From 58ebc152922055581c3f19c4ddd68c324059dbab Mon Sep 17 00:00:00 2001
From: Andreas Eversberg <jolly@eversberg.eu>
Date: Sun, 12 Feb 2017 07:35:05 +0100
Subject: [PATCH] Add test to measure performance of FM modulation and
 filtering

---
 .gitignore                  |  1 +
 src/test/Makefile.am        | 12 ++++++-
 src/test/test_performance.c | 67 +++++++++++++++++++++++++++++++++++++
 3 files changed, 79 insertions(+), 1 deletion(-)
 create mode 100644 src/test/test_performance.c

diff --git a/.gitignore b/.gitignore
index 4c188b3..a7cb155 100644
--- a/.gitignore
+++ b/.gitignore
@@ -32,3 +32,4 @@ src/test/test_compandor
 src/test/test_emphasis
 src/test/test_dms
 src/test/test_sms
+src/test/test_performance
diff --git a/src/test/Makefile.am b/src/test/Makefile.am
index eace0dc..eb50f7d 100644
--- a/src/test/Makefile.am
+++ b/src/test/Makefile.am
@@ -6,7 +6,8 @@ noinst_PROGRAMS = \
 	test_compandor \
 	test_emphasis \
 	test_dms \
-	test_sms
+	test_sms \
+	test_performance
 
 test_filter_SOURCES = test_filter.c dummy.c
 
@@ -57,3 +58,12 @@ test_sms_LDADD = \
 	$(UHD_LIBS) \
 	-lm
 
+test_performance_SOURCES = dummy.c test_performance.c
+
+test_performance_LDADD = \
+	$(COMMON_LA) \
+	$(top_builddir)/src/common/libcommon.a \
+	$(ALSA_LIBS) \
+	$(UHD_LIBS) \
+	-lm
+
diff --git a/src/test/test_performance.c b/src/test/test_performance.c
new file mode 100644
index 0000000..622df67
--- /dev/null
+++ b/src/test/test_performance.c
@@ -0,0 +1,67 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <math.h>
+#include <string.h>
+#include <sys/time.h>
+#include "../common/sample.h"
+#include "../common/filter.h"
+#include "../common/fm_modulation.h"
+#include "../common/debug.h"
+
+struct timeval start_tv, tv;
+double duration;
+int tot_samples;
+
+#define T_START() \
+	gettimeofday(&start_tv, NULL); \
+	tot_samples = 0; \
+	while (1) {
+
+#define T_STOP(what, samples) \
+		gettimeofday(&tv, NULL); \
+		duration = (double)tv.tv_sec + (double)tv.tv_usec / 1e6; \
+		duration -= (double)start_tv.tv_sec + (double)start_tv.tv_usec / 1e6; \
+		tot_samples += samples; \
+		if (duration >= 0.5) \
+			break; \
+	} \
+	printf("%s: %.3f mega samples/sec\n", what, (double)tot_samples / duration / 1e6); \
+
+
+#define SAMPLES 1000
+sample_t samples[SAMPLES];
+float buff[SAMPLES * 2];
+fm_mod_t mod;
+fm_demod_t demod;
+filter_t lp;
+
+int main(void)
+{
+	fm_mod_init(&mod, 50000, 0, 0.333);
+	T_START()
+	fm_modulate(&mod, samples, SAMPLES, buff);
+	T_STOP("FM modulate", SAMPLES)
+
+	fm_demod_init(&demod, 50000, 0, 10000.0);
+	T_START()
+	fm_demodulate(&demod, samples, SAMPLES, buff);
+	T_STOP("FM demodulate", SAMPLES)
+
+	filter_lowpass_init(&lp, 10000.0 / 2.0, 50000, 1);
+	T_START()
+	filter_process(&lp, samples, SAMPLES);
+	T_STOP("low-pass filter (second order)", SAMPLES)
+
+	filter_lowpass_init(&lp, 10000.0 / 2.0, 50000, 2);
+	T_START()
+	filter_process(&lp, samples, SAMPLES);
+	T_STOP("low-pass filter (fourth order)", SAMPLES)
+
+	filter_lowpass_init(&lp, 10000.0 / 2.0, 50000, 4);
+	T_START()
+	filter_process(&lp, samples, SAMPLES);
+	T_STOP("low-pass filter (eigth order)", SAMPLES)
+
+	return 0;
+}
+