1/* Copyright (c) 2008-2011 Octasic Inc.
2   Written by Jean-Marc Valin */
3/*
4   Redistribution and use in source and binary forms, with or without
5   modification, are permitted provided that the following conditions
6   are met:
7
8   - Redistributions of source code must retain the above copyright
9   notice, this list of conditions and the following disclaimer.
10
11   - Redistributions in binary form must reproduce the above copyright
12   notice, this list of conditions and the following disclaimer in the
13   documentation and/or other materials provided with the distribution.
14
15   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
18   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
19   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
20   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
21   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
22   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
23   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
24   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26*/
27
28#ifdef HAVE_CONFIG_H
29#include "config.h"
30#endif
31
32#include "opus_types.h"
33#include "opus_defines.h"
34
35#include <math.h>
36#include "mlp.h"
37#include "arch.h"
38#include "tansig_table.h"
39#define MAX_NEURONS 100
40
41#if 0
42static OPUS_INLINE opus_val16 tansig_approx(opus_val32 _x) /* Q19 */
43{
44	int i;
45	opus_val16 xx; /* Q11 */
46	/*double x, y;*/
47	opus_val16 dy, yy; /* Q14 */
48	/*x = 1.9073e-06*_x;*/
49	if (_x>=QCONST32(8,19))
50		return QCONST32(1.,14);
51	if (_x<=-QCONST32(8,19))
52		return -QCONST32(1.,14);
53	xx = EXTRACT16(SHR32(_x, 8));
54	/*i = lrint(25*x);*/
55	i = SHR32(ADD32(1024,MULT16_16(25, xx)),11);
56	/*x -= .04*i;*/
57	xx -= EXTRACT16(SHR32(MULT16_16(20972,i),8));
58	/*x = xx*(1./2048);*/
59	/*y = tansig_table[250+i];*/
60	yy = tansig_table[250+i];
61	/*y = yy*(1./16384);*/
62	dy = 16384-MULT16_16_Q14(yy,yy);
63	yy = yy + MULT16_16_Q14(MULT16_16_Q11(xx,dy),(16384 - MULT16_16_Q11(yy,xx)));
64	return yy;
65}
66#else
67/*extern const float tansig_table[501];*/
68static OPUS_INLINE float tansig_approx(float x)
69{
70	int i;
71	float y, dy;
72	float sign=1;
73	/* Tests are reversed to catch NaNs */
74    if (!(x<8))
75        return 1;
76    if (!(x>-8))
77        return -1;
78	if (x<0)
79	{
80	   x=-x;
81	   sign=-1;
82	}
83	i = (int)floor(.5f+25*x);
84	x -= .04f*i;
85	y = tansig_table[i];
86	dy = 1-y*y;
87	y = y + x*dy*(1 - y*x);
88	return sign*y;
89}
90#endif
91
92#if 0
93void mlp_process(const MLP *m, const opus_val16 *in, opus_val16 *out)
94{
95	int j;
96	opus_val16 hidden[MAX_NEURONS];
97	const opus_val16 *W = m->weights;
98	/* Copy to tmp_in */
99	for (j=0;j<m->topo[1];j++)
100	{
101		int k;
102		opus_val32 sum = SHL32(EXTEND32(*W++),8);
103		for (k=0;k<m->topo[0];k++)
104			sum = MAC16_16(sum, in[k],*W++);
105		hidden[j] = tansig_approx(sum);
106	}
107	for (j=0;j<m->topo[2];j++)
108	{
109		int k;
110		opus_val32 sum = SHL32(EXTEND32(*W++),14);
111		for (k=0;k<m->topo[1];k++)
112			sum = MAC16_16(sum, hidden[k], *W++);
113		out[j] = tansig_approx(EXTRACT16(PSHR32(sum,17)));
114	}
115}
116#else
117void mlp_process(const MLP *m, const float *in, float *out)
118{
119    int j;
120    float hidden[MAX_NEURONS];
121    const float *W = m->weights;
122    /* Copy to tmp_in */
123    for (j=0;j<m->topo[1];j++)
124    {
125        int k;
126        float sum = *W++;
127        for (k=0;k<m->topo[0];k++)
128            sum = sum + in[k]**W++;
129        hidden[j] = tansig_approx(sum);
130    }
131    for (j=0;j<m->topo[2];j++)
132    {
133        int k;
134        float sum = *W++;
135        for (k=0;k<m->topo[1];k++)
136            sum = sum + hidden[k]**W++;
137        out[j] = tansig_approx(sum);
138    }
139}
140#endif
141