1 /* ------------------------------------------------------------------
2 * Copyright (C) 1998-2009 PacketVideo
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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
14 * See the License for the specific language governing permissions
15 * and limitations under the License.
16 * -------------------------------------------------------------------
18 /****************************************************************************************
19 Portions of this file are derived from the following 3GPP standard:
22 ANSI-C code for the Adaptive Multi-Rate (AMR) speech codec
23 Available from http://www.3gpp.org
25 (C) 2004, 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 ****************************************************************************************/
30 ------------------------------------------------------------------------------
36 ------------------------------------------------------------------------------
39 This file contains all the constant definitions and prototype definitions
40 needed by the file, g_adapt.c
42 ------------------------------------------------------------------------------
45 /*----------------------------------------------------------------------------
46 ; CONTINUE ONLY IF NOT ALREADY DEFINED
47 ----------------------------------------------------------------------------*/
49 #define g_adapt_h "$Id $"
51 /*----------------------------------------------------------------------------
53 ----------------------------------------------------------------------------*/
56 /*--------------------------------------------------------------------------*/
62 /*----------------------------------------------------------------------------
64 ; Define module specific macros here
65 ----------------------------------------------------------------------------*/
67 /*----------------------------------------------------------------------------
69 ; Include all pre-processor statements here.
70 ----------------------------------------------------------------------------*/
71 #define LTPG_MEM_SIZE 5 /* number of stored past LTP coding gains + 1 */
73 /*----------------------------------------------------------------------------
74 ; EXTERNAL VARIABLES REFERENCES
75 ; Declare variables used in this module but defined elsewhere
76 ----------------------------------------------------------------------------*/
78 /*----------------------------------------------------------------------------
80 ----------------------------------------------------------------------------*/
82 /*----------------------------------------------------------------------------
83 ; ENUMERATED TYPEDEF'S
84 ----------------------------------------------------------------------------*/
86 /*----------------------------------------------------------------------------
87 ; STRUCTURES TYPEDEF'S
88 ----------------------------------------------------------------------------*/
91 Word16 onset; /* onset state, Q0 */
92 Word16 prev_alpha; /* previous adaptor output, Q15 */
93 Word16 prev_gc; /* previous code gain, Q1 */
95 Word16 ltpg_mem[LTPG_MEM_SIZE]; /* LTP coding gain history, Q13 */
96 /* (ltpg_mem[0] not used for history) */
99 /*----------------------------------------------------------------------------
100 ; GLOBAL FUNCTION DEFINITIONS
101 ; Function Prototype declaration
102 ----------------------------------------------------------------------------*/
103 Word16 gain_adapt_init(GainAdaptState **st);
104 /* initialize one instance of the gain adaptor
105 Stores pointer to state struct in *st. This pointer has to
106 be passed to gain_adapt and gain_adapt_update in each call.
110 Word16 gain_adapt_reset(GainAdaptState *st);
111 /* reset of gain adaptor state (i.e. set state memory to zero)
115 void gain_adapt_exit(GainAdaptState **st);
116 /* de-initialize gain adaptor state (i.e. free state struct)
120 /*************************************************************************
122 * Function: gain_adapt()
123 * Purpose: calculate pitch/codebook gain adaptation factor alpha
124 * (and update the adaptor state)
126 **************************************************************************
129 GainAdaptState *st, /* i : state struct */
130 Word16 ltpg, /* i : ltp coding gain (log2()), Q */
131 Word16 gain_cod, /* i : code gain, Q13 */
132 Word16 *alpha, /* o : gain adaptation factor, Q15 */
133 Flag *pOverflow /* o : overflow indicator */
136 /*----------------------------------------------------------------------------
138 ----------------------------------------------------------------------------*/