1/*---------------------------------------------------------------------------*
2 *  voicing.c  *
3 *                                                                           *
4 *  Copyright 2007, 2008 Nuance Communciations, Inc.                               *
5 *                                                                           *
6 *  Licensed under the Apache License, Version 2.0 (the 'License');          *
7 *  you may not use this file except in compliance with the License.         *
8 *                                                                           *
9 *  You may obtain a copy of the License at                                  *
10 *      http://www.apache.org/licenses/LICENSE-2.0                           *
11 *                                                                           *
12 *  Unless required by applicable law or agreed to in writing, software      *
13 *  distributed under the License is distributed on an 'AS IS' BASIS,        *
14 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. *
15 *  See the License for the specific language governing permissions and      *
16 *  limitations under the License.                                           *
17 *                                                                           *
18 *---------------------------------------------------------------------------*/
19
20
21
22#include <stdlib.h>
23#include <string.h>
24#include <math.h>
25#include <assert.h>
26
27#include <limits.h>
28#ifndef _RTT
29#include <stdio.h>
30#endif
31
32#include "all_defs.h"
33#include "voicing.h"
34
35#include "portable.h"
36
37#include "../cfront/sh_down.h"
38
39#define DEBUG        0
40
41
42static const char voicing[] = "$Id: voicing.c,v 1.1.10.5 2007/10/15 18:06:24 dahan Exp $";
43
44
45void init_voicing_analysis(voicing_info *chan)
46{
47  chan->count = -1;
48  chan->sil_count = 0;
49  chan->speech_count = 0;
50  chan->fast_count = 0;
51#if DEBUG
52  log_report("U: 255 255 255 -1 -1 -1 -1\n");
53#endif
54  return;
55}
56
57long voicing_analysis(voicing_info *chan, voicedata enval , int* log)
58{
59  long  retval;
60  int   threshold;
61
62  if (chan->count < 0)
63  {
64    chan->b1 = SHIFT_UP(enval, 8);
65    chan->b0 = SHIFT_UP(enval, 8);
66    chan->count = -1;
67  }
68
69  /*  background level
70  */
71  if (chan->b0 > SHIFT_UP(enval, 8))
72  {
73    chan->b0 = SHIFT_UP(enval, 8);
74    chan->count = 0;
75  }
76  if (chan->count > B0_HANG2)
77    chan->b0 += B0_RATE2;
78  else if (chan->count > B0_HANG1)
79    chan->b0 += B0_RATE1;
80
81  chan->count++;
82
83  /*  the second background level
84  */
85  if ((enval - chan->quiet_margin) < (chan->b0 >> 8))
86    chan->b1 += SHIFT_DOWN(B1_RATE * (SHIFT_UP(enval, 8) - chan->b1), 8);
87
88  /*  speech level
89  */
90  if (chan->s0 < SHIFT_UP(enval, 8))
91    chan->s0 = SHIFT_UP(enval, 8);
92  else
93    chan->s0 -= B0_RATE1;
94
95  /*  increase the range by 25% */
96  threshold = (chan->b1 + (SHIFT_DOWN(
97                             MAX(chan->s0 - chan->b0 - DYNAMIC_RANGE, 0), 2))) >> 8;
98
99  /*  Is it speech?
100  */
101  if (enval > (threshold + chan->margin))
102    chan->speech_count++;
103  else
104    chan->speech_count = 0;
105
106  /*  Is it Fast-match speech
107  */
108  if (enval > (threshold + chan->fast_margin))
109    chan->fast_count++;
110  else
111    chan->fast_count = 0;
112
113  if (enval <= (threshold + chan->quiet_margin))
114    chan->sil_count++;
115  else
116    chan->sil_count = 0;
117
118  /*******************
119   * Returning flags *
120   *******************/
121
122  retval = 0L;
123
124  if (chan->fast_count > chan->voice_duration)
125    retval = FAST_VOICE_BIT;
126  else if (chan->sil_count > chan->quiet_duration)
127    retval = QUIET_BIT;
128
129  if (chan->speech_count > chan->voice_duration)
130    retval |= VOICE_BIT;
131
132  if (chan->sil_count > 0)
133    retval |= BELOW_THRESHOLD_BIT;
134
135  chan->voice_status = retval;
136#if DEBUG
137  log_report("U: %d %.1f %.1f, %d %d %d %d\n", (int) enval,
138             chan->b0 / 256.0, chan->b1 / 256.0,
139             chan->speech_count, chan->fast_count,
140             chan->sil_count, chan->count);
141#endif
142  return (retval);
143}
144