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/src/include/pstfilt.h
35
36     Date: 02/05/2002
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             : pstfilt.h
51      Purpose          : Performs adaptive postfiltering on the synthesis
52                       : speech
53
54------------------------------------------------------------------------------
55*/
56
57#ifndef _PSTFILT_H_
58#define _PSTFILT_H_
59#define pstfilt_h "$Id $"
60
61/*----------------------------------------------------------------------------
62; INCLUDES
63----------------------------------------------------------------------------*/
64#include "typedef.h"
65#include "mode.h"
66#include "cnst.h"
67#include "preemph.h"
68#include "agc.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
86    /*----------------------------------------------------------------------------
87    ; EXTERNAL VARIABLES REFERENCES
88    ; [Declare variables used in this module but defined elsewhere]
89    ----------------------------------------------------------------------------*/
90
91    /*----------------------------------------------------------------------------
92    ; SIMPLE TYPEDEF'S
93    ----------------------------------------------------------------------------*/
94
95    /*----------------------------------------------------------------------------
96    ; ENUMERATED TYPEDEF'S
97    ----------------------------------------------------------------------------*/
98
99    /*----------------------------------------------------------------------------
100    ; STRUCTURES TYPEDEF'S
101    ----------------------------------------------------------------------------*/
102    typedef struct
103    {
104        Word16 res2[L_SUBFR];
105        Word16 mem_syn_pst[M];
106        preemphasisState preemph_state;
107        agcState agc_state;
108        Word16 synth_buf[M + L_FRAME];
109    } Post_FilterState;
110
111    /*----------------------------------------------------------------------------
112    ; GLOBAL FUNCTION DEFINITIONS
113    ; [List function prototypes here]
114    ----------------------------------------------------------------------------*/
115    Word16 Post_Filter_reset(Post_FilterState *st);
116    /* reset post filter (i.e. set state memory to zero)
117       returns 0 on success
118     */
119
120    void Post_Filter(
121        Post_FilterState *st, /* i/o : post filter states                        */
122        enum Mode mode,       /* i   : AMR mode                                  */
123        Word16 *syn,          /* i/o : synthesis speech (postfiltered is output) */
124        Word16 *Az_4,         /* i   : interpolated LPC parameters in all subfr. */
125        Flag   *pOverflow
126    );
127    /* filters the signal syn using the parameters in Az_4 to calculate filter
128       coefficients.
129       The filter must be set up using Post_Filter_init prior to the first call
130       to Post_Filter. Post_FilterState is updated to mirror the current state
131       of the filter
132
133       return 0 on success
134     */
135
136#ifdef __cplusplus
137}
138#endif
139
140#endif  /* _PSTFILT_H_ */
141
142
143
144