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1 
2 /* -----------------------------------------------------------------------------------------------------------
3 Software License for The Fraunhofer FDK AAC Codec Library for Android
4 
5 � Copyright  1995 - 2012 Fraunhofer-Gesellschaft zur F�rderung der angewandten Forschung e.V.
6   All rights reserved.
7 
8  1.    INTRODUCTION
9 The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
10 the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
11 This FDK AAC Codec software is intended to be used on a wide variety of Android devices.
12 
13 AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
14 audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
15 independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
16 of the MPEG specifications.
17 
18 Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
19 may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
20 individually for the purpose of encoding or decoding bit streams in products that are compliant with
21 the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
22 these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
23 software may already be covered under those patent licenses when it is used for those licensed purposes only.
24 
25 Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
26 are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
27 applications information and documentation.
28 
29 2.    COPYRIGHT LICENSE
30 
31 Redistribution and use in source and binary forms, with or without modification, are permitted without
32 payment of copyright license fees provided that you satisfy the following conditions:
33 
34 You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
35 your modifications thereto in source code form.
36 
37 You must retain the complete text of this software license in the documentation and/or other materials
38 provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
39 You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
40 modifications thereto to recipients of copies in binary form.
41 
42 The name of Fraunhofer may not be used to endorse or promote products derived from this library without
43 prior written permission.
44 
45 You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
46 software or your modifications thereto.
47 
48 Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
49 and the date of any change. For modified versions of the FDK AAC Codec, the term
50 "Fraunhofer FDK AAC Codec Library for Android" must be replaced by the term
51 "Third-Party Modified Version of the Fraunhofer FDK AAC Codec Library for Android."
52 
53 3.    NO PATENT LICENSE
54 
55 NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
56 ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
57 respect to this software.
58 
59 You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
60 by appropriate patent licenses.
61 
62 4.    DISCLAIMER
63 
64 This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors
65 "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, including but not limited to the implied warranties
66 of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
67 CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
68 including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
69 or business interruption, however caused and on any theory of liability, whether in contract, strict
70 liability, or tort (including negligence), arising in any way out of the use of this software, even if
71 advised of the possibility of such damage.
72 
73 5.    CONTACT INFORMATION
74 
75 Fraunhofer Institute for Integrated Circuits IIS
76 Attention: Audio and Multimedia Departments - FDK AAC LL
77 Am Wolfsmantel 33
78 91058 Erlangen, Germany
79 
80 www.iis.fraunhofer.de/amm
81 amm-info@iis.fraunhofer.de
82 ----------------------------------------------------------------------------------------------------------- */
83 
84 /*****************************  MPEG-4 AAC Decoder  **************************
85 
86    Author(s):   Josef Hoepfl
87    Description: individual channel stream info
88 
89 ******************************************************************************/
90 
91 #include "channelinfo.h"
92 #include "aac_rom.h"
93 #include "aac_ram.h"
94 #include "FDK_bitstream.h"
95 
96 
IcsReadMaxSfb(HANDLE_FDK_BITSTREAM bs,CIcsInfo * pIcsInfo,const SamplingRateInfo * pSamplingRateInfo)97 AAC_DECODER_ERROR IcsReadMaxSfb (
98         HANDLE_FDK_BITSTREAM bs,
99         CIcsInfo *pIcsInfo,
100         const SamplingRateInfo *pSamplingRateInfo
101         )
102 {
103   AAC_DECODER_ERROR ErrorStatus = AAC_DEC_OK;
104   int nbits;
105 
106   if (IsLongBlock(pIcsInfo)) {
107     nbits = 6;
108     pIcsInfo->TotalSfBands = pSamplingRateInfo->NumberOfScaleFactorBands_Long;
109   } else {
110     nbits = 4;
111     pIcsInfo->TotalSfBands = pSamplingRateInfo->NumberOfScaleFactorBands_Short;
112   }
113   pIcsInfo->MaxSfBands = (UCHAR) FDKreadBits(bs, nbits);
114 
115   if (pIcsInfo->MaxSfBands > pIcsInfo->TotalSfBands){
116     ErrorStatus = AAC_DEC_PARSE_ERROR;
117   }
118 
119   return ErrorStatus;
120 }
121 
122 
123 
IcsRead(HANDLE_FDK_BITSTREAM bs,CIcsInfo * pIcsInfo,const SamplingRateInfo * pSamplingRateInfo,const UINT flags)124 AAC_DECODER_ERROR IcsRead(HANDLE_FDK_BITSTREAM bs,
125                           CIcsInfo *pIcsInfo,
126                           const SamplingRateInfo* pSamplingRateInfo,
127                           const UINT flags)
128 {
129   AAC_DECODER_ERROR ErrorStatus = AAC_DEC_OK;
130 
131   pIcsInfo->Valid = 0;
132 
133   if (flags & AC_ELD){
134     pIcsInfo->WindowSequence = OnlyLongSequence;
135     pIcsInfo->WindowShape = 0;
136   }
137   else {
138     if ( !(flags & (AC_USAC|AC_RSVD50)) ) {
139       FDKreadBits(bs,1);
140     }
141     pIcsInfo->WindowSequence = (UCHAR) FDKreadBits(bs,2);
142     pIcsInfo->WindowShape = (UCHAR) FDKreadBits(bs,1);
143     if (flags & AC_LD) {
144       if (pIcsInfo->WindowShape) {
145         pIcsInfo->WindowShape = 2; /* select low overlap instead of KBD */
146       }
147     }
148   }
149 
150   /* Sanity check */
151   if ( (flags & (AC_ELD|AC_LD)) && pIcsInfo->WindowSequence != OnlyLongSequence) {
152     pIcsInfo->WindowSequence = OnlyLongSequence;
153     ErrorStatus = AAC_DEC_PARSE_ERROR;
154     goto bail;
155   }
156 
157   ErrorStatus = IcsReadMaxSfb(bs, pIcsInfo, pSamplingRateInfo);
158   if (ErrorStatus != AAC_DEC_OK) {
159     goto bail;
160   }
161 
162   if (IsLongBlock(pIcsInfo))
163   {
164     if ( !(flags & (AC_ELD|AC_SCALABLE|AC_BSAC|AC_USAC|AC_RSVD50)) ) /* If not ELD nor Scalable nor BSAC nor USAC syntax then ... */
165     {
166       if ((UCHAR)FDKreadBits(bs,1) != 0 ) /* UCHAR PredictorDataPresent */
167       {
168         ErrorStatus = AAC_DEC_UNSUPPORTED_PREDICTION;
169         goto bail;
170       }
171     }
172 
173     pIcsInfo->WindowGroups = 1;
174     pIcsInfo->WindowGroupLength[0] = 1;
175   }
176   else
177   {
178     INT i;
179     UINT mask;
180 
181     pIcsInfo->ScaleFactorGrouping = (UCHAR) FDKreadBits(bs,7);
182 
183     pIcsInfo->WindowGroups = 0 ;
184 
185     for (i=0; i < (8-1); i++)
186     {
187       mask = 1 << (6 - i);
188       pIcsInfo->WindowGroupLength[i] = 1;
189 
190       if (pIcsInfo->ScaleFactorGrouping & mask)
191       {
192         pIcsInfo->WindowGroupLength[pIcsInfo->WindowGroups]++;
193       }
194       else
195       {
196         pIcsInfo->WindowGroups++;
197       }
198     }
199 
200     /* loop runs to i < 7 only */
201     pIcsInfo->WindowGroupLength[8-1] = 1;
202     pIcsInfo->WindowGroups++;
203   }
204 
205 
206 bail:
207   if (ErrorStatus == AAC_DEC_OK)
208     pIcsInfo->Valid = 1;
209 
210   return ErrorStatus;
211 }
212 
213 
214 /*
215   interleave codebooks the following way
216 
217     9 (84w) |  1 (51w)
218    10 (82w) |  2 (39w)
219   SCL (65w) |  4 (38w)
220     3 (39w) |  5 (41w)
221             |  6 (40w)
222             |  7 (31w)
223             |  8 (31w)
224      (270w)     (271w)
225 */
226 
227 
228 /*
229   Table entries are sorted as following:
230   | num_swb_long_window | sfbands_long | num_swb_short_window | sfbands_short |
231 */
getSamplingRateInfo(SamplingRateInfo * t,UINT samplesPerFrame,UINT samplingRateIndex,UINT samplingRate)232 AAC_DECODER_ERROR getSamplingRateInfo(
233         SamplingRateInfo *t,
234         UINT samplesPerFrame,
235         UINT samplingRateIndex,
236         UINT samplingRate
237         )
238 {
239   int index = 0;
240 
241 
242   t->samplingRateIndex = samplingRateIndex;
243   t->samplingRate = samplingRate;
244 
245   switch (samplesPerFrame) {
246   case 1024:
247     index = 0;
248     break;
249   case 960:
250     index = 1;
251     break;
252   case 512:
253     index = 3;
254     break;
255   case 480:
256     index = 4;
257     break;
258 
259   default:
260     return AAC_DEC_UNSUPPORTED_FORMAT;
261   }
262 
263   t->ScaleFactorBands_Long = sfbOffsetTables[index][samplingRateIndex].sfbOffsetLong;
264   t->ScaleFactorBands_Short = sfbOffsetTables[index][samplingRateIndex].sfbOffsetShort;
265   t->NumberOfScaleFactorBands_Long = sfbOffsetTables[index][samplingRateIndex].numberOfSfbLong;
266   t->NumberOfScaleFactorBands_Short = sfbOffsetTables[index][samplingRateIndex].numberOfSfbShort;
267 
268   if (t->ScaleFactorBands_Long == NULL || t->NumberOfScaleFactorBands_Long == 0) {
269     return AAC_DEC_UNSUPPORTED_FORMAT;
270   }
271 
272   FDK_ASSERT(t->ScaleFactorBands_Long[t->NumberOfScaleFactorBands_Long] == samplesPerFrame);
273   FDK_ASSERT(t->ScaleFactorBands_Short == NULL || t->ScaleFactorBands_Short[t->NumberOfScaleFactorBands_Short]*8 == samplesPerFrame);
274 
275   return AAC_DEC_OK;
276 }
277