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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  Pathname: ./audio/gsm-amr/c/src/if2_to_ets.c
33  Funtions: if2_to_ets
34 
35 */
36 
37 /*----------------------------------------------------------------------------
38 ; INCLUDES
39 ----------------------------------------------------------------------------*/
40 #include "frame_type_3gpp.h"
41 #include "if2_to_ets.h"
42 #include "typedef.h"
43 #include "bitreorder_tab.h"
44 /*----------------------------------------------------------------------------
45 ; MACROS
46 ; Define module specific macros here
47 ----------------------------------------------------------------------------*/
48 
49 /*----------------------------------------------------------------------------
50 ; DEFINES
51 ; Include all pre-processor statements here. Include conditional
52 ; compile variables also.
53 ----------------------------------------------------------------------------*/
54 
55 
56 /*----------------------------------------------------------------------------
57 ; LOCAL FUNCTION DEFINITIONS
58 ; Function Prototype declaration
59 ----------------------------------------------------------------------------*/
60 
61 /*----------------------------------------------------------------------------
62 ; LOCAL VARIABLE DEFINITIONS
63 ; Variable declaration - defined here and used outside this module
64 ----------------------------------------------------------------------------*/
65 
66 
67 
68 /*
69 ------------------------------------------------------------------------------
70  FUNCTION NAME: if2_to_ets
71 ------------------------------------------------------------------------------
72  INPUT AND OUTPUT DEFINITIONS
73 
74  Inputs:
75     frame_type_3gpp = decoder speech bit rate (enum Frame_Type_3GPP)
76     if2_input_ptr   = pointer to input encoded speech bits in IF2 format (Word8)
77     ets_output_ptr  = pointer to output encoded speech bits in ETS format (Word16)
78 
79  Outputs:
80     ets_output_ptr  = pointer to encoded speech bits in the ETS format (Word16)
81 
82  Returns:
83     None
84 
85  Global Variables Used:
86     None
87 
88  Local Variables Needed:
89     None
90 
91 ------------------------------------------------------------------------------
92  FUNCTION DESCRIPTION
93 
94  This function performs a transformation on the data buffers. It converts the
95  data format from IF2 to ETS. IF2 is the storage format where the frame type
96  is in the first four bits of the first byte. The upper four bits of that byte
97  contain the first four encoded speech bits for the frame. The following bytes
98  contain the rest of the encoded speech bits. The final byte has padded zeros
99  to make the frame byte aligned. ETS format has the encoded speech
100  bits each separate with only one bit stored in each word.
101 
102 ------------------------------------------------------------------------------
103  REQUIREMENTS
104 
105  None
106 
107 ------------------------------------------------------------------------------
108  REFERENCES
109 
110 AMR Speech Codec Frame Structure", 3GPP TS 26.101 version 4.1.0 Release 4, June 2001
111 
112 ------------------------------------------------------------------------------
113  PSEUDO-CODE
114 
115 
116 
117 ------------------------------------------------------------------------------
118  RESOURCES USED [optional]
119 
120  When the code is written for a specific target processor the
121  the resources used should be documented below.
122 
123  HEAP MEMORY USED: x bytes
124 
125  STACK MEMORY USED: x bytes
126 
127  CLOCK CYCLES: (cycle count equation for this function) + (variable
128                 used to represent cycle count for each subroutine
129                 called)
130      where: (cycle count variable) = cycle count for [subroutine
131                                      name]
132 
133 ------------------------------------------------------------------------------
134  CAUTION [optional]
135  [State any special notes, constraints or cautions for users of this function]
136 
137 ------------------------------------------------------------------------------
138 */
139 
if2_to_ets(enum Frame_Type_3GPP frame_type_3gpp,UWord8 * if2_input_ptr,Word16 * ets_output_ptr)140 void if2_to_ets(
141     enum Frame_Type_3GPP frame_type_3gpp,
142     UWord8   *if2_input_ptr,
143     Word16   *ets_output_ptr)
144 {
145 
146     Word16 i;
147     Word16 j;
148     Word16 x = 0;
149 
150     /*
151      * The following section of code accesses bits in the IF2 method of
152      * bit ordering. Each bit is given its own location in the buffer pointed
153      * to by ets_output_ptr. The bits (for modes less than AMR_SID) are
154      * reordered using the tables in bitreorder.c before the data is stored
155      * into the buffer pointed to by ets_output_ptr.
156      */
157 
158     if (frame_type_3gpp < AMR_SID)
159     {
160         for (j = 4; j < 8; j++)
161         {
162             ets_output_ptr[reorderBits[frame_type_3gpp][x++]] =
163                 (if2_input_ptr[0] >> j) & 0x01;
164         }
165         for (i = 1; i < numCompressedBytes[frame_type_3gpp]; i++)
166         {
167             for (j = 0; j < 8; j++)
168             {
169                 if (x >= numOfBits[frame_type_3gpp])
170                 {
171                     break;
172                 }
173                 ets_output_ptr[reorderBits[frame_type_3gpp][x++]] =
174                     (if2_input_ptr[i] >> j) & 0x01;
175             }
176         }
177     }
178     else
179     {
180         for (j = 4; j < 8; j++)
181         {
182             ets_output_ptr[x++] =
183                 (if2_input_ptr[0] >> j) & 0x01;
184         }
185         for (i = 1; i < numCompressedBytes[frame_type_3gpp]; i++)
186         {
187             for (j = 0; j < 8; j++)
188             {
189                 ets_output_ptr[x++] =
190                     (if2_input_ptr[i] >> j) & 0x01;
191             }
192         }
193     }
194 
195     return;
196 }
197