--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.6pre17/tests/dds_tests.c	Fri Jun 25 15:50:58 2010 +0200
@@ -0,0 +1,219 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * dds_tests.c
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2003 Steve Underwood
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id: dds_tests.c,v 1.26 2009/06/02 14:55:36 steveu Exp $
+ */
+
+/*! \file */
+
+/*! \page dds_tests_page Direct digital synthesis tests
+\section dds_tests_page_sec_1 What does it do?
+???.
+
+\section dds_tests_page_sec_2 How does it work?
+???.
+*/
+
+#if defined(HAVE_CONFIG_H)
+#include "config.h"
+#endif
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <memory.h>
+#include <sndfile.h>
+
+#include "spandsp.h"
+#include "spandsp-sim.h"
+
+#define OUTPUT_FILE_NAME            "dds.wav"
+#define OUTPUT_FILE_NAME_COMPLEX    "complex_dds.wav"
+
+#define SAMPLES_PER_CHUNK           8000
+
+int main(int argc, char *argv[])
+{
+    int i;
+    uint32_t phase;
+    int32_t phase_inc;
+    int outframes;
+    complexf_t camp;
+    int16_t buf[2*SAMPLES_PER_CHUNK];
+    SNDFILE *outhandle;
+    power_meter_t meter;
+    power_meter_t meter_i;
+    power_meter_t meter_q;
+    int scale;
+
+    power_meter_init(&meter, 10);
+
+    printf("Non-complex DDS tests.\n");
+    if ((outhandle = sf_open_telephony_write(OUTPUT_FILE_NAME, 1)) == NULL)
+    {
+        fprintf(stderr, "    Cannot create audio file '%s'\n", OUTPUT_FILE_NAME);
+        exit(2);
+    }
+
+    phase = 0;
+
+    printf("Test with 123.456789Hz.\n");
+    phase_inc = dds_phase_rate(123.456789f);
+    scale = dds_scaling_dbm0(-10.0f);
+    for (i = 0;  i < SAMPLES_PER_CHUNK;  i++)
+    {
+        buf[i] = alaw_to_linear(linear_to_alaw((dds(&phase, phase_inc)*scale) >> 15));
+        power_meter_update(&meter, buf[i]);
+    }
+    outframes = sf_writef_short(outhandle, buf, SAMPLES_PER_CHUNK);
+    if (outframes != SAMPLES_PER_CHUNK)
+    {
+        fprintf(stderr, "    Error writing audio file\n");
+        exit(2);
+    }
+    printf("Level is %fdBOv/%fdBm0\n", power_meter_current_dbov(&meter), power_meter_current_dbm0(&meter));
+    if (fabs(power_meter_current_dbm0(&meter) + 10.0f) > 0.05f)
+    {
+        printf("Test failed.\n");
+        exit(2);
+    }
+
+    printf("Test with 12.3456789Hz.\n");
+    phase_inc = dds_phase_rate(12.3456789f);
+    for (i = 0;  i < SAMPLES_PER_CHUNK;  i++)
+    {
+        buf[i] = alaw_to_linear(linear_to_alaw(dds(&phase, phase_inc)));
+        power_meter_update(&meter, buf[i]);
+    }
+    outframes = sf_writef_short(outhandle, buf, SAMPLES_PER_CHUNK);
+    if (outframes != SAMPLES_PER_CHUNK)
+    {
+        fprintf(stderr, "    Error writing audio file\n");
+        exit(2);
+    }
+    printf("Level is %fdBOv/%fdBm0\n", power_meter_current_dbov(&meter), power_meter_current_dbm0(&meter));
+    /* Use a wider tolerance for this very low frequency - the power meter will ripple */
+    if (fabs(power_meter_current_dbov(&meter) + 3.02f) > 0.2f)
+    {
+        printf("Test failed.\n");
+        exit(2);
+    }
+
+    printf("Test with 2345.6789Hz.\n");
+    phase_inc = dds_phase_rate(2345.6789f);
+    scale = dds_scaling_dbov(-10.0f);
+    for (i = 0;  i < SAMPLES_PER_CHUNK;  i++)
+    {
+        buf[i] = alaw_to_linear(linear_to_alaw((dds(&phase, phase_inc)*scale) >> 15));
+        power_meter_update(&meter, buf[i]);
+    }
+    outframes = sf_writef_short(outhandle, buf, SAMPLES_PER_CHUNK);
+    if (outframes != SAMPLES_PER_CHUNK)
+    {
+        fprintf(stderr, "    Error writing audio file\n");
+        exit(2);
+    }
+    printf("Level is %fdBOv/%fdBm0\n", power_meter_current_dbov(&meter), power_meter_current_dbm0(&meter));
+    if (fabs(power_meter_current_dbov(&meter) + 10.0f) > 0.05f)
+    {
+        printf("Test failed.\n");
+        exit(2);
+    }
+
+    printf("Test with 3456.789Hz.\n");
+    phase_inc = dds_phase_rate(3456.789f);
+    for (i = 0;  i < SAMPLES_PER_CHUNK;  i++)
+    {
+        buf[i] = alaw_to_linear(linear_to_alaw(dds(&phase, phase_inc)));
+        power_meter_update(&meter, buf[i]);
+    }
+    outframes = sf_writef_short(outhandle, buf, SAMPLES_PER_CHUNK);
+    if (outframes != SAMPLES_PER_CHUNK)
+    {
+        fprintf(stderr, "    Error writing audio file\n");
+        exit(2);
+    }
+    printf("Level is %fdBOv/%fdBm0\n", power_meter_current_dbov(&meter), power_meter_current_dbm0(&meter));
+    if (fabs(power_meter_current_dbov(&meter) + 3.02f) > 0.05f)
+    {
+        printf("Test failed.\n");
+        exit(2);
+    }
+
+    if (sf_close(outhandle) != 0)
+    {
+        fprintf(stderr, "    Cannot close audio file '%s'\n", OUTPUT_FILE_NAME);
+        exit(2);
+    }
+
+    printf("Complex DDS tests,\n");
+    if ((outhandle = sf_open_telephony_write(OUTPUT_FILE_NAME_COMPLEX, 2)) == NULL)
+    {
+        fprintf(stderr, "    Cannot create audio file '%s'\n", OUTPUT_FILE_NAME_COMPLEX);
+        exit(2);
+    }
+
+    power_meter_init(&meter_i, 7);
+    power_meter_init(&meter_q, 7);
+
+    phase = 0;
+    phase_inc = dds_phase_ratef(123.456789f);
+    for (i = 0;  i < SAMPLES_PER_CHUNK;  i++)
+    {
+        camp = dds_complexf(&phase, phase_inc);
+        buf[2*i] = camp.re*10000.0f;
+        buf[2*i + 1] = camp.im*10000.0f;
+        power_meter_update(&meter_i, buf[2*i]);
+        power_meter_update(&meter_q, buf[2*i]);
+    }
+    outframes = sf_writef_short(outhandle, buf, SAMPLES_PER_CHUNK);
+    if (outframes != SAMPLES_PER_CHUNK)
+    {
+        fprintf(stderr, "    Error writing audio file\n");
+        exit(2);
+    }
+    printf("Level is %fdBOv/%fdBm0, %fdBOv/%fdBm0\n",
+           power_meter_current_dbov(&meter_i),
+           power_meter_current_dbm0(&meter_i),
+           power_meter_current_dbov(&meter_q),
+           power_meter_current_dbm0(&meter_q));
+    if (fabs(power_meter_current_dbov(&meter_i) + 13.42f) > 0.05f
+        ||
+        fabs(power_meter_current_dbov(&meter_q) + 13.42f) > 0.05f)
+    {
+        printf("Test failed.\n");
+        exit(2);
+    }
+
+    if (sf_close(outhandle) != 0)
+    {
+        fprintf(stderr, "    Cannot close audio file '%s'\n", OUTPUT_FILE_NAME_COMPLEX);
+        exit(2);
+    }
+
+    printf("Tests passed.\n");
+    return  0;
+}
+/*- End of function --------------------------------------------------------*/
+/*- End of file ------------------------------------------------------------*/