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      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