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1 /* -----------------------------------------------------------------------------
2 Software License for The Fraunhofer FDK AAC Codec Library for Android
3 
4 © Copyright  1995 - 2023 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):   Christian Griebel
98 
99    Description: Dynamic range control (DRC) decoder tool for AAC
100 
101 *******************************************************************************/
102 
103 #ifndef AACDEC_DRC_H
104 #define AACDEC_DRC_H
105 
106 #include "tp_data.h" /* for program config element support */
107 
108 #include "aacdec_drc_types.h"
109 #include "channel.h"
110 #include "FDK_bitstream.h"
111 
112 #define AACDEC_DRC_GAIN_SCALING (11) /* Scaling of DRC gains */
113 #define AACDEC_DRC_GAIN_INIT_VALUE \
114   (FL2FXCONST_DBL(                 \
115       1.0f / (1 << AACDEC_DRC_GAIN_SCALING))) /* Init value for DRC gains */
116 
117 #define AACDEC_DRC_DFLT_EXPIRY_FRAMES \
118   (0) /* Default DRC data expiry time in AAC frames   */
119 
120 /* #define AACDEC_DRC_IGNORE_FRAMES_WITH_MULTIPLE_CH_THREADS */ /* The name says
121                                                                    it all. */
122 /* #define AACDEC_DRC_DEBUG */
123 
124 /**
125  * \brief DRC module setting parameters
126  */
127 typedef enum {
128   DRC_CUT_SCALE = 0,
129   DRC_BOOST_SCALE,
130   TARGET_REF_LEVEL,
131   DRC_BS_DELAY,
132   DRC_DATA_EXPIRY_FRAME,
133   APPLY_HEAVY_COMPRESSION,
134   DEFAULT_PRESENTATION_MODE,
135   ENCODER_TARGET_LEVEL,
136   MAX_OUTPUT_CHANNELS
137 } AACDEC_DRC_PARAM;
138 
139 /**
140  * \brief DRC module interface functions
141  */
142 void aacDecoder_drcDisable(HANDLE_AAC_DRC self);
143 
144 void aacDecoder_drcReset(HANDLE_AAC_DRC self);
145 
146 void aacDecoder_drcInit(HANDLE_AAC_DRC self);
147 
148 void aacDecoder_drcInitChannelData(CDrcChannelData *pDrcChannel);
149 
150 AAC_DECODER_ERROR aacDecoder_drcSetParam(HANDLE_AAC_DRC self,
151                                          AACDEC_DRC_PARAM param, INT value);
152 
153 int aacDecoder_drcMarkPayload(HANDLE_AAC_DRC self, HANDLE_FDK_BITSTREAM hBs,
154                               AACDEC_DRC_PAYLOAD_TYPE type);
155 
156 int aacDecoder_drcProlog(
157     HANDLE_AAC_DRC self, HANDLE_FDK_BITSTREAM hBs,
158     CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo[],
159     UCHAR pceInstanceTag, UCHAR channelMapping[], int validChannels);
160 
161 /**
162  * \brief Apply DRC. If SBR is present, DRC data is handed over to the SBR
163  * decoder.
164  * \param self AAC decoder instance
165  * \param pSbrDec pointer to SBR decoder instance
166  * \param pAacDecoderChannelInfo AAC decoder channel instance to be processed
167  * \param pDrcDat DRC channel data
168  * \param extGain Pointer to a FIXP_DBL where a externally applyable gain will
169  * be stored into (independently on whether it will be apply internally or not).
170  *                At function call the buffer must hold the scale (0 >= scale <
171  * DFRACT_BITS) to be applied on the gain value.
172  * \param ch channel index
173  * \param aacFrameSize AAC frame size
174  * \param bSbrPresent flag indicating that SBR is present, in which case DRC is
175  * handed over to the SBR instance pSbrDec
176  */
177 void aacDecoder_drcApply(HANDLE_AAC_DRC self, void *pSbrDec,
178                          CAacDecoderChannelInfo *pAacDecoderChannelInfo,
179                          CDrcChannelData *pDrcDat, FIXP_DBL *extGain, int ch,
180                          int aacFrameSize, int bSbrPresent);
181 
182 int aacDecoder_drcEpilog(
183     HANDLE_AAC_DRC self, HANDLE_FDK_BITSTREAM hBs,
184     CAacDecoderStaticChannelInfo *pAacDecoderStaticChannelInfo[],
185     UCHAR pceInstanceTag, UCHAR channelMapping[], int validChannels);
186 
187 /**
188  * \brief Get metadata information found in bitstream.
189  * \param self DRC module instance handle.
190  * \param pPresMode Pointer to field where the presentation mode will be written
191  * to.
192  * \param pProgRefLevel Pointer to field where the program reference level will
193  * be written to.
194  * \return Nothing.
195  */
196 void aacDecoder_drcGetInfo(HANDLE_AAC_DRC self, SCHAR *pPresMode,
197                            SCHAR *pProgRefLevel);
198 
199 /**
200  * \brief  Apply DRC Level Normalization.
201  *
202  *         This function prepares/applies the gain values for the DRC Level
203  * Normalization and returns the exponent of the time data. The following two
204  * cases are handled:
205  *
206  *         - Limiter enabled:
207  *           The input data must be interleaved.
208  *           One gain per sample is written to the buffer pGainPerSample.
209  *           If necessary the time data is rescaled.
210  *
211  *         - Limiter disabled:
212  *           The input data can be interleaved or deinterleaved.
213  *           The gain values are applied to the time data.
214  *           If necessary the time data is rescaled.
215  *
216  * \param hDrcInfo                     [i/o] handle to drc data structure.
217  * \param samplesIn                    [i/o] pointer to time data.
218  * \param pGain                        [i  ] pointer to gain to be applied to
219  * the time data.
220  * \param pGainPerSample               [o  ] pointer to the gain per sample to
221  * be applied to the time data in the limiter.
222  * \param gain_scale                   [i  ] exponent to be applied to the time
223  * data.
224  * \param gain_delay                   [i  ] delay[samples] with which the gains
225  * in pGain shall be applied (gain_delay <= nSamples).
226  * \param nSamples                     [i  ] number of samples per frame.
227  * \param channels                     [i  ] number of channels.
228  * \param stride                       [i  ] channel stride of time data.
229  * \param limiterEnabled               [i  ] 1 if limiter is enabled, otherwise
230  * 0.
231  *
232  * \return exponent of time data
233  */
234 INT applyDrcLevelNormalization(HANDLE_AAC_DRC hDrcInfo, PCM_DEC *samplesIn,
235                                FIXP_DBL *pGain, FIXP_DBL *pGainPerSample,
236                                const INT gain_scale, const UINT gain_delay,
237                                const UINT nSamples, const UINT channels,
238                                const UINT stride, const UINT limiterEnabled);
239 
240 #endif /* AACDEC_DRC_H */
241