1 /* -----------------------------------------------------------------------------
2 Software License for The Fraunhofer FDK AAC Codec Library for Android
3
4 © Copyright 1995 - 2018 Fraunhofer-Gesellschaft zur Förderung der angewandten
5 Forschung e.V. All rights reserved.
6
7 1. INTRODUCTION
8 The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software
9 that implements the MPEG Advanced Audio Coding ("AAC") encoding and decoding
10 scheme for digital audio. This FDK AAC Codec software is intended to be used on
11 a wide variety of Android devices.
12
13 AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient
14 general perceptual audio codecs. AAC-ELD is considered the best-performing
15 full-bandwidth communications codec by independent studies and is widely
16 deployed. AAC has been standardized by ISO and IEC as part of the MPEG
17 specifications.
18
19 Patent licenses for necessary patent claims for the FDK AAC Codec (including
20 those of Fraunhofer) may be obtained through Via Licensing
21 (www.vialicensing.com) or through the respective patent owners individually for
22 the purpose of encoding or decoding bit streams in products that are compliant
23 with the ISO/IEC MPEG audio standards. Please note that most manufacturers of
24 Android devices already license these patent claims through Via Licensing or
25 directly from the patent owners, and therefore FDK AAC Codec software may
26 already be covered under those patent licenses when it is used for those
27 licensed purposes only.
28
29 Commercially-licensed AAC software libraries, including floating-point versions
30 with enhanced sound quality, are also available from Fraunhofer. Users are
31 encouraged to check the Fraunhofer website for additional applications
32 information and documentation.
33
34 2. COPYRIGHT LICENSE
35
36 Redistribution and use in source and binary forms, with or without modification,
37 are permitted without payment of copyright license fees provided that you
38 satisfy the following conditions:
39
40 You must retain the complete text of this software license in redistributions of
41 the FDK AAC Codec or your modifications thereto in source code form.
42
43 You must retain the complete text of this software license in the documentation
44 and/or other materials provided with redistributions of the FDK AAC Codec or
45 your modifications thereto in binary form. You must make available free of
46 charge copies of the complete source code of the FDK AAC Codec and your
47 modifications thereto to recipients of copies in binary form.
48
49 The name of Fraunhofer may not be used to endorse or promote products derived
50 from this library without prior written permission.
51
52 You may not charge copyright license fees for anyone to use, copy or distribute
53 the FDK AAC Codec software or your modifications thereto.
54
55 Your modified versions of the FDK AAC Codec must carry prominent notices stating
56 that you changed the software and the date of any change. For modified versions
57 of the FDK AAC Codec, the term "Fraunhofer FDK AAC Codec Library for Android"
58 must be replaced by the term "Third-Party Modified Version of the Fraunhofer FDK
59 AAC Codec Library for Android."
60
61 3. NO PATENT LICENSE
62
63 NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without
64 limitation the patents of Fraunhofer, ARE GRANTED BY THIS SOFTWARE LICENSE.
65 Fraunhofer provides no warranty of patent non-infringement with respect to this
66 software.
67
68 You may use this FDK AAC Codec software or modifications thereto only for
69 purposes that are authorized by appropriate patent licenses.
70
71 4. DISCLAIMER
72
73 This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright
74 holders and contributors "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES,
75 including but not limited to the implied warranties of merchantability and
76 fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
77 CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary,
78 or consequential damages, including but not limited to procurement of substitute
79 goods or services; loss of use, data, or profits, or business interruption,
80 however caused and on any theory of liability, whether in contract, strict
81 liability, or tort (including negligence), arising in any way out of the use of
82 this software, even if advised of the possibility of such damage.
83
84 5. CONTACT INFORMATION
85
86 Fraunhofer Institute for Integrated Circuits IIS
87 Attention: Audio and Multimedia Departments - FDK AAC LL
88 Am Wolfsmantel 33
89 91058 Erlangen, Germany
90
91 www.iis.fraunhofer.de/amm
92 amm-info@iis.fraunhofer.de
93 ----------------------------------------------------------------------------- */
94
95 /**************************** AAC decoder library ******************************
96
97 Author(s): Josef Hoepfl
98
99 Description: individual channel stream info
100
101 *******************************************************************************/
102
103 #include "channelinfo.h"
104 #include "aac_rom.h"
105 #include "aac_ram.h"
106 #include "FDK_bitstream.h"
107
IcsReadMaxSfb(HANDLE_FDK_BITSTREAM bs,CIcsInfo * pIcsInfo,const SamplingRateInfo * pSamplingRateInfo)108 AAC_DECODER_ERROR IcsReadMaxSfb(HANDLE_FDK_BITSTREAM bs, CIcsInfo *pIcsInfo,
109 const SamplingRateInfo *pSamplingRateInfo) {
110 AAC_DECODER_ERROR ErrorStatus = AAC_DEC_OK;
111 int nbits;
112
113 if (IsLongBlock(pIcsInfo)) {
114 nbits = 6;
115 pIcsInfo->TotalSfBands = pSamplingRateInfo->NumberOfScaleFactorBands_Long;
116 } else {
117 nbits = 4;
118 pIcsInfo->TotalSfBands = pSamplingRateInfo->NumberOfScaleFactorBands_Short;
119 }
120 pIcsInfo->MaxSfBands = (UCHAR)FDKreadBits(bs, nbits);
121
122 if (pIcsInfo->MaxSfBands > pIcsInfo->TotalSfBands) {
123 ErrorStatus = AAC_DEC_PARSE_ERROR;
124 }
125
126 return ErrorStatus;
127 }
128
IcsRead(HANDLE_FDK_BITSTREAM bs,CIcsInfo * pIcsInfo,const SamplingRateInfo * pSamplingRateInfo,const UINT flags)129 AAC_DECODER_ERROR IcsRead(HANDLE_FDK_BITSTREAM bs, CIcsInfo *pIcsInfo,
130 const SamplingRateInfo *pSamplingRateInfo,
131 const UINT flags) {
132 AAC_DECODER_ERROR ErrorStatus = AAC_DEC_OK;
133
134 pIcsInfo->Valid = 0;
135
136 if (flags & AC_ELD) {
137 pIcsInfo->WindowSequence = BLOCK_LONG;
138 pIcsInfo->WindowShape = 0;
139 } else {
140 if (!(flags & (AC_USAC | AC_RSVD50 | AC_RSV603DA))) {
141 FDKreadBits(bs, 1);
142 }
143 pIcsInfo->WindowSequence = (BLOCK_TYPE)FDKreadBits(bs, 2);
144 pIcsInfo->WindowShape = (UCHAR)FDKreadBits(bs, 1);
145 if (flags & AC_LD) {
146 if (pIcsInfo->WindowShape) {
147 pIcsInfo->WindowShape = 2; /* select low overlap instead of KBD */
148 }
149 }
150 }
151
152 /* Sanity check */
153 if ((flags & (AC_ELD | AC_LD)) && pIcsInfo->WindowSequence != BLOCK_LONG) {
154 pIcsInfo->WindowSequence = BLOCK_LONG;
155 ErrorStatus = AAC_DEC_PARSE_ERROR;
156 goto bail;
157 }
158
159 ErrorStatus = IcsReadMaxSfb(bs, pIcsInfo, pSamplingRateInfo);
160 if (ErrorStatus != AAC_DEC_OK) {
161 goto bail;
162 }
163
164 if (IsLongBlock(pIcsInfo)) {
165 if (!(flags & (AC_ELD | AC_SCALABLE | AC_BSAC | AC_USAC | AC_RSVD50 |
166 AC_RSV603DA))) /* If not ELD nor Scalable nor BSAC nor USAC
167 syntax then ... */
168 {
169 if ((UCHAR)FDKreadBits(bs, 1) != 0) /* UCHAR PredictorDataPresent */
170 {
171 ErrorStatus = AAC_DEC_UNSUPPORTED_PREDICTION;
172 goto bail;
173 }
174 }
175
176 pIcsInfo->WindowGroups = 1;
177 pIcsInfo->WindowGroupLength[0] = 1;
178 } else {
179 INT i;
180 UINT mask;
181
182 pIcsInfo->ScaleFactorGrouping = (UCHAR)FDKreadBits(bs, 7);
183
184 pIcsInfo->WindowGroups = 0;
185
186 for (i = 0; i < (8 - 1); i++) {
187 mask = 1 << (6 - i);
188 pIcsInfo->WindowGroupLength[i] = 1;
189
190 if (pIcsInfo->ScaleFactorGrouping & mask) {
191 pIcsInfo->WindowGroupLength[pIcsInfo->WindowGroups]++;
192 } else {
193 pIcsInfo->WindowGroups++;
194 }
195 }
196
197 /* loop runs to i < 7 only */
198 pIcsInfo->WindowGroupLength[8 - 1] = 1;
199 pIcsInfo->WindowGroups++;
200 }
201
202 bail:
203 if (ErrorStatus == AAC_DEC_OK) pIcsInfo->Valid = 1;
204
205 return ErrorStatus;
206 }
207
208 /*
209 interleave codebooks the following way
210
211 9 (84w) | 1 (51w)
212 10 (82w) | 2 (39w)
213 SCL (65w) | 4 (38w)
214 3 (39w) | 5 (41w)
215 | 6 (40w)
216 | 7 (31w)
217 | 8 (31w)
218 (270w) (271w)
219 */
220
221 /*
222 Table entries are sorted as following:
223 | num_swb_long_window | sfbands_long | num_swb_short_window | sfbands_short |
224 */
getSamplingRateInfo(SamplingRateInfo * t,UINT samplesPerFrame,UINT samplingRateIndex,UINT samplingRate)225 AAC_DECODER_ERROR getSamplingRateInfo(SamplingRateInfo *t, UINT samplesPerFrame,
226 UINT samplingRateIndex,
227 UINT samplingRate) {
228 int index = 0;
229
230 /* Search closest samplerate according to ISO/IEC 13818-7:2005(E) 8.2.4 (Table
231 * 38): */
232 if ((samplingRateIndex >= 15) || (samplesPerFrame == 768)) {
233 const UINT borders[] = {(UINT)-1, 92017, 75132, 55426, 46009, 37566,
234 27713, 23004, 18783, 13856, 11502, 9391};
235 UINT i, samplingRateSearch = samplingRate;
236
237 if (samplesPerFrame == 768) {
238 samplingRateSearch = (samplingRate * 4) / 3;
239 }
240
241 for (i = 0; i < 11; i++) {
242 if (borders[i] > samplingRateSearch &&
243 samplingRateSearch >= borders[i + 1]) {
244 break;
245 }
246 }
247 samplingRateIndex = i;
248 }
249
250 t->samplingRateIndex = samplingRateIndex;
251 t->samplingRate = samplingRate;
252
253 switch (samplesPerFrame) {
254 case 1024:
255 index = 0;
256 break;
257 case 960:
258 index = 1;
259 break;
260 case 768:
261 index = 2;
262 break;
263 case 512:
264 index = 3;
265 break;
266 case 480:
267 index = 4;
268 break;
269
270 default:
271 return AAC_DEC_UNSUPPORTED_FORMAT;
272 }
273
274 t->ScaleFactorBands_Long =
275 sfbOffsetTables[index][samplingRateIndex].sfbOffsetLong;
276 t->ScaleFactorBands_Short =
277 sfbOffsetTables[index][samplingRateIndex].sfbOffsetShort;
278 t->NumberOfScaleFactorBands_Long =
279 sfbOffsetTables[index][samplingRateIndex].numberOfSfbLong;
280 t->NumberOfScaleFactorBands_Short =
281 sfbOffsetTables[index][samplingRateIndex].numberOfSfbShort;
282
283 if (t->ScaleFactorBands_Long == NULL ||
284 t->NumberOfScaleFactorBands_Long == 0) {
285 t->samplingRate = 0;
286 return AAC_DEC_UNSUPPORTED_FORMAT;
287 }
288
289 FDK_ASSERT((UINT)t->ScaleFactorBands_Long[t->NumberOfScaleFactorBands_Long] ==
290 samplesPerFrame);
291 FDK_ASSERT(
292 t->ScaleFactorBands_Short == NULL ||
293 (UINT)t->ScaleFactorBands_Short[t->NumberOfScaleFactorBands_Short] * 8 ==
294 samplesPerFrame);
295
296 return AAC_DEC_OK;
297 }
298