1
2/* -----------------------------------------------------------------------------------------------------------
3Software License for The Fraunhofer FDK AAC Codec Library for Android
4
5� Copyright  1995 - 2013 Fraunhofer-Gesellschaft zur F�rderung der angewandten Forschung e.V.
6  All rights reserved.
7
8 1.    INTRODUCTION
9The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
10the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
11This FDK AAC Codec software is intended to be used on a wide variety of Android devices.
12
13AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
14audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
15independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
16of the MPEG specifications.
17
18Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
19may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
20individually for the purpose of encoding or decoding bit streams in products that are compliant with
21the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
22these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
23software may already be covered under those patent licenses when it is used for those licensed purposes only.
24
25Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
26are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
27applications information and documentation.
28
292.    COPYRIGHT LICENSE
30
31Redistribution and use in source and binary forms, with or without modification, are permitted without
32payment of copyright license fees provided that you satisfy the following conditions:
33
34You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
35your modifications thereto in source code form.
36
37You must retain the complete text of this software license in the documentation and/or other materials
38provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
39You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
40modifications thereto to recipients of copies in binary form.
41
42The name of Fraunhofer may not be used to endorse or promote products derived from this library without
43prior written permission.
44
45You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
46software or your modifications thereto.
47
48Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
49and 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
533.    NO PATENT LICENSE
54
55NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
56ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
57respect to this software.
58
59You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
60by appropriate patent licenses.
61
624.    DISCLAIMER
63
64This 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
66of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
67CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
68including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
69or business interruption, however caused and on any theory of liability, whether in contract, strict
70liability, or tort (including negligence), arising in any way out of the use of this software, even if
71advised of the possibility of such damage.
72
735.    CONTACT INFORMATION
74
75Fraunhofer Institute for Integrated Circuits IIS
76Attention: Audio and Multimedia Departments - FDK AAC LL
77Am Wolfsmantel 33
7891058 Erlangen, Germany
79
80www.iis.fraunhofer.de/amm
81amm-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
97AAC_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
124AAC_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
206bail:
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*/
232AAC_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