1 /* ------------------------------------------------------------------
2 * Copyright (C) 1998-2009 PacketVideo
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
13 * express or implied.
14 * See the License for the specific language governing permissions
15 * and limitations under the License.
16 * -------------------------------------------------------------------
17 */
18 /****************************************************************************************
19 Portions of this file are derived from the following 3GPP standard:
20
21 3GPP TS 26.173
22 ANSI-C code for the Adaptive Multi-Rate - Wideband (AMR-WB) speech codec
23 Available from http://www.3gpp.org
24
25 (C) 2007, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC)
26 Permission to distribute, modify and use this file under the standard license
27 terms listed above has been obtained from the copyright holder.
28 ****************************************************************************************/
29 /*
30 ------------------------------------------------------------------------------
31
32
33
34 Filename: agc2_amr_wb.cpp
35
36 Date: 05/08/2007
37
38 ------------------------------------------------------------------------------
39 REVISION HISTORY
40
41
42 Description:
43
44 ------------------------------------------------------------------------------
45 INPUT AND OUTPUT DEFINITIONS
46
47 int16 * sig_in, (i) : postfilter input signal
48 int16 * sig_out, (i/o) : postfilter output signal
49 int16 l_trm (i) : subframe size
50
51
52 ------------------------------------------------------------------------------
53 FUNCTION DESCRIPTION
54
55 Performs adaptive gain control
56
57 ------------------------------------------------------------------------------
58 REQUIREMENTS
59
60
61 ------------------------------------------------------------------------------
62 REFERENCES
63
64 ------------------------------------------------------------------------------
65 PSEUDO-CODE
66
67 ------------------------------------------------------------------------------
68 */
69
70
71 /*----------------------------------------------------------------------------
72 ; INCLUDES
73 ----------------------------------------------------------------------------*/
74
75 #include "pvamrwbdecoder_cnst.h"
76 #include "pvamrwbdecoder_acelp.h"
77 #include "pv_amr_wb_type_defs.h"
78 #include "pvamrwbdecoder_basic_op.h"
79 #include "pvamrwb_math_op.h"
80
81 /*----------------------------------------------------------------------------
82 ; MACROS
83 ; Define module specific macros here
84 ----------------------------------------------------------------------------*/
85
86
87 /*----------------------------------------------------------------------------
88 ; DEFINES
89 ; Include all pre-processor statements here. Include conditional
90 ; compile variables also.
91 ----------------------------------------------------------------------------*/
92
93 /*----------------------------------------------------------------------------
94 ; LOCAL FUNCTION DEFINITIONS
95 ; Function Prototype declaration
96 ----------------------------------------------------------------------------*/
97
98 /*----------------------------------------------------------------------------
99 ; LOCAL STORE/BUFFER/POINTER DEFINITIONS
100 ; Variable declaration - defined here and used outside this module
101 ----------------------------------------------------------------------------*/
102
103 /*----------------------------------------------------------------------------
104 ; EXTERNAL FUNCTION REFERENCES
105 ; Declare functions defined elsewhere and referenced in this module
106 ----------------------------------------------------------------------------*/
107
108 /*----------------------------------------------------------------------------
109 ; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES
110 ; Declare variables used in this module but defined elsewhere
111 ----------------------------------------------------------------------------*/
112
113 /*----------------------------------------------------------------------------
114 ; FUNCTION CODE
115 ----------------------------------------------------------------------------*/
116
agc2_amr_wb(int16 * sig_in,int16 * sig_out,int16 l_trm)117 void agc2_amr_wb(
118 int16 * sig_in, /* (i) : postfilter input signal */
119 int16 * sig_out, /* (i/o) : postfilter output signal */
120 int16 l_trm /* (i) : subframe size */
121 )
122 {
123
124 int16 i, exp;
125 int16 gain_in, gain_out, g0;
126 int32 s;
127
128 int16 temp;
129
130 /* calculate gain_out with exponent */
131
132 temp = sig_out[0] >> 2;
133 s = fxp_mul_16by16(temp, temp) << 1;
134 for (i = 1; i < l_trm; i++)
135 {
136 temp = sig_out[i] >> 2;
137 s = mac_16by16_to_int32(s, temp, temp);
138 }
139
140
141 if (s == 0)
142 {
143 return;
144 }
145 exp = normalize_amr_wb(s) - 1;
146 gain_out = amr_wb_round(s << exp);
147
148 /* calculate gain_in with exponent */
149
150 temp = sig_in[0] >> 2;
151 s = mul_16by16_to_int32(temp, temp);
152 for (i = 1; i < l_trm; i++)
153 {
154 temp = sig_in[i] >> 2;
155 s = mac_16by16_to_int32(s, temp, temp);
156 }
157
158
159 if (s == 0)
160 {
161 g0 = 0;
162 }
163 else
164 {
165 i = normalize_amr_wb(s);
166 gain_in = amr_wb_round(s << i);
167 exp -= i;
168
169 /*
170 * g0 = sqrt(gain_in/gain_out)
171 */
172
173 s = div_16by16(gain_out, gain_in);
174 s = shl_int32(s, 7); /* s = gain_out / gain_in */
175 s = shr_int32(s, exp); /* add exponent */
176
177 s = one_ov_sqrt(s);
178 g0 = amr_wb_round(shl_int32(s, 9));
179 }
180 /* sig_out(n) = gain(n) sig_out(n) */
181
182 for (i = 0; i < l_trm; i++)
183 {
184 sig_out[i] = extract_h(shl_int32(fxp_mul_16by16(sig_out[i], g0), 3));
185
186 }
187
188 return;
189 }
190
191