kopia lustrzana https://github.com/rs1729/RS
1148 wiersze
29 KiB
C
1148 wiersze
29 KiB
C
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/*
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* compile:
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*
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* gcc -Ofast iq_dec.c -lm -o iq_dec
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*
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*
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* usage:
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*
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* ./iq_dec [--bo <b>] --iq <fq> [iq_baseband.wav] # <b>=8,16,32 bit output
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* ./iq_dec [--bo <b>] --iq <fq> - <sr> <bs> [iq_baseband.raw]
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*
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* ./iq_dec [--bo <b>] [--wav] [--FM] --iq <fq> iq_baseband.wav
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* ./iq_dec [--bo <b>] [--wav] [--decFM] --iq <fq> - <sr> <bs> [iq_baseband.raw]
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* --wav : output wav header
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* --FM/decFM : FM demodulation
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*
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*
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* author: zilog80
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*/
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/* ------------------------------------------------------------------------------------ */
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#define FM_GAIN (0.8)
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/* ------------------------------------------------------------------------------------ */
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#include <math.h>
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#include <complex.h>
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#ifndef M_PI
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#define M_PI (3.1415926535897932384626433832795)
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#endif
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#define _2PI (6.2831853071795864769252867665590)
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#define LP_IQ 1
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#define LP_FM 2
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#define LP_IQFM 4
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#ifndef INTTYPES
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#define INTTYPES
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typedef unsigned char ui8_t;
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typedef unsigned short ui16_t;
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typedef unsigned int ui32_t;
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typedef unsigned long long ui64_t;
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typedef char i8_t;
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typedef short i16_t;
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typedef int i32_t;
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#endif
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typedef struct {
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FILE *fp;
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//
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int sr; // sample_rate
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int bps; // bits/sample
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int nch; // channels
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int ch; // select channel
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//
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int bps_out;
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//
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ui32_t sample_in;
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ui32_t sample_out;
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//
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// IQ-data
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int opt_iq;
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int opt_iqdc;
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double V_noise;
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double V_signal;
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double SNRdB;
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// decimate
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int opt_nolut; // default: LUT
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int opt_IFmin;
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int decM;
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int decFM;
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ui32_t sr_base;
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ui32_t dectaps;
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ui32_t sample_decX;
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ui32_t lut_len;
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ui32_t sample_decM;
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float complex *decXbuffer;
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float complex *decMbuf;
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float complex *ex; // exp_lut
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double xlt_fq;
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int opt_fm;
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int opt_lp;
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// IF: lowpass
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int lpIQ_bw;
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int lpIQtaps; // ui32_t
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float lpIQ_fbw;
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float *ws_lpIQ;
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float complex *lpIQ_buf;
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// FM: lowpass
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int lpFM_bw;
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int lpFMtaps; // ui32_t
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float *ws_lpFM;
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float *lpFM_buf;
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float *fm_buffer;
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} dsp_t;
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typedef struct {
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int sr; // sample_rate
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int sr_out;
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int bps; // bits_sample bits/sample
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int bps_out;
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int nch; // channels
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int sel_ch; // select wav channel
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} pcm_t;
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/* ------------------------------------------------------------------------------------ */
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static int findstr(char *buff, char *str, int pos) {
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int i;
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for (i = 0; i < 4; i++) {
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if (buff[(pos+i)%4] != str[i]) break;
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}
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return i;
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}
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static int read_wav_header(pcm_t *pcm, FILE *fp) {
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char txt[4+1] = "\0\0\0\0";
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unsigned char dat[4];
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int byte, p=0;
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int sample_rate = 0, bits_sample = 0, channels = 0;
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if (fread(txt, 1, 4, fp) < 4) return -1;
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if (strncmp(txt, "RIFF", 4) && strncmp(txt, "RF64", 4)) return -1;
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if (fread(txt, 1, 4, fp) < 4) return -1;
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// pos_WAVE = 8L
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if (fread(txt, 1, 4, fp) < 4) return -1;
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if (strncmp(txt, "WAVE", 4)) return -1;
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// pos_fmt = 12L
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for ( ; ; ) {
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if ( (byte=fgetc(fp)) == EOF ) return -1;
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txt[p % 4] = byte;
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p++; if (p==4) p=0;
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if (findstr(txt, "fmt ", p) == 4) break;
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}
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if (fread(dat, 1, 4, fp) < 4) return -1;
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if (fread(dat, 1, 2, fp) < 2) return -1;
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if (fread(dat, 1, 2, fp) < 2) return -1;
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channels = dat[0] + (dat[1] << 8);
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if (fread(dat, 1, 4, fp) < 4) return -1;
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memcpy(&sample_rate, dat, 4); //sample_rate = dat[0]|(dat[1]<<8)|(dat[2]<<16)|(dat[3]<<24);
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if (fread(dat, 1, 4, fp) < 4) return -1;
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if (fread(dat, 1, 2, fp) < 2) return -1;
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//byte = dat[0] + (dat[1] << 8);
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if (fread(dat, 1, 2, fp) < 2) return -1;
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bits_sample = dat[0] + (dat[1] << 8);
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// pos_dat = 36L + info
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for ( ; ; ) {
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if ( (byte=fgetc(fp)) == EOF ) return -1;
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txt[p % 4] = byte;
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p++; if (p==4) p=0;
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if (findstr(txt, "data", p) == 4) break;
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}
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if (fread(dat, 1, 4, fp) < 4) return -1;
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fprintf(stderr, "sample_rate: %d\n", sample_rate);
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fprintf(stderr, "bits : %d\n", bits_sample);
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fprintf(stderr, "channels : %d\n", channels);
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if (pcm->sel_ch < 0 || pcm->sel_ch >= channels) pcm->sel_ch = 0; // default channel: 0
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if (bits_sample != 8 && bits_sample != 16 && bits_sample != 32) return -1;
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if (sample_rate == 900001) sample_rate -= 1;
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pcm->sr = sample_rate;
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pcm->bps = bits_sample;
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pcm->nch = channels;
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return 0;
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}
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static float write_wav_header(pcm_t *pcm) {
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FILE *fp = stdout;
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ui32_t sr = pcm->sr_out;
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ui32_t bps = pcm->bps_out;
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ui32_t data = 0;
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fwrite("RIFF", 1, 4, fp);
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data = 0; // bytes-8=headersize-8+datasize
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fwrite(&data, 1, 4, fp);
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fwrite("WAVE", 1, 4, fp);
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fwrite("fmt ", 1, 4, fp);
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data = 16; if (bps == 32) data += 2;
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fwrite(&data, 1, 4, fp);
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if (bps == 32) data = 3; // IEEE float
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else data = 1; // PCM
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fwrite(&data, 1, 2, fp);
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data = pcm->nch; // channels
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fwrite(&data, 1, 2, fp);
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data = sr;
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fwrite(&data, 1, 4, fp);
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data = sr*bps/8;
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fwrite(&data, 1, 4, fp);
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data = (bps+7)/8;
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fwrite(&data, 1, 2, fp);
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data = bps;
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fwrite(&data, 1, 2, fp);
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if (bps == 32) {
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data = 0; // size of extension: 0
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fwrite(&data, 1, 2, fp);
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}
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fwrite("data", 1, 4, fp);
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data = 0xFFFFFFFF; // datasize unknown
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fwrite(&data, 1, 4, fp);
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return 0;
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}
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static int f32read_sample(dsp_t *dsp, float *s) {
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int i;
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unsigned int word = 0;
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short *b = (short*)&word;
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float *f = (float*)&word;
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for (i = 0; i < dsp->nch; i++) {
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if (fread( &word, dsp->bps/8, 1, dsp->fp) != 1) return EOF;
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if (i == dsp->ch) { // i = 0: links bzw. mono
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//if (bits_sample == 8) sint = b-128; // 8bit: 00..FF, centerpoint 0x80=128
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//if (bits_sample == 16) sint = (short)b;
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if (dsp->bps == 32) {
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*s = *f;
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}
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else {
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if (dsp->bps == 8) { *b -= 128; }
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*s = *b/128.0;
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if (dsp->bps == 16) { *s /= 256.0; }
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}
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}
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}
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return 0;
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}
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typedef struct {
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double sumIQx;
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double sumIQy;
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float avgIQx;
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float avgIQy;
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float complex avgIQ;
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ui32_t cnt;
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ui32_t maxcnt;
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ui32_t maxlim;
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} iq_dc_t;
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static iq_dc_t IQdc;
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static int f32read_csample(dsp_t *dsp, float complex *z) {
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float x, y;
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if (dsp->bps == 32) { //float32
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float f[2];
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if (fread( f, dsp->bps/8, 2, dsp->fp) != 2) return EOF;
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x = f[0];
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y = f[1];
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}
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else if (dsp->bps == 16) { //int16
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short b[2];
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if (fread( b, dsp->bps/8, 2, dsp->fp) != 2) return EOF;
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x = b[0]/32768.0;
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y = b[1]/32768.0;
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}
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else { // dsp->bps == 8 //uint8
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ui8_t u[2];
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if (fread( u, dsp->bps/8, 2, dsp->fp) != 2) return EOF;
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x = (u[0]-128)/128.0;
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y = (u[1]-128)/128.0;
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}
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*z = x + I*y;
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// IQ-dc removal optional
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if (dsp->opt_iqdc) {
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*z -= IQdc.avgIQ;
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IQdc.sumIQx += x;
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IQdc.sumIQy += y;
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IQdc.cnt += 1;
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if (IQdc.cnt == IQdc.maxcnt) {
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IQdc.avgIQx = IQdc.sumIQx/(float)IQdc.maxcnt;
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IQdc.avgIQy = IQdc.sumIQy/(float)IQdc.maxcnt;
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IQdc.avgIQ = IQdc.avgIQx + I*IQdc.avgIQy;
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IQdc.sumIQx = 0; IQdc.sumIQy = 0; IQdc.cnt = 0;
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if (IQdc.maxcnt < IQdc.maxlim) IQdc.maxcnt *= 2;
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}
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}
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return 0;
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}
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static int f32read_cblock(dsp_t *dsp) {
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int n;
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int len;
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float x, y;
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ui8_t s[4*2*dsp->decM]; //uin8,int16,float32
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ui8_t *u = (ui8_t*)s;
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short *b = (short*)s;
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float *f = (float*)s;
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len = fread( s, dsp->bps/8, 2*dsp->decM, dsp->fp) / 2;
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//for (n = 0; n < len; n++) dsp->decMbuf[n] = (u[2*n]-128)/128.0 + I*(u[2*n+1]-128)/128.0;
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// u8: 0..255, 128 -> 0V
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for (n = 0; n < len; n++) {
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if (dsp->bps == 8) { //uint8
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x = (u[2*n ]-128)/128.0;
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y = (u[2*n+1]-128)/128.0;
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}
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else if (dsp->bps == 16) { //int16
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x = b[2*n ]/32768.0;
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y = b[2*n+1]/32768.0;
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}
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else { // dsp->bps == 32 //float32
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x = f[2*n];
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y = f[2*n+1];
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}
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// baseband: IQ-dc removal mandatory
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dsp->decMbuf[n] = (x-IQdc.avgIQx) + I*(y-IQdc.avgIQy);
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IQdc.sumIQx += x;
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IQdc.sumIQy += y;
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IQdc.cnt += 1;
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if (IQdc.cnt == IQdc.maxcnt) {
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IQdc.avgIQx = IQdc.sumIQx/(float)IQdc.maxcnt;
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IQdc.avgIQy = IQdc.sumIQy/(float)IQdc.maxcnt;
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IQdc.avgIQ = IQdc.avgIQx + I*IQdc.avgIQy;
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IQdc.sumIQx = 0; IQdc.sumIQy = 0; IQdc.cnt = 0;
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if (IQdc.maxcnt < IQdc.maxlim) IQdc.maxcnt *= 2;
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}
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}
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return len;
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}
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// decimate lowpass
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static float *ws_dec;
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static double sinc(double x) {
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double y;
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if (x == 0) y = 1;
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else y = sin(M_PI*x)/(M_PI*x);
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return y;
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}
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static int lowpass_init(float f, int taps, float **pws) {
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double *h, *w;
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double norm = 0;
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int n;
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float *ws = NULL;
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if (taps % 2 == 0) taps++; // odd/symmetric
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if ( taps < 1 ) taps = 1;
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h = (double*)calloc( taps+1, sizeof(double)); if (h == NULL) return -1;
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w = (double*)calloc( taps+1, sizeof(double)); if (w == NULL) return -1;
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ws = (float*)calloc( 2*taps+1, sizeof(float)); if (ws == NULL) return -1;
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for (n = 0; n < taps; n++) {
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w[n] = 7938/18608.0 - 9240/18608.0*cos(_2PI*n/(taps-1)) + 1430/18608.0*cos(4*M_PI*n/(taps-1)); // Blackmann
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h[n] = 2*f*sinc(2*f*(n-(taps-1)/2));
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ws[n] = w[n]*h[n];
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norm += ws[n]; // 1-norm
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}
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for (n = 0; n < taps; n++) {
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ws[n] /= norm; // 1-norm
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}
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for (n = 0; n < taps; n++) ws[taps+n] = ws[n]; // duplicate/unwrap
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*pws = ws;
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free(h); h = NULL;
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free(w); w = NULL;
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return taps;
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}
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static int lowpass_update(float f, int taps, float *ws) {
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double *h, *w;
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double norm = 0;
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int n;
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if (taps % 2 == 0) taps++; // odd/symmetric
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if ( taps < 1 ) taps = 1;
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h = (double*)calloc( taps+1, sizeof(double)); if (h == NULL) return -1;
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w = (double*)calloc( taps+1, sizeof(double)); if (w == NULL) return -1;
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for (n = 0; n < taps; n++) {
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w[n] = 7938/18608.0 - 9240/18608.0*cos(_2PI*n/(taps-1)) + 1430/18608.0*cos(4*M_PI*n/(taps-1)); // Blackmann
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h[n] = 2*f*sinc(2*f*(n-(taps-1)/2));
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ws[n] = w[n]*h[n];
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norm += ws[n]; // 1-norm
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}
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for (n = 0; n < taps; n++) {
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ws[n] /= norm; // 1-norm
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}
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for (n = 0; n < taps; n++) ws[taps+n] = ws[n];
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free(h); h = NULL;
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free(w); w = NULL;
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return taps;
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}
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static float complex lowpass0(float complex buffer[], ui32_t sample, ui32_t taps, float *ws) {
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ui32_t n;
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double complex w = 0;
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for (n = 0; n < taps; n++) {
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w += buffer[(sample+n)%taps]*ws[taps-1-n];
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}
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return (float complex)w;
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}
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//static __attribute__((optimize("-ffast-math"))) float complex lowpass()
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static float complex lowpass(float complex buffer[], ui32_t sample, ui32_t taps, float *ws) {
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float complex w = 0;
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int n; // -Ofast
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int S = taps - (sample % taps);
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for (n = 0; n < taps; n++) {
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w += buffer[n]*ws[S+n]; // ws[taps+s-n] = ws[(taps+sample-n)%taps]
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}
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return w;
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// symmetry: ws[n] == ws[taps-1-n]
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}
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static float complex lowpass2(float complex buffer[], ui32_t sample, ui32_t taps, float *ws) {
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float complex w = 0;
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int n;
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int s = sample % taps;
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int S1 = s;
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int S1N = S1-taps;
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int n0 = taps-s;
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for (n = 0; n < n0; n++) {
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w += buffer[S1+n]*ws[n];
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}
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for (n = n0; n < taps; n++) {
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w += buffer[S1N+n]*ws[n];
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}
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return w;
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// symmetry: ws[n] == ws[taps-1-n]
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}
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static float re_lowpass0(float buffer[], ui32_t sample, ui32_t taps, float *ws) {
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ui32_t n;
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double w = 0;
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for (n = 0; n < taps; n++) {
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w += buffer[(sample+n)%taps]*ws[taps-1-n];
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}
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return (float)w;
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}
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static float re_lowpass(float buffer[], ui32_t sample, ui32_t taps, float *ws) {
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float w = 0;
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int n;
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int S = taps - (sample % taps);
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for (n = 0; n < taps; n++) {
|
|
w += buffer[n]*ws[S+n]; // ws[taps+s-n] = ws[(taps+sample-n)%taps]
|
|
}
|
|
return w;
|
|
}
|
|
|
|
|
|
static int ifblock(dsp_t *dsp, float complex *z_out) {
|
|
|
|
float complex z;
|
|
int j;
|
|
|
|
if ( f32read_cblock(dsp) < dsp->decM ) return EOF;
|
|
|
|
for (j = 0; j < dsp->decM; j++) {
|
|
if (dsp->opt_nolut) {
|
|
double _s_base = (double)(dsp->sample_in*dsp->decM+j); // dsp->sample_dec
|
|
double f0 = dsp->xlt_fq*_s_base;
|
|
z = dsp->decMbuf[j] * cexp(f0*_2PI*I);
|
|
}
|
|
else {
|
|
z = dsp->decMbuf[j] * dsp->ex[dsp->sample_decM];
|
|
}
|
|
dsp->sample_decM += 1; if (dsp->sample_decM >= dsp->lut_len) dsp->sample_decM = 0;
|
|
|
|
dsp->decXbuffer[dsp->sample_decX] = z;
|
|
dsp->sample_decX += 1; if (dsp->sample_decX >= dsp->dectaps) dsp->sample_decX = 0;
|
|
}
|
|
if (dsp->decM > 1)
|
|
{
|
|
z = lowpass(dsp->decXbuffer, dsp->sample_decX, dsp->dectaps, ws_dec);
|
|
}
|
|
|
|
*z_out = z;
|
|
|
|
dsp->sample_in += 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int if_fm(dsp_t *dsp, float complex *z_out, float *s) {
|
|
|
|
static float complex z0;
|
|
float complex z, w;
|
|
float s_fm = 0.0f;
|
|
float gain = FM_GAIN;
|
|
ui32_t _sample = dsp->sample_in * dsp->decFM;
|
|
int m;
|
|
int j;
|
|
|
|
for (m = 0; m < dsp->decFM; m++)
|
|
{
|
|
|
|
if ( f32read_cblock(dsp) < dsp->decM ) return EOF;
|
|
|
|
for (j = 0; j < dsp->decM; j++) {
|
|
if (dsp->opt_nolut) {
|
|
double _s_base = (double)(_sample*dsp->decM+j); // dsp->sample_dec
|
|
double f0 = dsp->xlt_fq*_s_base;
|
|
z = dsp->decMbuf[j] * cexp(f0*_2PI*I);
|
|
}
|
|
else {
|
|
z = dsp->decMbuf[j] * dsp->ex[dsp->sample_decM];
|
|
}
|
|
dsp->sample_decM += 1; if (dsp->sample_decM >= dsp->lut_len) dsp->sample_decM = 0;
|
|
|
|
dsp->decXbuffer[dsp->sample_decX] = z;
|
|
dsp->sample_decX += 1; if (dsp->sample_decX >= dsp->dectaps) dsp->sample_decX = 0;
|
|
}
|
|
if (dsp->decM > 1)
|
|
{
|
|
z = lowpass(dsp->decXbuffer, dsp->sample_decX, dsp->dectaps, ws_dec);
|
|
}
|
|
|
|
// IF-lowpass
|
|
if (dsp->opt_lp & LP_IQ) {
|
|
dsp->lpIQ_buf[_sample % dsp->lpIQtaps] = z;
|
|
z = lowpass(dsp->lpIQ_buf, _sample+1, dsp->lpIQtaps, dsp->ws_lpIQ);
|
|
}
|
|
|
|
if (dsp->opt_fm) {
|
|
w = z * conj(z0);
|
|
s_fm = gain * carg(w)/M_PI;
|
|
z0 = z;
|
|
|
|
// FM-lowpass
|
|
if (dsp->opt_lp & LP_FM) {
|
|
dsp->lpFM_buf[_sample % dsp->lpFMtaps] = s_fm;
|
|
if (m+1 == dsp->decFM) {
|
|
s_fm = re_lowpass(dsp->lpFM_buf, _sample+1, dsp->lpFMtaps, dsp->ws_lpFM);
|
|
}
|
|
}
|
|
}
|
|
|
|
*z_out = z;
|
|
|
|
_sample += 1;
|
|
|
|
}
|
|
|
|
*s = s_fm;
|
|
|
|
dsp->sample_in += 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* -------------------------------------------------------------------------- */
|
|
|
|
#define IF_SAMPLE_RATE 48000
|
|
#define IF_SAMPLE_RATE_MIN 32000
|
|
|
|
static int IF_min = IF_SAMPLE_RATE;
|
|
|
|
#define IF_TRANSITION_BW (4e3) // 4kHz transition width
|
|
#define FM_TRANSITION_BW (2e3) // 2kHz transition width
|
|
|
|
|
|
static int init_buffers(dsp_t *dsp) {
|
|
|
|
int K = 0;
|
|
int n, k;
|
|
|
|
|
|
// decimate
|
|
int IF_sr = IF_min; // designated IF sample rate
|
|
int decM = 1; // decimate M:1
|
|
int sr_base = dsp->sr;
|
|
float f_lp; // dec_lowpass: lowpass_bandwidth/2
|
|
float t_bw; // dec_lowpass: transition_bandwidth
|
|
int taps; // dec_lowpass: taps
|
|
|
|
//if (dsp->opt_IFmin) 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); // for IF=48k
|
|
t_bw = (IF_sr-20e3)/*/2.0*/;
|
|
if (dsp->opt_IFmin) {
|
|
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); // decimate lowpass
|
|
if (taps < 0) return -1;
|
|
dsp->dectaps = (ui32_t)taps;
|
|
|
|
dsp->sr_base = sr_base;
|
|
dsp->sr = IF_sr; // sr_base/decM
|
|
dsp->decM = decM;
|
|
|
|
fprintf(stderr, "IF: %d\n", IF_sr);
|
|
fprintf(stderr, "dec: %d\n", decM);
|
|
|
|
|
|
if (!dsp->opt_nolut)
|
|
{
|
|
// 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++) {
|
|
double t = f0*(double)n;
|
|
dsp->ex[n] = cexp(t*_2PI*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 lowpass
|
|
if (dsp->opt_lp & LP_IQ)
|
|
{
|
|
float f_lp; // lowpass_bw
|
|
int taps; // lowpass taps: 4*sr/transition_bw
|
|
|
|
f_lp = 24e3/(float)dsp->sr/2.0; // default
|
|
if (dsp->lpIQ_bw) f_lp = dsp->lpIQ_bw/(float)dsp->sr/2.0;
|
|
taps = 4*dsp->sr/IF_TRANSITION_BW; if (taps%2==0) taps++;
|
|
taps = lowpass_init(f_lp, taps, &dsp->ws_lpIQ); if (taps < 0) return -1;
|
|
|
|
dsp->lpIQ_fbw = f_lp;
|
|
dsp->lpIQtaps = taps;
|
|
dsp->lpIQ_buf = calloc( dsp->lpIQtaps+3, sizeof(float complex));
|
|
if (dsp->lpIQ_buf == NULL) return -1;
|
|
|
|
}
|
|
|
|
// FM lowpass
|
|
if (dsp->opt_lp & LP_FM)
|
|
{
|
|
float f_lp; // lowpass_bw
|
|
int taps; // lowpass taps: 4*sr/transition_bw
|
|
|
|
f_lp = 10e3/(float)dsp->sr; // default
|
|
if (dsp->lpFM_bw > 0) f_lp = dsp->lpFM_bw/(float)dsp->sr;
|
|
taps = 4*dsp->sr/FM_TRANSITION_BW; if (taps%2==0) taps++;
|
|
taps = lowpass_init(f_lp, taps, &dsp->ws_lpFM); if (taps < 0) return -1;
|
|
|
|
dsp->lpFMtaps = taps;
|
|
dsp->lpFM_buf = calloc( dsp->lpFMtaps+3, sizeof(float complex));
|
|
if (dsp->lpFM_buf == NULL) return -1;
|
|
}
|
|
|
|
|
|
memset(&IQdc, 0, sizeof(IQdc));
|
|
IQdc.maxlim = dsp->sr;
|
|
IQdc.maxcnt = IQdc.maxlim/32; // 32,16,8,4,2,1
|
|
if (dsp->decM > 1) {
|
|
IQdc.maxlim *= dsp->decM;
|
|
IQdc.maxcnt *= dsp->decM;
|
|
}
|
|
|
|
|
|
if (dsp->nch < 2) return -1;
|
|
|
|
return K;
|
|
}
|
|
|
|
static int free_buffers(dsp_t *dsp) {
|
|
|
|
// decimate
|
|
if (dsp->decXbuffer) { free(dsp->decXbuffer); dsp->decXbuffer = NULL; }
|
|
if (dsp->decMbuf) { free(dsp->decMbuf); dsp->decMbuf = NULL; }
|
|
if (!dsp->opt_nolut) {
|
|
if (dsp->ex) { free(dsp->ex); dsp->ex = NULL; }
|
|
}
|
|
|
|
if (ws_dec) { free(ws_dec); ws_dec = NULL; }
|
|
|
|
|
|
// IF lowpass
|
|
if (dsp->opt_lp & LP_IQ)
|
|
{
|
|
if (dsp->ws_lpIQ) { free(dsp->ws_lpIQ); dsp->ws_lpIQ = NULL; }
|
|
if (dsp->lpIQ_buf) { free(dsp->lpIQ_buf); dsp->lpIQ_buf = NULL; }
|
|
}
|
|
// FM lowpass
|
|
if (dsp->opt_lp & LP_FM)
|
|
{
|
|
if (dsp->ws_lpFM) { free(dsp->ws_lpFM); dsp->ws_lpFM = NULL; }
|
|
if (dsp->lpFM_buf) { free(dsp->lpFM_buf); dsp->lpFM_buf = NULL; }
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* ------------------------------------------------------------------------------------ */
|
|
|
|
#include <unistd.h>
|
|
|
|
static int write_cpx_blk(dsp_t *dsp, float complex *z, int len) {
|
|
int j, l;
|
|
short b[2*len];
|
|
ui8_t u[2*len];
|
|
float xy[2*len];
|
|
int bps = dsp->bps_out;
|
|
int fd = 1; // STDOUT_FILENO
|
|
|
|
for (j = 0; j < len; j++) {
|
|
xy[2*j ] = creal(z[j]);
|
|
xy[2*j+1] = cimag(z[j]);
|
|
}
|
|
|
|
if (bps == 32) {
|
|
l = write(fd, xy, 2*len*bps/8);
|
|
}
|
|
else {
|
|
for (j = 0; j < 2*len; j++) xy[j] *= 128.0; // 127.0
|
|
if (bps == 8) {
|
|
for (j = 0; j < 2*len; j++) {
|
|
xy[j] += 128.0; // x *= scale8b;
|
|
u[j] = (ui8_t)(xy[j]); //b = (int)(x+0.5);
|
|
}
|
|
l = write(fd, u, 2*len*bps/8);
|
|
}
|
|
else { // bps == 16
|
|
for (j = 0; j < 2*len; j++) {
|
|
xy[j] *= 256.0;
|
|
b[j] = (short)xy[j]; //b = (int)(x+0.5);
|
|
}
|
|
l = write(fd, b, 2*len*bps/8);
|
|
}
|
|
}
|
|
|
|
return l*8/(2*bps);
|
|
}
|
|
|
|
// fwrite return items: size_t fwrite(const void *ptr, size_t size, size_t nmemb, FILE *stream);
|
|
static int fwrite_cpx_blk(dsp_t *dsp, float complex *z, int len) {
|
|
int j, l;
|
|
short b[2*len];
|
|
ui8_t u[2*len];
|
|
float xy[2*len];
|
|
int bps = dsp->bps_out;
|
|
FILE *fo = stdout;
|
|
|
|
for (j = 0; j < len; j++) {
|
|
xy[2*j ] = creal(z[j]);
|
|
xy[2*j+1] = cimag(z[j]);
|
|
}
|
|
|
|
if (bps == 32) {
|
|
l = fwrite(xy, 2*bps/8, len, fo);
|
|
}
|
|
else {
|
|
for (j = 0; j < 2*len; j++) xy[j] *= 128.0; // 127.0
|
|
if (bps == 8) {
|
|
for (j = 0; j < 2*len; j++) {
|
|
xy[j] += 128.0; // x *= scale8b;
|
|
u[j] = (ui8_t)(xy[j]); //b = (int)(x+0.5);
|
|
}
|
|
l = fwrite(u, 2*bps/8, len, fo);
|
|
}
|
|
else { // bps == 16
|
|
for (j = 0; j < 2*len; j++) {
|
|
xy[j] *= 256.0;
|
|
b[j] = (short)xy[j]; //b = (int)(x+0.5);
|
|
}
|
|
l = fwrite(b, 2*bps/8, len, fo);
|
|
}
|
|
}
|
|
|
|
return l;
|
|
}
|
|
|
|
static int fwrite_fm(dsp_t *dsp, float s) {
|
|
int bps = dsp->bps_out;
|
|
FILE *fpo = stdout;
|
|
ui8_t u = 0;
|
|
i16_t b = 0;
|
|
ui32_t *w = (ui32_t*)&s;
|
|
|
|
if (bps == 8) {
|
|
s *= 127.0;
|
|
s += 128.0;
|
|
u = (ui8_t)s;
|
|
w = (ui32_t*)&u;
|
|
}
|
|
else if (bps == 16) {
|
|
s *= 127.0*256.0;
|
|
b = (i16_t)s;
|
|
w = (ui32_t*)&b;
|
|
}
|
|
fwrite( w, bps/8, 1, fpo);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int fwrite_fm_blk(dsp_t *dsp, float *s, int len) {
|
|
int j, l;
|
|
short b[len];
|
|
ui8_t u[len];
|
|
float x[len];
|
|
int bps = dsp->bps_out;
|
|
FILE *fo = stdout;
|
|
|
|
for (j = 0; j < len; j++) {
|
|
x[j] = s[j];
|
|
}
|
|
|
|
if (bps == 32) {
|
|
l = fwrite(x, bps/8, len, fo);
|
|
}
|
|
else {
|
|
for (j = 0; j < len; j++) x[j] *= 128.0; // 127.0
|
|
if (bps == 8) {
|
|
for (j = 0; j < len; j++) {
|
|
x[j] += 128.0; // x *= scale8b;
|
|
u[j] = (ui8_t)(x[j]); //b = (int)(x+0.5);
|
|
}
|
|
l = fwrite(u, bps/8, len, fo);
|
|
}
|
|
else { // bps == 16
|
|
for (j = 0; j < len; j++) {
|
|
x[j] *= 256.0;
|
|
b[j] = (short)x[j]; //b = (int)(x+0.5);
|
|
}
|
|
l = fwrite(b, bps/8, len, fo);
|
|
}
|
|
}
|
|
|
|
return l;
|
|
}
|
|
|
|
|
|
/* ------------------------------------------------------------------------------------ */
|
|
|
|
|
|
#define ZLEN 64
|
|
|
|
int main(int argc, char *argv[]) {
|
|
|
|
//int option_inv = 0; // invertiert Signal
|
|
int option_min = 0;
|
|
int option_iq = 0;
|
|
int option_iqdc = 0;
|
|
int option_lp = 0;
|
|
int option_dc = 0;
|
|
int option_noLUT = 0;
|
|
int option_pcmraw = 0;
|
|
int option_wav = 0;
|
|
int option_fm = 0;
|
|
int option_decFM = 0;
|
|
|
|
int wavloaded = 0;
|
|
|
|
FILE *fp;
|
|
char *fpname = NULL;
|
|
|
|
int k;
|
|
|
|
int bitQ;
|
|
|
|
int bps_out = 32;
|
|
float lpIQ_bw = 10e3;
|
|
|
|
|
|
pcm_t pcm = {0};
|
|
dsp_t dsp = {0}; //memset(&dsp, 0, sizeof(dsp));
|
|
|
|
|
|
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, " --iq0,2,3 (IQ data)\n");
|
|
return 0;
|
|
}
|
|
else if (strcmp(*argv, "--iqdc") == 0) { option_iqdc = 1; } // iq-dc removal (iq0,2,3)
|
|
else if (strcmp(*argv, "--iq") == 0) { // fq baseband -> IF (rotate from and decimate)
|
|
double fq = 0.0; // --iq <fq> , -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, "--IFbw") == 0) { // min IF bandwidth / kHz
|
|
int ifbw = 0;
|
|
++argv;
|
|
if (*argv) ifbw = atoi(*argv);
|
|
else return -1;
|
|
if (ifbw*1000 >= IF_SAMPLE_RATE_MIN) IF_min = ifbw*1000;
|
|
// ?option_lp |= LP_IQ;
|
|
}
|
|
else if (strcmp(*argv, "--lpIQ") == 0) { option_lp |= LP_IQ; } // IQ/IF lowpass
|
|
else if (strcmp(*argv, "--lpbw") == 0) { // IQ lowpass BW / kHz
|
|
double bw = 0.0;
|
|
++argv;
|
|
if (*argv) bw = atof(*argv);
|
|
else return -1;
|
|
if (bw > 1.0f) lpIQ_bw = bw*1e3;
|
|
option_lp |= LP_IQ;
|
|
}
|
|
else if (strcmp(*argv, "--FM") == 0) { option_fm = 1; }
|
|
else if (strcmp(*argv, "--lpFM") == 0) {
|
|
option_lp |= LP_FM; // FM lowpass
|
|
option_fm = 1;
|
|
}
|
|
else if (strcmp(*argv, "--decFM") == 0) { // FM decimation
|
|
option_decFM = 4;
|
|
option_lp |= LP_FM; // FM lowpass
|
|
option_fm = 1;
|
|
}
|
|
else if (strcmp(*argv, "--dc") == 0) { option_dc = 1; }
|
|
else if (strcmp(*argv, "--noLUT") == 0) { option_noLUT = 1; }
|
|
else if (strcmp(*argv, "--min") == 0) {
|
|
option_min = 1;
|
|
}
|
|
else if (strcmp(*argv, "--wav") == 0) {
|
|
option_wav = 1;
|
|
}
|
|
else if (strcmp(*argv, "-") == 0) {
|
|
int sample_rate = 0, bits_sample = 0, channels = 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, "- <sr> <bs>\n");
|
|
return -1;
|
|
}
|
|
pcm.sr = sample_rate;
|
|
pcm.bps = bits_sample;
|
|
pcm.nch = channels;
|
|
option_pcmraw = 1;
|
|
}
|
|
else if (strcmp(*argv, "--bo") == 0) {
|
|
++argv;
|
|
if (*argv) bps_out = atoi(*argv); else return -1;
|
|
if ((bps_out != 8 && bps_out != 16 && bps_out != 32)) {
|
|
bps_out = 0;
|
|
}
|
|
}
|
|
else {
|
|
fp = fopen(*argv, "rb");
|
|
if (fp == NULL) {
|
|
fprintf(stderr, "error: open %s\n", *argv);
|
|
return -1;
|
|
}
|
|
wavloaded = 1;
|
|
}
|
|
++argv;
|
|
}
|
|
if (!wavloaded) fp = stdin;
|
|
|
|
if (option_iq == 5 && option_dc) option_lp |= LP_FM;
|
|
|
|
// LUT faster for decM, however frequency correction after decimation
|
|
// LUT recommonded if decM > 2
|
|
//
|
|
if (option_noLUT && option_iq == 5) dsp.opt_nolut = 1; else dsp.opt_nolut = 0;
|
|
|
|
|
|
pcm.sel_ch = 0;
|
|
if (option_pcmraw == 0) {
|
|
k = read_wav_header(&pcm, fp);
|
|
if ( k < 0 ) {
|
|
fclose(fp);
|
|
fprintf(stderr, "error: wav header\n");
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
|
|
// init dsp
|
|
//
|
|
dsp.fp = fp;
|
|
dsp.sr = pcm.sr;
|
|
dsp.bps = pcm.bps;
|
|
dsp.nch = pcm.nch;
|
|
dsp.ch = pcm.sel_ch;
|
|
dsp.opt_iq = option_iq;
|
|
dsp.opt_iqdc = option_iqdc;
|
|
dsp.opt_lp = option_lp;
|
|
dsp.lpIQ_bw = lpIQ_bw; // 10e3 // IF lowpass bandwidth
|
|
dsp.lpFM_bw = 6e3; // FM audio lowpass
|
|
dsp.opt_IFmin = option_min;
|
|
dsp.bps_out = bps_out;
|
|
|
|
if (option_fm) dsp.opt_fm = 1;
|
|
|
|
k = init_buffers(&dsp);
|
|
if ( k < 0 ) {
|
|
fprintf(stderr, "error: init buffers\n");
|
|
return -1;
|
|
}
|
|
// base: dsp.sr_base
|
|
// if : dsp.sr
|
|
|
|
dsp.decFM = 1;
|
|
if (option_decFM) {
|
|
int fm_sr = dsp.sr;
|
|
while (fm_sr % 2 == 0 && fm_sr/2 >= 48000) {
|
|
fm_sr /= 2;
|
|
dsp.decFM *= 2;
|
|
}
|
|
// if (dsp.decFM > 1) option_lp |= LP_FM; // set above
|
|
dsp.opt_fm = 1;
|
|
}
|
|
|
|
pcm.sr_out = dsp.sr;
|
|
pcm.bps_out = dsp.bps_out;
|
|
if (option_fm) {
|
|
pcm.nch = 1;
|
|
pcm.sr_out = dsp.sr / dsp.decFM;
|
|
}
|
|
if (option_wav) write_wav_header( &pcm );
|
|
|
|
|
|
int len = ZLEN;
|
|
int l, n = 0;
|
|
|
|
float complex z_vec[ZLEN]; // init ?
|
|
float s_vec[ZLEN];
|
|
|
|
bitQ = 0;
|
|
while ( bitQ != EOF )
|
|
{
|
|
bitQ = if_fm(&dsp, z_vec+n, s_vec+n);
|
|
n++;
|
|
if (n == len || bitQ == EOF) {
|
|
if (bitQ == EOF) n--;
|
|
if (dsp.opt_fm) {
|
|
l = fwrite_fm_blk(&dsp, s_vec, n);
|
|
}
|
|
else {
|
|
l = fwrite_cpx_blk(&dsp, z_vec, n);
|
|
}
|
|
n = 0;
|
|
}
|
|
}
|
|
|
|
|
|
free_buffers(&dsp);
|
|
|
|
fclose(fp);
|
|
|
|
return 0;
|
|
}
|
|
|