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/****************************************************************************************
19Portions 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)
26Permission to distribute, modify and use this file under the standard license
27terms listed above has been obtained from the copyright holder.
28****************************************************************************************/
29/*
30------------------------------------------------------------------------------
31
32
33
34 Filename: scale_signal.cpp
35
36     Date: 05/08/2004
37
38------------------------------------------------------------------------------
39 REVISION HISTORY
40
41
42 Description:
43
44------------------------------------------------------------------------------
45 INPUT AND OUTPUT DEFINITIONS
46
47     int16 signal[],             (i/o) : signal to scale
48     int16 lg,                   (i)   : size of x[]
49     int16 exp                   (i)   : exponent: x = round(x << exp)
50
51------------------------------------------------------------------------------
52 FUNCTION DESCRIPTION
53
54   Scale signal to get maximum of dynamic range
55
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 "pv_amr_wb_type_defs.h"
76#include "pvamrwbdecoder_basic_op.h"
77#include "pvamrwbdecoder_acelp.h"
78
79/*----------------------------------------------------------------------------
80; MACROS
81; Define module specific macros here
82----------------------------------------------------------------------------*/
83
84
85/*----------------------------------------------------------------------------
86; DEFINES
87; Include all pre-processor statements here. Include conditional
88; compile variables also.
89----------------------------------------------------------------------------*/
90
91/*----------------------------------------------------------------------------
92; LOCAL FUNCTION DEFINITIONS
93; Function Prototype declaration
94----------------------------------------------------------------------------*/
95
96/*----------------------------------------------------------------------------
97; LOCAL STORE/BUFFER/POINTER DEFINITIONS
98; Variable declaration - defined here and used outside this module
99----------------------------------------------------------------------------*/
100
101/*----------------------------------------------------------------------------
102; EXTERNAL FUNCTION REFERENCES
103; Declare functions defined elsewhere and referenced in this module
104----------------------------------------------------------------------------*/
105
106/*----------------------------------------------------------------------------
107; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES
108; Declare variables used in this module but defined elsewhere
109----------------------------------------------------------------------------*/
110
111/*----------------------------------------------------------------------------
112; FUNCTION CODE
113----------------------------------------------------------------------------*/
114
115void scale_signal(
116    int16 x[],              /* (i/o) : signal to scale               */
117    int16 lg,               /* (i)   : size of x[]                   */
118    int16 exp               /* (i)   : exponent: x = round(x << exp) */
119)
120{
121    int16 i;
122    int16 tmp;
123    int16 *pt_x;
124
125
126    int32 L_tmp;
127
128
129    if (exp > 0)
130    {
131        for (i = 0; i < lg; i++)
132        {
133            L_tmp = shl_int32(((int32)x[i] << 16), exp);       /* saturation can occur here */
134            x[i] = amr_wb_round(L_tmp);
135        }
136    }
137    else if (exp < 0)
138    {
139        exp = -exp;
140        exp &= 0xf;
141        tmp = (int16)(0x00008000 >> (16 - exp));
142        pt_x = x;
143
144        for (i = lg >> 1; i != 0; i--)
145        {
146            *(pt_x)   = add_int16(*(pt_x), tmp) >> exp;
147            pt_x++;
148            *(pt_x)   = add_int16(*(pt_x), tmp) >> exp;
149            pt_x++;
150        }
151
152    }
153    return;
154}
155