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 26.073
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)
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: /audio/gsm_amr/c/src/include/lpc.h
35 
36      Date: 01/29/2002
37 
38 ------------------------------------------------------------------------------
39  REVISION HISTORY
40 
41  Description:  Replaced "int" and/or "char" with OSCL defined types.
42 
43  Description: Moved _cplusplus #ifdef after Include section.
44 
45  Description:
46 
47 ------------------------------------------------------------------------------
48  INCLUDE DESCRIPTION
49 
50       File             : lpc.h
51       Purpose          : 2 LP analyses centered at 2nd and 4th subframe
52                          for mode 12.2. For all other modes a
53                          LP analysis centered at 4th subframe is
54                          performed.
55 
56 ------------------------------------------------------------------------------
57 */
58 
59 #ifndef _LPC_H_
60 #define _LPC_H_
61 #define lpc_h "$Id $"
62 
63 /*----------------------------------------------------------------------------
64 ; INCLUDES
65 ----------------------------------------------------------------------------*/
66 #include "typedef.h"
67 #include "levinson.h"
68 #include "mode.h"
69 
70 
71 /*--------------------------------------------------------------------------*/
72 #ifdef __cplusplus
73 extern "C"
74 {
75 #endif
76 
77     /*----------------------------------------------------------------------------
78     ; MACROS
79     ; [Define module specific macros here]
80     ----------------------------------------------------------------------------*/
81 
82     /*----------------------------------------------------------------------------
83     ; DEFINES
84     ; [Include all pre-processor statements here.]
85     ----------------------------------------------------------------------------*/
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         LevinsonState *levinsonSt;
106     } lpcState;
107 
108 
109     /*----------------------------------------------------------------------------
110     ; GLOBAL FUNCTION DEFINITIONS
111     ; [List function prototypes here]
112     ----------------------------------------------------------------------------*/
113     Word16 lpc_init(lpcState **st);
114     /* initialize one instance of the pre processing state.
115        Stores pointer to filter status struct in *st. This pointer has to
116        be passed to lpc in each call.
117        returns 0 on success
118      */
119 
120     Word16 lpc_reset(lpcState *st);
121     /* reset of pre processing state (i.e. set state memory to zero)
122        returns 0 on success
123      */
124     void lpc_exit(lpcState **st);
125     /* de-initialize pre processing state (i.e. free status struct)
126        stores NULL in *st
127      */
128 
129     void lpc(
130         lpcState *st,     /* i/o: State struct                */
131         enum Mode mode,   /* i  : coder mode                  */
132         Word16 x[],       /* i  : Input signal           Q15  */
133         Word16 x_12k2[],  /* i  : Input signal (EFR)     Q15  */
134         Word16 a[],       /* o  : predictor coefficients Q12  */
135         Flag   *pOverflow
136     );
137 
138 
139 #ifdef __cplusplus
140 }
141 #endif
142 
143 #endif  /* _LPC_H_ */
144 
145 
146 
147 
148