1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
|
/* ------------------------------------------------------------------
* Copyright (C) 1998-2009 PacketVideo
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
* express or implied.
* See the License for the specific language governing permissions
* and limitations under the License.
* -------------------------------------------------------------------
*/
/*
Pathname: ./src/set_mc_info.c
------------------------------------------------------------------------------
REVISION HISTORY
Description: Modified per review comments
Description: Change audioObjectType from Int to enum types
Who: Date:
Description:
------------------------------------------------------------------------------
INPUT AND OUTPUT DEFINITIONS
Inputs:
pMC_Info = pointer to structure MC_Info that holds information of
multiple channels' configurations
Data type pointer to MC_Info
objectType = variable that holds the Audio Object Type of current
file/bitstream.
Data type Int
sampling_rate_idx = variable that indicates the sampling rate of the
source file being encoded
Data Type Int
tag = variable that stores the element instance tag of the
first (front) channel element.
Data type Int
is_cpe = variable that indicates if a Channel Pair Element (CPE)
or a Single Channel Element (SCE) is used.
Data type Int (maybe Boolean)
pWinSeqInfo = array of pointers that points to structures holding
frame information of long and short window sequences.
Data type FrameInfo
pSfbwidth128 = array that will store the scalefactor bandwidth of
short window sequence frame.
Data type Int array
Local Stores/Buffers/Pointers Needed:
None
Global Stores/Buffers/Pointers Needed:
None
Outputs:
return SUCCESS
Pointers and Buffers Modified:
pMC_Info->nch contains the number of channels depending
upon if CPE or SCE is used
pMC_Info->objectType contents updated with the decoded Audio
Object Type
pMC_Info->ch_info.tag contents updated with the value of decoded
channel element tag
PMC_Info->ch_info.cpe contents updated depending upon if CPE or
SCE is used
pWinSeqInfo contents updated by calling infoinit if
sampling_rate_idx is different from
previous value
pSfbWidth128 contents updated by calling infoinit if
sampling_rate_idx is different from
previous value
Local Stores Modified:
None
Global Stores Modified:
None
------------------------------------------------------------------------------
FUNCTION DESCRIPTION
This function initializes the channel configuration information. The
structure MC_Info stores the number of channels, channel element tag.
If sampling rate index is different from the previous value,
The frame information will be updated by calling infoinit.c
------------------------------------------------------------------------------
REQUIREMENTS
This function shall update the relevant information on channel configs
------------------------------------------------------------------------------
REFERENCES
(1) MPEG-2 NBC Audio Decoder
"This software module was originally developed by AT&T, Dolby
Laboratories, Fraunhofer Gesellschaft IIS in the course of development
of the MPEG-2 NBC/MPEG-4 Audio standard ISO/IEC 13818-7, 14496-1,2 and
3. This software module is an implementation of a part of one or more
MPEG-2 NBC/MPEG-4 Audio tools as specified by the MPEG-2 NBC/MPEG-4
Audio standard. ISO/IEC gives users of the MPEG-2 NBC/MPEG-4 Audio
standards free license to this software module or modifications thereof
for use in hardware or software products claiming conformance to the
MPEG-2 NBC/MPEG-4 Audio standards. Those intending to use this software
module in hardware or software products are advised that this use may
infringe existing patents. The original developer of this software
module and his/her company, the subsequent editors and their companies,
and ISO/IEC have no liability for use of this software module or
modifications thereof in an implementation. Copyright is not released
for non MPEG-2 NBC/MPEG-4 Audio conforming products.The original
developer retains full right to use the code for his/her own purpose,
assign or donate the code to a third party and to inhibit third party
from using the code for non MPEG-2 NBC/MPEG-4 Audio conforming products.
This copyright notice must be included in all copies or derivative
works."
Copyright(c)1996.
(2) ISO/IEC 14496-3: 1999(E)
Subpart 1 p20 Table 1.6.3
Subpart 4 p30 5.1.2.1
Subpart 4 p31 4.5.2.1.1
------------------------------------------------------------------------------
PSEUDO-CODE
pMC_Info->nch = 0;
pMC_Info->profile = objectType;
IF (pMC_Info->sampling_rate_idx != sampling_rate_idx)
THEN
pMC_Info->sampling_rate_idx = sampling_rate_idx;
CALL infoinit(
samp_rate_idx = sampling_rate_idx
ppWin_seq_info= pWinSeqInfo
pSfbwidth128 = pSfbwidth128)
MODIFYING(pWinSeqInfo, pSfbwidth128)
RETURNING(None)
ENDIF
pCh_Info = &pMC_Info->ch_info[0];
pCh_Info->tag = tag;
IF (is_cpe == FALSE)
THEN
pCh_Info->cpe = FALSE;
pMC_Info->nch = 1;
ELSE
pCh_Info->cpe = TRUE;
pCh_Info = &pMC_Info->ch_info[1];
pCh_Info->tag = tag;
pCh_Info->cpe = TRUE;
pMC_Info->nch = 2;
ENDIF
RETURN(SUCCESS)
------------------------------------------------------------------------------
RESOURCES USED
When the code is written for a specific target processor the
the resources used should be documented below.
STACK USAGE: [stack count for this module] + [variable to represent
stack usage for each subroutine called]
where: [stack usage variable] = stack usage for [subroutine
name] (see [filename].ext)
DATA MEMORY USED: x words
PROGRAM MEMORY USED: x words
CLOCK CYCLES: [cycle count equation for this module] + [variable
used to represent cycle count for each subroutine
called]
where: [cycle count variable] = cycle count for [subroutine
name] (see [filename].ext)
------------------------------------------------------------------------------
*/
/*----------------------------------------------------------------------------
; INCLUDES
----------------------------------------------------------------------------*/
#include "pv_audio_type_defs.h"
#include "set_mc_info.h"
#include "huffman.h"
#include "s_ch_info.h"
/*----------------------------------------------------------------------------
; MACROS
; Define module specific macros here
----------------------------------------------------------------------------*/
/*----------------------------------------------------------------------------
; DEFINES
; Include all pre-processor statements here. Include conditional
; compile variables also.
----------------------------------------------------------------------------*/
/*----------------------------------------------------------------------------
; LOCAL FUNCTION DEFINITIONS
; Function Prototype declaration
----------------------------------------------------------------------------*/
/*----------------------------------------------------------------------------
; LOCAL STORE/BUFFER/POINTER DEFINITIONS
; Variable declaration - defined here and used outside this module
----------------------------------------------------------------------------*/
/*----------------------------------------------------------------------------
; EXTERNAL FUNCTION REFERENCES
; Declare functions defined elsewhere and referenced in this module
----------------------------------------------------------------------------*/
/*----------------------------------------------------------------------------
; EXTERNAL GLOBAL STORE/BUFFER/POINTER REFERENCES
; Declare variables used in this module but defined elsewhere
----------------------------------------------------------------------------*/
/*----------------------------------------------------------------------------
; FUNCTION CODE
----------------------------------------------------------------------------*/
Int set_mc_info(
MC_Info *pMC_Info,
const tMP4AudioObjectType audioObjectType, /* used to be profile */
const Int sampling_rate_idx,
const Int tag, /* always pass-in last element's value */
const Int is_cpe,
FrameInfo *pWinSeqInfo[],
Int sfbwidth128[]
)
{
Ch_Info *pCh_Info; /*optional task: eliminate this structure */
/*
* audioObjectType and sampling rate
* re-configure if new sampling rate
*
*/
pMC_Info->audioObjectType = audioObjectType;
if (pMC_Info->sampling_rate_idx != sampling_rate_idx)
{
pMC_Info->sampling_rate_idx = sampling_rate_idx;
Int status;
status = infoinit(sampling_rate_idx,
pWinSeqInfo,
sfbwidth128);
if (SUCCESS != status)
{
return 1;
}
}
/*
* first setup values for mono config, Single Channel Element (SCE)
* then if stereo, go inside if(is_cpe != FALSE) branch to setup
* values for stereo.
* set the channel counts
* save tag for left channel
*/
pMC_Info->nch = 1 + is_cpe;
pCh_Info = &pMC_Info->ch_info[0];
pCh_Info->tag = tag;
pCh_Info->cpe = is_cpe;
/* This if branch maybe deleted in the future */
if (is_cpe != FALSE)
{
/* Channel Pair Element (CPE) */
/* right channel*/
pCh_Info = &pMC_Info->ch_info[1];
pCh_Info->cpe = TRUE;
}
return(SUCCESS); /* possible future error checkings */
}
|
