1 /* ------------------------------------------------------------------
2 * Copyright (C) 1998-2009 PacketVideo
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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
14 * See the License for the specific language governing permissions
15 * and limitations under the License.
16 * -------------------------------------------------------------------
18 /****************************************************************************************
19 Portions of this file are derived from the following 3GPP standard:
22 ANSI-C code for the Adaptive Multi-Rate - Wideband (AMR-WB) speech codec
23 Available from http://www.3gpp.org
25 (C) 2007, 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 ****************************************************************************************/
30 ------------------------------------------------------------------------------
34 Filename: normalize_amr_wb.cpp
36 ------------------------------------------------------------------------------
37 INPUT AND OUTPUT DEFINITIONS
40 Int32 x 32-bit integer non-zero input
42 Int16 i number of leading zeros on x
45 ------------------------------------------------------------------------------
48 Returns number of leading zeros on the non-zero input
50 ------------------------------------------------------------------------------
54 ------------------------------------------------------------------------------
57 ------------------------------------------------------------------------------
60 ------------------------------------------------------------------------------
64 /*----------------------------------------------------------------------------
66 ----------------------------------------------------------------------------*/
68 #include "pv_amr_wb_type_defs.h"
69 #include "normalize_amr_wb.h"
71 /*----------------------------------------------------------------------------
73 ; Define module specific macros here
74 ----------------------------------------------------------------------------*/
77 /*----------------------------------------------------------------------------
79 ; Include all pre-processor statements here. Include conditional
80 ; compile variables also.
81 ----------------------------------------------------------------------------*/
83 /*----------------------------------------------------------------------------
84 ; LOCAL FUNCTION DEFINITIONS
85 ; Function Prototype declaration
86 ----------------------------------------------------------------------------*/
88 /*----------------------------------------------------------------------------
89 ; LOCAL STORE/BUFFER/POINTER DEFINITIONS
90 ; Variable declaration - defined here and used outside this module
91 ----------------------------------------------------------------------------*/
93 /*----------------------------------------------------------------------------
94 ; EXTERNAL FUNCTION REFERENCES
95 ; Declare functions defined elsewhere and referenced in this module
96 ----------------------------------------------------------------------------*/
98 /*----------------------------------------------------------------------------
99 ; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES
100 ; Declare variables used in this module but defined elsewhere
101 ----------------------------------------------------------------------------*/
103 /*----------------------------------------------------------------------------
105 ----------------------------------------------------------------------------*/
107 #if defined(PV_ARM_V5)
108 #elif defined(PV_ARM_GCC_V5)
110 /* function is inlined in header file */
115 int16 normalize_amr_wb(int32 x)
117 /*----------------------------------------------------------------------------
118 ; Define all local variables
119 ----------------------------------------------------------------------------*/
125 i = 0; /* most likely case */
127 else if (x > 0x00FFFFFF)
129 i = 3; /* second most likely case */
131 else if (x > 0x0000FFFF)
133 i = x > 0x000FFFFF ? 7 : 11;
139 i = x > 0x00000FFF ? 15 : 19;
143 i = x > 0x0000000F ? 23 : 27;
150 switch (x & 0x78000000)