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1 
2 /* -----------------------------------------------------------------------------------------------------------
3 Software 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
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 /*!
85   \file   qmf.h
86   \brief  Complex qmf analysis/synthesis
87   \author Markus Werner
88 
89 */
90 #ifndef __QMF_H
91 #define __QMF_H
92 
93 
94 
95 #include "common_fix.h"
96 #include "FDK_tools_rom.h"
97 #include "dct.h"
98 
99 /*
100  * Filter coefficient type definition
101  */
102 #ifdef QMF_DATA_16BIT
103 #define FIXP_QMF FIXP_SGL
104 #define FX_DBL2FX_QMF FX_DBL2FX_SGL
105 #define FX_QMF2FX_DBL FX_SGL2FX_DBL
106 #define QFRACT_BITS FRACT_BITS
107 #else
108 #define FIXP_QMF FIXP_DBL
109 #define FX_DBL2FX_QMF
110 #define FX_QMF2FX_DBL
111 #define QFRACT_BITS DFRACT_BITS
112 #endif
113 
114 /* ARM neon optimized QMF analysis filter requires 32 bit input.
115    Implemented for RVCT only, currently disabled. See src/arm/qmf_arm.cpp:45 */
116 #define FIXP_QAS FIXP_PCM
117 #define QAS_BITS SAMPLE_BITS
118 
119 #ifdef QMFSYN_STATES_16BIT
120 #define FIXP_QSS FIXP_SGL
121 #define QSS_BITS FRACT_BITS
122 #else
123 #define FIXP_QSS FIXP_DBL
124 #define QSS_BITS DFRACT_BITS
125 #endif
126 
127 /* Flags for QMF intialization */
128 /* Low Power mode flag */
129 #define QMF_FLAG_LP           1
130 /* Filter is not symetric. This flag is set internally in the QMF initialization as required. */
131 #define QMF_FLAG_NONSYMMETRIC 2
132 /* Complex Low Delay Filter Bank (or std symmetric filter bank) */
133 #define QMF_FLAG_CLDFB        4
134 /* Flag indicating that the states should be kept. */
135 #define QMF_FLAG_KEEP_STATES  8
136 /* Complex Low Delay Filter Bank used in MPEG Surround Encoder */
137 #define QMF_FLAG_MPSLDFB     16
138 /* Complex Low Delay Filter Bank used in MPEG Surround Encoder allows a optimized calculation of the modulation in qmfForwardModulationHQ() */
139 #define QMF_FLAG_MPSLDFB_OPTIMIZE_MODULATION  32
140 /* Flag to indicate HE-AAC down-sampled SBR mode (decoder) -> adapt analysis post twiddling */
141 #define QMF_FLAG_DOWNSAMPLED  64
142 
143 
144 typedef struct
145 {
146   int lb_scale;        /*!< Scale of low band area                   */
147   int ov_lb_scale;     /*!< Scale of adjusted overlap low band area  */
148   int hb_scale;        /*!< Scale of high band area                  */
149   int ov_hb_scale;     /*!< Scale of adjusted overlap high band area */
150 } QMF_SCALE_FACTOR;
151 
152 struct QMF_FILTER_BANK
153 {
154   const FIXP_PFT *p_filter;     /*!< Pointer to filter coefficients */
155 
156   void *FilterStates;           /*!< Pointer to buffer of filter states
157                                      FIXP_PCM in analyse and
158                                      FIXP_DBL in synthesis filter */
159   int FilterSize;               /*!< Size of prototype filter. */
160   const FIXP_QTW *t_cos;        /*!< Modulation tables. */
161   const FIXP_QTW *t_sin;
162   int filterScale;              /*!< filter scale */
163 
164   int no_channels;              /*!< Total number of channels (subbands) */
165   int no_col;                   /*!< Number of time slots       */
166   int lsb;                      /*!< Top of low subbands */
167   int usb;                      /*!< Top of high subbands */
168 
169   int outScalefactor;           /*!< Scale factor of output data (syn only) */
170   FIXP_DBL outGain;             /*!< Gain output data (syn only) (init with 0x80000000 to ignore) */
171 
172   UINT flags;                   /*!< flags */
173   UCHAR p_stride;               /*!< Stride Factor of polyphase filters */
174 
175 };
176 
177 typedef struct QMF_FILTER_BANK *HANDLE_QMF_FILTER_BANK;
178 
179 void
180 qmfAnalysisFiltering( HANDLE_QMF_FILTER_BANK anaQmf,  /*!< Handle of Qmf Analysis Bank   */
181                       FIXP_QMF **qmfReal,             /*!< Pointer to real subband slots */
182                       FIXP_QMF **qmfImag,             /*!< Pointer to imag subband slots */
183                       QMF_SCALE_FACTOR *scaleFactor,  /*!< Scale factors of QMF data     */
184                       const INT_PCM *timeIn,          /*!< Time signal */
185                       const int  stride,              /*!< Stride factor of audio data   */
186                       FIXP_QMF  *pWorkBuffer          /*!< pointer to temporal working buffer */
187                       );
188 
189 void
190 qmfSynthesisFiltering( HANDLE_QMF_FILTER_BANK synQmf,       /*!< Handle of Qmf Synthesis Bank  */
191                        FIXP_QMF  **QmfBufferReal,           /*!< Pointer to real subband slots */
192                        FIXP_QMF  **QmfBufferImag,           /*!< Pointer to imag subband slots */
193                        const QMF_SCALE_FACTOR *scaleFactor, /*!< Scale factors of QMF data     */
194                        const int   ov_len,                  /*!< Length of band overlap        */
195                        INT_PCM    *timeOut,                 /*!< Time signal */
196                        const int   stride,                  /*!< Stride factor of audio data   */
197                        FIXP_QMF   *pWorkBuffer              /*!< pointer to temporal working buffer */
198                        );
199 
200 int
201 qmfInitAnalysisFilterBank( HANDLE_QMF_FILTER_BANK h_Qmf, /*!< QMF Handle */
202                            FIXP_QAS *pFilterStates,      /*!< Pointer to filter state buffer */
203                            int noCols,                   /*!< Number of time slots  */
204                            int lsb,                      /*!< Number of lower bands */
205                            int usb,                      /*!< Number of upper bands */
206                            int no_channels,              /*!< Number of critically sampled bands */
207                            int flags);                   /*!< Flags */
208 
209 void
210 qmfAnalysisFilteringSlot( HANDLE_QMF_FILTER_BANK anaQmf,  /*!< Handle of Qmf Synthesis Bank  */
211                           FIXP_QMF      *qmfReal,         /*!< Low and High band, real */
212                           FIXP_QMF      *qmfImag,         /*!< Low and High band, imag */
213                           const INT_PCM *timeIn,          /*!< Pointer to input */
214                           const int      stride,          /*!< stride factor of input */
215                           FIXP_QMF      *pWorkBuffer      /*!< pointer to temporal working buffer */
216                          );
217 
218 int
219 qmfInitSynthesisFilterBank( HANDLE_QMF_FILTER_BANK h_Qmf, /*!< QMF Handle */
220                             FIXP_QSS *pFilterStates,      /*!< Pointer to filter state buffer */
221                             int noCols,                   /*!< Number of time slots  */
222                             int lsb,                      /*!< Number of lower bands */
223                             int usb,                      /*!< Number of upper bands */
224                             int no_channels,              /*!< Number of critically sampled bands */
225                             int flags);                   /*!< Flags */
226 
227 void qmfSynthesisFilteringSlot( HANDLE_QMF_FILTER_BANK  synQmf,
228                                 const FIXP_QMF *realSlot,
229                                 const FIXP_QMF *imagSlot,
230                                 const int       scaleFactorLowBand,
231                                 const int       scaleFactorHighBand,
232                                 INT_PCM        *timeOut,
233                                 const int       stride,
234                                 FIXP_QMF       *pWorkBuffer);
235 
236 void
237 qmfChangeOutScalefactor (HANDLE_QMF_FILTER_BANK synQmf,     /*!< Handle of Qmf Synthesis Bank */
238                          int outScalefactor                 /*!< New scaling factor for output data */
239                         );
240 
241 void
242 qmfChangeOutGain (HANDLE_QMF_FILTER_BANK synQmf,     /*!< Handle of Qmf Synthesis Bank */
243                   FIXP_DBL outputGain                /*!< New gain for output data */
244                  );
245 
246 
247 
248 #endif /* __QMF_H */
249