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 Filename: /audio/gsm_amr/c/include/log2_norm.h
32
33------------------------------------------------------------------------------
34 REVISION HISTORY
35
36 Description: Created separate header file for Log2_norm function.
37
38 Description: Updated function prototype declaration to reflect new interface.
39              A pointer to overflow flag is passed into the function. Updated
40              template. Added extern declaration for log2_tbl[]
41
42 Description: Moved _cplusplus #ifdef after Include section.
43
44 Who:                       Date:
45 Description:
46
47------------------------------------------------------------------------------
48 INCLUDE DESCRIPTION
49
50 This file contains the prototype declaration for Log2_norm function.
51
52------------------------------------------------------------------------------
53*/
54
55/*----------------------------------------------------------------------------
56; CONTINUE ONLY IF NOT ALREADY DEFINED
57----------------------------------------------------------------------------*/
58#ifndef LOG2_NORM_H
59#define LOG2_NORM_H
60
61#define log2_h "$Id $"              /* Used by legacy code */
62
63/*----------------------------------------------------------------------------
64; INCLUDES
65----------------------------------------------------------------------------*/
66#include    "typedef.h"
67
68/*--------------------------------------------------------------------------*/
69#ifdef __cplusplus
70extern "C"
71{
72#endif
73
74    /*----------------------------------------------------------------------------
75    ; MACROS
76    ; Define module specific macros here
77    ----------------------------------------------------------------------------*/
78
79    /*----------------------------------------------------------------------------
80    ; DEFINES
81    ; Include all pre-processor statements here.
82    ----------------------------------------------------------------------------*/
83
84    /*----------------------------------------------------------------------------
85    ; EXTERNAL VARIABLES REFERENCES
86    ; Declare variables used in this module but defined elsewhere
87    ----------------------------------------------------------------------------*/
88    extern const Word16 log2_tbl[];
89    /*----------------------------------------------------------------------------
90    ; SIMPLE TYPEDEF'S
91    ----------------------------------------------------------------------------*/
92
93    /*----------------------------------------------------------------------------
94    ; ENUMERATED TYPEDEF'S
95    ----------------------------------------------------------------------------*/
96
97    /*----------------------------------------------------------------------------
98    ; STRUCTURES TYPEDEF'S
99    ----------------------------------------------------------------------------*/
100
101    /*----------------------------------------------------------------------------
102    ; GLOBAL FUNCTION DEFINITIONS
103    ; Function Prototype declaration
104    ----------------------------------------------------------------------------*/
105    void Log2_norm(
106        Word32 L_x,        /* (i) : input value (normalized)                    */
107        Word16 exp,        /* (i) : norm_l (L_x)                                */
108        Word16 *exponent,  /* (o) : Integer part of Log2.   (range: 0<=val<=30) */
109        Word16 *fraction   /* (o) : Fractional part of Log2. (range: 0<=val<1)  */
110    );
111
112    /*----------------------------------------------------------------------------
113    ; END
114    ----------------------------------------------------------------------------*/
115#ifdef __cplusplus
116}
117#endif
118
119#endif /* _LOG2_NORM_H_ */
120