X-Git-Url: https://git.harvie.cz/?a=blobdiff_plain;f=c%2Fgoertzel%2Fgoertzel.c;h=96458a5b83c7cc2cacf5bd4536276df77c17221c;hb=8f751717d8307e3aa09fdfee19bed9478b7b16be;hp=f5250a0d11e2740e2a4e9987c0bae928c78796a1;hpb=59934436c41da5c999a065638d2e951a34110b03;p=mirrors%2FPrograms.git

diff --git a/c/goertzel/goertzel.c b/c/goertzel/goertzel.c
index f5250a0..96458a5 100644
--- a/c/goertzel/goertzel.c
+++ b/c/goertzel/goertzel.c
@@ -2,25 +2,8 @@
 #include <math.h>
 #include <getopt.h>
 
-
-/*
-	Usage examples
-	arecord | ./goertzel
-	sox input.mp3 -b 8 -c 1 -r 8000 -t wav - | ./goertzel
-
-	Arguments for DTMF decoding:
-	-f 697 -f 770 -f 852 -f 941 -f 1209 -f 1336 -f 1477 -f 1633 -t 10
-*/
-
 float goertzel_mag(int numSamples,int TARGET_FREQUENCY,int SAMPLING_RATE, float* data)
 {
-	/*
-		On lower samplerates and frame sizes this may perform sub-optimally. Eg.:
-		When set to detect 440Hz (at 8000Hz samplerate and ~4000 samples)
-		it actually detects something around 438,3Hz rather than 400Hz...
-		If you can't increase samplerate way around this is just to increase sensitivity.
-	*/
-
     int     k,i;
     float   floatnumSamples;
     float   omega,sine,cosine,coeff,q0,q1,q2,magnitude,real,imag;
@@ -54,7 +37,61 @@ float goertzel_mag(int numSamples,int TARGET_FREQUENCY,int SAMPLING_RATE, float*
 }
 
 void print_help(char ** argv) {
-	printf("help me %s\n", argv[0]);
+	printf(
+		"%s takes raw (wav) audio stream and computes power (or magnitude)\n"
+		"of desired frequencies using Goertzel algorithm for time frames\n"
+		"of fixed length (specified in samples or relative to sample rate).\n"
+		"This can be used in various frequency detection applications\n"
+		"like guitar tuning, DTMF decoding and many others...\n"
+		"\n"
+		"http://en.wikipedia.org/wiki/Goertzel_algorithm\n"
+		"\n"
+		"Curently only raw unsigned 8bit (u8) mono audio is supported, but\n"
+		"samplerate may vary. You can convert other formats before processing.\n"
+		"\n"
+		"On lower samplerates and frame sizes this may perform sub-optimally. Eg.:\n"
+		"When set to detect 440Hz (at 8000Hz samplerate and ~4000 samples)\n"
+		"it actually detects something around 438,3Hz rather than 400Hz...\n"
+		"If you can't increase samplerate way around this is just to increase sensitivity.\n"
+		"\n"
+		,argv[0]
+	);
+
+	printf(
+		"Arguments:\n"
+		"\t-i <file>\tInput from file (default STDIN)\n"
+		"\t-o <file>\tOutput to file (default STDOUT)\n"
+		"\t-a <file>\tOutput to file (append) (default STDOUT)\n"
+		"\n"
+		"\t-r <samplerate>\tInput samplerate (deault 8000 Hz)\n"
+		"\t-c <count>\tFrame size in samples (default 4000 Samples)\n"
+		"\t-d <ratio>\tFrame size (default 2) (samplerate will be divided by this number to get frame size same as -c)\n"
+		"\n"
+		"\t-f <freq>\tAdd frequency in Hz to detect (use multiple times, if no added 440 Hz will be...)\n"
+		"\n"
+		"\t-t <treshold>\tSet treshold (used to hide magnitudes lower than treshold) (defaults -1)\n"
+		"\t-n\t\tPrint integers rather than floats\n"
+		"\t-l\t\tDo not repeat values while still over treshold\n"
+		"\t-b\t\tDo not print first value that will fall under treshold\n"
+		"\t-q\t\tQuiet mode: print only values\n"
+		"\n"
+		"\t-?\t\tPrint help\n"
+		"\n"
+	);
+
+	printf(
+		"Usage examples:\n"
+		"\tarecord | %s\n"
+		"\tsox input.mp3 -b 8 -c 1 -r 8000 -t wav - | %s\n"
+		"\t%s -n -q -l -r 8000 -d 20 -t $tresh -f 697 [-f 770 ...]\n"
+		"\n"
+		,argv[0],argv[0],argv[0]
+	);
+
+	printf(
+		"Frequencies for DTMF decoding:\n"
+		"\t-f 697 -f 770 -f 852 -f 941 -f 1209 -f 1336 -f 1477 -f 1633 -t 10\n"
+	);
 }
 
 void addfreq(int *freqs, int freq) {
@@ -65,40 +102,49 @@ void addfreq(int *freqs, int freq) {
 }
 
 int main(int argc, char ** argv) {
-	/*
-	int samples[] = {0,1,2,3,4,5,6,7,8,9,8,7,6,5,4,3,2,1};
-	int samplecount = 18;
-	float power = goertzel(samplecount, samples, 1.2, 18);
-	printf("G: %f\n", power);
-	*/
-
 	int samplerate = 8000;
 	int samplecount = 4000;
 	int treshold = -1;
 	char noreturn = 0;
+	char repeat = 1;
 	char integers=0;
 	char verbose=1;
 	int freqs[argc+1]; freqs[0]=-1;
 
 	int opt;
-	while ((opt = getopt(argc, argv, "?r:s:f:t:iqn")) != -1) {
+	while ((opt = getopt(argc, argv, "?i:o:a:r:c:d:f:t:nlbq")) != -1) {
 		switch (opt) {
+			case 'i':
+				freopen(optarg, "r", stdin);
+				break;
+			case 'o':
+				freopen(optarg, "w", stdout);
+				break;
+			case 'a':
+				freopen(optarg, "a", stdout);
+				break;
 			case 'r':
 				samplerate = atoi(optarg);
 				break;
-			case 's':
+			case 'c':
 				samplecount = atoi(optarg);
 				break;
+			case 'd':
+				samplecount = samplerate/atoi(optarg);
+				break;
 			case 'f':
 				addfreq(freqs, atoi(optarg));
 				break;
 			case 't':
 				treshold = atoi(optarg);
 				break;
-			case 'i':
+			case 'n':
 				integers = 1;
 				break;
-			case 'n':
+			case 'l':
+				repeat = 0;
+				break;
+			case 'b':
 				noreturn = 1;
 				break;
 			case 'q':
@@ -152,7 +198,7 @@ int main(int argc, char ** argv) {
 
 			//Set print true if over treshold or if changed to false (print for the last time after going under treshold)
 			printnow = power[i] > treshold;
-			print = print || printnow || (printlast && !noreturn);
+			print = !(!repeat && printlast && !(!printnow)) && (print || printnow || (printlast && !noreturn));
 		}
 		printlast = printnow;
 		fflush(stdout);