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 26.073
22    ANSI-C code for the Adaptive Multi-Rate (AMR) speech codec
23    Available from http://www.3gpp.org
24
25(C) 2004, 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: /audio/gsm_amr/c/include/g_adapt.h
35
36     Date: 02/05/2002
37
38------------------------------------------------------------------------------
39 REVISION HISTORY
40
41 Description: Placed header file in the proper template format.  Added
42 parameter pOverflow for the basic math ops.
43
44 Description:  Replaced "int" and/or "char" with OSCL defined types.
45
46 Description: Moved _cplusplus #ifdef after Include section.
47
48 Description:
49
50------------------------------------------------------------------------------
51 INCLUDE DESCRIPTION
52
53 This file contains all the constant definitions and prototype definitions
54 needed by the file, g_adapt.c
55
56------------------------------------------------------------------------------
57*/
58
59/*----------------------------------------------------------------------------
60; CONTINUE ONLY IF NOT ALREADY DEFINED
61----------------------------------------------------------------------------*/
62#ifndef g_adapt_h
63#define g_adapt_h "$Id $"
64
65/*----------------------------------------------------------------------------
66; INCLUDES
67----------------------------------------------------------------------------*/
68#include "typedef.h"
69
70/*--------------------------------------------------------------------------*/
71#ifdef __cplusplus
72extern "C"
73{
74#endif
75
76    /*----------------------------------------------------------------------------
77    ; MACROS
78    ; Define module specific macros here
79    ----------------------------------------------------------------------------*/
80
81    /*----------------------------------------------------------------------------
82    ; DEFINES
83    ; Include all pre-processor statements here.
84    ----------------------------------------------------------------------------*/
85#define LTPG_MEM_SIZE 5 /* number of stored past LTP coding gains + 1 */
86
87    /*----------------------------------------------------------------------------
88    ; EXTERNAL VARIABLES REFERENCES
89    ; Declare variables used in this module but defined elsewhere
90    ----------------------------------------------------------------------------*/
91
92    /*----------------------------------------------------------------------------
93    ; SIMPLE TYPEDEF'S
94    ----------------------------------------------------------------------------*/
95
96    /*----------------------------------------------------------------------------
97    ; ENUMERATED TYPEDEF'S
98    ----------------------------------------------------------------------------*/
99
100    /*----------------------------------------------------------------------------
101    ; STRUCTURES TYPEDEF'S
102    ----------------------------------------------------------------------------*/
103    typedef struct
104    {
105        Word16 onset;                   /* onset state,                   Q0  */
106        Word16 prev_alpha;              /* previous adaptor output,       Q15 */
107        Word16 prev_gc;                 /* previous code gain,            Q1  */
108
109        Word16 ltpg_mem[LTPG_MEM_SIZE]; /* LTP coding gain history,       Q13 */
110        /* (ltpg_mem[0] not used for history) */
111    } GainAdaptState;
112
113    /*----------------------------------------------------------------------------
114    ; GLOBAL FUNCTION DEFINITIONS
115    ; Function Prototype declaration
116    ----------------------------------------------------------------------------*/
117    Word16 gain_adapt_init(GainAdaptState **st);
118    /* initialize one instance of the gain adaptor
119       Stores pointer to state struct in *st. This pointer has to
120       be passed to gain_adapt and gain_adapt_update in each call.
121       returns 0 on success
122     */
123
124    Word16 gain_adapt_reset(GainAdaptState *st);
125    /* reset of gain adaptor state (i.e. set state memory to zero)
126       returns 0 on success
127     */
128
129    void gain_adapt_exit(GainAdaptState **st);
130    /* de-initialize gain adaptor state (i.e. free state struct)
131       stores NULL in *st
132     */
133
134    /*************************************************************************
135     *
136     *  Function:   gain_adapt()
137     *  Purpose:    calculate pitch/codebook gain adaptation factor alpha
138     *              (and update the adaptor state)
139     *
140     **************************************************************************
141     */
142    void gain_adapt(
143        GainAdaptState *st,  /* i  : state struct                  */
144        Word16 ltpg,         /* i  : ltp coding gain (log2()), Q   */
145        Word16 gain_cod,     /* i  : code gain,                Q13 */
146        Word16 *alpha,       /* o  : gain adaptation factor,   Q15 */
147        Flag   *pOverflow    /* o  : overflow indicator            */
148    );
149
150    /*----------------------------------------------------------------------------
151    ; END
152    ----------------------------------------------------------------------------*/
153#ifdef __cplusplus
154}
155#endif
156
157#endif /* _H_ */
158
159
160