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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 encoder library ******************************
96 
97    Author(s):
98 
99    Description:
100 
101 *******************************************************************************/
102 
103 /*!
104   \file
105   \brief  Noise floor estimation structs and prototypes $Revision: 92790 $
106 */
107 
108 #ifndef NF_EST_H
109 #define NF_EST_H
110 
111 #include "sbr_encoder.h"
112 #include "fram_gen.h"
113 
114 #define NF_SMOOTHING_LENGTH 4 /*!< Smoothing length of the noise floors. */
115 
116 typedef struct {
117   FIXP_DBL
118   prevNoiseLevels[NF_SMOOTHING_LENGTH]
119                  [MAX_NUM_NOISE_VALUES]; /*!< The previous noise levels. */
120   FIXP_DBL noiseFloorOffset
121       [MAX_NUM_NOISE_VALUES];   /*!< Noise floor offset, scaled with
122                                    NOISE_FLOOR_OFFSET_SCALING */
123   const FIXP_DBL *smoothFilter; /*!< Smoothing filter to use. */
124   FIXP_DBL ana_max_level;       /*!< Max level allowed.   */
125   FIXP_DBL weightFac; /*!< Weightening factor for the difference between orig
126                          and sbr. */
127   INT freqBandTableQmf[MAX_NUM_NOISE_VALUES +
128                        1]; /*!< Frequncy band table for the noise floor bands.*/
129   INT noNoiseBands;        /*!< Number of noisebands. */
130   INT noiseBands;          /*!< NoiseBands switch 4 bit.*/
131   INT timeSlots;           /*!< Number of timeslots in a frame. */
132   INVF_MODE diffThres;     /*!< Threshold value to control the inverse filtering
133                               decision */
134 } SBR_NOISE_FLOOR_ESTIMATE;
135 
136 typedef SBR_NOISE_FLOOR_ESTIMATE *HANDLE_SBR_NOISE_FLOOR_ESTIMATE;
137 
138 void FDKsbrEnc_sbrNoiseFloorEstimateQmf(
139     HANDLE_SBR_NOISE_FLOOR_ESTIMATE
140         h_sbrNoiseFloorEstimate, /*!< Handle to SBR_NOISE_FLOOR_ESTIMATE struct
141                                   */
142     const SBR_FRAME_INFO
143         *frame_info, /*!< Time frequency grid of the current frame. */
144     FIXP_DBL
145         *noiseLevels, /*!< Pointer to vector to store the noise levels in.*/
146     FIXP_DBL **quotaMatrixOrig, /*!< Matrix holding the quota values of the
147                                    original. */
148     SCHAR *indexVector,         /*!< Index vector to obtain the patched data. */
149     INT missingHarmonicsFlag,   /*!< Flag indicating if a strong tonal component
150                                    will be missing. */
151     INT startIndex,             /*!< Start index. */
152     UINT numberOfEstimatesPerFrame, /*!< The number of tonality estimates per
153                                        frame. */
154     INT transientFrame, /*!< A flag indicating if a transient is present. */
155     INVF_MODE *pInvFiltLevels, /*!< Pointer to the vector holding the inverse
156                                   filtering levels. */
157     UINT sbrSyntaxFlags);
158 
159 INT FDKsbrEnc_InitSbrNoiseFloorEstimate(
160     HANDLE_SBR_NOISE_FLOOR_ESTIMATE
161         h_sbrNoiseFloorEstimate, /*!< Handle to SBR_NOISE_FLOOR_ESTIMATE struct
162                                   */
163     INT ana_max_level,           /*!< Maximum level of the adaptive noise. */
164     const UCHAR *freqBandTable,  /*!< Frequany band table. */
165     INT nSfb,                    /*!< Number of frequency bands. */
166     INT noiseBands,              /*!< Number of noise bands per octave. */
167     INT noiseFloorOffset,        /*!< Noise floor offset. */
168     INT timeSlots,               /*!< Number of time slots in a frame. */
169     UINT useSpeechConfig /*!< Flag: adapt tuning parameters according to speech
170                           */
171 );
172 
173 INT FDKsbrEnc_resetSbrNoiseFloorEstimate(
174     HANDLE_SBR_NOISE_FLOOR_ESTIMATE
175         h_sbrNoiseFloorEstimate, /*!< Handle to SBR_NOISE_FLOOR_ESTIMATE struct
176                                   */
177     const UCHAR *freqBandTable,  /*!< Frequany band table. */
178     INT nSfb); /*!< Number of bands in the frequency band table. */
179 
180 void FDKsbrEnc_deleteSbrNoiseFloorEstimate(
181     HANDLE_SBR_NOISE_FLOOR_ESTIMATE
182         h_sbrNoiseFloorEstimate); /*!< Handle to SBR_NOISE_FLOOR_ESTIMATE struct
183                                    */
184 
185 #endif
186