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: long/short-block decoding
88
89 ******************************************************************************/
90
91 #ifndef BLOCK_H
92 #define BLOCK_H
93
94 #include "common_fix.h"
95
96 #include "channelinfo.h"
97 #include "FDK_bitstream.h"
98
99 /* PNS (of block) */
100 void CPns_Read (CPnsData *pPnsData,
101 HANDLE_FDK_BITSTREAM bs,
102 const CodeBookDescription *hcb,
103 SHORT *pScaleFactor,
104 UCHAR global_gain,
105 int band,
106 int group);
107
108
109 void CPns_Apply (const CPnsData *pPnsData,
110 const CIcsInfo *pIcsInfo,
111 SPECTRAL_PTR pSpectrum,
112 const SHORT *pSpecScale,
113 const SHORT *pScaleFactor,
114 const SamplingRateInfo *pSamplingRateInfo,
115 const INT granuleLength,
116 const int channel);
117
118
119
120 /* TNS (of block) */
121 /*!
122 \brief Read tns data-present flag from bitstream
123
124 The function reads the data-present flag for tns from
125 the bitstream.
126
127 \return none
128 */
129 void CTns_ReadDataPresentFlag(HANDLE_FDK_BITSTREAM bs,
130 CTnsData *pTnsData);
131
132 void CTns_ReadDataPresentUsac(
133 HANDLE_FDK_BITSTREAM hBs,
134 CTnsData *pTnsData0,
135 CTnsData *pTnsData1,
136 const CIcsInfo *pIcsInfo,
137 const UINT flags,
138 const int fCommonWindow
139 );
140
141 AAC_DECODER_ERROR CTns_Read(HANDLE_FDK_BITSTREAM bs,
142 CTnsData *pTnsData,
143 const CIcsInfo *pIcsInfo,
144 const UINT flags);
145
146 void CTns_Apply ( CTnsData *RESTRICT pTnsData, /*!< pointer to aac decoder info */
147 const CIcsInfo *pIcsInfo,
148 SPECTRAL_PTR pSpectralCoefficient,
149 const SamplingRateInfo *pSamplingRateInfo,
150 const INT granuleLength);
151
152 /* Block */
153
154 LONG CBlock_GetEscape(HANDLE_FDK_BITSTREAM bs, const LONG q);
155
156 /**
157 * \brief Read scale factor data. See chapter 4.6.2.3.2 of ISO/IEC 14496-3.
158 * The SF_OFFSET = 100 value referenced in chapter 4.6.2.3.3 is already substracted
159 * from the scale factor values. Also includes PNS data reading.
160 * \param bs bit stream handle data source
161 * \param pAacDecoderChannelInfo channel context info were decoded data is stored into.
162 * \param flags the decoder flags.
163 */
164 AAC_DECODER_ERROR CBlock_ReadScaleFactorData(
165 CAacDecoderChannelInfo *pAacDecoderChannelInfo,
166 HANDLE_FDK_BITSTREAM bs,
167 const UINT flags
168 );
169
170 /**
171 * \brief Read Huffman encoded spectral data.
172 * \param pAacDecoderChannelInfo channel context info.
173 * \param pSamplingRateInfo sampling rate info (sfb offsets).
174 * \param flags syntax flags.
175 */
176 AAC_DECODER_ERROR CBlock_ReadSpectralData(HANDLE_FDK_BITSTREAM bs,
177 CAacDecoderChannelInfo *pAacDecoderChannelInfo,
178 const SamplingRateInfo *pSamplingRateInfo,
179 const UINT flags);
180
181
182 AAC_DECODER_ERROR CBlock_ReadSectionData(HANDLE_FDK_BITSTREAM bs,
183 CAacDecoderChannelInfo *pAacDecoderChannelInfo,
184 const SamplingRateInfo *pSamplingRateInfo,
185 const UINT flags);
186
187 /**
188 * \brief find a common exponent (shift factor) for all sfb in each Spectral window, and store them into
189 * CAacDecoderChannelInfo::specScale.
190 * \param pAacDecoderChannelInfo channel context info.
191 * \param pSamplingRateInfo sampling rate info (sfb offsets).
192 */
193 void CBlock_ScaleSpectralData(CAacDecoderChannelInfo *pAacDecoderChannelInfo, SamplingRateInfo *pSamplingRateInfo);
194
195 /**
196 * \brief Apply TNS and PNS tools.
197 */
198 void ApplyTools ( CAacDecoderChannelInfo *pAacDecoderChannelInfo[],
199 const SamplingRateInfo *pSamplingRateInfo,
200 const UINT flags,
201 const int channel );
202
203 /**
204 * \brief Transform MDCT spectral data into time domain
205 */
206 void CBlock_FrequencyToTime(CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo,
207 CAacDecoderChannelInfo *pAacDecoderChannelInfo,
208 INT_PCM outSamples[],
209 const SHORT frameLen,
210 const int stride,
211 const int frameOk,
212 FIXP_DBL *pWorkBuffer1);
213
214 /**
215 * \brief Transform double lapped MDCT (AAC-ELD) spectral data into time domain.
216 */
217 void CBlock_FrequencyToTimeLowDelay(CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo,
218 CAacDecoderChannelInfo *pAacDecoderChannelInfo,
219 INT_PCM outSamples[],
220 const short frameLen,
221 const char stride);
222
223 AAC_DECODER_ERROR CBlock_InverseQuantizeSpectralData(CAacDecoderChannelInfo *pAacDecoderChannelInfo, SamplingRateInfo *pSamplingRateInfo);
224
225 /**
226 * \brief Calculate 2^(lsb/4) * value^(4/3)
227 * \param pValue pointer to quantized value. The inverse quantized result is stored back here.
228 * \param lsb 2 LSBs of the scale factor (scaleFactor % 4) applied as power 2 factor to the
229 * resulting inverse quantized value.
230 * \return the exponent of the result (mantissa) stored into *pValue.
231 */
232 FDK_INLINE
EvaluatePower43(FIXP_DBL * pValue,UINT lsb)233 int EvaluatePower43 ( FIXP_DBL *pValue,
234 UINT lsb )
235 {
236 FIXP_DBL value;
237 UINT freeBits;
238 UINT exponent;
239
240 value = *pValue;
241 freeBits = fNormz (value) ;
242 exponent = DFRACT_BITS - freeBits ;
243 FDK_ASSERT (exponent < 14);
244
245 UINT x = (((int)value << freeBits) >> 19) ;
246 UINT tableIndex = (x & 0x0FFF) >> 4 ;
247 FIXP_DBL invQVal ;
248
249 x = x & 0x0F;
250
251 UINT r0=(LONG)InverseQuantTable [tableIndex+0];
252 UINT r1=(LONG)InverseQuantTable [tableIndex+1];
253 USHORT nx=16-x;
254 UINT temp=(r0)*nx+(r1)*x;
255 invQVal = (FIXP_DBL)temp;
256
257 FDK_ASSERT(lsb < 4);
258 *pValue = fMultDiv2 (invQVal, MantissaTable [lsb][exponent]) ;
259
260 /* + 1 compensates fMultDiv2(). */
261 return ExponentTable [lsb][exponent] + 1;
262 }
263
264 /**
265 * \brief determine the required shift scale for the given quantized value and scale (factor % 4) value.
266 */
GetScaleFromValue(FIXP_DBL value,unsigned int lsb)267 FDK_INLINE int GetScaleFromValue (FIXP_DBL value, unsigned int lsb)
268 {
269 if (value!=(FIXP_DBL)0)
270 {
271 int scale = EvaluatePower43 (&value, lsb) ;
272 return CntLeadingZeros (value) - scale - 2 ;
273 }
274 else
275 return 0; /* Return zero, because its useless to scale a zero value, saves workload and avoids scaling overshifts. */
276 }
277
278
279 //#ifdef AACDEC_HUFFMANDECODER_ENABLE
280
281 /*!
282 \brief Read huffman codeword
283
284 The function reads the huffman codeword from the bitstream and
285 returns the index value.
286
287 \return index value
288 */
CBlock_DecodeHuffmanWord(HANDLE_FDK_BITSTREAM bs,const CodeBookDescription * hcb)289 inline int CBlock_DecodeHuffmanWord( HANDLE_FDK_BITSTREAM bs, /*!< pointer to bitstream */
290 const CodeBookDescription *hcb ) /*!< pointer to codebook description */
291 {
292 UINT val;
293 UINT index = 0;
294 const USHORT (*CodeBook) [HuffmanEntries] = hcb->CodeBook;
295
296 while (1)
297 {
298 val = CodeBook[index][FDKreadBits(bs,HuffmanBits)]; /* Expensive memory access */
299
300 if ((val & 1) == 0)
301 {
302 index = val>>2;
303 continue;
304 }
305 else
306 {
307 if (val & 2)
308 {
309 FDKpushBackCache(bs,1);
310 }
311
312 val >>= 2;
313 break;
314 }
315 }
316
317 return val;
318 }
319
320 //#endif /* AACDEC_HUFFMANDECODER_ENABLE */
321
322 #endif /* #ifndef BLOCK_H */
323