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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 /**************************** SBR decoder library ******************************
96 
97    Author(s):
98 
99    Description:
100 
101 *******************************************************************************/
102 
103 /*!
104   \file
105   \brief  Envelope calculation prototypes
106 */
107 #ifndef ENV_CALC_H
108 #define ENV_CALC_H
109 
110 #include "sbrdecoder.h"
111 #include "env_extr.h" /* for HANDLE_SBR_HEADER_DATA */
112 
113 typedef struct {
114   FIXP_DBL filtBuffer[MAX_FREQ_COEFFS];      /*!< previous gains (required for
115                                                 smoothing) */
116   FIXP_DBL filtBufferNoise[MAX_FREQ_COEFFS]; /*!< previous noise levels
117                                                 (required for smoothing) */
118   SCHAR filtBuffer_e[MAX_FREQ_COEFFS];       /*!< Exponents of previous gains */
119   SCHAR filtBufferNoise_e; /*!< Common exponent of previous noise levels */
120 
121   int startUp;     /*!< flag to signal initial conditions in buffers */
122   int phaseIndex;  /*!< Index for randomPase array */
123   int prevTranEnv; /*!< The transient envelope of the previous frame. */
124 
125   ULONG harmFlagsPrev[ADD_HARMONICS_FLAGS_SIZE];
126   /*!< Words with 16 flags each indicating where a sine was added in the
127    * previous frame.*/
128   UCHAR harmIndex;     /*!< Current phase of synthetic sine */
129   int sbrPatchingMode; /*!< Current patching mode           */
130 
131   FIXP_SGL prevSbrNoiseFloorLevel[MAX_NOISE_COEFFS];
132   UCHAR prevNNfb;
133   UCHAR prevNSfb[2];
134   UCHAR prevLoSubband;
135   UCHAR prevHiSubband;
136   UCHAR prev_ov_highSubband;
137   UCHAR *prevFreqBandTable[2];
138   UCHAR prevFreqBandTableLo[MAX_FREQ_COEFFS / 2 + 1];
139   UCHAR prevFreqBandTableHi[MAX_FREQ_COEFFS + 1];
140   UCHAR prevFreqBandTableNoise[MAX_NOISE_COEFFS + 1];
141   SCHAR sinusoidal_positionPrev;
142   ULONG harmFlagsPrevActive[ADD_HARMONICS_FLAGS_SIZE];
143 } SBR_CALCULATE_ENVELOPE;
144 
145 typedef SBR_CALCULATE_ENVELOPE *HANDLE_SBR_CALCULATE_ENVELOPE;
146 
147 void calculateSbrEnvelope(
148     QMF_SCALE_FACTOR *sbrScaleFactor,
149     HANDLE_SBR_CALCULATE_ENVELOPE h_sbr_cal_env,
150     HANDLE_SBR_HEADER_DATA hHeaderData, HANDLE_SBR_FRAME_DATA hFrameData,
151     PVC_DYNAMIC_DATA *pPvcDynamicData, FIXP_DBL **analysBufferReal,
152     FIXP_DBL *
153         *analysBufferImag, /*!< Imag part of subband samples to be processed */
154     const int useLP,
155     FIXP_DBL *degreeAlias, /*!< Estimated aliasing for each QMF channel */
156     const UINT flags, const int frameErrorFlag);
157 
158 SBR_ERROR
159 createSbrEnvelopeCalc(HANDLE_SBR_CALCULATE_ENVELOPE hSbrCalculateEnvelope,
160                       HANDLE_SBR_HEADER_DATA hHeaderData, const int chan,
161                       const UINT flags);
162 
163 int deleteSbrEnvelopeCalc(HANDLE_SBR_CALCULATE_ENVELOPE hSbrCalculateEnvelope);
164 
165 void resetSbrEnvelopeCalc(HANDLE_SBR_CALCULATE_ENVELOPE hCalEnv);
166 
167 SBR_ERROR
168 ResetLimiterBands(UCHAR *limiterBandTable, UCHAR *noLimiterBands,
169                   UCHAR *freqBandTable, int noFreqBands,
170                   const PATCH_PARAM *patchParam, int noPatches,
171                   int limiterBands, UCHAR sbrPatchingMode,
172                   int xOverQmf[MAX_NUM_PATCHES], int sbrRatio);
173 
174 void rescaleSubbandSamples(FIXP_DBL **re, FIXP_DBL **im, int lowSubband,
175                            int noSubbands, int start_pos, int next_pos,
176                            int shift);
177 
178 FIXP_DBL maxSubbandSample(FIXP_DBL **analysBufferReal_m,
179                           FIXP_DBL **analysBufferImag_m, int lowSubband,
180                           int highSubband, int start_pos, int stop_pos);
181 
182 #endif  // ENV_CALC_H
183