--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.3/spandsp-0.0.3/tests/dc_restore_tests.c	Fri Jun 25 16:00:21 2010 +0200
@@ -0,0 +1,102 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * dc_restore_tests.c - Tests for the dc_restore functions.
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2001 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: dc_restore_tests.c,v 1.18 2006/11/19 14:07:26 steveu Exp $
+ */
+
+/*! \page dc_restore_tests_page DC restoration tests
+\section dc_restore_tests_page_sec_1 What does it do?
+*/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdlib.h>
+#include <inttypes.h>
+#include <stdio.h>
+#include <memory.h>
+#if defined(HAVE_TGMATH_H)
+#include <tgmath.h>
+#endif
+#if defined(HAVE_MATH_H)
+#include <math.h>
+#endif
+#include <time.h>
+#include <tiffio.h>
+
+#include "spandsp.h"
+    
+int main (int argc, char *argv[])
+{
+    awgn_state_t noise_source;
+    dc_restore_state_t dc_state;
+    int i;
+    int idum = 1234567;
+    int16_t dirty;
+    int16_t clean;
+    int estimate;
+    int min;
+    int max;
+    int dc_offset;
+
+    dc_offset = 5000;
+    awgn_init_dbm0(&noise_source, idum, -10.0);
+    dc_restore_init(&dc_state);
+    for (i = 0;  i < 100000;  i++)
+    {
+        dirty = awgn(&noise_source) + dc_offset;
+        clean = dc_restore(&dc_state, dirty);
+        if ((i % 1000) == 0)
+        {
+            printf("Sample %6d: %d (expect %d)\n",
+                   i,
+                   dc_restore_estimate(&dc_state),
+                   dc_offset);
+        }
+    }
+    /* We should have settled by now. Look at the variation we get */
+    min = 99999;
+    max = -99999;
+    for (i = 0;  i < 100000;  i++)
+    {
+        dirty = awgn(&noise_source) + dc_offset;
+        clean = dc_restore(&dc_state, dirty);
+        estimate = dc_restore_estimate(&dc_state);
+        if (estimate < min)
+            min = estimate;
+        if (estimate > max)
+            max = estimate;
+    }
+    printf("Spread of DC estimate for an offset of %d was %d to %d\n", dc_offset, min, max);
+    if (min < dc_offset - 50  ||  max > dc_offset + 50)
+    {
+        printf("Test failed.\n");
+        exit(2);
+    }
+    printf("Test passed.\n");
+    return  0;
+}
+/*- End of function --------------------------------------------------------*/
+/*- End of file ------------------------------------------------------------*/