Merged teejez -> feature/digitalmods

Author: ha7ilm

csdr.c

@@ -3170,6 +3170,141 @@ int main(int argc, char *argv[])
         return 0;
     }
 
+    if(!strcmp(argv[1],"shift_addition_fc"))
+    {
+        bigbufs=1;
+
+        float starting_phase=0;
+        float rate;
+
+        int fd;
+        if(fd=init_fifo(argc,argv))
+        {
+            while(!read_fifo_ctl(fd,"%g\n",&rate)) usleep(10000);
+        }
+        else
+        {
+            if(argc<=2) return badsyntax("need required parameter (rate)");
+            sscanf(argv[2],"%g",&rate);
+        }
+
+        if(!sendbufsize(initialize_buffers())) return -2;
+        for(;;)
+        {
+            shift_addition_data_t data=shift_addition_init(rate);
+            fprintf(stderr,"shift_addition_fc: reinitialized to %g\n",rate);
+            int remain, current_size;
+            float* ibufptr;
+            float* obufptr;
+            for(;;)
+            {
+                FEOF_CHECK;
+                if(!FREAD_R) break;
+                remain=the_bufsize;
+                ibufptr=input_buffer;
+                obufptr=output_buffer;
+                while(remain)
+                {
+                    current_size=(remain>1024)?1024:remain;
+                    starting_phase=shift_addition_fc(ibufptr, (complexf*)obufptr, current_size, data, starting_phase);
+                    ibufptr+=current_size;
+                    obufptr+=current_size*2;
+                    remain-=current_size;
+                }
+                FWRITE_C;
+                if(read_fifo_ctl(fd,"%g\n",&rate)) break;
+                TRY_YIELD;
+            }
+        }
+        return 0;
+    }
+
+    if(!strcmp(argv[1],"fft_fc"))
+    {
+        /*
+        For real FFT, the parameter is the number of output complex bins
+        instead of the actual FFT size.
+        Number of input samples used for each FFT is twice the given parameter.
+        This makes it easier to replace fft_cc by fft_fc in some applications. */
+        if(argc<=3) return badsyntax("need required parameters (fft_out_size, out_of_every_n_samples)");
+        int fft_in_size=0, fft_out_size=0;
+        sscanf(argv[2],"%d",&fft_out_size);
+        if(log2n(fft_out_size)==-1) return badsyntax("fft_out_size should be power of 2");
+        fft_in_size = 2*fft_out_size;
+        int every_n_samples;
+        sscanf(argv[3],"%d",&every_n_samples);
+        int benchmark=0;
+        int octave=0;
+        window_t window = WINDOW_DEFAULT;
+        if(argc>=5)
+        {
+            window=firdes_get_window_from_string(argv[4]);
+        }
+        if(argc>=6)
+        {
+            benchmark|=!strcmp("--benchmark",argv[5]);
+            octave|=!strcmp("--octave",argv[5]);
+        }
+        if(argc>=7)
+        {
+            benchmark|=!strcmp("--benchmark",argv[6]);
+            octave|=!strcmp("--octave",argv[6]);
+        }
+
+        if(!initialize_buffers()) return -2;
+        sendbufsize(fft_out_size);
+
+        //make FFT plan
+        float* input=(float*)fft_malloc(sizeof(float)*fft_in_size);
+        float* windowed=(float*)fft_malloc(sizeof(float)*fft_in_size);
+        complexf* output=(complexf*)fft_malloc(sizeof(complexf)*fft_out_size);
+        if(benchmark) fprintf(stderr,"fft_cc: benchmarking...");
+        FFT_PLAN_T* plan=make_fft_r2c(fft_in_size, windowed, output, benchmark);
+        if(benchmark) fprintf(stderr," done\n");
+        //if(octave) printf("setenv(\"GNUTERM\",\"X11 noraise\");y=zeros(1,%d);semilogy(y,\"ydatasource\",\"y\");\n",fft_size); // TODO
+        float *windowt;
+        windowt = precalculate_window(fft_in_size, window);
+        for(;;)
+        {
+            FEOF_CHECK;
+            if(every_n_samples>fft_in_size)
+            {
+                fread(input, sizeof(float), fft_in_size, stdin);
+                //skipping samples before next FFT (but fseek doesn't work for pipes)
+                for(int seek_remain=every_n_samples-fft_in_size;seek_remain>0;seek_remain-=the_bufsize)
+                {
+                    fread(temp_f, sizeof(complexf), MIN_M(the_bufsize,seek_remain), stdin);
+                }
+            }
+            else
+            {
+                //overlapped FFT
+                for(int i=0;i<fft_in_size-every_n_samples;i++) input[i]=input[i+every_n_samples];
+                fread(input+fft_in_size-every_n_samples, sizeof(float), every_n_samples, stdin);
+            }
+            //apply_window_c(input,windowed,fft_size,window);
+            apply_precalculated_window_f(input,windowed,fft_in_size,windowt);
+            fft_execute(plan);
+            if(octave)
+            {
+#if 0
+            // TODO
+                printf("fftdata=[");
+                //we have to swap the two parts of the array to get a valid spectrum
+                for(int i=fft_size/2;i<fft_size;i++) printf("(%g)+(%g)*i ",iof(output,i),qof(output,i));
+                for(int i=0;i<fft_size/2;i++) printf("(%g)+(%g)*i ",iof(output,i),qof(output,i));
+                printf(
+                    "];\n"
+                    "y=abs(fftdata);\n"
+                    "refreshdata;\n"
+                );
+#endif
+            }
+            else fwrite(output, sizeof(complexf), fft_out_size, stdout);
+            TRY_YIELD;
+        }
+    }
+
     if(!strcmp(argv[1],"none"))
     {
         return 0;

fft_fftw.h

@@ -22,6 +22,7 @@ struct fft_plan_s
 #include "libcsdr.h"
 
 FFT_PLAN_T* make_fft_c2c(int size, complexf* input, complexf* output, int forward, int benchmark);
+FFT_PLAN_T* make_fft_r2c(int size, float* input, complexf* output, int benchmark);
 void fft_execute(FFT_PLAN_T* plan);
 void fft_destroy(FFT_PLAN_T* plan);
 

libcsdr.c

@@ -1275,6 +1275,13 @@ void apply_precalculated_window_c(complexf* input, complexf* output, int size, f
     }
 }
 
+void apply_precalculated_window_f(float* input, float* output, int size, float *windowt)
+{
+	for(int i=0;i<size;i++) //@apply_precalculated_window_f
+	{
+		output[i] = input[i] * windowt[i];
+	}
+}
 
 void apply_window_f(float* input, float* output, int size, window_t window)
 {

libcsdr.h

@@ -142,6 +142,7 @@ void rational_resampler_get_lowpass_f(float* output, int output_size, int interp
 float *precalculate_window(int size, window_t window);
 void apply_window_c(complexf* input, complexf* output, int size, window_t window);
 void apply_precalculated_window_c(complexf* input, complexf* output, int size, float *windowt);
+void apply_precalculated_window_f(float* input, float* output, int size, float *windowt);
 void apply_window_f(float* input, float* output, int size, window_t window);
 void logpower_cf(complexf* input, float* output, int size, float add_db);
 void accumulate_power_cf(complexf* input, float* output, int size);

libcsdr_gpl.c

@@ -51,6 +51,33 @@ float shift_addition_cc(complexf *input, complexf* output, int input_size, shift
 	return starting_phase;
 }
 
+float shift_addition_fc(float *input, complexf* output, int input_size, shift_addition_data_t d, float starting_phase)
+{
+	//The original idea was taken from wdsp:
+	//http://svn.tapr.org/repos_sdr_hpsdr/trunk/W5WC/PowerSDR_HPSDR_mRX_PS/Source/wdsp/shift.c
+
+	//However, this method introduces noise (from floating point rounding errors), which increases until the end of the buffer.
+	//fprintf(stderr, "cosd=%g sind=%g\n", d.cosdelta, d.sindelta);
+	float cosphi=cos(starting_phase);
+	float sinphi=sin(starting_phase);
+	float cosphi_last, sinphi_last;
+	for(int i=0;i<input_size;i++) //@shift_addition_cc: work
+	{
+		iof(output,i)=cosphi*input[i];
+		qof(output,i)=sinphi*input[i];
+		//using the trigonometric addition formulas
+		//cos(phi+delta)=cos(phi)cos(delta)-sin(phi)*sin(delta)
+		cosphi_last=cosphi;
+		sinphi_last=sinphi;
+		cosphi=cosphi_last*d.cosdelta-sinphi_last*d.sindelta;
+		sinphi=sinphi_last*d.cosdelta+cosphi_last*d.sindelta;
+	}
+	starting_phase+=d.rate*PI*input_size;
+	while(starting_phase>PI) starting_phase-=2*PI; //@shift_addition_cc: normalize starting_phase
+	while(starting_phase<-PI) starting_phase+=2*PI;
+	return starting_phase;
+}
+
 shift_addition_data_t shift_addition_init(float rate)
 {
 	rate*=2;

libcsdr_gpl.h

@@ -31,6 +31,7 @@ typedef struct shift_addition_data_s
 } shift_addition_data_t;
 shift_addition_data_t shift_addition_init(float rate);
 float shift_addition_cc(complexf *input, complexf* output, int input_size, shift_addition_data_t d, float starting_phase);
+float shift_addition_fc(float *input, complexf* output, int input_size, shift_addition_data_t d, float starting_phase);
 void shift_addition_cc_test(shift_addition_data_t d);
 
 float agc_ff(float* input, float* output, int input_size, float reference, float attack_rate, float decay_rate, float max_gain, short hang_time, short attack_wait_time, float gain_filter_alpha, float last_gain);