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): Matthias Hildenbrand
98
99 Description: USAC ACELP frame decoder
100
101 *******************************************************************************/
102
103 #ifndef USACDEC_ACELP_H
104 #define USACDEC_ACELP_H
105
106 #include "common_fix.h"
107 #include "FDK_bitstream.h"
108 #include "usacdec_const.h"
109 #include "usacdec_rom.h"
110
111 //#define ENHANCED_TCX_TD_CONCEAL_ENABLE
112
113 /** Structure which holds the ACELP internal persistent memory */
114 typedef struct {
115 FIXP_DBL old_exc_mem[PIT_MAX_MAX + L_INTERPOL];
116 FIXP_DBL old_syn_mem[M_LP_FILTER_ORDER]; /* synthesis filter states */
117 FIXP_SGL A[M_LP_FILTER_ORDER];
118 INT A_exp;
119 FIXP_DBL gc_threshold;
120 FIXP_DBL de_emph_mem;
121 FIXP_SGL past_gpit;
122 FIXP_DBL past_gcode;
123 USHORT old_T0;
124 UCHAR old_T0_frac;
125 FIXP_DBL deemph_mem_wsyn;
126 FIXP_DBL wsyn_rms;
127 SHORT seed_ace;
128 } CAcelpStaticMem;
129
130 /** Structure which holds the parameter data needed to decode one ACELP frame.
131 */
132 typedef struct {
133 UCHAR
134 acelp_core_mode; /**< mean excitation energy index for whole ACELP frame
135 */
136 UCHAR mean_energy; /**< acelp core mode for whole ACELP frame */
137 USHORT T0[NB_SUBFR];
138 UCHAR T0_frac[NB_SUBFR];
139 UCHAR ltp_filtering_flag[NB_SUBFR]; /**< controlls whether LTP postfilter is
140 active for each ACELP subframe */
141 SHORT icb_index[NB_SUBFR]
142 [8]; /**< innovative codebook index for each ACELP subframe */
143 UCHAR gains[NB_SUBFR]; /**< gain index for each ACELP subframe */
144 } CAcelpChannelData;
145
146 /**
147 * \brief Read the acelp_coding() bitstream part.
148 * \param[in] hBs bitstream handle to read data from.
149 * \param[out] acelpData pointer to structure to store the parsed data of one
150 * ACELP frame.
151 * \param[in] acelp_core_mode the ACELP core mode index.
152 * \param[in] coreCoderFrameLength length of core coder frame (1024|768)
153 */
154 INT CLpd_AcelpRead(HANDLE_FDK_BITSTREAM hBs, CAcelpChannelData *acelpData,
155 INT acelp_core_mode, INT i_offset, INT coreCoderFrameLength);
156 /**
157 * \brief Initialization of memory before one LPD frame is decoded
158 * \param[out] synth_buf synthesis buffer to be initialized, exponent = SF_SYNTH
159 * \param[in] old_synth past synthesis of previous LPD frame, exponent =
160 * SF_SYNTH
161 * \param[out] synth_buf_fb fullband synthesis buffer to be initialized,
162 * exponent = SF_SYNTH
163 * \param[in] old_synth_fb past fullband synthesis of previous LPD frame,
164 * exponent = SF_SYNTH
165 * \param[out] pitch vector where decoded pitch lag values are stored
166 * \param[in] old_T_pf past pitch lag values of previous LPD frame
167 * \param[in] samplingRate sampling rate for pitch lag offset calculation
168 * \param[out] i_offset pitch lag offset for the decoding of the pitch lag
169 * \param[in] coreCoderFrameLength length of core coder frame (1024|768)
170 */
171 void Acelp_PreProcessing(FIXP_DBL *synth_buf, FIXP_DBL *old_synth, INT *pitch,
172 INT *old_T_pf, FIXP_DBL *pit_gain,
173 FIXP_DBL *old_gain_pf, INT samplingRate, INT *i_offset,
174 INT coreCoderFrameLength, INT synSfd,
175 INT nbSubfrSuperfr);
176
177 /**
178 * \brief Save tail of buffers for the initialization of the next LPD frame
179 * \param[in] synth_buf synthesis of current LPD frame, exponent = SF_SYNTH
180 * \param[out] old_synth memory where tail of fullband synth_buf is stored,
181 * exponent = SF_SYNTH
182 * \param[in] synth_buf_fb fullband synthesis of current LPD frame, exponent =
183 * SF_SYNTH
184 * \param[out] old_synth_fb memory where tail of fullband synth_buf is stored,
185 * exponent = SF_SYNTH
186 * \param[in] pitch decoded pitch lag values of current LPD frame
187 * \param[out] old_T_pf memory where last SYN_SFD pitch lag values are stored
188 */
189 void Acelp_PostProcessing(FIXP_DBL *synth_buf, FIXP_DBL *old_synth, INT *pitch,
190 INT *old_T_pf, INT coreCoderFrameLength, INT synSfd,
191 INT nbSubfrSuperfr);
192
193 /**
194 * \brief Decode one ACELP frame (three or four ACELP subframes with 64 samples
195 * each)
196 * \param[in,out] acelp_mem pointer to ACELP memory structure
197 * \param[in] i_offset pitch lag offset
198 * \param[in] lsp_old LPC filter in LSP domain corresponding to previous frame
199 * \param[in] lsp_new LPC filter in LSP domain corresponding to current frame
200 * \param[in] stab_fac stability factor constrained by 0<=stab_fac<=1.0,
201 * exponent = SF_STAB
202 * \param[in] acelpData pointer to struct with data which is needed for decoding
203 * one ACELP frame
204 * \param[out] synth ACELP output signal
205 * \param[out] pT four decoded pitch lag values
206 * \param[in] coreCoderFrameLength length of core coder frame (1024|768)
207 */
208 void CLpd_AcelpDecode(CAcelpStaticMem *acelp_mem, INT i_offset,
209 const FIXP_LPC lsp_old[M_LP_FILTER_ORDER],
210 const FIXP_LPC lsp_new[M_LP_FILTER_ORDER],
211 FIXP_SGL stab_fac, CAcelpChannelData *acelpData,
212 INT numLostSubframes, int lastLpcLost, int frameCnt,
213 FIXP_DBL synth[], int pT[], FIXP_DBL *pit_gain,
214 INT coreCoderFrameLength);
215
216 /**
217 * \brief Reset ACELP internal memory.
218 * \param[out] acelp_mem pointer to ACELP memory structure
219 */
220 void CLpd_AcelpReset(CAcelpStaticMem *acelp_mem);
221
222 /**
223 * \brief Initialize ACELP internal memory in case of FAC before ACELP decoder
224 * is called
225 * \param[in] synth points to end+1 of past valid synthesis signal, exponent =
226 * SF_SYNTH
227 * \param[in] last_lpd_mode last lpd mode
228 * \param[in] last_last_lpd_mode lpd mode before last_lpd_mode
229 * \param[in] A_new LP synthesis filter coeffs corresponding to last frame,
230 * exponent = SF_A_COEFFS
231 * \param[in] A_old LP synthesis filter coeffs corresponding to the frame before
232 * last frame, exponent = SF_A_COEFFS
233 * \param[in,out] acelp_mem pointer to ACELP memory structure
234 * \param[in] coreCoderFrameLength length of core coder frame (1024|768)
235 */
236 void CLpd_AcelpPrepareInternalMem(const FIXP_DBL *synth, UCHAR last_lpd_mode,
237 UCHAR last_last_lpd_mode,
238 const FIXP_LPC *A_new, const INT A_new_exp,
239 const FIXP_LPC *A_old, const INT A_old_exp,
240 CAcelpStaticMem *acelp_mem,
241 INT coreCoderFrameLength, INT clearOldExc,
242 UCHAR lpd_mode);
243
244 /**
245 * \brief Calculate zero input response (zir) of the acelp synthesis filter
246 * \param[in] A LP synthesis filter coefficients, exponent = SF_A_COEFFS
247 * \param[in,out] acelp_mem pointer to ACELP memory structure
248 * \param[in] length length of zir
249 * \param[out] zir pointer to zir output buffer, exponent = SF_SYNTH
250 */
251 void CLpd_Acelp_Zir(const FIXP_LPC A[], const INT A_exp,
252 CAcelpStaticMem *acelp_mem, const INT length,
253 FIXP_DBL zir[], int doDeemph);
254
255 /**
256 * \brief Borrow static excitation memory from ACELP decoder
257 * \param[in] acelp_mem pointer to ACELP memory structure
258 * \param[in] length number of requested FIXP_DBL values
259 * \return pointer to requested memory
260 *
261 * The caller has to take care not to overwrite valid memory areas.
262 * During TCX/FAC calculations and before CLpd_AcelpPrepareInternalMem() is
263 * called, the following memory size is available:
264 * - 256 samples in case of ACELP -> TCX20 -> ACELP transition
265 * - PIT_MAX_MAX+L_INTERPOL samples in all other cases
266 */
267 FIXP_DBL *CLpd_ACELP_GetFreeExcMem(CAcelpStaticMem *acelp_mem, INT length);
268
269 void CLpd_TcxTDConceal(CAcelpStaticMem *acelp_mem, SHORT *pitch,
270 const FIXP_LPC lsp_old[M_LP_FILTER_ORDER],
271 const FIXP_LPC lsp_new[M_LP_FILTER_ORDER],
272 const FIXP_SGL stab_fac, INT numLostSubframes,
273 FIXP_DBL synth[], INT coreCoderFrameLength,
274 UCHAR last_tcx_noise_factor);
275
E_UTIL_random(SHORT * seed)276 inline SHORT E_UTIL_random(SHORT *seed) {
277 *seed = (SHORT)((((LONG)*seed * (LONG)31821) >> 1) + (LONG)13849);
278 return (*seed);
279 }
280
281 #endif /* USACDEC_ACELP_H */
282