--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.6pre17/src/spandsp/bert.h	Fri Jun 25 15:50:58 2010 +0200
@@ -0,0 +1,162 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * bert.h - Bit error rate tests.
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2004 Steve Underwood
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1,
+ * 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id: bert.h,v 1.23 2009/02/10 13:06:47 steveu Exp $
+ */
+
+#if !defined(_SPANDSP_BERT_H_)
+#define _SPANDSP_BERT_H_
+
+/*! \page bert_page The Bit Error Rate tester
+\section bert_page_sec_1 What does it do?
+The Bit Error Rate tester generates a pseudo random bit stream. It also accepts such
+a pattern, synchronises to it, and checks the bit error rate in this stream.
+
+\section bert_page_sec_2 How does it work?
+The Bit Error Rate tester generates a bit stream, with a repeating 2047 bit pseudo
+random pattern, using an 11 stage polynomial generator. It also accepts such a pattern,
+synchronises to it, and checks the bit error rate in this stream. If the error rate is
+excessive the tester assumes synchronisation has been lost, and it attempts to
+resynchronise with the stream.
+
+The bit error rate is continuously assessed against decadic ranges -
+    > 1 in 10^2
+    > 1 in 10^3
+    > 1 in 10^4
+    > 1 in 10^5
+    > 1 in 10^6
+    > 1 in 10^7
+    < 1 in 10^7
+To ensure fairly smooth results from this assessment, each decadic level is assessed
+over 10/error rate bits. That is, to assess if the signal's BER is above or below 1 in 10^5
+the software looks over 10*10^5 => 10^6 bits.
+*/
+
+enum
+{
+    BERT_REPORT_SYNCED = 0,
+    BERT_REPORT_UNSYNCED,
+    BERT_REPORT_REGULAR,
+    BERT_REPORT_GT_10_2,
+    BERT_REPORT_LT_10_2,
+    BERT_REPORT_LT_10_3,
+    BERT_REPORT_LT_10_4,
+    BERT_REPORT_LT_10_5,
+    BERT_REPORT_LT_10_6,
+    BERT_REPORT_LT_10_7
+};
+
+/* The QBF strings should be:
+    "VoyeZ Le BricK GeanT QuE J'ExaminE PreS Du WharF 123 456 7890 + - * : = $ % ( )"
+    "ThE QuicK BrowN FoX JumpS OveR ThE LazY DoG 123 456 7890 + - * : = $ % ( )"
+*/
+
+enum
+{
+    BERT_PATTERN_ZEROS = 0,
+    BERT_PATTERN_ONES,
+    BERT_PATTERN_7_TO_1,
+    BERT_PATTERN_3_TO_1,
+    BERT_PATTERN_1_TO_1,
+    BERT_PATTERN_1_TO_3,
+    BERT_PATTERN_1_TO_7,
+    BERT_PATTERN_QBF,
+    BERT_PATTERN_ITU_O151_23,
+    BERT_PATTERN_ITU_O151_20,
+    BERT_PATTERN_ITU_O151_15,
+    BERT_PATTERN_ITU_O152_11,
+    BERT_PATTERN_ITU_O153_9
+};
+
+/*!
+    Bit error rate tester (BERT) results descriptor. This is used to report the
+    results of a BER test.
+*/
+typedef struct
+{
+    int total_bits;
+    int bad_bits;
+    int resyncs;
+} bert_results_t;
+
+typedef void (*bert_report_func_t)(void *user_data, int reason, bert_results_t *bert_results);
+
+/*!
+    Bit error rate tester (BERT) descriptor. This defines the working state for a
+    single instance of the BERT.
+*/
+typedef struct bert_state_s bert_state_t;
+
+#if defined(__cplusplus)
+extern "C"
+{
+#endif
+
+/*! Return a short description of a BERT event.
+    \param event The event type.
+    \return A pointer to a short text string describing the event. */
+SPAN_DECLARE(const char *) bert_event_to_str(int event);
+
+/*! Initialise a BERT context.
+    \param s The BERT context.
+    \param limit The maximum test duration.
+    \param pattern One of the supported BERT signal patterns.
+    \param resync_len ???
+    \param resync_percent The percentage of bad bits which will cause a resync.
+    \return The BERT context. */
+SPAN_DECLARE(bert_state_t *) bert_init(bert_state_t *s, int limit, int pattern, int resync_len, int resync_percent);
+
+SPAN_DECLARE(int) bert_release(bert_state_t *s);
+
+SPAN_DECLARE(int) bert_free(bert_state_t *s);
+
+/*! Get the next bit of the BERT sequence from the generator.
+    \param s The BERT context.
+    \return The bit. */
+SPAN_DECLARE(int) bert_get_bit(bert_state_t *s);
+
+/*! Put the next bit of the BERT sequence to the analyser.
+    \param s The BERT context.
+    \param bit The bit. */
+SPAN_DECLARE(void) bert_put_bit(bert_state_t *s, int bit);
+
+/*! Set the callback function for reporting the test status.
+    \param s The BERT context.
+    \param freq The required frequency of regular reports.
+    \param reporter The callback function.
+    \param user_data An opaque pointer passed to the reporter routine. */
+SPAN_DECLARE(void) bert_set_report(bert_state_t *s, int freq, bert_report_func_t reporter, void *user_data);
+
+/*! Get the results of the BERT.
+    \param s The BERT context.
+    \param results The results.
+    \return The size of the result structure. */
+SPAN_DECLARE(int) bert_result(bert_state_t *s, bert_results_t *results);
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif
+/*- End of file ------------------------------------------------------------*/