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/include/preemph.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, preemph.c
55 
56 ------------------------------------------------------------------------------
57 */
58 
59 /*----------------------------------------------------------------------------
60 ; CONTINUE ONLY IF NOT ALREADY DEFINED
61 ----------------------------------------------------------------------------*/
62 #ifndef preemph_h
63 #define preemph_h "$Id $"
64 
65 
66 /*----------------------------------------------------------------------------
67 ; INCLUDES
68 ----------------------------------------------------------------------------*/
69 
70 #include "typedef.h"
71 
72 /*--------------------------------------------------------------------------*/
73 #ifdef __cplusplus
74 extern "C"
75 {
76 #endif
77 
78     /*----------------------------------------------------------------------------
79     ; MACROS
80     ; Define module specific macros here
81     ----------------------------------------------------------------------------*/
82 
83     /*----------------------------------------------------------------------------
84     ; DEFINES
85     ; Include all pre-processor statements here.
86     ----------------------------------------------------------------------------*/
87 
88     /*----------------------------------------------------------------------------
89     ; EXTERNAL VARIABLES REFERENCES
90     ; Declare variables used in this module but defined elsewhere
91     ----------------------------------------------------------------------------*/
92 
93     /*----------------------------------------------------------------------------
94     ; SIMPLE TYPEDEF'S
95     ----------------------------------------------------------------------------*/
96 
97     /*----------------------------------------------------------------------------
98     ; ENUMERATED TYPEDEF'S
99     ----------------------------------------------------------------------------*/
100 
101     /*----------------------------------------------------------------------------
102     ; STRUCTURES TYPEDEF'S
103     ----------------------------------------------------------------------------*/
104     typedef struct
105     {
106         Word16 mem_pre;          /* filter state */
107     } preemphasisState;
108 
109     /*----------------------------------------------------------------------------
110     ; GLOBAL FUNCTION DEFINITIONS
111     ; Function Prototype declaration
112     ----------------------------------------------------------------------------*/
113 
114     Word16 preemphasis_reset(preemphasisState *st);
115     /* reset of preemphasis filter (i.e. set state memory to zero)
116        returns 0 on success
117      */
118     void preemphasis_exit(preemphasisState **st);
119     /* de-initialize preemphasis filter (i.e. free status struct)
120        stores NULL in *st
121      */
122 
123     void preemphasis(
124         preemphasisState *st, /* (i/o): preemphasis filter state                */
125         Word16 *signal,    /* (i/o): input signal overwritten by the output     */
126         Word16 g,          /* (i)  : preemphasis coefficient                    */
127         Word16 L,          /* (i)  : size of filtering                          */
128         Flag   *pOverflow  /* (o)  : overflow indicator                         */
129     );
130 
131     /*----------------------------------------------------------------------------
132     ; END
133     ----------------------------------------------------------------------------*/
134 #ifdef __cplusplus
135 }
136 #endif
137 
138 #endif /* preemph_H_ */
139 
140 
141