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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, Manuel Jander
98 
99    Description: USAC LPC/AVQ decode
100 
101 *******************************************************************************/
102 
103 #ifndef USACDEC_LPC_H
104 #define USACDEC_LPC_H
105 
106 #include "channelinfo.h"
107 #include "common_fix.h"
108 #include "FDK_bitstream.h"
109 #include "usacdec_rom.h"
110 
111 #define LSPARG_SCALE 10
112 
113 /**
114  * \brief AVQ (refinement) decode
115  * \param hBs bitstream handle
116  * \param lsfq buffer for AVQ decode output.
117  * \param nk_mode quantization mode.
118  * \param nqn amount of split/interleaved RE8 vectors.
119  * \param total amount of individual data values to decode.
120  * \return 0 on success, -1 on error.
121  */
122 int CLpc_DecodeAVQ(HANDLE_FDK_BITSTREAM hBs, FIXP_DBL *lsfq, int nk_mode,
123                    int nqn, int length);
124 
125 /**
126  * \brief Read and decode LPC coeficient sets. First stage approximation + AVQ
127  * decode.
128  * \param[in]  hBs bitstream handle to read data from.
129  * \param[out] lsp buffer into which the decoded LSP coefficients will be stored
130  * into.
131  * \param[in,out] lpc4_lsf buffer into which the decoded LCP4 LSF coefficients
132  * will be stored into (persistent).
133  * \param[out] lsf_adaptive_mean_cand lsf adaptive mean vector needed for
134  * concealment.
135  * \param[out] pStability array with stability values for the ACELP decoder (and
136  * concealment).
137  * \param[in]  mod array which defines modes (ACELP, TCX20|40|80) are used in
138  * the current superframe.
139  * \param[in]  first_lpd_flag indicates the presence of LPC0
140  * \param[in]  last_lpc_lost indicate that LPC4 of previous frame was lost.
141  * \param[in]  last_frame_ok indicate that the last frame was ok.
142  * \return 0 on success, -1 on error.
143  */
144 int CLpc_Read(HANDLE_FDK_BITSTREAM hBs, FIXP_LPC lsp[][M_LP_FILTER_ORDER],
145               FIXP_LPC lpc4_lsf[M_LP_FILTER_ORDER],
146               FIXP_LPC lsf_adaptive_mean_cand[M_LP_FILTER_ORDER],
147               FIXP_SGL pStability[], UCHAR *mod, int first_lpd_flag,
148               int last_lpc_lost, int last_frame_ok);
149 
150 /**
151  * \brief Generate LPC coefficient sets in case frame loss.
152  * \param lsp buffer into which the decoded LSP coefficients will be stored
153  * into.
154  * \param lpc4_lsf buffer into which the decoded LCP4 LSF coefficients will be
155  * stored into (persistent).
156  * \param isf_adaptive_mean
157  * \param first_lpd_flag indicates the previous LSF4 coefficients lpc4_lsf[] are
158  * not valid.
159  */
160 void CLpc_Conceal(FIXP_LPC lsp[][M_LP_FILTER_ORDER],
161                   FIXP_LPC lpc4_lsf[M_LP_FILTER_ORDER],
162                   FIXP_LPC isf_adaptive_mean[M_LP_FILTER_ORDER],
163                   const int first_lpd_flag);
164 
165 /**
166  * \brief apply absolute weighting
167  * \param A weighted LPC coefficient vector output. The first coeffcient is
168  * implicitly 1.0
169  * \param A LPC coefficient vector. The first coeffcient is implicitly 1.0
170  * \param m length of vector A
171  */
172 /* static */
173 void E_LPC_a_weight(FIXP_LPC *wA, const FIXP_LPC *A, const int m);
174 
175 /**
176  * \brief decode TCX/FAC gain. In case of TCX the lg/sqrt(rms) part
177  *        must still be applied to obtain the gain value.
178  * \param gain (o) pointer were the gain mantissa is stored into.
179  * \param gain_e (o) pointer were the gain exponent is stored into.
180  * \param gain_code (i) the 7 bit binary word from the bitstream
181  *                      representing the gain.
182  */
183 void CLpd_DecodeGain(FIXP_DBL *gain, INT *gain_e, int gain_code);
184 
185 /**
186  * \brief convert LSP coefficients into LP domain.
187  */
188 void E_LPC_f_lsp_a_conversion(FIXP_LPC *lsp, FIXP_LPC *a, INT *a_exp);
189 
190 #endif /* USACDEC_LPC_H */
191