__decMbuf[n] = (x-IQdc.avgIQx) + I*(y-IQdc.avgIQy); IQdc.sumIQx += x; IQdc.sumIQy += y; IQdc.cnt += 1; if (IQdc.cnt == IQdc.maxcnt) { IQdc.avgIQx = IQdc.sumIQx/(float)IQdc.maxcnt; IQdc.avgIQy = IQdc.sumIQy/(float)IQdc.maxcnt; IQdc.sumIQx = 0; IQdc.sumIQy = 0; IQdc.cnt = 0; } } } else if (bits_sample == 16) { //int16 short b[2*dsp__decM]; len = fread( b, bits_sample/8, 2*dsp__decM, fp) / 2; for (n = 0; n < len; n++) { x = b[2*n ]/32768.0; y = b[2*n+1]/32768.0; dsp__decMbuf[n] = (x-IQdc.avgIQx) + I*(y-IQdc.avgIQy); IQdc.sumIQx += x; IQdc.sumIQy += y; IQdc.cnt += 1; if (IQdc.cnt == IQdc.maxcnt) { IQdc.avgIQx = IQdc.sumIQx/(float)IQdc.maxcnt; IQdc.avgIQy = IQdc.sumIQy/(float)IQdc.maxcnt; IQdc.sumIQx = 0; IQdc.sumIQy = 0; IQdc.cnt = 0; } } } else { // bits_sample == 32 //float32 float f[2*dsp__decM]; len = fread( f, bits_sample/8, 2*dsp__decM, fp) / 2; for (n = 0; n < len; n++) { x = f[2*n]; y = f[2*n+1]; dsp__decMbuf[n] = (x-IQdc.avgIQx) + I*(y-IQdc.avgIQy); IQdc.sumIQx += x; IQdc.sumIQy += y; IQdc.cnt += 1; if (IQdc.cnt == IQdc.maxcnt) { IQdc.avgIQx = IQdc.sumIQx/(float)IQdc.maxcnt; IQdc.avgIQy = IQdc.sumIQy/(float)IQdc.maxcnt; IQdc.sumIQx = 0; IQdc.sumIQy = 0; IQdc.cnt = 0; } } } return len; } static double sinc(double x) { double y; if (x == 0) y = 1; else y = sin(M_PI*x)/(M_PI*x); return y; } static int lowpass_init(float f, int taps, float **pws) { double *h, *w; double norm = 0; int n; float *ws = NULL; if (taps % 2 == 0) taps++; // odd/symmetric if ( taps < 1 ) taps = 1; h = (double*)calloc( taps+1, sizeof(double)); if (h == NULL) return -1; w = (double*)calloc( taps+1, sizeof(double)); if (w == NULL) return -1; ws = (float*)calloc( 2*taps+1, sizeof(float)); if (ws == NULL) return -1; for (n = 0; n < taps; n++) { w[n] = 7938/18608.0 - 9240/18608.0*cos(2*M_PI*n/(taps-1)) + 1430/18608.0*cos(4*M_PI*n/(taps-1)); // Blackmann h[n] = 2*f*sinc(2*f*(n-(taps-1)/2)); ws[n] = w[n]*h[n]; norm += ws[n]; // 1-norm } for (n = 0; n < taps; n++) { ws[n] /= norm; // 1-norm } for (n = 0; n < taps; n++) ws[taps+n] = ws[n]; // duplicate/unwrap *pws = ws; free(h); h = NULL; free(w); w = NULL; return taps; } // struct { int taps; double *ws} static float complex lowpass0(float complex buffer[], ui32_t sample, ui32_t taps, float *ws) { ui32_t n; double complex w = 0; for (n = 0; n < taps; n++) { w += buffer[(sample+n)%taps]*ws[taps-1-n]; } return (float complex)w; } //static __attribute__((optimize("-ffast-math"))) float complex lowpass() static float complex lowpass(float complex buffer[], ui32_t sample, ui32_t taps, float *ws) { float complex w = 0; int n; // -Ofast int S = taps - (sample % taps); for (n = 0; n < taps; n++) { w += buffer[n]*ws[S+n]; // ws[taps+s-n] = ws[(taps+sample-n)%taps] } return w; // symmetry: ws[n] == ws[taps-1-n] } static float complex lowpass2(float complex buffer[], ui32_t sample, ui32_t taps, float *ws) { float complex w = 0; int n; int s = sample % taps; int S1 = s; int S1N = S1-taps; int n0 = taps-s; for (n = 0; n < n0; n++) { w += buffer[S1+n]*ws[n]; } for (n = n0; n < taps; n++) { w += buffer[S1N+n]*ws[n]; } return w; // symmetry: ws[n] == ws[taps-1-n] } static int f32buf_sample(FILE *fp, int inv) { float _s = 0.0; float s[N_bwIQ]; static float complex z0_fm0; static float complex z0_fm1; static float complex z0_fm2; static float complex z0; float complex z_fm0=0, z_fm1=0, z_fm2=0; float complex z, w; double gain = FM_GAIN; int i; if (option_iq) { if (option_iq == 5) { // baseband decimation //ui32_t s_reset = dsp__dectaps*dsp__lut_len; int j; if ( f32read_cblock(fp) < dsp__decM ) return EOF; for (j = 0; j < dsp__decM; j++) { dsp__decXbuffer[dsp__sample_decX] = dsp__decMbuf[j] * dsp__ex[dsp__sample_decM]; dsp__sample_decM += 1; if (dsp__sample_decM >= dsp__lut_len) dsp__sample_decM = 0; dsp__sample_decX += 1; if (dsp__sample_decX >= dsp__dectaps) dsp__sample_decX = 0; } z = lowpass(dsp__decXbuffer, dsp__sample_decX, dsp__dectaps, ws_dec); } else if ( f32read_csample(fp, &z) == EOF ) return EOF; // IF-lowpass // a) detect signal bandwidth/center-fq (not reliable), or // b) N_bwIQ FM-streams // lpIQ_buf[sample_in % dsp__lpIQtaps] = z; z_fm0 = lowpass(lpIQ_buf, sample_in+1, dsp__lpIQtaps, ws_lpIQ[0]); if (option_singleLpIQ) { z_fm1 = z_fm0; z_fm2 = z_fm0; } else { z_fm1 = lowpass(lpIQ_buf, sample_in+1, dsp__lpIQtaps, ws_lpIQ[1]); z_fm2 = lowpass(lpIQ_buf, sample_in+1, dsp__lpIQtaps, ws_lpIQ[2]); } // IQ: different modulation indices h=h(rs) -> FM-demod w = z_fm0 * conj(z0_fm0); s[0] = gain * carg(w)/M_PI; z0_fm0 = z_fm0; if (option_singleLpIQ) { s[1] = s[0]; z0_fm1 = z_fm1; s[2] = s[0]; z0_fm2 = z_fm2; } else { w = z_fm1 * conj(z0_fm1); s[1] = gain * carg(w)/M_PI; z0_fm1 = z_fm1; w = z_fm2 * conj(z0_fm2); s[2] = gain * carg(w)/M_PI; z0_fm2 = z_fm2; } w = z * conj(z0); s[3] = gain * carg(w)/M_PI; z0 = z; } else { if (f32read_sample(fp, &_s) == EOF) return EOF; for (i = 0; i < N_bwIQ; i++) s[i] = _s; } for (i = 0; i < N_bwIQ; i++) { if (inv) s[i]= -s[i]; buf_fm[i][sample_in % M] = s[i]; } sample_out = sample_in - delay; sample_in += 1; return 0; } static int read_bufbit(int symlen, char *bits, unsigned int mvp, int reset, float dc, rsheader_t *rshd) { // symlen==2: manchester2 0->10,1->01->1: 2.bit static unsigned int rcount; static float rbitgrenze; double sum = 0.0; bufs = buf_fm[rshd->lpIQ]; if (reset) { rcount = 0; rbitgrenze = 0; } // bei symlen=2 (Manchester) kein dc noetig, // allerdings M10-header mit symlen=1 rbitgrenze += rshd->spb; do { sum += bufs[(rcount + mvp + M) % M] - dc; rcount++; } while (rcount < rbitgrenze); // n < spb if (symlen == 2) { rbitgrenze += rshd->spb; do { sum -= bufs[(rcount + mvp + M) % M] - dc; rcount++; } while (rcount < rbitgrenze); // n < spb } if (symlen != 2) { if (sum >= 0) *bits = '1'; else *bits = '0'; } else { if (sum >= 0) strncpy(bits, "10", 2); else strncpy(bits, "01", 2); } return 0; } static int headcmp(int symlen, unsigned int mvp, int inv, rsheader_t *rshd) { int errs = 0; int pos; int step = 1; int len = 0; char sign = 0; float dc = 0.0; if (option_dc) { /* len = rshd->L; for (pos = 0; pos < len; pos++) { dc += (double)bufs[(mvp - 1 - pos + M) % M]; } dc /= (double)len; */ dc = rshd->dc; } if (symlen != 1) step = 2; if (inv) sign=1; len = rshd->hLen; for (pos = 0; pos < len; pos += step) { read_bufbit(symlen, rawbits+pos, mvp+1-(int)(rshd->hLen*rshd->spb), pos==0, dc, rshd); } rawbits[pos] = '\0'; while (len > 0) { if ((rawbits[len-1]^sign) != rshd->header[len-1]) errs += 1; len--; } return errs; } static ui8_t bits2byte(char *bitstr) { int i, bit, d, byteval; int bitpos; bitpos = 0; byteval = 0; d = 1; for (i = 0; i < 8; i++) { //bit=*(bitstr+bitpos+i); /* little endian */ bit=*(bitstr+bitpos+7-i); /* big endian */ if (bit == '1') byteval += d; else /*if ((bit == '0')*/ byteval += 0; d <<= 1; } return byteval & 0xFF; } static int hw(ui8_t byte) { int i; int d = 0; for (i = 0; i < 8; i++) { d += (byte & 1); byte >>= 1; } return d; } static ui32_t frm_M10(unsigned int mvp, int inv, rsheader_t *rshd) { float dc = 0.0; int pos2; char bit0 = '0'; char mb[2]; char frmbit[16+1]; ui8_t b[2]; ui32_t bytes; int ofs = (strlen(rshd->header) - 28)/2; if (ofs < 0 || ofs > 8) ofs = 0; if (option_dc) dc = rshd->dc; bit0 = 0x30 + (inv > 0); for (pos2 = 0; pos2 < 16; pos2 += 1) { if (pos2 < ofs) { mb[0] = rshd->header[28+2*pos2] ^ (inv>0); } else { read_bufbit(2, mb, mvp, pos2==ofs, dc, rshd); } frmbit[pos2] = 0x31 ^ (bit0 ^ mb[0]); bit0 = mb[0]; } frmbit[pos2] = '\0'; b[0] = bits2byte(frmbit); b[1] = bits2byte(frmbit+8); bytes = (b[0]<<8) | b[1]; return bytes; } /* -------------------------------------------------------------------------- */ #define IF_SAMPLE_RATE 48000 #define IF_SAMPLE_RATE_MIN 32000 #define SQRT2 1.4142135624 // sqrt(2) // sigma = sqrt(log(2)) / (2*PI*BT): //#define SIGMA 0.2650103635 // BT=0.5: 0.2650103635 , BT=0.3: 0.4416839392 // Gaussian FM-pulse static double Q(double x) { return 0.5 - 0.5*erf(x/SQRT2); } static double pulse(double t, double sigma) { return Q((t-0.5)/sigma) - Q((t+0.5)/sigma); } static double norm2_match(float *match, int n) { int i; double x, y = 0.0; for (i = 0; i < n; i++) { x = match[i]; y += x*x; } return y; } static int init_buffers() { int i, j, pos; double t; double b0, b1, b2, b; float normMatch; int p2 = 1; int K, L; int n, k; float *match = NULL; float *m = NULL; double BT = 0.5; double sigma = sqrt(log(2)) / (2*M_PI*BT); char *bits = NULL; float spb = 0.0; int hLen = 0; int Lmax = 0; sr_base = sample_rate; sr_if = sample_rate; if (option_iq == 5) { int IF_sr = IF_SAMPLE_RATE; // designated IF sample rate int decM = 1; // decimate M:1 float f_lp; // dec_lowpass: lowpass_bw/2 float t_bw; // dec_lowpass: transition_bw int taps; // dec_lowpass: taps if (set_lpIQ > IF_sr) IF_sr = set_lpIQ; sr_base = sample_rate; if (option_min) IF_sr = IF_SAMPLE_RATE_MIN; if (IF_sr > sr_base) IF_sr = sr_base; if (IF_sr < sr_base) { while (sr_base % IF_sr) IF_sr += 1; decM = sr_base / IF_sr; } f_lp = (IF_sr+20e3)/(4.0*sr_base); t_bw = (IF_sr-20e3)/*/2.0*/; if (option_min) { t_bw = (IF_sr-12e3); } if (t_bw < 0) t_bw = 10e3; t_bw /= sr_base; taps = 4.0/t_bw; if (taps%2==0) taps++; taps = lowpass_init(f_lp, taps, &ws_dec); if (taps < 0) return -1; dsp__dectaps = taps; dsp__sr_base = sr_base; sample_rate = IF_sr; // sr_base/decM dsp__decM = decM; sr_if = IF_sr; fprintf(stderr, "IF: %d\n", IF_sr); fprintf(stderr, "dec: %d\n", decM); } if (option_iq == 5) { // look up table, exp-rotation int W = 2*8; // 16 Hz window int d = 1; // 1..W , groesster Teiler d <= W von sr_base int freq = (int)( dsp__xlt_fq * (double)dsp__sr_base + 0.5); int freq0 = freq; // init double f0 = freq0 / (double)dsp__sr_base; // init for (d = W; d > 0; d--) { // groesster Teiler d <= W von sr if (dsp__sr_base % d == 0) break; } if (d == 0) d = 1; // d >= 1 ? for (k = 0; k < W/2; k++) { if ((freq+k) % d == 0) { freq0 = freq + k; break; } if ((freq-k) % d == 0) { freq0 = freq - k; break; } } dsp__lut_len = dsp__sr_base / d; f0 = freq0 / (double)dsp__sr_base; dsp__ex = calloc(dsp__lut_len+1, sizeof(float complex)); if (dsp__ex == NULL) return -1; for (n = 0; n < dsp__lut_len; n++) { t = f0*(double)n; dsp__ex[n] = cexp(t*2*M_PI*I); } dsp__decXbuffer = calloc( dsp__dectaps+1, sizeof(float complex)); if (dsp__decXbuffer == NULL) return -1; dsp__decMbuf = calloc( dsp__decM+1, sizeof(float complex)); if (dsp__decMbuf == NULL) return -1; } if (option_iq) { float f_lp; // lowpass_bw int taps; // lowpass taps: 4*sr/transition_bw // FM lowpass -> xn[] in getCorrDFT() taps = 4*sample_rate/2e3; if (taps%2==0) taps++; // 2kHz transition // f_lp = lpFM_bw[0]/(float)sample_rate; // RS41,DFM: 4kHz (FM-audio) taps = lowpass_init(f_lp, taps, &ws_lpFM[0]); if (taps < 0) return -1; // f_lp = lpFM_bw[1]/(float)sample_rate; // M10: 10kHz (FM-audio) taps = lowpass_init(f_lp, taps, &ws_lpFM[1]); if (taps < 0) return -1; // dsp__lpFMtaps = taps; // IF lowpass taps = 4*sample_rate/4e3; if (taps%2==0) taps++; // 4kHz transition if (set_lpIQ > 100.0) { // set_lpIQ > 100Hz: overwrite lpIQ_bw[] lpIQ_bw[0] = set_lpIQ; lpIQ_bw[1] = set_lpIQ; lpIQ_bw[2] = set_lpIQ; option_singleLpIQ = 1; } // f_lp = lpIQ_bw[0]/(float)sample_rate/2.0; // MTS01: 6kHz (IF/IQ) taps = lowpass_init(f_lp, taps, &ws_lpIQ[0]); if (taps < 0) return -1; // f_lp = lpIQ_bw[1]/(float)sample_rate/2.0; // RS41,DFM: 12kHz (IF/IQ) taps = lowpass_init(f_lp, taps, &ws_lpIQ[1]); if (taps < 0) return -1; // f_lp = lpIQ_bw[2]/(float)sample_rate/2.0; // M10: 22kHz (IF/IQ) taps = lowpass_init(f_lp, taps, &ws_lpIQ[2]); if (taps < 0) return -1; // dsp__lpIQtaps = taps; lpIQ_buf = calloc( dsp__lpIQtaps+3, sizeof(float complex)); if (lpIQ_buf == NULL) return -1; } memset(&IQdc, 0, sizeof(IQdc)); IQdc.maxcnt = sample_rate/32; if (dsp__decM > 1) IQdc.maxcnt *= dsp__decM; for (j = 0; j < Nrs; j++) { #ifdef NOMTS01 if ( strncmp(rs_hdr[j].type, "MTS01", 5) == 0 ) idx_MTS01 = j; #endif #ifdef NOC34C50 if ( strncmp(rs_hdr[j].type, "C34C50", 6) == 0 ) idx_C34C50 = j; #endif #ifdef NOWXR301 if ( strncmp(rs_hdr[j].type, "WXR301", 5) == 0 ) idx_WXR301 = j; #endif #ifdef NOIMET1AB if ( strncmp(rs_hdr[j].type, "IMET1AB", 7) == 0 ) idx_IMET1AB = j; #endif } for (j = 0; j < Nrs; j++) { rs_hdr[j].spb = sample_rate/(float)rs_hdr[j].sps; rs_hdr[j].hLen = strlen(rs_hdr[j].header); rs_hdr[j].L = rs_hdr[j].hLen * rs_hdr[j].spb + 0.5; if (j != idx_MTS01 && j != idx_C34C50 && j != idx_WXR301 && j != idx_IMET1AB) { if (rs_hdr[j].hLen > hLen) hLen = rs_hdr[j].hLen; if (rs_hdr[j].L > Lmax) Lmax = rs_hdr[j].L; } } // L = hLen * sample_rate/2500.0 + 0.5; // max(hLen*spb) L = 2*Lmax; M = 3*L; //if (samples_per_bit < 6) M = 6*N; sample_in = 0; p2 = 1; while (p2 < M) p2 <<= 1; while (p2 < 0x2000) p2 <<= 1; // or 0x4000, if sample not too short N_DFT = p2; K = N_DFT - L; LOG2N = log(N_DFT)/log(2)+0.1; // 32bit cpu ... intermediate floating-point precision //while ((1 << LOG2N) < N_DFT) LOG2N++; // better N_DFT = (1 << LOG2N) ... delay = L/16; M = N_DFT + delay + 8; // L+K < M rawbits = (char *)calloc( hLen+1, sizeof(char)); if (rawbits == NULL) return -100; for (j = 0; j < N_bwIQ; j++) { buf_fm[j] = (float *)calloc( M+1, sizeof(float)); if (buf_fm[j] == NULL) return -100; } bufs = buf_fm[N_bwIQ-1]; xn = calloc(N_DFT+1, sizeof(float)); if (xn == NULL) return -1; db = calloc(N_DFT+1, sizeof(float)); if (db == NULL) return -1; ew = calloc(LOG2N+1, sizeof(float complex)); if (ew == NULL) return -1; X = calloc(N_DFT+1, sizeof(float complex)); if (X == NULL) return -1; Z = calloc(N_DFT+1, sizeof(float complex)); if (Z == NULL) return -1; cx = calloc(N_DFT+1, sizeof(float complex)); if (cx == NULL) return -1; for (n = 0; n < LOG2N; n++) { k = 1 << n; ew[n] = cexp(-I*M_PI/(float)k); } match = (float *)calloc( L+1, sizeof(float)); if (match == NULL) return -1; m = (float *)calloc(N_DFT+1, sizeof(float)); if (m == NULL) return -1; for (j = 0; j < idxRS; j++) { rs_hdr[j].Fm = (float complex *)calloc(N_DFT+1, sizeof(float complex)); if (rs_hdr[j].Fm == NULL) return -1; bits = rs_hdr[j].header; spb = rs_hdr[j].spb; sigma = sqrt(log(2)) / (2*M_PI*rs_hdr[j].BT); for (i = 0; i < rs_hdr[j].L; i++) { pos = i/spb; t = (i - pos*spb)/spb - 0.5; b1 = ((bits[pos] & 0x1) - 0.5)*2.0; b = b1*pulse(t, sigma); if (pos > 0) { b0 = ((bits[pos-1] & 0x1) - 0.5)*2.0; b += b0*pulse(t+1, sigma); } if (pos < hLen-1) { b2 = ((bits[pos+1] & 0x1) - 0.5)*2.0; b += b2*pulse(t-1, sigma); } match[i] = b; } normMatch = sqrt(norm2_match(match, rs_hdr[j].L)); for (i = 0; i < rs_hdr[j].L; i++) { match[i] /= normMatch; } for (i = 0; i < rs_hdr[j].L; i++) m[rs_hdr[j].L-1 - i] = match[i]; // t = L-1 while (i < N_DFT) m[i++] = 0.0; dft(m, rs_hdr[j].Fm); } if (option_iq) { for (j = 0; j < 2; j++) { WS[j] = (float complex *)calloc(N_DFT+1, sizeof(float complex)); if (WS[j] == NULL) return -1; for (i = 0; i < dsp__lpFMtaps; i++) m[i] = ws_lpFM[j][i]; while (i < N_DFT) m[i++] = 0.0; dft(m, WS[j]); } Y = (float complex *)calloc(N_DFT+1, sizeof(float complex)); if (Y == NULL) return -1; } free(match); match = NULL; free(m); m = NULL; return K; } static int free_buffers() { int j; for (j = 0; j < N_bwIQ; j++) { if (buf_fm[j]) { free(buf_fm[j]); buf_fm[j] = NULL; } } if (rawbits) { free(rawbits); rawbits = NULL; } if (xn) { free(xn); xn = NULL; } if (db) { free(xn); xn = NULL; } if (ew) { free(ew); ew = NULL; } if (X) { free(X); X = NULL; } if (Z) { free(Z); Z = NULL; } if (cx) { free(cx); cx = NULL; } for (j = 0; j < idxRS; j++) { if (rs_hdr[j].Fm) { free(rs_hdr[j].Fm); rs_hdr[j].Fm = NULL; } } // iq buffers if (option_iq == 5) { if (dsp__decXbuffer) { free(dsp__decXbuffer); dsp__decXbuffer = NULL; } if (dsp__decMbuf) { free(dsp__decMbuf); dsp__decMbuf = NULL; } if (dsp__ex) { free(dsp__ex); dsp__ex = NULL; } } if (option_iq) { for (j = 0; j < 2; j++) { if (ws_lpFM[j]) { free(ws_lpFM[j]); ws_lpFM[j] = NULL; } if (WS[j]) { free(WS[j]); WS[j] = NULL; } } if (Y) { free(Y); Y = NULL; } for (j = 0; j < N_bwIQ-1; j++) { if (ws_lpIQ[j]) { free(ws_lpIQ[j]); ws_lpIQ[j] = NULL; } } if (lpIQ_buf) { free(lpIQ_buf); lpIQ_buf = NULL; } } return 0; } /* ------------------------------------------------------------------------------------ */ int main(int argc, char **argv) { FILE *fp = NULL; char *fpname = NULL; int j; int k, K; float mv[Nrs]; unsigned int mv_pos[Nrs], mv0_pos[Nrs]; int mp[Nrs]; int header_found = 0; int herrs; float thres = 0.76; float tl = -1.0; int j_max; float mv_max; int d2_tn = Nrs; #ifdef CYGWIN _setmode(fileno(stdin), _O_BINARY); // _setmode(_fileno(stdin), _O_BINARY); #endif setbuf(stdout, NULL); fpname = argv[0]; ++argv; while ((*argv) && (!wavloaded)) { if ( (strcmp(*argv, "-h") == 0) || (strcmp(*argv, "--help") == 0) ) { fprintf(stderr, "%s [options] audio.wav\n", fpname); fprintf(stderr, " options:\n"); fprintf(stderr, " -v (verbose)\n"); fprintf(stderr, " -c (continuous)\n"); fprintf(stderr, " --iq (IF iq-data)\n"); fprintf(stderr, " --IQ (baseband IQ at fq)\n"); fprintf(stderr, " --bw (set IQ filter bw/kHz)\n"); return 0; } else if ( (strcmp(*argv, "-v") == 0) || (strcmp(*argv, "--verbose") == 0) ) { option_verbose = 1; } else if ( (strcmp(*argv, "--iq") == 0) ) { option_iq = 1; } else if (strcmp(*argv, "--IQ") == 0) { // fq baseband -> IF (rotate from and decimate) double fq = 0.0; // --IQ , -0.5 < fq < 0.5 ++argv; if (*argv) fq = atof(*argv); else return -1; if (fq < -0.5) fq = -0.5; if (fq > 0.5) fq = 0.5; dsp__xlt_fq = -fq; // S(t) -> S(t)*exp(-f*2pi*I*t) option_iq = 5; } else if (strcmp(*argv, "--bw") == 0) { // set IQ filter bandwidth / kHz double bw_kHz = 0.0; ++argv; if (*argv) bw_kHz = atof(*argv); else return -1; if (bw_kHz < 1.0) bw_kHz = 0.0; // min. 1kHz set_lpIQ = bw_kHz * 1e3; } else if ( (strcmp(*argv, "--dc") == 0) ) { option_dc = 1; } else if (strcmp(*argv, "--min") == 0) { option_min = 1; } else if ( (strcmp(*argv, "-L") == 0) ) { // L-band 1680kHz (IQ: decimation not limited) lpIQ_bw[0] = 20e3; lpIQ_bw[1] = 32e3; lpIQ_bw[2] = 200e3; lpIQ_bw[3] = 400e3; } else if ( (strcmp(*argv, "-c") == 0) || (strcmp(*argv, "--cnt") == 0) ) { option_cont = 1; } else if ( (strcmp(*argv, "-s") == 0) || (strcmp(*argv, "--silent") == 0) ) { option_silent = 1; } else if ( (strcmp(*argv, "-t") == 0) || (strcmp(*argv, "--time") == 0) ) { ++argv; if (*argv) tl = atof(*argv); else return -50; } else if ( (strcmp(*argv, "-d2") == 0) ) { option_d2 = 1; } else if ( (strcmp(*argv, "--ch2") == 0) ) { wav_channel = 1; } // right channel (default: 0=left) else if ( (strcmp(*argv, "--ths") == 0) ) { ++argv; if (*argv) { thres = atof(*argv); for (j = 0; j < Nrs; j++) rs_hdr[j].thres = thres; } else return -50; } else if (strcmp(*argv, "-") == 0) { ++argv; if (*argv) sample_rate = atoi(*argv); else return -1; ++argv; if (*argv) bits_sample = atoi(*argv); else return -1; channels = 2; if (sample_rate < 1 || (bits_sample != 8 && bits_sample != 16 && bits_sample != 32)) { fprintf(stderr, "- \n"); return -1; } option_pcmraw = 1; } else { fp = fopen(*argv, "rb"); if (fp == NULL) { fprintf(stderr, "error: open %s\n", *argv); return -50; } wavloaded = 1; } ++argv; } if (!wavloaded) fp = stdin; if (option_d2) { option_cont = 0; } if (option_pcmraw == 0) { j = read_wav_header(fp, wav_channel); if ( j < 0 ) { fclose(fp); fprintf(stderr, "error: wav header\n"); return -50; } } if (option_iq && channels < 2) { fprintf(stderr, "error: iq channels < 2\n"); return -50; } K = init_buffers(); if ( K < 0 ) { fprintf(stderr, "error: init buffers\n"); return -50; }; for (j = 0; j < Nrs; j++) { mv[j] = 0.0; mv_pos[j] = 0; mp[j] = 0; } j_max = 0; mv_max = 0.0; k = 0; while ( f32buf_sample(fp, option_inv) != EOF ) { if (tl > 0 && sample_in > (tl+1)*sample_rate) break; // (int)sample_out < 0 k += 1; if (k >= K-4) { for (j = 0; j <= idxIMETafsk; j++) { // incl. IMET-preamble if ( j == idx_MTS01 ) continue; // only ifdef NOMTS01 if ( j == idx_C34C50 ) continue; // only ifdef NOC34C50 if ( j == idx_WXR301 ) continue; // only ifdef NOWXR301 if ( j == idx_IMET1AB ) continue; // only ifdef NOIMET1AB mv0_pos[j] = mv_pos[j]; mp[j] = getCorrDFT(K, 0, mv+j, mv_pos+j, rs_hdr+j); } k = 0; } else { //for (j = 0; j < Nrs; j++) mv[j] = 0.0; continue; } header_found = 0; for (j = 0; j <= idxIMETafsk; j++) // incl. IMET-preamble { if (mp[j] > 0 && (mv[j] > rs_hdr[j].thres || mv[j] < -rs_hdr[j].thres)) { if (mv_pos[j] > mv0_pos[j]) { herrs = headcmp(1, mv_pos[j], mv[j]<0, rs_hdr+j); if (herrs < rs_hdr[j].herrs) // max bit-errors in header { if ( strncmp(rs_hdr[j].type, "M10", 3) == 0 || strncmp(rs_hdr[j].type, "M20", 3) == 0) { ui32_t bytes = frm_M10(mv_pos[j], mv[j]<0, rs_hdr+j); int len = (bytes >> 8) & 0xFF; int h = hw(bytes & 0x0F); // type byte xF or x0 ? if (h < 2 || h == 2 && (bytes&0xF0) == 0x20) { rs_hdr[j].type = "M20"; rs_hdr[j].tn = tn_M20; // M20: 45 20 } else { rs_hdr[j].type = "M10"; rs_hdr[j].tn = tn_M10; // M10: 64 9F , M10+: 64 AF , M10-dop: 64 49 (len > 0x60) } } if ( strncmp(rs_hdr[j].type, "IMETafsk", 8) == 0 ) // ? j == idxIMETafsk { int n, m; int D = N_DFT/2 - 3; float df; float pow2200, pow2400; int bin2200, bin2400; for (n = 0; n < N_DFT; n++) { xn[n] = 0.0; db[n] = 0.0; } n = 0; while (n < sample_rate) { // 1 sec if (f32buf_sample(fp, option_inv) == EOF) break;//goto ende; xn[n % D] = buf_fm[rs_hdr[j].lpIQ][sample_out % M]; n++; if (n % D == 0) { dft(xn, X); for (m = 0; m < N_DFT; m++) db[m] += cabs(X[m]); } } df = bin2freq(1); m = 50.0/df; if (m < 1) m = 1; if (freq2bin(2500) > N_DFT/2) goto ende; bin2200 = freq2bin(2200); pow2200 = 0.0; for (n = 0; n < m; n++) pow2200 += db[ bin2200 - m/4 + n ]; bin2400 = freq2bin(2400); pow2400 = 0.0; for (n = 0; n < m; n++) pow2400 += db[ bin2400 - m/4 + n ]; mv[j] = fabs(mv[j]); if (pow2200 > pow2400) { // IMET1RS: peak1: 1200Hz > peak2: 2200Hz > pow(800Hz) int bin800 = freq2bin(800); float pow800 = 0.0; for (n = 0; n < m; n++) pow800 += db[ bin800 - m/4 + n ]; if (pow2200 > pow800) { // IMET -> IMET1RS/IMET4 int _j0 = j; if (option_iq && set_lpIQ > 50e3) j = idxRS; else j = idxI4; mv[j] = mv[_j0]; mv_pos[j] = mv_pos[_j0]; rs_hdr[j].dc = rs_hdr[_j0].dc; rs_hdr[j].df = rs_hdr[_j0].df; mv[_j0] = 0.0; header_found = 1; } else mv[j] = 0.0; } else { // IMET -> IMET1AB ? // IMET1AB post-processing might block MRZ detection // skip after number of tries or detect imet1ab directly // mv[j] = 0.0; } } else { // if not IMET header_found = 1; } if (header_found) { if (!option_silent && (mv[j] > rs_hdr[j].thres || mv[j] < -rs_hdr[j].thres)) { if (option_d2) { rs_detect2[j] += 1; d2_tn = rs_d2(); if ( d2_tn == Nrs ) header_found = 0; } if ( !option_d2 || j == d2_tn ) { if (option_verbose) fprintf(stdout, "sample: %d\n", mv_pos[j]); fprintf(stdout, "%s: %.4f", rs_hdr[j].type, mv[j]); if (option_dc && option_iq) { fprintf(stdout, " , %+.1fHz", rs_hdr[j].df*sr_base); if (option_verbose) { fprintf(stdout, " [ fq-ofs: %+.6f", rs_hdr[j].df); fprintf(stdout, " = %+.1fHz ]", rs_hdr[j].df*sr_base); } } fprintf(stdout, "\n"); } } // if ((j < 3) && mv[j] < 0) header_found = -1; if ( fabs(mv_max) < fabs(mv[j]) ) { // j-weights? mv_max = mv[j]; j_max = j; } } } } } } if (header_found && !option_cont || d2_tn < Nrs) break; header_found = 0; for (j = 0; j < Nrs; j++) mv[j] = 0.0; } ende: free_buffers(); fclose(fp); // return only best result // latest: j if (mv_max) { if (mv_max < 0 && j_max < 3) header_found = -1; else header_found = 1; } else header_found = 0; return (header_found * rs_hdr[j_max].tn); }